Use mutable drawable to avoid sharing drawable states

Bug: 12594617
Change-Id: I798b67ed42a5593c346643d42ebf1143d54551e6

2 files changed, 23 insertions, 4 deletions

diff --git a/src/com/android/camera/ui/BottomBar.java b/src/com/android/camera/ui/BottomBar.java
index 3ee8b73b1..35b514231 100644
--- a/src/com/android/camera/ui/BottomBar.java
+++ b/src/com/android/camera/ui/BottomBar.java
@@ -511,10 +511,19 @@ public class BottomBar extends FrameLayout
     }
 
     /**
-     * Set the shutter button's icon resource
+     * Sets the shutter button's icon resource. By default, all drawables instances
+     * loaded from the same resource share a common state; if you modify the state
+     * of one instance, all the other instances will receive the same modification.
+     * In order to modify properties of this icon drawable without affecting other
+     * drawables, here we use a mutable drawable which is guaranteed to not share
+     * states with other drawables.
      */
     public void setShutterButtonIcon(int resId) {
-        mShutterButton.setImageResource(resId);
+        Drawable iconDrawable = getResources().getDrawable(resId);
+        if (iconDrawable != null) {
+            iconDrawable = iconDrawable.mutate();
+        }
+        mShutterButton.setImageDrawable(iconDrawable);
     }
 
     /**
diff --git a/src/com/android/camera/ui/ModeSelectorItem.java b/src/com/android/camera/ui/ModeSelectorItem.java
index bf89f2b09..44c567cbd 100644
--- a/src/com/android/camera/ui/ModeSelectorItem.java
+++ b/src/com/android/camera/ui/ModeSelectorItem.java
@@ -20,6 +20,7 @@ import android.content.Context;
 import android.graphics.Bitmap;
 import android.graphics.Canvas;
 import android.graphics.Typeface;
+import android.graphics.drawable.Drawable;
 import android.graphics.drawable.GradientDrawable;
 import android.util.AttributeSet;
 import android.widget.FrameLayout;
@@ -147,12 +148,21 @@ class ModeSelectorItem extends FrameLayout {
     }
 
     /**
-     * Sets image resource as the icon for the mode.
+     * Sets image resource as the icon for the mode. By default, all drawables instances
+     * loaded from the same resource share a common state; if you modify the state
+     * of one instance, all the other instances will receive the same modification.
+     * In order to modify properties of this icon drawable without affecting other
+     * drawables, here we use a mutable drawable which is guaranteed to not share
+     * states with other drawables.
      *
      * @param resource resource id of the asset to be used as icon
      */
     public void setImageResource(int resource) {
-        mIcon.setImageResource(resource);
+        Drawable drawableIcon = getResources().getDrawable(resource);
+        if (drawableIcon != null) {
+            drawableIcon = drawableIcon.mutate();
+        }
+        mIcon.setImageDrawable(drawableIcon);
     }
 
     /**