Android学习之本地广播使用方法详解

时间:2022-07-28
本文章向大家介绍Android学习之本地广播使用方法详解,主要内容包括其使用实例、应用技巧、基本知识点总结和需要注意事项,具有一定的参考价值,需要的朋友可以参考一下。

本地广播信息只能在应用程序内部传递,同时广播接收器也只能接收应用程序内部的广播消息。

MainActivity代码

package com.example.luobo.mybroadcastreceiver;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.support.v4.content.LocalBroadcastManager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements View.OnClickListener{

  private Button button;
  private IntentFilter intentFilter;
  private LocalBroadcastManager localBroadcastManager ;
  private LocalReceiver localReciiver;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    button = (Button)findViewById(R.id.send_button);
    button.setOnClickListener(this);
    localBroadcastManager = LocalBroadcastManager.getInstance(this);//使用
    intentFilter = new IntentFilter();
    intentFilter.addAction("com.example.luobo.mybroadcastreceiver.LOCAL_BROADCAST");
    localReciiver = new LocalReceiver();
    localBroadcastManager.registerReceiver(localReciiver,intentFilter);
  }

  @Override
  protected void onDestroy() {
    super.onDestroy();
    localBroadcastManager.unregisterReceiver(localReciiver);
  }

  @Override
  public void onClick(View view) {
    Intent intent = new Intent("com.example.luobo.mybroadcastreceiver.LOCAL_BROADCAST");
    localBroadcastManager.sendBroadcast(intent);
  }
  class LocalReceiver extends BroadcastReceiver{
    @Override
    public void onReceive(Context context, Intent intent) {
      Toast.makeText(context,"received local broadcast",Toast.LENGTH_SHORT).show();
    }
  }
}

首先通过LocalBroadcastManager(本地广播管理类)的getInstance(this)方法获取实例,注册广播消息时是调用localBroadcastManager实例的registerReceiver(参数1,参数2)方法注册(参数1是本地广播接受者,参数2是过滤器只选择接收特定的广播消息),调用localBroadcastManager实例的sendBroadcast(Initent initent)方法发送广播消息。

MyRecevity

package com.example.luobo.mybroadcastreceiver;

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.widget.Toast;

public class MyReceiver extends BroadcastReceiver {

  @Override
  public void onReceive(Context context, Intent intent) {
    Toast.makeText(context,"Received in MyBroadCastReceiver",Toast.LENGTH_SHORT).show();
    abortBroadcast();
  }
}

activity_main.xml

<?xml version="1.0" encoding="utf-8"? 
<android.support.constraint.ConstraintLayout 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="com.example.luobo.mybroadcastreceiver.MainActivity" 
  <Button
    android:id="@+id/send_button"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="发送广播"/ 

</android.support.constraint.ConstraintLayout 

AndroidMainfest.aml

<?xml version="1.0" encoding="utf-8"? 
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
  package="com.example.luobo.mybroadcastreceiver" 

  <application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    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=".MyReceiver"
      android:enabled="true"
      android:exported="true" 
      <intent-filter
        android:priority="100" 
        <action android:name="com.example.luobo.mybroadcastreceiver.LOCAL_BROADCAST"/ 
      </intent-filter 
    </receiver 
  </application 

</manifest 

以上就是本文的全部内容,希望对大家的学习有所帮助。