Android学习笔记——Layout
下面列举了Android中Layout，Table，Menu，Checkbox，Listview，Button，Bundle的基本使用和demo
1.Layout：该工程的功能是实现LinearLayout
Android Layout有多种，比如：Layout，MixLayout，TableLayout等
以下的代码是MainActivity.java中的代码
package com.example.linearlayout;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;
public class MainActivity extends Activity {
private TextView firstText;
private TextView secondText;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
firstText = (TextView)findViewById(R.id.firstText);
secondText = (TextView)findViewById(R.id.secondText);
firstText.setText(R.string.firstText);
secondText.setText(R.string.secondText);
}
}
以下的代码是activity_main.xml中的代码
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/LinearLayout1"
android:layout_width="fill_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="${relativePackage}.${activityClass}" >
<!--
android:id 为控件制定相应的ID
android:text 指定控件当中显示的文字
android:gravity 指定控件的基本位置/居中居右等
android:textSize 指定控件的基本位置/居中居右等
android:background 指定该控件所使用的背景色，RGB命名法
android:width 指定控件的宽度
android:height 指定控件的高度
android:padding 指定控件的内边距
android:weight 数字为相应的比例
android:singleLine 设定true为同一行显示
-->
<TextView
android:id="@+id/firstText"
android:gravity="center_vertical"
android:textSize="20pt"
android:background="#0000ff"
android:layout_width="fill_parent"
android:layout_height="0.0dip"
android:paddingLeft="10dip"
android:paddingTop="20dip"
android:paddingRight="30dip"
android:paddingBottom="40dip"
android:layout_weight="1"
android:singleLine="true"
/>
<TextView
android:id="@+id/secondText"
android:gravity="center_vertical"
android:textSize="15pt"
android:background="#00ff00"
android:layout_width="fill_parent"
android:layout_height="0.0dip"
android:paddingLeft="10dip"
android:paddingTop="20dip"
android:paddingRight="30dip"
android:paddingBottom="40dip"
android:layout_weight="2"
android:singleLine="true"
/>
</LinearLayout>
以下的代码是string.xml中的代码
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">LinearLayout</string>
<string name="hello_world">Hello world!</string>
<string name="firstText">第一行</string>
<string name="secondText">第二行</string>
</resources>
2.Layout：该工程的功能是实现LinearLayout+TableLayout
以下代码是MainActivity.java中的代码
package com.example.mixlayout;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;
public class MainActivity extends Activity {
private TextView firstText;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
}
以下代码是activity_main.xml中的代码
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/LinearLayout1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
tools:context="${relativePackage}.${activityClass}" >
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1"
android:orientation="horizontal" >
<TextView
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:layout_weight="1"
android:background="#aa0000"
android:gravity="center_horizontal"
android:text="red" />
<TextView
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:layout_weight="1"
android:background="#00aa00"
android:gravity="center_horizontal"
android:text="green" />
<TextView
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:layout_weight="1"
android:background="#0000aa"
android:gravity="center_horizontal"
android:text="blue" />
</LinearLayout>
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_weight="1"
android:orientation="horizontal" >
<TableLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:stretchColumns="1">
<TableRow>
<TextView
android:padding="3dip"
android:text="row1_column1" />
<TextView
android:gravity="center_horizontal"
android:padding="3dip"
android:text="row1_column2" />
<TextView
android:gravity="right"
android:padding="3dip"
android:text="row1_column3" />
</TableRow>
<TableRow>
<TextView
android:padding="3dip"
android:text="row2_column1" />
<TextView
android:gravity="center_horizontal"
android:padding="3dip"
android:text="row2_column2" />
<TextView
android:gravity="right"
android:padding="3dip"
android:text="row2_column3" />
</TableRow>
</TableLayout>
</LinearLayout>
</LinearLayout>
3.Table：该工程的功能是实现在一个activity中显示一个表格
以下代码是MainActivity.java中的代码
package com.example.tablelayout;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
}
以下的代码是activity_main.xml中的代码
<TableLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/TableLayout1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:stretchColumns="1"
tools:context="${relativePackage}.${activityClass}" >
<!-- 由于fill_parent不能填满，所以stretchColumns指定列拉伸 -->
<TableRow>
<TextView
android:text="@string/hello_world"
android:padding="3dip"
android:background="#aa0000" />
<TextView
android:text="@string/hello_world"
android:padding="3dip"
android:background="#00aa00"
android:gravity="center_horizontal" />
<TextView
android:text="@string/hello_world"
android:padding="3dip"
android:background="#0000aa"
android:gravity="right" />
</TableRow>
<TableRow>
<TextView
android:text="@string/hello_world"
android:padding="3dip" />
<TextView
android:text="@string/hello_world"
android:padding="3dip"
android:gravity="right" />
</TableRow>
</TableLayout>
4.Menu：该工程的功能是实现两个数相乘，并在另外一个Activity中显示计算的结果
以下的代码是MainActivity.java中的代码
package com.example.menu;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends Activity {
private EditText factorOne;
private EditText factorTwo;
private TextView symbol;
private Button calculate;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
factorOne = (EditText)findViewById(R.id.factorOne);
factorTwo = (EditText)findViewById(R.id.factorTwo);
symbol = (TextView)findViewById(R.id.symbol);
calculate = (Button)findViewById(R.id.calculate);
//symbol.setText("乘以");
//calculate.setText("计算");
//为symbol和calculate设置显示的值
symbol.setText(R.string.symbol);
calculate.setText(R.string.calculate);
//将监听器的对象绑定到按钮对象上面
calculate.setOnClickListener(new CalculateListener());
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// TODO Auto-generated method stub
menu.add(0,1,1,R.string.exit);
menu.add(0,2,2,R.string.about);
return super.onCreateOptionsMenu(menu);
}
//当客户点击MENU按钮的时候，调用该方法
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// TODO Auto-generated method stub
if(item.getItemId() == 1){
finish();
}
return super.onOptionsItemSelected(item);
}
class CalculateListener implements OnClickListener{
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
//取得两个EditText控件的值
String factorOneStr = factorOne.getText().toString();
String factorTwoStr = factorTwo.getText().toString();
//将这两个值存放到Intent对象当中
Intent intent = new Intent();
intent.putExtra("one",factorOneStr);
intent.putExtra("two",factorTwoStr);
intent.setClass(MainActivity.this,ResultActivity.class );
//使用这个Intent对象来启动ResultActivity
MainActivity.this.startActivity(intent);
}
}
}
以下的代码是ResultActivity.java中的代码
package com.example.menu;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;
public class ResultActivity extends Activity{
private TextView resultView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_result);
resultView = (TextView)findViewById(R.id.result);
//得到Intent对象当中的值
Intent intent = getIntent();
String factorOneStr = intent.getStringExtra("one");
String factorTwoStr = intent.getStringExtra("two");
int factorOneInt = Integer.parseInt(factorOneStr);
int factorTwoInt = Integer.parseInt(factorTwoStr);
//计算两个值的积
int result = factorOneInt * factorTwoInt;
resultView.setText(result + "");
}
}
以下的代码是activity_main.xml中的代码
<?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="vertical" >
<EditText
android:id="@+id/factorOne"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
<TextView
android:id="@+id/symbol"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
<EditText
android:id="@+id/factorTwo"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
<Button
android:id="@+id/calculate"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
</LinearLayout>
以下的代码是activity_result.xml中的代码
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:id="@+id/result"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
</LinearLayout>
以下的代码是string.xml中的代码
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">menu</string>
<string name="hello_world">Hello world!</string>
<string name="resultLabel">result</string>
<string name="symbol">乘法</string>
<string name="calculate">计算</string>
<string name="exit">退出</string>
<string name="about">关于</string>
</resources>
以下的代码是AndroidManifest.xml中的代码
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.menu"
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 = ".ResultActivity">
</activity>
</application>
</manifest>
5.checkbox：该工程的功能实现在一个activity中显示一个单选框和一个多选框
以下代码是MainActivity.java文件中的代码
package com.example.checkbox;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.Toast;
public class MainActivity extends Activity {
//对控件对象进行声明
private RadioGroup gendergroup = null;
private RadioButton femaleButton = null;
private RadioButton maleButton = null;
private CheckBox swimBox = null;
private CheckBox runBox = null;
private CheckBox readBox = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//通过控件的ID来得到代表控件的对象
gendergroup = (RadioGroup)findViewById(R.id.genderGroup);
femaleButton = (RadioButton)findViewById(R.id.femaleButton);
maleButton = (RadioButton)findViewById(R.id.maleButton);
swimBox = (CheckBox)findViewById(R.id.swim);
runBox = (CheckBox)findViewById(R.id.run);
readBox = (CheckBox)findViewById(R.id.read);
//设置监听器
gendergroup.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
// TODO Auto-generated method stub
if(femaleButton.getId() == checkedId){
System.out.println("female");
Toast.makeText(MainActivity.this, "female", Toast.LENGTH_SHORT).show();
}
else if(maleButton.getId() == checkedId)
{
System.out.println("male");
Toast.makeText(MainActivity.this, "male", Toast.LENGTH_SHORT).show();
}
}
});
//为多选按钮添加监听器
swimBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// TODO Auto-generated method stub
if(isChecked)
{
System.out.println("swim is checked");
}
else
{
System.out.println("swim is unchecked");
}
}
});
runBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// TODO Auto-generated method stub
if(isChecked)
{
System.out.println("run is checked");
}
else
{
System.out.println("run is unchecked");
}
}
});
readBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// TODO Auto-generated method stub
if(isChecked)
{
System.out.println("read is checked");
}
else
{
System.out.println("read is unchecked");
}
}
});
}
}
以下代码是activity_main.xml文件中的代码
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/LinearLayout1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
tools:context="${relativePackage}.${activityClass}" >
<TextView
android:id="@+id/textView1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello_world" />
<RadioGroup
android:id="@+id/genderGroup"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
>
<RadioButton
android:id="@+id/femaleButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/female"
/>
<RadioButton
android:id="@+id/maleButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/male"
/>
</RadioGroup>
<CheckBox
android:id="@+id/swim"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/swim"
/>
<CheckBox
android:id="@+id/run"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/run"
/>
<CheckBox
android:id="@+id/read"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/read"
/>
</LinearLayout>
以下代码是string.xml文件中的代码
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">CheckBox</string>
<string name="hello_world">Hello world!</string>
<string name="female">女</string>
<string name="male">男</string>
<string name="swim">游泳</string>
<string name="run">跑步</string>
<string name="read">读书</string>
</resources>
6.listview：该工程的功能是实现在一个activity中显示一个列表
以下代码是MainActivity.java中的代码
package com.example.listview;
import java.util.ArrayList;
import java.util.HashMap;
import android.app.ListActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.SimpleAdapter;
public class MainActivity extends ListActivity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ArrayList<HashMap<String, String>> list =
new ArrayList<HashMap<String, String>>();
HashMap<String, String> map1 = new HashMap<String,String>();
HashMap<String, String> map2 = new HashMap<String,String>();
HashMap<String, String> map3 = new HashMap<String,String>();
map1.put("user_name","zhangsan");
map1.put("user_ip","192.168.0.1");
map2.put("user_name","lisi");
map2.put("user_ip","192.168.0.2");
map3.put("user_name","wangwu");
map3.put("user_ip","192.168.0.3");
list.add(map1);
list.add(map2);
list.add(map3);
SimpleAdapter listAdapter = new SimpleAdapter(this, list,
R.layout.activity_user, new String[] {"user_name", "user_ip"},
new int[] {R.id.user_name, R.id.user_ip});
setListAdapter(listAdapter);
}
}
以下的代码是activity_main.xml中的代码
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/LinearLayout1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
tools:context="${relativePackage}.${activityClass}" >
<LinearLayout
android:id="@+id/listLinearLayout"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
>
<ListView
android:id="@id/android:list"
android:scrollbars="vertical"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:drawSelectorOnTop="false"
/>
</LinearLayout>
</LinearLayout>
以下代码是activity_user.xml中的代码
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/LinearLayout2"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="horizontal"
android:paddingLeft="10dip"
android:paddingRight="10dip"
android:paddingTop="1dip"
android:paddingBottom="1dip"
tools:context="${relativePackage}.${activityClass}" >
<TextView
android:id="@+id/user_name"
android:layout_width="180dip"
android:layout_height="30dip"
android:textSize="10pt"
android:singleLine="true"
/>
<TextView
android:id="@+id/user_ip"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="right"
android:textSize="10pt"
/>
</LinearLayout>
7.Button：工程的功能是实现在一个acticity上点击按钮，切换到另外一个activity
以下代码为MainActivity.java中的代码
package com.example.button_activity;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends Activity {
private Button myButton = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
myButton = (Button)findViewById(R.id.myButton);
myButton.setOnClickListener(new MyButtonListener());
}
class MyButtonListener implements OnClickListener{
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
Intent intent = new Intent();
intent.setClass(MainActivity.this, OtherActivity.class);
MainActivity.this.startActivity(intent);
}
}
}
以下代码为OtherActivity.java中的代码
package com.example.button_activity;
import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;
public class OtherActivity extends Activity{
private TextView myTextView = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_other);
myTextView = (TextView)findViewById(R.id.myTextView);
myTextView.setText(R.string.other);
}
}
以下代码为activity_main.xml中的代码
<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"
tools:context="${relativePackage}.${activityClass}" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/hello_world" />
<Button
android:id="@+id/myButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
</RelativeLayout>
以下代码为activity_other.xml中的代码
<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"
tools:context="${relativePackage}.${activityClass}" >
<TextView
android:id="@+id/myTextView"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello_world" />
</RelativeLayout>
以下代码为string.xml中的代码
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">button_activity</string>
<string name="hello_world">Hello world!</string>
<string name="other">OtherActivity</string>
</resources>
以下代码为AndroidManifest.xml中的代码
注意修改package的名称
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.button_activity"
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"
android:label="@string/other" >
</activity>
</application>
</manifest>
如果不能运行请kill-adb和start-adb并重新启动eclipse
8.Button：该工程的功能是实现在activity中显示一个TextView和一个Button
以下代码是MainActivity中的代码
package com.example.button;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;
import android.widget.TextView;
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
TextView myTextView = (TextView)findViewById(R.id.myTextView);
Button myButton = (Button)findViewById(R.id.myButton);
myTextView.setText("我的第一个TextView");
myButton.setText("我的第一个Button");
}
}
以下代码是activity_main中的代码
<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"
tools:context="${relativePackage}.${activityClass}" >
<TextView
android:id="@+id/myTextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/hello_world" />
<Button
android:id="@+id/myButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
/>
</RelativeLayout>
该工程的功能是实现进度条的显示，按以下按钮进度条增加10%
以下代码是MainActivity.java中的代码
package com.example.progressbar;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ProgressBar;
public class MainActivity extends Activity {
//申明限量
private ProgressBar firstBar = null;
private ProgressBar secondBar = null;
private Button myButton = null;
private int i = 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//根据控件的ID来取得代表控件的对象
firstBar = (ProgressBar)findViewById(R.id.firstBar);
secondBar = (ProgressBar)findViewById(R.id.secondBar);
myButton = (Button)findViewById(R.id.myButton);
myButton.setOnClickListener(new ButtonListener());
System.out.print(firstBar.getMax());
}
class ButtonListener implements OnClickListener{
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
if(i == 0)
{
//设置进度条处于可见的状态
firstBar.setVisibility(View.VISIBLE);
secondBar.setVisibility(View.VISIBLE);
}
else if(i < firstBar.getMax())
{
//设置主进度条的当前值
firstBar.setProgress(i);
//设置第二进度条的当前值
firstBar.setSecondaryProgress(i + 10);
//因为默认的进度条无法显示进行的状态
//secondBar.setProgress(i);
}
else
{
//设置进度条处于不可见状态
firstBar.setVisibility(View.GONE);
secondBar.setVisibility(View.GONE);
}
i = i + 10;
}
}
}
以下代码是activity_main.xml中的代码
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/LinearLayout1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
tools:context="${relativePackage}.${activityClass}" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="@string/hello_world" />
<ProgressBar
android:id="@+id/firstBar"
style="?android:attr/progressBarStyleHorizontal"
android:layout_width="200dp"
android:layout_height="wrap_content"
android:visibility="gone"
/>
<ProgressBar
android:id="@+id/secondBar"
style="?android:attr/progressBarStyle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:visibility="gone"
android:max="200"
/>
<Button
android:id="@+id/myButton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="begin"
/>
</LinearLayout>
9.Bundle：该工程的功能是实现不同线程之间数据的传递
以下代码是MainActivity.java中的代码
package com.example.bundle;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.HandlerThread;
import android.os.Looper;
import android.os.Message;
import android.view.Menu;
import android.view.MenuItem;
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//打印了当前线程的ID
System.out.println("Activity-->" + Thread.currentThread().getId());
//生成一个HandleThread对象，实现了使用Looper来处理消息队列的功能，这个类由android程序框架提供
HandlerThread handlerThread = new HandlerThread("handler_thread");
//在使用HandlerThread的getLooper（）方法之前，必须先调用该类的start（）
handlerThread.start();
MyHandler myHandler = new MyHandler(handlerThread.getLooper());
Message msg = myHandler.obtainMessage();
//msg.obj="abc";
//将msg发送到目标对象，所谓的目标对象，就是生成该msg对象的handler对象
Bundle b = new Bundle();
b.putInt("age", 20);
b.putString("name", "John");
msg.setData(b);
msg.sendToTarget();
}
class MyHandler extends Handler{
public MyHandler(){
}
public MyHandler(Looper looper){
//super调用父类
super(looper);
}
public void handleMessage(Message msg){
//String s = (String)msg.obj;
Bundle b = msg.getData();
int age = b.getInt("age");
String name = b.getString("name");
System.out.println("age is " + age +", name is " + name);
System.out.println("Handler-->" + Thread.currentThread().getId());
System.out.println("handlerMessage");
}
}
}
以下代码是activity_main.xml中的代码
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/LinearLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="${relativePackage}.${activityClass}" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/hello_world" />
</LinearLayout>
10.ProcessBar：该工程的功能是实现点击按钮进度条按10%递增，使用的方式是Handler
以下的代码是MainActivity.java中的代码
package com.example.progressbarhandler;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ProgressBar;
public class MainActivity extends Activity {
//申明变量
ProgressBar bar = null;
Button startButton = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//根据空间的ID得到代表控件的对象，并未按钮去设置监听器
bar = (ProgressBar)findViewById(R.id.bar);
startButton = (Button)findViewById(R.id.startButton);
startButton.setOnClickListener(new ButtonListener());
}
class ButtonListener implements OnClickListener{
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
bar.setVisibility(View.VISIBLE);
updateBarHandler.post(updateThread);
}
}
//使用匿名内部类来复写Handler当中的handMessage方法
Handler updateBarHandler = new Handler(){
public void handleMessage(Message msg){
bar.setProgress(msg.arg1);
//线程队列
updateBarHandler.post(updateThread);
}
};
//线程类，该类使用匿名内部类的方式进行声明
Runnable updateThread = new Runnable(){
int i = 0;
public void run(){
System.out.println("Begin Thread");
i = i + 10;
//得到一个消息对象，message类是由android操作系统提供
Message msg = updateBarHandler.obtainMessage();
//将msg对象的arg1参数的值设置为i，用arg1和arg2这两个成员传递消息
msg.arg1 = i;
try{
//设置当前显示睡眠1秒
Thread.sleep(1000);
}
catch (InterruptedException e){
e.printStackTrace();
}
//将msg对象加入到消息队列当中
updateBarHandler.sendMessage(msg);
if(i == 100){
//如果当i的值为100时，就将线程对象从handle当中移除
updateBarHandler.removeCallbacks(updateThread);
}
}
};
}
以下的代码是activity_main.xml中的代码
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/LinearLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="${relativePackage}.${activityClass}" >
<ProgressBar
android:id="@+id/bar"
style="?android:attr/progressBarStyleHorizontal"
android:layout_width="200dp"
android:layout_height="wrap_content"
android:visibility="gone"
/>
<Button
android:id="@+id/startButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="start"
/>
</LinearLayout>
11.Handler：线程管理
步骤：
1. 申请一个Handler对象
Handler handler = new Handler();
2. 创建一个线程
{继承Thread类或者实现Runnable这个接口}
使用Runnable创建一个内部匿名类对象updateThread（要复写run方法）
3. 使用handler的post方法将线程加入到线程队列中
handler.post(updateThread);
4. 使用handler的removeCallbacks方法移出updateThread线程
注意：如果线程从线程队列中出来被执行后，则队列中就不在有线程
因此如果线程在被执行后没有方法将其再次加入到队列中，则无需使用removeCallbacks
线程走出线程队列有两种情况：
一种是被执行，此时要执行run方法
一种是使用removeCallbacks方法，此时线程不被执行，因此不调用run
5. 使用handler的postDelayed方法延时将线程加入到队列中
handler.postDelayed(updateThread,3000)
以下代码是MainActivity.java中的代码
package com.example.handler;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends Activity {
//声明两个按钮控件
private Button StartButton = null;
private Button EndButton = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//根据控件的ID得到代表控件的对象，并为这两个按钮设置相应的监听器
StartButton = (Button)findViewById(R.id.StartButton);
StartButton.setOnClickListener(new StartButotnListener());
EndButton = (Button)findViewById(R.id.EndButton);
EndButton.setOnClickListener(new EndButtonListener());
}
class StartButotnListener implements OnClickListener{
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
handler.post(updateThread);
}
}
class EndButtonListener implements OnClickListener{
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
handler.removeCallbacks(updateThread);
}
}
//创建一个Handler对象
Handler handler = new Handler();
//将要执行的操作下载线程对象的run方法当中
Runnable updateThread = new Runnable(){
public void run(){
System.out.println("UpdateThread");
//在run方法内部，执行postDelayed或者是post方法
handler.postDelayed(updateThread,3000);
}
};
}
以下代码是activity_main.xml中的代码
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/LinearLayout1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical"
tools:context="${relativePackage}.${activityClass}" >
<Button
android:id="@+id/StartButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Start"
/>
<Button
android:id="@+id/EndButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="End"
/>
</LinearLayout>
以下代码是MainActivity.java中的代码
package com.example.handlertest;
import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
public class MainActivity extends Activity {
private Handler handler = new Handler();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
handler.post(r);
//Thread t = new Thread(r);
//t.start();
System.out.println("activity--->"+ Thread.currentThread().getId());
System.out.println("activityname--->"+ Thread.currentThread().getName());
}
Runnable r = new Runnable(){
public void run() {
System.out.println("handler--->"+ Thread.currentThread().getId());
System.out.println("handlername--->"+ Thread.currentThread().getName());
try{
Thread.sleep(10000);
}
catch (InterruptedException e)
{
e.printStackTrace();
}
}
};
}
以下代码是activity_main.xml中的代码
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/LinearLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="${relativePackage}.${activityClass}" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/hello_world" />
</LinearLayout>
本文只发表于博客园和tonglin0325的博客，作者：tonglin0325，转载请注明原文链接：https://www.cnblogs.com/tonglin0325/p/4584181.html
