SnapdragonCamera: hide the preview surface during suspend

Occasionally, the previous preview frame is presented and
caused the screen flashing, when continuously triggering
suspend/resume.
To resolve the issue, hide the preview surface during
suspend and make it visible during resume. This helps
to clear the remaining preview frames in the buffer.

CRs-Fixed: 991416
Change-Id: I96fff0fdae6bd14263f33b1a9032604596cf49c1

2 files changed, 9 insertions, 0 deletions

diff --git a/src/com/android/camera/PhotoModule.java b/src/com/android/camera/PhotoModule.java
index d7f38a156..e10d33b93 100644
--- a/src/com/android/camera/PhotoModule.java
+++ b/src/com/android/camera/PhotoModule.java
@@ -2364,6 +2364,7 @@ public class PhotoModule
     @Override
     public void onResumeAfterSuper() {
         mLastPhotoTakenWithRefocus = false;
+        mUI.showSurfaceView();
         // Add delay on resume from lock screen only, in order to to speed up
         // the onResume --> onPause --> onResume cycle from lock screen.
         // Don't do always because letting go of thread can cause delay.
@@ -2491,6 +2492,7 @@ public class PhotoModule
     public void onPauseAfterSuper() {
         Log.v(TAG, "On pause.");
         mUI.showPreviewCover();
+        mUI.hideSurfaceView();
 
         try {
             if (mOpenCameraThread != null) {
diff --git a/src/com/android/camera/PhotoUI.java b/src/com/android/camera/PhotoUI.java
index 02d8f7183..06f5604ba 100644
--- a/src/com/android/camera/PhotoUI.java
+++ b/src/com/android/camera/PhotoUI.java
@@ -1181,6 +1181,13 @@ public class PhotoUI implements PieListener,
         return mSurfaceHolder;
     }
 
+    public void hideSurfaceView() {
+        mSurfaceView.setVisibility(View.INVISIBLE);
+    }
+
+    public void showSurfaceView() {
+        mSurfaceView.setVisibility(View.VISIBLE);
+    }
     // Countdown timer
 
     private void initializeCountDown() {