常規(guī)情況下茄菊，activity與service之間的通訊都是通過intent進行數(shù)據(jù)傳遞的

本文講述通過LocalBroadcastManager實現(xiàn)其通訊舶胀。

LocalBroadcastManager 是 Android 提供的用于在應(yīng)用內(nèi)部發(fā)送廣播的工具，它可以有效地在 Activity 和 Service 之間進行通信网梢。使用 LocalBroadcastManager 可以高效地在同一個應(yīng)用內(nèi)的不同組件之間通信震缭，且相比于系統(tǒng)廣播，它的性能開銷更小战虏，并且不會被其他應(yīng)用接收到拣宰。

step 1 添加依賴庫

implementation 'androidx.localbroadcastmanager:localbroadcastmanager:1.0.0'

step 2 創(chuàng)建一個activity 接收廣播

import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;
import android.content.IntentFilter;
import android.os.Bundle;
import android.widget.Toast;
import androidx.appcompat.app.AppCompatActivity;
import androidx.localbroadcastmanager.content.LocalBroadcastManager;

public class MyActivity extends AppCompatActivity {

    private BroadcastReceiver mReceiver = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            // 處理接收到的廣播
            String data = intent.getStringExtra("extra_data");
            Toast.makeText(context, data, Toast.LENGTH_SHORT).show();
        }
    };

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

        // 啟動 Service
        Intent serviceIntent = new Intent(this, MyService.class);
        startService(serviceIntent);
    }

    @Override
    protected void onStart() {
        super.onStart();
        // 注冊廣播接收器
        LocalBroadcastManager.getInstance(this).registerReceiver(mReceiver,
                new IntentFilter("MY_ACTION"));
    }

    @Override
    protected void onStop() {
        super.onStop();
        // 注銷廣播接收器
        LocalBroadcastManager.getInstance(this).unregisterReceiver(mReceiver);
    }
}

step 3 創(chuàng)建一個service發(fā)送廣播

import android.app.Service;
import android.content.Intent;
import android.os.IBinder;
import androidx.localbroadcastmanager.content.LocalBroadcastManager;

public class MyService extends Service {

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        // 發(fā)送廣播
        Intent localIntent = new Intent("MY_ACTION");
        localIntent.putExtra("extra_data", "Hello from Service");
        LocalBroadcastManager.getInstance(this).sendBroadcast(localIntent);
        return START_NOT_STICKY;
    }

    @Override
    public IBinder onBind(Intent intent) {
        return null;
    }
}