Fix LongScreenshotActivity rotation

- Always set image preview alpha.
- Don't set the enter transition position if the screenshot isn't
loaded.

Bug: 191179430
Test: Rotate LongScreenshotActivity, observe no crashes and images show
      up.
Change-Id: I1d8b84d6a23c7b9e5a011b48834d53bbb67819fd

1 files changed, 17 insertions, 14 deletions

diff --git a/packages/SystemUI/src/com/android/systemui/screenshot/LongScreenshotActivity.java b/packages/SystemUI/src/com/android/systemui/screenshot/LongScreenshotActivity.java
index d5b4032b1c0f..2a427f767158 100644
--- a/packages/SystemUI/src/com/android/systemui/screenshot/LongScreenshotActivity.java
+++ b/packages/SystemUI/src/com/android/systemui/screenshot/LongScreenshotActivity.java
@@ -250,6 +250,7 @@ public class LongScreenshotActivity extends Activity {
         Log.d(TAG, "onCachedImageLoaded(imageResult=" + imageResult + ")");
         BitmapDrawable drawable = new BitmapDrawable(getResources(), imageResult.bitmap);
         mPreview.setImageDrawable(drawable);
+        mPreview.setAlpha(1f);
         mMagnifierView.setDrawable(drawable, imageResult.bitmap.getWidth(),
                 imageResult.bitmap.getHeight());
         mCropView.setVisibility(View.VISIBLE);
@@ -476,19 +477,21 @@ public class LongScreenshotActivity extends Activity {
         params.height = boundaries.height();
         mTransitionView.setLayoutParams(params);
 
-        ConstraintLayout.LayoutParams enterTransitionParams =
-                (ConstraintLayout.LayoutParams) mEnterTransitionView.getLayoutParams();
-        float topFraction = Math.max(0,
-                -mLongScreenshot.getTop() / (float) mLongScreenshot.getHeight());
-        enterTransitionParams.width = (int) (scale * drawable.getIntrinsicWidth());
-        enterTransitionParams.height = (int) (scale * mLongScreenshot.getPageHeight());
-        mEnterTransitionView.setLayoutParams(enterTransitionParams);
-
-        Matrix matrix = new Matrix();
-        matrix.setScale(scale, scale);
-        matrix.postTranslate(0, -scale * drawable.getIntrinsicHeight() * topFraction);
-        mEnterTransitionView.setImageMatrix(matrix);
-        mEnterTransitionView.setTranslationY(
-                topFraction * previewHeight + mPreview.getPaddingTop() + extraPadding);
+        if (mLongScreenshot != null) {
+            ConstraintLayout.LayoutParams enterTransitionParams =
+                    (ConstraintLayout.LayoutParams) mEnterTransitionView.getLayoutParams();
+            float topFraction = Math.max(0,
+                    -mLongScreenshot.getTop() / (float) mLongScreenshot.getHeight());
+            enterTransitionParams.width = (int) (scale * drawable.getIntrinsicWidth());
+            enterTransitionParams.height = (int) (scale * mLongScreenshot.getPageHeight());
+            mEnterTransitionView.setLayoutParams(enterTransitionParams);
+
+            Matrix matrix = new Matrix();
+            matrix.setScale(scale, scale);
+            matrix.postTranslate(0, -scale * drawable.getIntrinsicHeight() * topFraction);
+            mEnterTransitionView.setImageMatrix(matrix);
+            mEnterTransitionView.setTranslationY(
+                    topFraction * previewHeight + mPreview.getPaddingTop() + extraPadding);
+        }
     }
 }