1 files changed, 206 insertions, 0 deletions
diff --git a/src/com/android/launcher3/allapps/SectionDecorationHandler.java b/src/com/android/launcher3/allapps/SectionDecorationHandler.java
new file mode 100644
index 0000000000..f79b82cebb
--- /dev/null
+++ b/src/com/android/launcher3/allapps/SectionDecorationHandler.java
@@ -0,0 +1,206 @@
+/*
+ * Copyright (C) 2023 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.launcher3.allapps;
+
+import android.content.Context;
+import android.graphics.Canvas;
+import android.graphics.Paint;
+import android.graphics.Path;
+import android.graphics.RectF;
+import android.graphics.drawable.GradientDrawable;
+import android.graphics.drawable.InsetDrawable;
+import android.view.View;
+
+import androidx.annotation.Nullable;
+import androidx.core.content.ContextCompat;
+
+import com.android.launcher3.R;
+import com.android.launcher3.util.Themes;
+
+public class SectionDecorationHandler {
+
+    protected final Path mTmpPath = new Path();
+    protected final RectF mTmpRect = new RectF();
+
+    protected final int mCornerGroupRadius;
+    protected final int mCornerResultRadius;
+    protected final RectF mBounds = new RectF();
+    protected final Paint mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
+
+    protected final int mFocusAlpha = 255; // main focused item alpha
+    protected int mFillColor; // grouping color
+    protected int mFocusColor; // main focused item color
+    protected float mFillSpacing;
+    protected int mInlineRadius;
+    protected Context mContext;
+    protected float[] mCorners;
+    protected int mFillAlpha;
+    protected boolean mIsTopLeftRound;
+    protected boolean mIsTopRightRound;
+    protected boolean mIsBottomLeftRound;
+    protected boolean mIsBottomRightRound;
+    protected boolean mIsBottomRound;
+    protected boolean mIsTopRound;
+
+    public SectionDecorationHandler(Context context, int fillAlpha, boolean isTopLeftRound,
+            boolean isTopRightRound, boolean isBottomLeftRound,
+            boolean isBottomRightRound) {
+
+        mContext = context;
+        mFillAlpha = fillAlpha;
+        mFocusColor = ContextCompat.getColor(context,
+                R.color.material_color_surface_bright); // UX recommended
+        mFillColor = ContextCompat.getColor(context,
+                R.color.material_color_surface_container_high); // UX recommended
+
+        mIsTopLeftRound = isTopLeftRound;
+        mIsTopRightRound = isTopRightRound;
+        mIsBottomLeftRound = isBottomLeftRound;
+        mIsBottomRightRound = isBottomRightRound;
+        mIsBottomRound = mIsBottomLeftRound && mIsBottomRightRound;
+        mIsTopRound = mIsTopLeftRound && mIsTopRightRound;
+
+        mCornerGroupRadius = context.getResources().getDimensionPixelSize(
+                R.dimen.all_apps_recycler_view_decorator_group_radius);
+        mCornerResultRadius = context.getResources().getDimensionPixelSize(
+                R.dimen.all_apps_recycler_view_decorator_result_radius);
+
+        mInlineRadius = 0;
+        mFillSpacing = 0;
+        initCorners();
+    }
+
+    protected void initCorners() {
+        mCorners = new float[]{
+                mIsTopLeftRound ? mCornerGroupRadius : 0,
+                mIsTopLeftRound ? mCornerGroupRadius : 0, // Top left radius in px
+                mIsTopRightRound ? mCornerGroupRadius : 0,
+                mIsTopRightRound ? mCornerGroupRadius : 0, // Top right radius in px
+                mIsBottomRightRound ? mCornerGroupRadius : 0,
+                mIsBottomRightRound ? mCornerGroupRadius : 0, // Bottom right
+                mIsBottomLeftRound ? mCornerGroupRadius : 0,
+                mIsBottomLeftRound ? mCornerGroupRadius : 0 // Bottom left
+        };
+    }
+
+    protected void setFillAlpha(int fillAlpha) {
+        mFillAlpha = fillAlpha;
+        mPaint.setAlpha(mFillAlpha);
+    }
+
+    protected void onFocusDraw(Canvas canvas, @Nullable View view) {
+        if (view == null) {
+            return;
+        }
+        mPaint.setColor(mFillColor);
+        mPaint.setAlpha(mFillAlpha);
+        int scaledHeight = (int) (view.getHeight() * view.getScaleY());
+        mBounds.set(view.getLeft(), view.getY(), view.getRight(), view.getY() + scaledHeight);
+        onDraw(canvas);
+    }
+
+    protected void onDraw(Canvas canvas) {
+        mTmpPath.reset();
+        mTmpRect.set(mBounds.left + mFillSpacing,
+                mBounds.top + mFillSpacing,
+                mBounds.right - mFillSpacing,
+                mBounds.bottom - mFillSpacing);
+        mTmpPath.addRoundRect(mTmpRect, mCorners, Path.Direction.CW);
+        canvas.drawPath(mTmpPath, mPaint);
+    }
+
+    /** Sets the right background drawable to the view based on the give decoration info. */
+    public void applyBackground(View view, Context context,
+           @Nullable SectionDecorationInfo decorationInfo, boolean isHighlighted) {
+        int inset = context.getResources().getDimensionPixelSize(
+                R.dimen.all_apps_recycler_view_decorator_padding);
+        float radiusBottom = (decorationInfo == null || decorationInfo.isBottomRound()) ?
+                mCornerGroupRadius : mCornerResultRadius;
+        float radiusTop =
+                (decorationInfo == null || decorationInfo.isTopRound()) ?
+                        mCornerGroupRadius : mCornerResultRadius;
+        int color = isHighlighted ? mFocusColor : mFillColor;
+
+        GradientDrawable shape = new GradientDrawable();
+        shape.setShape(GradientDrawable.RECTANGLE);
+        shape.setCornerRadii(new float[] {
+                radiusTop, radiusTop, // top-left
+                radiusTop, radiusTop, // top-right
+                radiusBottom, radiusBottom, // bottom-right
+                radiusBottom, radiusBottom // bottom-left
+        });
+        shape.setColor(color);
+
+        // Setting the background resets the padding, so we cache it and reset it afterwards.
+        int paddingLeft = view.getPaddingLeft();
+        int paddingTop = view.getPaddingTop();
+        int paddingRight = view.getPaddingRight();
+        int paddingBottom = view.getPaddingBottom();
+
+        view.setBackground(new InsetDrawable(shape, inset));
+
+        view.setPadding(paddingLeft, paddingTop, paddingRight, paddingBottom);
+    }
+
+    /**
+     * Section decorator that combines views and draws a single block decoration
+     */
+    public static class UnionDecorationHandler extends SectionDecorationHandler {
+
+        private final int mPaddingLeft;
+        private final int mPaddingRight;
+
+        public UnionDecorationHandler(
+                SectionDecorationHandler decorationHandler,
+                int paddingLeft, int paddingRight) {
+            super(decorationHandler.mContext, decorationHandler.mFillAlpha,
+                    decorationHandler.mIsTopLeftRound, decorationHandler.mIsTopRightRound,
+                    decorationHandler.mIsBottomLeftRound, decorationHandler.mIsBottomRightRound);
+            mPaddingLeft = paddingLeft;
+            mPaddingRight = paddingRight;
+        }
+
+        /**
+         * Expands decoration bounds to include child {@link PrivateAppsSectionDecorator}
+         */
+        public void addChild(SectionDecorationHandler child, View view, boolean applyBackground) {
+            int scaledHeight = (int) (view.getHeight() * view.getScaleY());
+            mBounds.union(view.getLeft(), view.getY(),
+                    view.getRight(), view.getY() + scaledHeight);
+            if (applyBackground) {
+                applyBackground(view, mContext, null, false);
+            }
+            mIsBottomRound |= child.mIsBottomRound;
+            mIsBottomLeftRound |= child.mIsBottomLeftRound;
+            mIsBottomRightRound |= child.mIsBottomRightRound;
+            mIsTopRound |= child.mIsTopRound;
+            mIsTopLeftRound |= child.mIsTopLeftRound;
+            mIsTopRightRound |= child.mIsTopRightRound;
+        }
+
+        /**
+         * Draws group decoration to canvas
+         */
+        public void onGroupDecorate(Canvas canvas) {
+            initCorners();
+            mBounds.left = mPaddingLeft;
+            mBounds.right = canvas.getWidth() - mPaddingRight;
+            mPaint.setColor(mFillColor);
+            mPaint.setAlpha(mFillAlpha);
+            onDraw(canvas);
+        }
+    }
+}