Question

我有一个需要捕捉两个不同广播的Android活动。我目前的做法是在Activity中有一个BroadcastReceiver并用它捕捉广播：

public class MyActivity extends Activity {
    private MyActivity.BroadcastListener mBroadcastListener;
    private boolean mIsActivityPaused = false;

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

        // Create the broadcast listener and register the filters
        mIsActivityPaused = false;
        mBroadcastListener = new BroadcastListener();

        IntentFilter filter = new IntentFilter();
        filter.addAction(Params.INTENT_REFRESH);
        filter.addAction(Params.INTENT_UPDATE);
        registerReceiver(mBroadcastListener, filter);
    }

    @Override
    protected void onResume() {
        super.onResume();
        mIsActivityPaused = false;
    }

    @Override
    protected void onPause() {
        super.onPause();
        mIsActivityPaused = true;
    }

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

    private void refresh() {
        // refresh
    }

    private void update() {
        // update
    }

    private class BroadcastListener extends BroadcastReceiver {

        @Override
        public void onReceive(Context context, Intent intent) {
            if (intent.getAction().equals(Params.INTENT_REFRESH && !mIsActivityPaused)) {
                refresh();
            } else if (intent.getAction().equals(Params.INTENT_UPDATE)) {
                update();
            }
        }
    }
}

我想仅在屏幕上显示我的活动时执行refresh()，但我想在活动的整个生命周期内捕获INTENT_UPDATE并执行update()，无论是否活动是否可见。

我没有找到任何方法只注销我在onCreate中注册的两个过滤器中的一个，所以我使用一个标志来启用或禁用INTENT_REFRESH广播时要执行的操作被捕获，具体取决于活动的状态。

问题是：这是正确的方法吗？

或者，如果有两个单独的BroadcastReceivers会更好：

public class MyActivity extends Activity {
    private MyActivity.BroadcastListenerRefresh mBroadcastListenerRefresh;
    private MyActivity.BroadcastListenerUpdate mBroadcastListenerUpdate;
    private boolean mIsBroadcastListenerRefreshRegistered = false;

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

        // Create the broadcast listeners
        mBroadcastListenerRefresh = new BroadcastListenerRefresh();
        mBroadcastListenerUpdate = new BroadcastListenerUpdate();

        registerReceiver(mBroadcastListenerRefresh, new IntentFilter(Params.INTENT_REFRESH));
        registerReceiver(mBroadcastListenerUpdate, new IntentFilter(Params.INTENT_UPDATE));
    }

    @Override
    protected void onResume() {
        super.onResume();
        if (mBroadcastListenerRefresh != null && !mIsBroadcastListenerRefreshRegistered) {
            registerReceiver(mBroadcastListenerRefresh, new IntentFilter(Params.INTENT_REFRESH));
            mIsBroadcastListenerRefreshRegistered = true;
        }
    }

    @Override
    protected void onPause() {
        super.onPause();
        if (mBroadcastListenerRefresh != null && mIsBroadcastListenerRefreshRegistered) {
            unregisterReceiver(mBroadcastListenerRefresh);
            mIsBroadcastListenerRefreshRegistered = false;
        }
    }

    @Override
    protected void onDestroy() {
        unregisterReceiver(mBroadcastListenerRefresh);
        unregisterReceiver(mBroadcastListenerUpdate);
        super.onDestroy();
    }

    private void refresh() {
        // refresh
    }

    private void update() {
        // update
    }

    private class BroadcastListenerRefresh extends BroadcastReceiver {

        @Override
        public void onReceive(Context context, Intent intent) {
            if (intent.getAction().equals(Params.INTENT_REFRESH)) {
                refresh();
            }
        }
    }

    private class BroadcastListenerUpdate extends BroadcastReceiver {

        @Override
        public void onReceive(Context context, Intent intent) {
            if (intent.getAction().equals(Params.INTENT_UPDATE)) {
                update();
            }
        }
    }
}

哪一个有更好的表现？

Answer 1

相反，您可以提供两种不同的意图过滤器：

仅用于刷新

IntentFilter filterRefresh = new IntentFilter(Params.INTENT_REFRESH);

过滤刷新和更新

IntentFilter filterRefreshUpdate = new IntentFilter();
filterRefreshUpdate.addAction(Params.INTENT_REFRESH);
filterRefreshUpdate.addAction(Params.INTENT_UPDATE);

现在您可以通过注册和取消注册所需的过滤器来切换目标过滤器，但接收者的实现方式是相同的

Answer 2

对于每个动作，创建IntentFilter并注册它。

@Override
protected void onResume() {

    super.onResume();

    BroadcastListener receiver = new BroadcastListener();

    // Register the filter for listening broadcast.
    IntentFilter filterRefresh = new IntentFilter(Params.INTENT_REFRESH);
    IntentFilter filterUpdate = new IntentFilter(Params.INTENT_UPDATE);

    registerReceiver(receiver, filterRefresh);
    registerReceiver(receiver, filterUpdate);
} 



private class BroadcastListener extends BroadcastReceiver {
    public void onReceive(Context ctx, Intent intent) {

        if (intent.getAction().equals(Params.INTENT_UPDATE)) {
            update();
        } else if(intent.getAction().equals(Params.INTENT_REFRESH)) {
            refresh();
        }
    }

}

Answer 3

使用 KOTLIN，您可以内联：

  broadcastReceiver = NukeBroadcastReceiver()
        registerReceiver(broadcastReceiver, IntentFilter().apply {
            addAction(ACTION_DESTROY_EVERYTHING)
            addAction(ACTION_RESTART_WORLD)
        })

BroadcastReceiver有多个过滤器或多个BroadcastReceivers？

3 个答案:

使用 KOTLIN，您可以内联：