Adding holographic outline for paged items (sans widgets).
Fixing possible null ptr exception in Launcher.
Change-Id: Ie625a6503299cf122e5c22852846d59e66f77414
diff --git a/src/com/android/launcher2/PagedViewIcon.java b/src/com/android/launcher2/PagedViewIcon.java
new file mode 100644
index 0000000..e2c22c3
--- /dev/null
+++ b/src/com/android/launcher2/PagedViewIcon.java
@@ -0,0 +1,234 @@
+/*
+ * 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 android.content.Context;
+import android.content.res.Resources;
+import android.graphics.Bitmap;
+import android.graphics.BlurMaskFilter;
+import android.graphics.Canvas;
+import android.graphics.Color;
+import android.graphics.Matrix;
+import android.graphics.Paint;
+import android.graphics.PointF;
+import android.graphics.PorterDuff;
+import android.graphics.PorterDuffXfermode;
+import android.graphics.Rect;
+import android.graphics.Region.Op;
+import android.util.AttributeSet;
+import android.util.DisplayMetrics;
+import android.view.View;
+import android.widget.TextView;
+
+class HolographicOutlineHelper {
+ private final Paint mHolographicPaint = new Paint();
+ private final Paint mBlurPaint = new Paint();
+ private final Paint mErasePaint = new Paint();
+ private static final Matrix mIdentity = new Matrix();
+ private static final float STROKE_WIDTH = 6.0f;
+ private static final float BLUR_FACTOR = 3.5f;
+
+ HolographicOutlineHelper(float density) {
+ mHolographicPaint.setColor(0xFF6699ff);
+ mHolographicPaint.setFilterBitmap(true);
+ mHolographicPaint.setAntiAlias(true);
+ mBlurPaint.setMaskFilter(new BlurMaskFilter(BLUR_FACTOR * density,
+ BlurMaskFilter.Blur.OUTER));
+ mBlurPaint.setFilterBitmap(true);
+ mErasePaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.DST_OUT));
+ mErasePaint.setFilterBitmap(true);
+ mErasePaint.setAntiAlias(true);
+ }
+
+ private 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 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 float viewAlphaInterpolator(float r) {
+ final float pivot = 0.6f;
+ if (r < pivot) {
+ return r/pivot;
+ } else {
+ return 1.0f;
+ }
+ }
+
+ /**
+ * Applies an outline to whatever is currently drawn in the specified bitmap.
+ */
+ void applyOutline(Bitmap srcDst, Canvas srcDstCanvas, PointF offset) {
+ Bitmap mask = srcDst.extractAlpha();
+ Matrix m = new Matrix();
+ final int width = srcDst.getWidth();
+ final int height = srcDst.getHeight();
+ float xScale = STROKE_WIDTH*2.0f/width;
+ float yScale = STROKE_WIDTH*2.0f/height;
+ m.preScale(1+xScale, 1+yScale, (width / 2.0f) + offset.x,
+ (height / 2.0f) + offset.y);
+
+ srcDstCanvas.drawColor(0, PorterDuff.Mode.CLEAR);
+ srcDstCanvas.drawBitmap(mask, m, mHolographicPaint);
+ srcDstCanvas.drawBitmap(mask, mIdentity, mErasePaint);
+ mask.recycle();
+ }
+
+ /**
+ * Applies an blur to whatever is currently drawn in the specified bitmap.
+ */
+ void applyBlur(Bitmap srcDst, Canvas srcDstCanvas) {
+ int[] xy = new int[2];
+ Bitmap mask = srcDst.extractAlpha(mBlurPaint, xy);
+ srcDstCanvas.drawBitmap(mask, xy[0], xy[1], mHolographicPaint);
+ mask.recycle();
+ }
+}
+
+/**
+ * An icon on a PagedView, specifically for items in the launcher's paged view (with compound
+ * drawables on the top).
+ */
+public class PagedViewIcon extends TextView {
+ private static final String TAG = "PagedViewIcon";
+
+ // holographic outline
+ private final Paint mPaint = new Paint();
+ private static HolographicOutlineHelper sHolographicOutlineHelper;
+ private Bitmap mHolographicOutline;
+ private Canvas mHolographicOutlineCanvas;
+ private boolean mIsHolographicUpdatePass;
+ private Rect mDrawableClipRect;
+
+ private int mAlpha;
+ private int mHolographicAlpha;
+
+ public PagedViewIcon(Context context) {
+ this(context, null);
+ }
+
+ public PagedViewIcon(Context context, AttributeSet attrs) {
+ this(context, attrs, 0);
+ }
+
+ public PagedViewIcon(Context context, AttributeSet attrs, int defStyle) {
+ super(context, attrs, defStyle);
+
+ if (sHolographicOutlineHelper == null) {
+ final Resources resources = context.getResources();
+ final DisplayMetrics metrics = resources.getDisplayMetrics();
+ final float density = metrics.density;
+ sHolographicOutlineHelper = new HolographicOutlineHelper(density);
+ }
+ mDrawableClipRect = new Rect();
+
+ setFocusable(true);
+ setBackgroundDrawable(null);
+ }
+
+ @Override
+ public void setAlpha(float alpha) {
+ final float viewAlpha = sHolographicOutlineHelper.viewAlphaInterpolator(alpha);
+ mAlpha = (int) (viewAlpha * 255);
+ final float holographicAlpha = sHolographicOutlineHelper.highlightAlphaInterpolator(alpha);
+ mHolographicAlpha = (int) (holographicAlpha * 255);
+
+ // WORKAROUND: until TextView handles canvas shadow layer alpha itself
+ int sRed = Color.red(mShadowColor);
+ int sGreen = Color.green(mShadowColor);
+ int sBlue = Color.blue(mShadowColor);
+ super.setShadowLayer(mShadowRadius, mShadowDx, mShadowDy, Color.argb(mAlpha, sRed, sGreen,
+ sBlue));
+
+ super.setAlpha(viewAlpha);
+ }
+
+ @Override
+ protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
+ super.onLayout(changed, left, top, right, bottom);
+
+ if (mHolographicOutline == null) {
+ final PointF offset = new PointF(0,
+ -(getCompoundPaddingBottom() + getCompoundPaddingTop())/2.0f);
+
+ // update the clipping rect to be used in the holographic pass below
+ getDrawingRect(mDrawableClipRect);
+ mDrawableClipRect.bottom = getPaddingTop() + getCompoundPaddingTop();
+
+ // set a flag to indicate that we are going to draw the view at full alpha with the text
+ // clipped for the generation of the holographic icon
+ mIsHolographicUpdatePass = true;
+ mHolographicOutline = Bitmap.createBitmap(getMeasuredWidth(), getMeasuredHeight(),
+ Bitmap.Config.ARGB_8888);
+ mHolographicOutlineCanvas = new Canvas(mHolographicOutline);
+ mHolographicOutlineCanvas.concat(getMatrix());
+ draw(mHolographicOutlineCanvas);
+ sHolographicOutlineHelper.applyOutline(mHolographicOutline, mHolographicOutlineCanvas,
+ offset);
+ sHolographicOutlineHelper.applyBlur(mHolographicOutline, mHolographicOutlineCanvas);
+ mIsHolographicUpdatePass = false;
+ }
+ }
+
+ // WORKAROUND: until TextView handles canvas shadow layer alpha itself
+ float mShadowRadius, mShadowDx, mShadowDy;
+ int mShadowColor;
+ @Override
+ public void setShadowLayer(float radius, float dx, float dy, int color) {
+ mShadowRadius = radius;
+ mShadowDx = dx;
+ mShadowDy = dy;
+ mShadowColor = color;
+ super.setShadowLayer(radius, dx, dy, color);
+ }
+
+ @Override
+ protected void onDraw(Canvas canvas) {
+ if (mIsHolographicUpdatePass) {
+ // only clip to the text view (restore its alpha so that we get a proper outline)
+ canvas.save();
+ canvas.clipRect(mDrawableClipRect, Op.REPLACE);
+ super.onSetAlpha(255);
+ super.onDraw(canvas);
+ super.onSetAlpha(mAlpha);
+ canvas.restore();
+ } else {
+ if (mAlpha > 0) {
+ super.onDraw(canvas);
+ }
+ }
+
+ if (!mIsHolographicUpdatePass && mHolographicOutline != null && mHolographicAlpha > 0) {
+ mPaint.setAlpha(mHolographicAlpha);
+ canvas.drawBitmap(mHolographicOutline, 0, 0, mPaint);
+ }
+ }
+}