java攻城狮之路(Android篇)--MP3 MP4、拍照、国际化、样式主题、图片移动和缩放

一、MP3播放器

查看Android API文档可以看到MediaPlayer状态转换图：

练习：

package com.shellway.mp3player;

import java.io.File;
import java.io.IOException;

import android.support.v7.app.ActionBarActivity;
import android.telephony.PhoneStateListener;
import android.telephony.TelephonyManager;
import android.content.Context;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnPreparedListener;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends ActionBarActivity {
    //媒体播放器
    private MediaPlayer mp;
    private EditText songName;
    //之前是否暂停过
    private boolean pause;
    private File file;
    private TelephonyManager tm;
    //暂停保存点
    private int position = 0;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        songName = (EditText) findViewById(R.id.song_name);
        
        tm = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
        tm.listen(new MyPhoneStateListener(), PhoneStateListener.LISTEN_CALL_STATE);
    }
    
    private class MyPhoneStateListener extends PhoneStateListener{
        @Override
        public void onCallStateChanged(int state, String incomingNumber) {
            // TODO Auto-generated method stub
            super.onCallStateChanged(state, incomingNumber);
            switch (state) {
            case TelephonyManager.CALL_STATE_IDLE://闲置状态
                if (position > 0 && mp != null) {
                    //跳转到指定的保存点位置
                    mp.seekTo(position);
                    mp.start();
                }
                break;
            case TelephonyManager.CALL_STATE_OFFHOOK://接听状态
                if(mp != null){
                    if(mp.isPlaying()){
                        position = mp.getCurrentPosition();
                        mp.pause();
                    }
                }
                break;
            case TelephonyManager.CALL_STATE_RINGING://响铃状态
                
                 if (mp.isPlaying()) {
                     position = mp.getCurrentPosition();
                     mp.pause();
                    }
                break;
                
            default:
                break;
            }
        }
    }
//这里是利用Activity生命周期的方法监听来电时暂停播放
//  @Override
//  protected void onResume() {
//      // TODO Auto-generated method stub
//      super.onResume();
//      if(position > 0){
//          //跳转到指定的位置
//          mp.seekTo(position);
//          mp.start();
//      }
//  }
//  
//  @Override
//  protected void onPause() {
//      // TODO Auto-generated method stub
//      super.onPause();
//      position = mp.getCurrentPosition();
//      mp.pause();
//  }
    
    public void play(View view){
        String name = songName.getText().toString();
        
        file = new File(Environment.getExternalStorageDirectory(),name+".mp3");
        
            if (!file.exists()) {
                Toast.makeText(this, "文件不存在", Toast.LENGTH_SHORT).show();
                mp=null;
            }else{
                if (mp!=null) {
                    if (mp.isPlaying()) {
                        Toast.makeText(this, "歌曲已经在播放中", Toast.LENGTH_SHORT).show();
                    }else{
                        play();
                    }
                }else{
                    play();
                }
         }
    }
    
    public void play(){
        try {
            mp = new MediaPlayer();
            //置为初始状态
            mp.reset();
            //指定要播放的文件
            mp.setDataSource(file.getAbsolutePath());
            //准备(缓冲)
            mp.prepare();
            //设置缓冲完成监听
            mp.setOnPreparedListener(new MyOnPreparedListener());
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    
    private class MyOnPreparedListener implements OnPreparedListener{

        @Override
        public void onPrepared(MediaPlayer mp) {
            // TODO Auto-generated method stub
            //播放
            mp.start();
        }
    }
    
    public void pause(View view){
        if (mp.isPlaying()) {
            //暂停播放
            mp.pause();
            Button bt = (Button) view;
            bt.setText("继续");
            pause = true;
        }else{
            if (pause) {
                mp.start();
                Button bt = (Button) view;
                bt.setText("停止");
            }
        }
    }
    
    public void stop(View view){
        if (mp!=null) {
            //停止播放
            mp.stop();
        }
    }
    
    public void reset(View view){
        if (mp!=null) {
            mp.start();
        }
    }
    
    @Override
    protected void onDestroy() {
        // TODO Auto-generated method stub
        super.onDestroy();
        if (mp != null) {
            mp.release();
            mp = null;
        }
    }
}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="请输入歌曲名" />
    <EditText 
        android:id="@+id/song_name"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="Complicated"
        />
  <LinearLayout 
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        >
    <Button 
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:onClick="play"
        android:text="播放"
        />
    <Button 
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:onClick="pause"
        android:text="暂停"
        />
    <Button 
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:onClick="stop"
        android:text="停止"
        />
    <Button 
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:onClick="reset"
        android:text="重播"
        />
  </LinearLayout>
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.shellway.mp3player"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="21" />
    <!-- 监听来电状态需要读取电话状态权限 -->
    <uses-permission android:name="android.permission.READ_PHONE_STATE"/>
    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

运行结果截图：

二：MP4播放器

 MP4的播放同MP3的差不多，主要是在显示视频的控件上的区别

package com.shellway.mp4player;

import java.io.File;
import java.io.IOException;

import android.support.v7.app.ActionBarActivity;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnCompletionListener;
import android.media.MediaPlayer.OnPreparedListener;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.EditText;
import android.widget.Toast;

public class MainActivity extends ActionBarActivity {
    private MediaPlayer mp;
    private EditText et_name;
    private File file;
    private boolean pause ;
    private SurfaceView surfaceview;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        et_name = (EditText) findViewById(R.id.et_name);
        surfaceview = (SurfaceView) findViewById(R.id.surfaceview);
        SurfaceHolder holder = surfaceview.getHolder();
        //给SurfaceView设置屏幕分辨率
        holder.setFixedSize(176, 144);
        //给SurfaceView设置保持高亮
        holder.setKeepScreenOn(true);
        //不让surfaceview维持自己的缓冲，让它得到的数据直接输出
        holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
    }
    
    public void play(View view){
        String name = et_name.getText().toString();
        file = new File(Environment.getExternalStorageDirectory(),name+".mp4");
        Log.i("i", file.getAbsolutePath());
        if (!file.exists()) {
            Toast.makeText(this, "播放文件不存在", Toast.LENGTH_SHORT).show();
        }else{
            //开始播放
            play();
        }
    }
    
    public void play(){
        try {
            mp = new MediaPlayer();
            mp.reset();
            mp.setDataSource(file.getAbsolutePath());
            //设置显示画面
            mp.setDisplay(surfaceview.getHolder()); 
            mp.prepare();
            mp.setOnPreparedListener(new MyOnPreparedListener());
            
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    
    private class MyOnPreparedListener implements OnPreparedListener{

        @Override
        public void onPrepared(MediaPlayer mp) {
            // TODO Auto-generated method stub
            mp.start();
        }

        
    }
    
    public void pause(View view){
        if (mp != null) {
            if (mp.isPlaying()) {
                mp.pause();
                pause = true;
            }else{
                mp.start();
                pause = false;
            }
        }
    }
    
    public void stop(View view){
        if (mp != null) {
            mp.stop();
        }
    }
    
    public void reset(View view){
        if (mp != null) {
            mp.reset();
            play();
        }
    }
    
    @Override
    protected void onDestroy() {
        // TODO Auto-generated method stub
        super.onDestroy();
        if (mp != null) {
            mp.release();
            mp = null;
        }
    }
}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="请输入要播放的视频名称:" />
    <EditText 
        android:id="@+id/et_name"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="test"
        />
    
    <LinearLayout 
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        >
        <ImageView 
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginRight="10dp"
            android:onClick="play"
            android:src="@drawable/play"
            />
        <ImageView 
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginRight="10dp"
            android:onClick="pause"
            android:src="@drawable/pause"
            />
        <ImageView 
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginRight="10dp"
            android:onClick="stop"
            android:src="@drawable/stop"
            />
        <ImageView 
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginRight="10dp"
            android:onClick="reset"
            android:src="@drawable/reset"
            />
        
    </LinearLayout>
    
    <SurfaceView
            android:id="@+id/surfaceview"
            android:layout_width="fill_parent"
            android:layout_height="240dp"
        ></SurfaceView>

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.shellway.mp4player"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="21" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

运行结果截图：

 三、手机拍照

照相机的一些属性：
预览帧数：preview-frame-rate=30
图片质量：jpeg-thumbnail-quality=90
图片尺寸：preview-size-values=1280x720,800x480,768x432,720x480,640x480,480x320,176x144
SurfaceView只有当activity显示到了前台，该控件才会被创建。
只有当surfaceView被创建了，才把相机所捕获到的数据输出给它。
如果activity回到回台。surfaceview又会被销毁
注意：在拍照的时候相机是被占用的。拍照之后需要重新预览。

练习：

package com.shellway.takephoto;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

import android.support.v7.app.ActionBarActivity;
import android.hardware.Camera;
import android.hardware.Camera.Parameters;
import android.hardware.Camera.PictureCallback;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.view.SurfaceHolder;
import android.view.SurfaceHolder.Callback;
import android.view.SurfaceView;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;

public class MainActivity extends ActionBarActivity {

    private SurfaceView surfaceview;
    private Camera camera;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //请求窗体特征：设置不显示标题，注意要在setContentView之前设置
        requestWindowFeature(Window.FEATURE_NO_TITLE);
        setContentView(R.layout.activity_main);
        //设置全屏幕显示
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
                             WindowManager.LayoutParams.FLAG_FULLSCREEN);
        surfaceview = (SurfaceView) findViewById(R.id.surfaceview);
        SurfaceHolder holder = surfaceview.getHolder();
        //设置屏幕分辨率
        holder.setFixedSize(176, 144);
        //设置屏幕保持高亮
        holder.setKeepScreenOn(true);
        holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        holder.addCallback(new MySurfaceCallback());

    }
    
    private class MySurfaceCallback implements Callback{

        @Override
        public void surfaceCreated(SurfaceHolder holder) {
            // TODO Auto-generated method stub
            try {
                //打开相机
                camera = Camera.open();
                Parameters params = camera.getParameters();
                //设置照片的尺寸
                params.setPictureSize(800, 480);
                //设置预览帧数，为了兼容2.3以前版本还是加上好
                params.setPreviewFrameRate(5);
                //设置照片质量
                params.setJpegQuality(80);
                camera.setParameters(params);
                //设置预览显示
                camera.setPreviewDisplay(surfaceview.getHolder());
                //设置开始预览
                camera.startPreview();
            } catch (Exception e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }

        @Override
        public void surfaceChanged(SurfaceHolder holder, int format, int width,
                int height) {
            // TODO Auto-generated method stub
        }

        @Override
        public void surfaceDestroyed(SurfaceHolder holder) {
            // TODO Auto-generated method stub
            //释放相机资源
            if (camera != null) {
                camera.release();
                camera = null;
            }
        }
        
    }
    
    public void takephoto(View view){
        //参数：shutter 开门被按下, raw 相机所捕获的原始数据, jpeg 相机处理的数据
        camera.takePicture(null, null, new MyPictureCallback());
    }
    
    private class MyPictureCallback implements PictureCallback{

        @Override
        public void onPictureTaken(byte[] data, Camera camera) {
            // TODO Auto-generated method stub
            try {
                File file = new File(Environment.getExternalStorageDirectory(),System.currentTimeMillis()+".jpg");
                FileOutputStream fos = new FileOutputStream(file);
                fos.write(data);
                //记得拍照存完数据到存储卡后还要给相机设置继续预览
                camera.startPreview();
            } catch (Exception e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
    }
    
    public void autofocus(View view){
        //这里是由相机硬件为我们自动对焦
    }
    
    @Override
    protected void onDestroy() {
        // TODO Auto-generated method stub
        super.onDestroy();
        if (camera != null) {
            camera.release();
            camera = null;
        }
    }
}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.shellway.takephoto.MainActivity" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" />
    
    <SurfaceView 
        android:id="@+id/surfaceview"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        />
    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        >
        <Button 
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginRight="10dp"
            android:onClick="autofocus"
            android:text="对焦"
            ></Button>
        <Button 
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginRight="10dp"
            android:text="拍照"
            android:onClick="takephoto"
            ></Button>
        
    </LinearLayout>


</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.shellway.takephoto"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="21" />
    <!-- 获取相机的拍照权限 -->
    <uses-permission android:name="android.permission.CAMERA"/>
    <!-- 获取外存储设备的写权限 -->
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/>
    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <!-- 设置横屏显示属性 screenOrientation-->
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" android:screenOrientation="landscape">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

运行结果截图：下图是在真实手机上运行的截图

 四、视频刻录

查看Android API文档可以看到MediaRecoder状态转换图，用它来实现视频的刻录：

package com.shellway.videorecoder;

import java.io.File;
import java.io.IOException;

import android.support.v7.app.ActionBarActivity;
import android.media.MediaRecorder;
import android.os.Bundle;
import android.os.Environment;
import android.view.Menu;
import android.view.MenuItem;
import android.view.Surface;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.widget.Button;

public class MainActivity extends ActionBarActivity {
    //声明一个媒体刻录机
    private MediaRecorder mr;
    //因为是动态视图，可以用SurfaceView来展示
    private SurfaceView surfaceview;
    private Button bt_start;
    private Button bt_stop;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        surfaceview = (SurfaceView) findViewById(R.id.surfaceview);
        SurfaceHolder holder = surfaceview.getHolder();
        //设置屏幕分辨率
        holder.setFixedSize(176, 144);
        //设置屏幕保持高亮
        holder.setKeepScreenOn(true);
        holder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
        bt_start = (Button) findViewById(R.id.bt_start);
        bt_stop = (Button) findViewById(R.id.bt_stop);
    }
    
    public void start(View view){
        try {
            //创建一个媒体刻录机
            mr = new MediaRecorder();
            //在给刻录机设置属性前首先要重置一下
            mr.reset();
            //设置音频、视频来源
            mr.setAudioSource(MediaRecorder.AudioSource.MIC);
            mr.setVideoSource(MediaRecorder.VideoSource.CAMERA);
            //设置音频、视频输出格式
            mr.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
            //设置音频、视频的编码
            mr.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
            mr.setVideoEncoder(MediaRecorder.VideoEncoder.H264);
            //创建一个输出音频、视频的文件
            File file = new File(Environment.getExternalStorageDirectory(),
                                        System.currentTimeMillis()+".3gp");
            mr.setOutputFile(file.getAbsolutePath());
            //设置预览
            mr.setPreviewDisplay(surfaceview.getHolder().getSurface());
            //准备刻录
            mr.prepare();
            //开始刻录
            mr.start();
            //开始刻录后，按钮可见的转变
            bt_start.setEnabled(false);
            bt_stop.setEnabled(true);
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    
    public void stop(View view){
        //停止刻录
        mr.stop();
        //停止刻录后，按钮可见的转变
        bt_start.setEnabled(true);
        bt_stop.setEnabled(false);
        //释放资源
        mr.release();
        mr = null;
    }
}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.shellway.videorecoder.MainActivity" >

    <SurfaceView 
        android:id="@+id/surfaceview"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        />
    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentRight="true"
        >
        <Button 
            android:id="@+id/bt_start"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginRight="10dp"
            android:onClick="start"
            android:text="开始"
            ></Button>
        <Button 
            android:id="@+id/bt_stop"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginRight="10dp"
            android:onClick="stop"
            android:enabled="false"
            android:text="停止"
            ></Button>
        
    </LinearLayout>

</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.shellway.videorecoder"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="21" />
    <!-- 使用相机的权限 -->
    <uses-permission android:name="android.permission.CAMERA"/>
    <!-- 媒体刻录机的权限 -->
    <uses-permission android:name="android.permission.RECORD_AUDIO"/>
    <!-- 外存储写的权限 -->
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/>
    
    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <!-- 设置一开始就横屏显示 -->
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" android:screenOrientation="landscape">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

运行结果截图：

五：手势识别
首先，使用系统给出的应用Gestures Builder画出手势库，然后把手势库导出到桌面，最后在工程res目录下
新建一个raw文件(这个文件表示原文件，编译的时候不会对它做任何修改)，我这里画的一个打勾和“Z”字母，
打勾表示拨打电话号码为5556的电话，“Z”字母表示退出本应用程序。

练习：

package com.shellway.gestures;

import java.util.ArrayList;

import android.support.v7.app.ActionBarActivity;
import android.R.anim;
import android.content.Intent;
import android.gesture.Gesture;
import android.gesture.GestureLibraries;
import android.gesture.GestureLibrary;
import android.gesture.GestureOverlayView;
import android.gesture.GestureOverlayView.OnGesturePerformedListener;
import android.gesture.Prediction;
import android.net.Uri;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Toast;

public class MainActivity extends ActionBarActivity {

    private GestureOverlayView gov;
    private GestureLibrary library;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        gov = (GestureOverlayView) findViewById(R.id.gov_id);
        //加载监听
        gov.addOnGesturePerformedListener(new MyOnGesturePerformedListener());
        //加载手势库
        library = GestureLibraries.fromRawResource(this, R.raw.gestures);
        library.load();
    }
    
    private class MyOnGesturePerformedListener implements OnGesturePerformedListener{

        @Override
        public void onGesturePerformed(GestureOverlayView overlay,
                Gesture gesture) {
            // 识别手势
            ArrayList<Prediction> predictions = library.recognize(gesture);
            if (predictions.isEmpty()) {
                Toast.makeText(getApplicationContext(),"手势不存在", Toast.LENGTH_SHORT).show();
            }else{
                //拿到手势库里面的第一个，即最匹配的手势
                Prediction prediction = predictions.get(0);
                //给匹配度打分，分是从0-10
                double score  = prediction.score;
                if (score>=6) {
                    //手势的名字
                    String name = prediction.name;
                    if (name.equals("call")) {
                        Intent intent  = new Intent();
                        intent.setAction(Intent.ACTION_CALL);
                        intent.setData(Uri.parse("tel:"+5556));
                        startActivity(intent);
                    }else if(name.equals("exit")){
                        //利用杀死进程的方法退出程序
                        android.os.Process.killProcess(android.os.Process.myPid());
                    }
                }else{
                    Toast.makeText(getApplicationContext(),"匹配度太低", Toast.LENGTH_SHORT).show();
                }
            }
        }
    }
}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
       >
    <android.gesture.GestureOverlayView 
                  android:id="@+id/gov_id"
                  android:layout_width="fill_parent"
                  android:layout_height="0dp"
                  android:layout_weight="1"
        ></android.gesture.GestureOverlayView>
    
    <LinearLayout 
          android:layout_width="fill_parent"
          android:layout_height="wrap_content"
          android:orientation="horizontal"
        >
          <Button 
              android:layout_width="0dp"
              android:layout_height="wrap_content"
              android:layout_weight="1"
              android:text="确定"
              />
          <Button 
              android:layout_width="0dp"
              android:layout_height="wrap_content"
              android:layout_weight="1"
              android:text="取消"
              />
    </LinearLayout>

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.shellway.gestures"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="21" />
    <!-- 拨打电话权限 -->
    <uses-permission android:name="android.permission.CALL_PHONE"/>
    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

运行结果截图：

可以支持多笔手势：需要做如下改动

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
       >
    <!-- 要支持多笔手势就要加上gestureStrokeType这个属性，因为默认是单笔手势 -->
    <android.gesture.GestureOverlayView 
                  android:id="@+id/gov_id"
                  android:layout_width="fill_parent"
                  android:layout_height="0dp"
                  android:layout_weight="1"
                  android:gestureStrokeType="multiple"
        ></android.gesture.GestureOverlayView>
    
    <LinearLayout 
          android:layout_width="fill_parent"
          android:layout_height="wrap_content"
          android:orientation="horizontal"
        >
          <Button 
              android:layout_width="0dp"
              android:layout_height="wrap_content"
              android:layout_weight="1"
              android:onClick="ok"
              android:text="确定"
              />
          <Button 
              android:layout_width="0dp"
              android:layout_height="wrap_content"
              android:layout_weight="1"
              android:onClick="cancel"
              android:text="取消"
              />
    </LinearLayout>

</LinearLayout>

package com.shellway.gestures;

import java.util.ArrayList;

import android.support.v7.app.ActionBarActivity;
import android.R.anim;
import android.content.Intent;
import android.gesture.Gesture;
import android.gesture.GestureLibraries;
import android.gesture.GestureLibrary;
import android.gesture.GestureOverlayView;
import android.gesture.GestureOverlayView.OnGestureListener;
import android.gesture.GestureOverlayView.OnGesturePerformedListener;
import android.gesture.Prediction;
import android.net.Uri;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Toast;

public class MainActivity extends ActionBarActivity {

    private GestureOverlayView gov;
    private GestureLibrary library;
    private Gesture gesture;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        gov = (GestureOverlayView) findViewById(R.id.gov_id);
        //加载监听
    //  gov.addOnGesturePerformedListener(new MyOnGesturePerformedListener());
        //这个是支持多笔手势的监听
        gov.addOnGestureListener(new MyOnGestureListener());
        //加载手势库
        library = GestureLibraries.fromRawResource(this, R.raw.gestures);
        library.load();
    }
    
    private class MyOnGestureListener implements OnGestureListener{

        @Override
        public void onGestureStarted(GestureOverlayView overlay,
                MotionEvent event) {
            // TODO Auto-generated method stub
            Log.i("i", " onGestureStarted ");
        }

        @Override
        public void onGesture(GestureOverlayView overlay, MotionEvent event) {
            // TODO Auto-generated method stub
            Log.i("i", " onGesture ");
        }

        @Override
        public void onGestureEnded(GestureOverlayView overlay, MotionEvent event) {
            // TODO Auto-generated method stub
            Log.i("i", " onGestureEnded ");
            //拿到当前的手势
            gesture = overlay.getGesture();
        }

        @Override
        public void onGestureCancelled(GestureOverlayView overlay,
                MotionEvent event) {
            // TODO Auto-generated method stub
            Log.i("i", " onGestureCancelled ");
        }
        
    }
    
    private class MyOnGesturePerformedListener implements OnGesturePerformedListener{

        @Override
        public void onGesturePerformed(GestureOverlayView overlay,
                Gesture gesture) {
            //overlay：表示当前的手势，gesture表示最后的手势
            recognize(gesture);
        }
    }
    
    public void ok(View view){
        recognize(gesture);
        gov.clear(true);
    }
    
    public void cancel(View view){
        gov.clear(true);
    }
    
    // 识别手势
    private void recognize(Gesture gesture) {
        ArrayList<Prediction> predictions = library.recognize(gesture);
        if (predictions.isEmpty()) {
            Toast.makeText(getApplicationContext(),"手势不存在", Toast.LENGTH_SHORT).show();
        }else{
            //拿到手势库里面的第一个，即最匹配的手势
            Prediction prediction = predictions.get(0);
            //给匹配度打分，分是从0-10
            double score  = prediction.score;
            if (score>=6) {
                //手势的名字
                String name = prediction.name;
                if (name.equals("call")) {
                    Intent intent  = new Intent();
                    intent.setAction(Intent.ACTION_CALL);
                    intent.setData(Uri.parse("tel:"+5556));
                    startActivity(intent);
                }else if(name.equals("exit")){
                    //利用杀死进程的方法退出程序
                    android.os.Process.killProcess(android.os.Process.myPid());
                }
            }else{
                Toast.makeText(getApplicationContext(),"匹配度太低", Toast.LENGTH_SHORT).show();
            }
        }
    }
}

多笔手势监听方法的测试：

 

八、通知：Notification
之前我们学了提示用户的两种方式：Toast 、AlertDialog
现在我们来看看通知Noitification,它主要由以下六部分组成：
图标、ticker提示信息、时间、标题、内容、事件

练习：

package com.shellway.notification;

import android.support.v7.app.ActionBarActivity;
import android.R.anim;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.RemoteViews;

public class MainActivity extends ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }
    
    public void notification(View view){
        //得到通知管理器
        NotificationManager notificationManager = 
                     (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        //构建通知
        Notification notification = new Notification(android.R.drawable.stat_notify_chat,
                                               "这是一个提示信息", System.currentTimeMillis());
        //通知的点击事件
        Intent intent = new Intent(this,MainActivity.class);
        //第二个参数为请求码，可随意指定。第四个参数为标志码，我们这里填0就可以了
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 100, intent, 0);
        notification.setLatestEventInfo(this, "通知标题", "通知内容", pendingIntent);
        //点击后消失
        notification.flags = Notification.FLAG_AUTO_CANCEL;
        //发送通知
        notificationManager.notify(100, notification);
    }
    
    public void customnotification(View view){
        //得到通知管理器
        NotificationManager notificationManager = 
                    (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        //构建通知
        Notification notification = new Notification();
        notification.icon = android.R.drawable.stat_notify_call_mute;//图标
        notification.tickerText  = "新的信息来啦";//通知提示信息
        //自定义通知内容布局
        RemoteViews remoteviews = new RemoteViews(getPackageName(), R.layout.contentview);
        notification.contentView = remoteviews;
        //定义通知内容
        Intent intent = new Intent(this,MainActivity.class);
        PendingIntent paIntent = PendingIntent.getActivity(this, 100, intent, 0);
        notification.contentIntent = paIntent;
        //点击后消失
        notification.flags = Notification.FLAG_AUTO_CANCEL;
        //发送通知
        notificationManager.notify(100, notification);
        
    }
}

package com.shellway.notification;

import android.app.Activity;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;

public class OtherActivity extends ActionBarActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.contentview);
    }
}

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    >

    <Button 
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="notification"
        android:text="普通通知"
        />
    
    <Button 
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="customnotification"
        android:text="自定义通知"
        />

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="horizontal" >
    
    <ImageView 
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_launcher"
        />
    <LinearLayout
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        >
        <TextView 
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:text="新收到10条短信"
            />
        <ProgressBar
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            style="@android:style/Widget.ProgressBar.Horizontal"
            ></ProgressBar>
    </LinearLayout>
      
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.shellway.notification"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="21" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name=".OtherActivity"></activity>
    </application>

</manifest>

运行结果截图：

 九、动画(Animation)

我们可以查官方文档中API Guies可以看到

根据它，我们可以进行以上提到的两种动画的开发工作
练习1：tween动画,首先在res目录下新建文件夹anim，然后在其下面建立动画xml文件

package com.example.tweenanimation;

import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.ImageView;

public class MainActivity extends ActionBarActivity {

    private ImageView iv;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        iv = (ImageView) findViewById(R.id.iv);
    }

     public void start(View view){
         //加载动画
   //      Animation anim = AnimationUtils.loadAnimation(this, R.anim.alpha);//图片透明度
   //      Animation anim = AnimationUtils.loadAnimation(this, R.anim.scale);//图片缩放
   //      Animation anim = AnimationUtils.loadAnimation(this, R.anim.translate);//图片移动
   //      Animation anim = AnimationUtils.loadAnimation(this, R.anim.rotate);//图片旋转
         Animation anim = AnimationUtils.loadAnimation(this, R.anim.set);//以上综合
         //执行动画
         iv.startAnimation(anim);
     }
}

<?xml version="1.0" encoding="utf-8"?>
<!-- FillAfter,动画的最后一帧是否保持在View上面，FillEnabled是否启用Fill保持  -->
<alpha xmlns:android="http://schemas.android.com/apk/res/android"
    android:fromAlpha="1"
    android:toAlpha="0"
    android:duration="2000"
    android:fillAfter="true"
    >
    
</alpha>

<?xml version="1.0" encoding="utf-8"?>
<!-- pivotX 若填5表示旋转5个像素， 若填5%表示相对自身旋转5%，若填5%p表示相对父元素旋转-->
<rotate xmlns:android="http://schemas.android.com/apk/res/android"
    android:fromDegrees="0"
    android:toDegrees="90"
    android:pivotX="50%"
    android:pivotY="50%"
    android:duration="2000"
    >
    
</rotate>

<?xml version="1.0" encoding="utf-8"?>
<!-- FillAfter,动画的最后一帧是否保持在View上面，FillEnabled是否启用Fill保持 -->
<scale xmlns:android="http://schemas.android.com/apk/res/android"
    android:fromXScale="1"
    android:toXScale="2"
    android:fromYScale="1"
    android:toYScale="0.5"
    android:duration="2000"
    android:fillAfter="true"
    >

</scale>

<?xml version="1.0" encoding="utf-8"?>
<translate xmlns:android="http://schemas.android.com/apk/res/android"
    android:fromXDelta="0"
    android:toXDelta="100"
    android:fromYDelta="0"
    android:toYDelta="100"
    android:fillAfter="true"
    android:duration="2000"
    >
    
</translate>

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android">
    <alpha 
    android:fromAlpha="1"
    android:toAlpha="0"
    android:duration="2000"
    android:fillAfter="true"
    />
    <scale 
    android:fromXScale="1"
    android:toXScale="2"
    android:fromYScale="1"
    android:toYScale="0.5"
    android:duration="2000"
    android:fillAfter="true"
    />
    <translate 
    android:fromXDelta="0"
    android:toXDelta="100"
    android:fromYDelta="0"
    android:toYDelta="100"
    android:fillAfter="true"
    android:duration="2000"
    />
    <rotate
    android:fromDegrees="0"
    android:toDegrees="90"
    android:pivotX="50%"
    android:pivotY="50%"
    android:duration="2000"
    />

</set>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
     >
     
    <ImageView 
        android:id="@+id/iv"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:src="@drawable/ic_launcher"
        />

    <Button 
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="start"
        android:text="开始"
        />

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.tweenanimation"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="21" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

练习2：frame动画，首先在res目录下新建drawable文件夹，然后在其下加入要用到的图片资源和资源xml文件

package comshellway.frameanimation;

import android.support.v7.app.ActionBarActivity;
import android.graphics.drawable.AnimationDrawable;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.ImageView;

public class MainActivity extends ActionBarActivity {
    private AnimationDrawable ad;
    private ImageView iv;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        iv = (ImageView) findViewById(R.id.iv);
    }
    
    //开始动画
    public void start(View view){
        //一般frame动画用来作背景用，在这里是得到背景动画
        ad = (AnimationDrawable) iv.getBackground();
        ad.start();
    }
    
    //停止动画
    public void stop(View view){
        ad.stop();
    }
}

<?xml version="1.0" encoding="utf-8"?>
<animation-list xmlns:android="http://schemas.android.com/apk/res/android" android:oneshot="true" >
     <item
        android:drawable="@drawable/a1"
        android:duration="200" />
     <item
        android:drawable="@drawable/a2"
        android:duration="200" />
     <item
        android:drawable="@drawable/a3"
        android:duration="200" />
     <item
        android:drawable="@drawable/a4"
        android:duration="200" />
     <item
        android:drawable="@drawable/a5"
        android:duration="200" />
     <item
        android:drawable="@drawable/a6"
        android:duration="200" />
     <item
        android:drawable="@drawable/a7"
        android:duration="200" />
     <item
        android:drawable="@drawable/a8"
        android:duration="200" />
     <item
        android:drawable="@drawable/a9"
        android:duration="200" />
     <item
        android:drawable="@drawable/a10"
        android:duration="200" />
     <item
        android:drawable="@drawable/a11"
        android:duration="200" />
     <item
        android:drawable="@drawable/a12"
        android:duration="200" />
     <item
        android:drawable="@drawable/a13"
        android:duration="200" />
     <item
        android:drawable="@drawable/a14"
        android:duration="200" />
     <item
        android:drawable="@drawable/a15"
        android:duration="200" />

</animation-list>

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    >
  <ImageView 
      android:id="@+id/iv"
      android:layout_width="fill_parent"
      android:layout_height="wrap_content"
      android:background="@drawable/frame"
      />
    <Button 
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="start"
        android:text="开始"
        />
    <Button 
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="stop"
        android:text="停止"
        />

</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="comshellway.frameanimation"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="21" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

运行结果截图：

 十、传感器

练习：

package com.shellway.sensor;

import android.support.v7.app.ActionBarActivity;
import android.content.Context;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.animation.Animation;
import android.view.animation.RotateAnimation;
import android.widget.ImageView;

public class MainActivity extends ActionBarActivity {
    private MySensorEventListener listener;
    private SensorManager sensorManager;
    private Sensor sensor;
    private ImageView iv;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        iv = (ImageView) findViewById(R.id.iv);
        //获得传感器管理器
        sensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
        //获得方向传感器
        sensor = sensorManager.getDefaultSensor(Sensor.TYPE_ORIENTATION);
        listener = new MySensorEventListener();
    }
    
    @Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onResume();
        //注册sensor监听
        sensorManager.registerListener(listener, sensor, SensorManager.SENSOR_DELAY_GAME);
    }
    
    private class MySensorEventListener implements SensorEventListener{
        private float predegree = 0;
        @Override
        public void onSensorChanged(SensorEvent event) {
            // TODO Auto-generated method stub
            float x = event.values[SensorManager.DATA_X];
            //创建一个旋转的动画，0.5f表示自身的正中间，Animation.RELATIVE_TO_SELF表示相对自身旋转
            RotateAnimation rotate = new RotateAnimation(-predegree, x, 
                                      Animation.RELATIVE_TO_SELF, 0.5f,
                                      Animation.RELATIVE_TO_SELF, 0.5f);
            rotate.setDuration(50);
            iv.startAnimation(rotate);
            predegree = x;
        }
  
        //精确度的改变，这里暂时不用管
        public void onAccuracyChanged(Sensor sensor, int accuracy) {
            // TODO Auto-generated method stub
            
        }
    }
    
    @Override
    protected void onPause() {
        // TODO Auto-generated method stub
        super.onPause();
        //当应用在前台不活动的时候取消监听
        sensorManager.unregisterListener(listener);
    }
}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.shellway.sensor.MainActivity" >

    <ImageView 
        android:id="@+id/iv"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerInParent="true"
        android:src="@drawable/zn"
        />

</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.shellway.sensor"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="21" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

运行结果截图：

十一：图片的移动和缩放

分析：

练习：

package com.shellway.dragscale;

import android.support.v7.app.ActionBarActivity;
import android.graphics.Matrix;
import android.graphics.PointF;
import android.os.Bundle;
import android.util.FloatMath;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.ImageView;

public class MainActivity extends ActionBarActivity {

    private ImageView iv;
    private MyOnTouchListener listener;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        listener = new MyOnTouchListener();
        
        iv = (ImageView) findViewById(R.id.iv);
        iv.setOnTouchListener(listener);
    }
    
    private class MyOnTouchListener implements OnTouchListener{
        private PointF startPiont = new PointF();//起始点
        private Matrix mcurrentMatrix = new Matrix();//图片当前的matrix值
        private Matrix mMatrix = new Matrix();//来一个临时的matrix
        
        private int type = 0;
        private final static int DRAG = 1;
        private final static int SCALE = 2;
        private PointF mstartP;//中心点
        private float mdistance;//两点间的距离
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            
            int action = event.getAction()&MotionEvent.ACTION_MASK;
            switch (action) {
            case MotionEvent.ACTION_DOWN://当手指按下
                float x = event.getX();
                float y = event.getY();
                startPiont.set(x, y);//
                mcurrentMatrix.set(iv.getImageMatrix());//图片还没有被拖动时候的位置
                type = DRAG;
                break;
            case MotionEvent.ACTION_POINTER_1_DOWN://屏幕上已经有一根手指，再按下一根手指
                mcurrentMatrix.set(iv.getImageMatrix());//图片还没有被缩放时候的大小
                mstartP = getMidPoint(event);//得到移动前两个手指间的中心位置
                mdistance = getMidDistance(event);//得到移动前两个手指间的距离
                type = SCALE;
                break;
            case MotionEvent.ACTION_MOVE://当手指移动
                if (type == DRAG) {
                    mMatrix.set(mcurrentMatrix);
                    float dx = event.getX() - startPiont.x;
                    float dy = event.getY() - startPiont.y;
                    mMatrix.postTranslate(dx, dy);
                }else if(type == SCALE){
                    mMatrix.set(mcurrentMatrix);
                    float distance = getMidDistance(event);//得到移动后两个手指间的距离
                    float sx = distance/mdistance;
                    mMatrix.postScale(sx, sx, mstartP.x, mstartP.y);
                }
                break;
            case MotionEvent.ACTION_UP://当手指弹起
            case MotionEvent.ACTION_POINTER_1_UP://屏幕上弹起一根手指，还有一根手指
                type = 0;
                break;

            default:
                break;
            }
            //给界面设置变动后的数据
            iv.setImageMatrix(mMatrix);
            return true;
        }
        
        //计算中心点位置
        public PointF getMidPoint(MotionEvent event){
            float x = (event.getX(1) + event.getX(0))/2;
            float y = (event.getY(1) + event.getY(0))/2;
            return new PointF(x,y);
        }
        
        //计算两点间的距离
        public float getMidDistance(MotionEvent event){
            float dx = event.getX(1) - event.getX(0);
            float dy = event.getY(1) - event.getY(0);
            return FloatMath.sqrt((dx*dx) + (dy*dy));
        }
    }
}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.shellway.dragscale.MainActivity" >
    <!--scaleType表示缩放类型， matrix表示图片的位置和大小 -->
    <ImageView 
        android:id="@+id/iv"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:scaleType="matrix"
        android:src="@drawable/family"
        />

</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.shellway.dragscale"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="21" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

运行结果截图：