public class MainActivity extends AppCompatActivity {
private IntentFilter intentFilter = new IntentFilter();;
private NetworkChangeReceiver networkChangeReceiver = new NetworkChangeReceiver();
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
intentFilter.addAction("android.net.conn.CONNECTIVITY_CHANGE");
registerReceiver(networkChangeReceiver,intentFilter);
}
@Override
protected void onDestroy() {
super.onDestroy();
//一定要取消
unregisterReceiver(networkChangeReceiver);
}
class NetworkChangeReceiver extends BroadcastReceiver {
@Override
public void onReceive(Context context, Intent intent) {
Toast.makeText(context,"123",Toast.LENGTH_SHORT).show();
}
}
}