Android学习总结——Broadcast
Posted ChaoYoung
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一.利用BroadcastReceiever监听短信
androidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.boradcast">
<uses-permission android:name="android.permission.RECEIVE_SMS"/>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity"
android:screenOrientation="landscape"
android:theme="@android:style/Theme.NoTitleBar.Fullscreen">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<receiver android:name=".MyBoradcast">
<intent-filter>
<action android:name ="android.provider.Telephony.SMS_RECEIVED"></action>
</intent-filter>
</receiver>
</application>
</manifest>
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<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.example.boradcast.MainActivity">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello World!" />
</RelativeLayout>
MainActivity:
package com.example.boradcast;
import android.app.Activity;
import android.os.Bundle;
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
}
MyBoradcast:
package com.example.boradcast;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.widget.Toast;
/**
* Created by 杨雄超 on 2016/8/17.
*/
public class MyBoradcast extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
Toast.makeText(context,"你有新信息",Toast.LENGTH_SHORT).show();
}
}
总结:android:theme="@android:style/Theme.NoTitleBar.Fullscreen"> 去除状态栏和标题栏
<action android:name ="android.provider.Telephony.SMS_RECEIVED"></action> 广播接受者关注的是什么事件
android:screenOrientation="landscape" 横屏
二.自定义广播的发送和接收
发送:
activity_main.xml:
<?xml version="1.0" encoding="utf-8"?>
<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="com.example.broadcastsender.MainActivity">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/btn_StartBroadcast"
android:text="发送广播"/>
</RelativeLayout>
MainActivity:
package com.example.broadcastsender;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
private Button btnStartBroad;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnStartBroad=(Button) findViewById(R.id.btn_StartBroadcast);
btnStartBroad.setOnClickListener(this);
}
@Override
public void onClick(View view) {
switch (view.getId()){
case R.id.btn_StartBroadcast:
Intent intent=new Intent();
//设置action,便于接收方使用
intent.setAction("com.xch");
intent.putExtra("key","发送广播了!");
//发送广播
sendBroadcast(intent);
break;
}
}
}
接收:
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.broadcastreceive">
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<receiver android:name=".MyBroadcast">
<intent-filter>
<!--此处action为发送方设置的action-->
<action android:name="com.xch"/>
</intent-filter>
</receiver>
</application>
</manifest>
MyBroadcast:
package com.example.broadcastreceive; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.widget.Toast; /** * Created by 杨雄超 on 2016/8/31. */ public class MyBroadcast extends BroadcastReceiver{ @Override public void onReceive(Context context, Intent intent) { String str=intent.getExtras().getString("key"); Toast.makeText(context,str,Toast.LENGTH_SHORT).show(); } }
总结:自定义广播发送和接收可以利用Intent,需要注意的是要设置一个action,便于接收:如下
intent.setAction("com.xch");
<action android:name="com.xch"/>
结果:
三: 广播接收者的优先级别
1.在AndroidManifest.xml中设置优先级别,具体为在intent-filter标签中设置android:priority="1000";这里设置1000,如果我们要让这个接受者为最高级别,则其他接收者级别应该设置得比这个低。
2.在代码中发送方应该发送有序的广播,之前的sendBroadcast(intent);是无序的,这里我们应该用:sendOrderedBroadcast(intent,null);
3.在接收方拦截掉比当前优先级别低的广播:abortBroadcast();
具体代码如下:
发送广播:
package com.example.broadcastsender;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
private Button btnStartBroad;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnStartBroad=(Button) findViewById(R.id.btn_StartBroadcast);
btnStartBroad.setOnClickListener(this);
}
@Override
public void onClick(View view) {
switch (view.getId()){
case R.id.btn_StartBroadcast:
Intent intent=new Intent();
//设置action,便于接收方使用
intent.setAction("com.xch");
intent.putExtra("key","发送广播了!");
//发送无序的广播
//sendBroadcast(intent);
//发送有序的广播
sendOrderedBroadcast(intent,null);
break;
}
}
}
接收广播:
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.broadcastreceive">
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<receiver android:name=".MyBroadcast">
<!--设置广播优先级:intent-filter标签下的android:priority=""-->
<intent-filter android:priority="1000">
<action android:name="com.xch"/>
</intent-filter>
</receiver>
</application>
</manifest>
MyBroadcast:
package com.example.broadcastreceive;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.widget.Toast;
/**
* Created by 杨雄超 on 2016/8/31.
*/
public class MyBroadcast extends BroadcastReceiver{
@Override
public void onReceive(Context context, Intent intent) {
String str=intent.getExtras().getString("key");
Toast.makeText(context,str,Toast.LENGTH_SHORT).show();
//拦截掉比当前优先级别低的广播
abortBroadcast();
}
}
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