In my app I have a TextView and an ImageView that I update based on sensor information. This works perfectly on emulators and most of the handsets I have tried it on, however on Samsung handsets from the S7 to the S9 for some reason neither of them changes when they should be updated.
They are part of a Fragment overlaying a SurfaceView with a camera preview in it, there is a second SurfaceView overlay above them:
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="myApp.CameraViewFragment">
<FrameLayout
android:id="@+id/control"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentBottom="true"
android:layout_alignParentStart="true">
<myApp.CameraSurfaceView
android:id="@+id/camera_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true" />
<TextView
android:id="@+id/direction"
android:layout_width="80dp"
android:layout_height="wrap_content"
android:background="@color/black_overlay"
android:layout_gravity="center_horizontal"
android:gravity="center"
android:layout_centerInParent="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="10dp"
android:textSize="30dp"
android:text="" />
<ImageButton
android:id="@+id/gpsNotification"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/gps_unfixed"
android:layout_gravity="right"
android:tint="@color/gps_unfixed"
android:background="@null" />
</FrameLayout>
<com.myapp.OverlaySurfaceView
android:id="@+id/overlay_view"
android:layout_width="200dp"
android:layout_height="200dp"
android:gravity="center"
android:layout_gravity="center_horizontal|center_vertical"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true" />
</FrameLayout>
As far as I know, this is the relevant part of the Fragment code:
public class CameraViewFragment extends Fragment
{
private TextView directionView;
private CameraSurfaceView cameraView;
private OverlaySurfaceView overlay;
@Override
public void onViewCreated(final View view, Bundle savedInstanceState) {
cameraView = (CameraSurfaceView) view.findViewById(R.id.camera);
directionView = (TextView) view.findViewById(R.id.direction);
overlay = (OverlaySurfaceview) view.findViewById(R.id.overlay_view);
}
private void setDirection(AccurateDirection direction) {
final String directionString = direction.getDirection();
overlay.update();
Activity activity = getActivity();
if ( activity != null ) {
activity.runOnUiThread(new Runnable() {
public void run() {
directionView.setText(directionString);
directionView.invalidate();
}
});
}
}
}
When I run this on a regular handset, the directionView text updates as new direction data arrives. On a Samsung S7 the value gets set once, maybe updated once right at the start and then it seems to stick and not change any more. If I pause in the debugger and call directionView.getText() from the immediate window, it gives me the result I am expecting, not what I see on the screen. If I call directionView.setText('ABC') in the immediate window, the value returned by directionView.getText() changes but again the value on the screen does not. The ImageView also seems to get stuck in its initial state regardless of changes that should adjust it.
Previous questions on this topic seem to involve updates not being triggered from the UI thread or failures to call invalidate on the view component, so I have fixed both of those already but the problem persists.
I have only seen this on recent Samsung handsets ( my old Samsung S4 appears to be fine ) which makes it hard to troubleshoot. Why are my view components not changing on the Samsung devices and what do I need to do to get them to update?
Edit: Apologies to anyone previously attempting to answer this as I had ommited the OverlaySurfaceView and I now realise that the other components update correctly if the OverlaySurfaceView is removed, so apparently having that second SurfaceView in the view hierarchy is interfering, but only on Samsung. Switching on and off hardware acceleration doesn't seem to make a difference, but there may be a specific place or way that I need to do it. On a working handset hardware acceleration is marked as disabled for the `OverlaySurfaceView.
