commit 3e024c0e1c52a72eea7a9668667ce59d81a827e3
author Mehdi Alizadeh <mett@google.com> Mon Apr 30 11:15:39 2018 -0700
committer Mehdi Alizadeh <mett@google.com> Mon Apr 30 16:05:25 2018 -0700
tree 2193f635eb626a5bc92d81b15737400ac61e47bd
parent 3aa3eb51e2403a5f18ba1b16c574127405252a07

Fixes the incorrect hover icon color in drop bar when dark theme

Bug: 78641863
Test: Manual test with dark and light wallpapers
Change-Id: Ic3fb68f5c5f746482a7f23b11284e30ac3e10168

src/com/android/launcher3/ButtonDropTarget.java

diff --git a/src/com/android/launcher3/ButtonDropTarget.java b/src/com/android/launcher3/ButtonDropTarget.java
index c866880..c35ab97 100644
--- a/src/com/android/launcher3/ButtonDropTarget.java
+++ b/src/com/android/launcher3/ButtonDropTarget.java
@@ -192,8 +192,10 @@
             mCurrentFilter = new ColorMatrix();
         }
 
-        Themes.setColorScaleOnMatrix(getTextColor(), mSrcFilter);
-        Themes.setColorScaleOnMatrix(targetColor, mDstFilter);
+        int defaultTextColor = mOriginalTextColor.getDefaultColor();
+        Themes.setColorChangeOnMatrix(defaultTextColor, getTextColor(), mSrcFilter);
+        Themes.setColorChangeOnMatrix(defaultTextColor, targetColor, mDstFilter);
+
         ValueAnimator anim1 = ValueAnimator.ofObject(
                 new FloatArrayEvaluator(mCurrentFilter.getArray()),
                 mSrcFilter.getArray(), mDstFilter.getArray());

src/com/android/launcher3/util/Themes.java

diff --git a/src/com/android/launcher3/util/Themes.java b/src/com/android/launcher3/util/Themes.java
index 89597b9..d225093 100644
--- a/src/com/android/launcher3/util/Themes.java
+++ b/src/com/android/launcher3/util/Themes.java
@@ -78,4 +78,23 @@
         target.setScale(Color.red(color) / 255f, Color.green(color) / 255f,
                 Color.blue(color) / 255f, Color.alpha(color) / 255f);
     }
+
+    /**
+     * Changes a color matrix such that, when applied to srcColor, it produces dstColor.
+     *
+     * Note that values on the last column of target ColorMatrix can be negative, and may result in
+     * negative values when applied on a color. Such negative values will be automatically shifted
+     * up to 0 by the framework.
+     *
+     * @param srcColor The color to start from
+     * @param dstColor The color to create by applying target on srcColor
+     * @param target The ColorMatrix to transform the color
+     */
+    public static void setColorChangeOnMatrix(int srcColor, int dstColor, ColorMatrix target) {
+        target.reset();
+        target.getArray()[4] = Color.red(dstColor) - Color.red(srcColor);
+        target.getArray()[9] = Color.green(dstColor) - Color.green(srcColor);
+        target.getArray()[14] = Color.blue(dstColor) - Color.blue(srcColor);
+        target.getArray()[19] = Color.alpha(dstColor) - Color.alpha(srcColor);
+    }
 }