第七周作业

1.三个界面，界面1点击按钮使用显式意图开启界面2.
界面2点击按钮隐式意图开启界面3

2.在界面1做一个按钮开启浏览器访问百度

package com.example.app6;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;

public class Activity3 extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_activity3);
    }



}

package com.example.lj;

import android.net.Uri;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.util.Log;
import android.view.Menu;
import android.view.View;

public class MainActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Log.e("MainActivity", "调用oncreate");//在logcat里输出，标签为MainActivity，提示信息为调用oncreate
        
    }
   
    @Override
    protected void onStart() {
        // TODO Auto-generated method stub
        super.onStart();
        Log.e("MainActivity", "调用onstart");
    }
    @Override
    protected void onResume() {
        // TODO Auto-generated method stub
        super.onResume();
        Log.e("MainActivity", "调用onresume");
    }
    @Override
    protected void onPause() {
        // TODO Auto-generated method stub
        super.onPause();
        Log.e("MainActivity", "调用onpause");
    }
    
    @Override
    protected void onStop() {
        // TODO Auto-generated method stub
        super.onStop();
        Log.e("MainActivity", "调用onstop");
    }
    
    @Override
    protected void onDestroy() {
        // TODO Auto-generated method stub
        super.onDestroy();
        Log.e("MainActivity", "调用ondestroy");
    }
    
    @Override
    protected void onRestart() {
        // TODO Auto-generated method stub
        super.onRestart();
        Log.e("MainActivity", "调用onRestart");
    }
    
    //使用显式意图开启界面2（一般同一个应用程序 用显式意图）
    public void click1(View view){
        Intent intent=new Intent(this,SecondActivity.class);
        startActivity(intent);
        
    }
    
    //使用隐式意图开启界面2（不同应用程序，用隐式意图，例如开启浏览器、手机照相机等）
    public void click2(View view){
        Intent intent=new Intent();
        intent.setAction("com.gd.activity2");
        intent.addCategory("android.intent.category.DEFAULT");
        startActivity(intent);
    }
    
    public void click3(View view){
        Intent intent=new Intent();
        intent.setAction("android.intent.action.VIEW");
        intent.setData(Uri.parse("http://www.baidu.com"));
        startActivity(intent);
        
    }
    public void click4(View view){
        Intent intent=new Intent();
        intent.setAction("android.intent.action.VIEW");
        intent.setData(Uri.parse("tel:123456"));
        startActivity(intent);
        
    }
    
    public void click5(View view){
        Intent intent=new Intent();
        intent.setAction("android.media.action.IMAGE_CAPTURE");
        intent.addCategory("android.intent.category.DEFAULT");
        startActivity(intent);
        
    }


    
}

package com.example.lj;

import android.app.Activity;
import android.os.Bundle;

public class SecondActivity extends Activity {
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_second);
    }

}

<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=".Activity2" >
    <Button 
        android:id="@+id/bt2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="开启界面三"
        />
    
    
    
    
    
    
    
</RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.app6"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="17" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.example.app6.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="com.example.app6.Activity2"
            android:label="@string/title_activity_activity2" >
        </activity>
        <activity
            android:name="com.example.app6.Activity3"
            android:label="@string/title_activity_activity3" >
            
              <intent-filter>
                <action android:name="com.lrp.start" />

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

</manifest>  

 

 

 

 

 

 

3.2个edittext,4个按钮一个textview，实现简单计算器。

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity"
    android:orientation="vertical">
    <TextView
        android:id="@+id/tv1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="计算器"
        android:textSize="36dp"
        android:layout_margin="30dp"
        />
    <EditText
        android:id="@+id/et1"
        android:layout_width="360dp"
        android:layout_height="60dp"/>
    <EditText
        android:id="@+id/et2"
        android:layout_width="360dp"
        android:layout_height="60dp"/>


    <Button
        android:id="@+id/btn_1"
        android:layout_width="70dp"
        android:layout_height="70dp"
        android:text="+"
        android:textSize="50dp"/>
    <Button
        android:id="@+id/btn_2"
    android:layout_width="70dp"
    android:layout_height="70dp"
    android:text="-"
    android:textSize="50dp"/>
    <Button
        android:id="@+id/btn_3"
    android:layout_width="70dp"
    android:layout_height="70dp"
    android:text="*"
    android:textSize="60dp"/>
    <Button
        android:id="@+id/btn_4"
    android:layout_width="70dp"
    android:layout_height="70dp"
    android:text="/"
    android:textSize="60dp"/>
    <TextView
        android:id="@+id/tv2"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:text="结果是"
        android:textSize="36dp"
        android:layout_margin="26dp"/>
</LinearLayout>

package com.example.jisuan;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate( savedInstanceState );
        setContentView( R.layout.activity_main);
        findViewById( R.id.btn_1 ).setOnClickListener( new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById( R.id.et1 ))).getText().toString();
                String num2=((EditText)(findViewById( R.id.et2 ))).getText().toString();
                int n1= Integer.parseInt( num1 );
                int n2=Integer.parseInt( num2 );
                int sum=n1+n2;
                TextView tv1=findViewById( R.id.tv2 );
                tv1.setText( "结果是"+sum );
            }
        } );
        findViewById( R.id.btn_2 ).setOnClickListener( new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById( R.id.et1 ))).getText().toString();
                String num2=((EditText)(findViewById( R.id.et2 ))).getText().toString();
                int n1=Integer.parseInt( num1 );
                int n2=Integer.parseInt( num2 );
                int sum=n1-n2;
                TextView tv1=findViewById( R.id.tv2 );
                tv1.setText("结果是"+sum);
            }
        } );
        findViewById( R.id.btn_3 ).setOnClickListener( new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById( R.id.et1 ))).getText().toString();
                String num2=((EditText)(findViewById( R.id.et2 ))).getText().toString();
                int n1=Integer.parseInt( num1 );
                int n2=Integer.parseInt( num2 );
                int sum=n1*n2;
                TextView tv1=findViewById( R.id.tv2 );
                tv1.setText("结果是"+sum);
            }
        } );


        findViewById( R.id.btn_4).setOnClickListener( new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String num1=((EditText)(findViewById( R.id.et1 ))).getText().toString();
                String num2=((EditText)(findViewById( R.id.et2 ))).getText().toString();
                int n1=Integer.parseInt( num1 );
                int n2=Integer.parseInt( num2 );
                int sum=n1/n2;
                TextView tv1=findViewById( R.id.tv2 );
                tv1.setText("结果是"+sum);
            }
        } );
    }
}