Question

我想创建一个应用程序，其中一些信息对用户可见在锁定屏幕上。我在互联网上搜索过。我发现，出于安全原因，android不允许锁定屏幕顶部的活动布局。正如有人建议我尝试使用服务和WindowManger。以下是我上网的代码。

public class MyService extends Service {

WindowManager mWindowManager;
View mView;

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

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    registerOverlayReceiver();
    return super.onStartCommand(intent, flags, startId);
}

private void showDialog(){
    WindowManager mWindowManager = (WindowManager) getSystemService(WINDOW_SERVICE);

    View mView = View.inflate(getApplicationContext(),R.layout.activity_main, null);

    WindowManager.LayoutParams mLayoutParams = new WindowManager.LayoutParams(
            ViewGroup.LayoutParams.WRAP_CONTENT,
            ViewGroup.LayoutParams.WRAP_CONTENT, 0, 0,
            WindowManager.LayoutParams.TYPE_SYSTEM_OVERLAY,
            WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED
                    | WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD
                    | WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON,
            PixelFormat.RGBA_8888);
    mView.setVisibility(View.VISIBLE);
    mWindowManager.addView(mView, mLayoutParams);

}

private void hideDialog(){
    if(mView != null && mWindowManager != null){
        mWindowManager.removeView(mView);
        mView = null;
    }
}

@Override
public void onDestroy() {
    unregisterOverlayReceiver();
    super.onDestroy();
}

private void registerOverlayReceiver() {
    IntentFilter filter = new IntentFilter();
    filter.addAction(Intent.ACTION_SCREEN_ON);
    filter.addAction(Intent.ACTION_SCREEN_OFF);
    filter.addAction(Intent.ACTION_USER_PRESENT);
    registerReceiver(overlayReceiver, filter);
}

private void unregisterOverlayReceiver() {
    hideDialog();
    unregisterReceiver(overlayReceiver);
}


private BroadcastReceiver overlayReceiver = new BroadcastReceiver() {
    @Override
    public void onReceive(Context context, Intent intent) {
        String action = intent.getAction();
        if (action.equals(Intent.ACTION_SCREEN_ON)) {
            showDialog();
        }
        else if (action.equals(Intent.ACTION_USER_PRESENT)) {
            hideDialog();
        }
        else if (action.equals(Intent.ACTION_SCREEN_OFF)) {
            hideDialog();
        }
    }
};

}

我理解这段代码。但是当我尝试这段代码时。这不起作用。我许可了

<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW"></uses-permission>

任何人都可以帮我解决这个问题吗？

如何在锁屏Android顶部显示一些布局

0 个答案: