Background color of TileDrawable must be opaque.

Change-Id: I6ac7b4ba6f68181424064377464e1896c2129f13

2 files changed, 9 insertions, 13 deletions

diff --git a/src/com/android/bitmap/drawable/ExtendedBitmapDrawable.java b/src/com/android/bitmap/drawable/ExtendedBitmapDrawable.java
index ac332a9..2e3d43f 100644
--- a/src/com/android/bitmap/drawable/ExtendedBitmapDrawable.java
+++ b/src/com/android/bitmap/drawable/ExtendedBitmapDrawable.java
@@ -22,6 +22,7 @@ import android.animation.ValueAnimator;
 import android.animation.ValueAnimator.AnimatorUpdateListener;
 import android.content.res.Resources;
 import android.graphics.Canvas;
+import android.graphics.Color;
 import android.graphics.ColorFilter;
 import android.graphics.Rect;
 import android.graphics.drawable.Drawable;
@@ -634,7 +635,7 @@ public class ExtendedBitmapDrawable extends BasicBitmapDrawable implements
         public float parallaxSpeedMultiplier = 1;
 
         /**
-         * Optional field if {@link #FEATURE_STATE_CHANGES} is supported.
+         * Optional field if {@link #FEATURE_STATE_CHANGES} is supported. Must be an opaque color.
          *
          * See {@link android.graphics.Color}.
          */
@@ -706,6 +707,11 @@ public class ExtendedBitmapDrawable extends BasicBitmapDrawable implements
                             "ExtendedOptions: To support FEATURE_STATE_CHANGES, "
                                     + "placeholderAnimationDuration must be set correctly.");
                 }
+                if (backgroundColor != 0 && Color.alpha(backgroundColor) != 255) {
+                    throw new IllegalStateException(
+                            "ExtendedOptions: To support FEATURE_STATE_CHANGES, "
+                                    + "backgroundColor must be set to an opaque color.");
+                }
             }
         }
     }
diff --git a/src/com/android/bitmap/drawable/TileDrawable.java b/src/com/android/bitmap/drawable/TileDrawable.java
index 485e7ca..42400b4 100644
--- a/src/com/android/bitmap/drawable/TileDrawable.java
+++ b/src/com/android/bitmap/drawable/TileDrawable.java
@@ -19,7 +19,6 @@ package com.android.bitmap.drawable;
 import android.animation.ValueAnimator;
 import android.animation.ValueAnimator.AnimatorUpdateListener;
 import android.graphics.Canvas;
-import android.graphics.Color;
 import android.graphics.ColorFilter;
 import android.graphics.Paint;
 import android.graphics.Rect;
@@ -91,13 +90,10 @@ public class TileDrawable extends Drawable implements Drawable.Callback {
         if (!isVisible() && mPaint.getAlpha() == 0) {
             return;
         }
-        // Save paint alpha.
         final int alpha = mPaint.getAlpha();
-        mPaint.setColor(getColorWithAlpha(mOpts.backgroundColor, alpha));
-        canvas.drawRect(getBounds(), mPaint);
-        // Restore paint alpha.
+        mPaint.setColor(mOpts.backgroundColor);
         mPaint.setAlpha(alpha);
-
+        canvas.drawRect(getBounds(), mPaint);
         if (mInner != null) mInner.draw(canvas);
     }
 
@@ -180,10 +176,4 @@ public class TileDrawable extends Drawable implements Drawable.Callback {
     public void unscheduleDrawable(Drawable who, Runnable what) {
         unscheduleSelf(what);
     }
-
-    private static int getColorWithAlpha(int color, int alpha) {
-        float fade = alpha / 255f;
-        return Color.argb((int) (fade * Color.alpha(color)), Color.red(color), Color.green(color),
-                Color.blue(color));
-    }
 }