SnapdragonCamera: fix screen flash on resuming

Currently preview cover will be hidden shortly after preview started,
but if the actual first frame comes late, the main screen will flash.
Register a oneshot preview callback to hide preview cover.
Register the callback before calling startPreview.

Change-Id: Ia9910c4302a598bd1faef87eb630c5c838e12d3b
CRs-Fixed: 909772

1 files changed, 8 insertions, 2 deletions

diff --git a/src/com/android/camera/PhotoModule.java b/src/com/android/camera/PhotoModule.java
index 97eef5ed1..77d613940 100644
--- a/src/com/android/camera/PhotoModule.java
+++ b/src/com/android/camera/PhotoModule.java
@@ -533,7 +533,6 @@ public class PhotoModule
         if (mCameraState == SNAPSHOT_IN_PROGRESS) {
             return;
         }
-        mUI.hidePreviewCover();
         setCameraState(IDLE);
         mFocusManager.onPreviewStarted();
         startFaceDetection();
@@ -2707,8 +2706,15 @@ public class PhotoModule
         }
 
         setCameraParameters(UPDATE_PARAM_ALL);
-
+        mCameraDevice.setOneShotPreviewCallback(mHandler,
+                new CameraManager.CameraPreviewDataCallback() {
+                    @Override
+                    public void onPreviewFrame(byte[] data, CameraProxy camera) {
+                        mUI.hidePreviewCover();
+                    }
+                });
         mCameraDevice.startPreview();
+
         mHandler.sendEmptyMessage(ON_PREVIEW_STARTED);
 
         setDisplayOrientation();