Android：如何通过锁定屏幕显示对话框或活动[未解锁屏幕]

Question

我有一个应用程序，它将从服务器接收消息并向用户发出一个对话框。所以当手机在锁定屏幕上时我希望对话框显示在锁定屏幕的顶部但不解锁它。是否有人给我建议？

Answer 1

I solved something similar in the following way. Create services, to broadcast the action " ACTION_SCREEN_ON & ACTION_USER_PRESENT & ACTION_SCREEN_OFF ", create function to show the windows with WINDOW_SERVICE . I use a service for my requirements, but it can adapt.

public class OverlayService extends Service {

    private static final String TAG = OverlayService.class.getSimpleName();
    WindowManager mWindowManager;
    View mView;
    Animation mAnimation;

    @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(String aTitle){
        mWindowManager = (WindowManager) getSystemService(WINDOW_SERVICE);

        mView = View.inflate(getApplicationContext(), R.layout.fragment_overlay, null);
        mView.setTag(TAG);

        int top = getApplicationContext().getResources().getDisplayMetrics().heightPixels / 2;

        RelativeLayout dialog = (RelativeLayout) mView.findViewById(R.id.dialog);
        LayoutParams lp = (LayoutParams) dialog.getLayoutParams();
        lp.topMargin = top;
        lp.bottomMargin = top;
        mView.setLayoutParams(lp);

        ImageButton imageButton = (ImageButton) mView.findViewById(R.id.close);
        lp = (LayoutParams) imageButton.getLayoutParams();
        lp.topMargin = top - 58;
        imageButton.setLayoutParams(lp);
        imageButton.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                mView.setVisibility(View.INVISIBLE);
            }
        });

        TextView title = (TextView) mView.findViewById(R.id.Title);
        title.setText(aTitle);

        final WindowManager.LayoutParams mLayoutParams = new WindowManager.LayoutParams(
        ViewGroup.LayoutParams.MATCH_PARENT,
        ViewGroup.LayoutParams.MATCH_PARENT, 0, 0,
        WindowManager.LayoutParams.TYPE_SYSTEM_ERROR,
        WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED
                | WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD
                | WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON
                | WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON ,
        PixelFormat.RGBA_8888);

        mView.setVisibility(View.VISIBLE);
        mAnimation = AnimationUtils.loadAnimation(getApplicationContext(), R.anim.in);
        mView.startAnimation(mAnimation);
        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();
            Log.d(TAG, "[onReceive]" + action);
            if (action.equals(Intent.ACTION_SCREEN_ON)) {
                showDialog("Esto es una prueba y se levanto desde");
            }
            else if (action.equals(Intent.ACTION_USER_PRESENT)) {
                hideDialog();
            }
            else if (action.equals(Intent.ACTION_SCREEN_OFF)) {
                hideDialog();
            }
        }
    };
}

I hope it useful!

Answer 2

public void onAttachedToWindow() {
      Window window = getWindow();
      window.addFlags(WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON
           | WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED
           | WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON
           | WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD);
}

Answer 3

Finally I achieved the same. Don't go for activity, because android will not show lock screen behind your activity for security reason, so use service instead of Activity.

Below is my code in onStartCommand of my service

WindowManager mWindowManager = (WindowManager) getSystemService(WINDOW_SERVICE);

View mView = mInflater.inflate(R.layout.score, 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
/* | WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON */,
PixelFormat.RGBA_8888);

mWindowManager.addView(mView, mLayoutParams);

And add <uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" /> to manifest