1 files changed, 147 insertions, 0 deletions
diff --git a/src/com/android/launcher2/DimmableAppWidgetHostView.java b/src/com/android/launcher2/DimmableAppWidgetHostView.java
new file mode 100644
index 000000000..7a1d4f9da
--- /dev/null
+++ b/src/com/android/launcher2/DimmableAppWidgetHostView.java
@@ -0,0 +1,147 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.launcher2;
+
+import com.android.launcher.R;
+
+import android.content.Context;
+import android.graphics.Bitmap;
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.Paint;
+import android.graphics.PorterDuff;
+import android.view.View;
+
+public class DimmableAppWidgetHostView extends LauncherAppWidgetHostView {
+    public DimmableAppWidgetHostView(Context context) {
+        super(context);
+        mPaint.setFilterBitmap(true);
+    }
+
+    private final Paint mPaint = new Paint();
+    private int mAlpha;
+    private int mDimmedAlpha;
+    private Bitmap mDimmedView;
+    private Canvas mDimmedViewCanvas;
+    private boolean isDimmedViewUpdatePass;
+
+    private static float cubic(float r) {
+        return (float) (Math.pow(r-1, 3) + 1);
+    }
+
+    /**
+     * Returns the interpolated holographic highlight alpha for the effect we want when scrolling
+     * pages.
+     */
+    public static float highlightAlphaInterpolator(float r) {
+        final float pivot = 0.3f;
+        if (r < pivot) {
+            return Math.max(0.5f, 0.65f*cubic(r/pivot));
+        } else {
+            return Math.min(1.0f, 0.65f*cubic(1 - (r-pivot)/(1-pivot)));
+        }
+    }
+
+    /**
+     * Returns the interpolated view alpha for the effect we want when scrolling pages.
+     */
+    public static float viewAlphaInterpolator(float r) {
+        final float pivot = 0.6f;
+        if (r < pivot) {
+            return r/pivot;
+        } else {
+            return 1.0f;
+        }
+    }
+
+    private void setChildAlpha(float alpha) {
+        if (getChildCount() > 0) {
+            final View child = getChildAt(0);
+            if (child.getAlpha() != alpha) {
+                getChildAt(0).setAlpha(alpha);
+            }
+        }
+    }
+
+    private void updateChildAlpha() {
+        // hacky, but sometimes widgets get their alpha set back to 1.0f, so we call
+        // this to force them back
+        setChildAlpha(getAlpha());
+    }
+
+    @Override
+    public boolean onSetAlpha(int alpha) {
+        super.onSetAlpha(alpha);
+        return true;
+    }
+
+    @Override
+    public void setAlpha(float alpha) {
+        final float viewAlpha = viewAlphaInterpolator(alpha);
+        final float dimmedAlpha = highlightAlphaInterpolator(alpha);
+        mAlpha = (int) (viewAlpha * 255);
+        mDimmedAlpha = (int) (dimmedAlpha * 255);
+        super.setAlpha(viewAlpha);
+        setChildAlpha(viewAlpha);
+    }
+
+    private void updateDimmedView() {
+        if (mDimmedView == null) {
+            mDimmedView = Bitmap.createBitmap(getMeasuredWidth(), getMeasuredHeight(),
+                    Bitmap.Config.ARGB_8888);
+            mDimmedViewCanvas = new Canvas(mDimmedView);
+        }
+        mDimmedViewCanvas.drawColor(0x00000000);
+        mDimmedViewCanvas.concat(getMatrix());
+        isDimmedViewUpdatePass = true;
+        draw(mDimmedViewCanvas);
+        // make the bitmap look "dimmed"
+        int dimmedColor = getContext().getResources().getColor(R.color.dimmed_view_color);
+        mDimmedViewCanvas.drawColor(dimmedColor, PorterDuff.Mode.SRC_IN);
+        isDimmedViewUpdatePass = false;
+    }
+
+    @Override
+    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
+        super.onLayout(changed, left, top, right, bottom);
+
+        if (mDimmedView == null && mDimmedAlpha > 0.0f) {
+            updateDimmedView();
+        }
+    }
+
+    @Override
+    public void dispatchDraw(Canvas canvas) {
+        if (isDimmedViewUpdatePass) {
+            final float alpha = getAlpha();
+            canvas.save();
+            setAlpha(1.0f);
+            super.dispatchDraw(canvas);
+            canvas.restore();
+            setAlpha(alpha);
+        } else {
+            if (mDimmedView != null && mDimmedAlpha > 0) {
+                // draw the dimmed version of this widget
+                mPaint.setAlpha(mDimmedAlpha);
+                canvas.drawBitmap(mDimmedView, 0, 0, mPaint);
+            }
+
+            updateChildAlpha();
+            super.dispatchDraw(canvas);
+        }
+    }
+}
+\ No newline at end of file