Android的本地广播

悠悠 2024-04-01 13:28 28阅读 0赞

本地广播和全局广播(按照传播范围)  
本地广播(**app内部传播**)数据,其它app收不到,**保证了数据的安全性**  
全局广播,可以在整个手机所有App之间传播通信,会有安全性问题。普通广播默认就是全局广播。  
例如监听开机充电打电话发短信修改时间这些

**1.本地广播只能通过动态注册**  
**2.本地广播需要用LoaalBroadcasrManager**  
代码示例:  
xml文件:

<?xml version="1.0" encoding="utf-8"?>
    <androidx.constraintlayout.widget.ConstraintLayout 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=".broadcast.local.LocalBroadCastActivity">
    
        <Button
            android:id="@+id/btn_local"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="20dp"
            android:onClick="sendLocalBroadcast"
            android:text="本地广播">
    
        </Button>
    </androidx.constraintlayout.widget.ConstraintLayout>

java代码:  
本地广播类:MyLocalBroadcastReceiver

public class MyLocalBroadcastReceiver extends BroadcastReceiver {
        private static final String TAG = "MyLocalBroadcastReceiver";
    
        @Override
        public void onReceive(Context context, Intent intent) {
    
            Log.d(TAG, "onReceive: 收到了本地广播");
        }
    }

Activity类:LocalBroadCastActivity

public class LocalBroadCastActivity extends AppCompatActivity {
    
        private MyLocalBroadcastReceiver myLocalBroadcastReceiver = new MyLocalBroadcastReceiver();
        LocalBroadcastManager mLocalBroadcastManager;
    
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_local_broad_cast);
    
            /**
             * 本地广播只能动态注册
             */
            //实例化
            mLocalBroadcastManager = LocalBroadcastManager.getInstance(this);
            //注册广播接收器
            IntentFilter intentFilter = new IntentFilter();
            intentFilter.addAction("local_broad_cast");
            mLocalBroadcastManager.registerReceiver(myLocalBroadcastReceiver, intentFilter);
        }
    
        //发送本地广播
        public void sendLocalBroadcast(View view) {
            Intent intent = new Intent();
            intent.setAction("local_broad_cast");
            mLocalBroadcastManager.sendBroadcast(intent);
        }
    
        //解除注册
        @Override
        protected void onDestroy() {
            super.onDestroy();
            mLocalBroadcastManager.unregisterReceiver(myLocalBroadcastReceiver);
        }
    }