1/*
2 * Copyright (C) 2017 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.launcher3.views;
18
19import android.content.Context;
20import android.content.res.TypedArray;
21import android.graphics.Canvas;
22import android.graphics.Color;
23import android.support.v4.graphics.ColorUtils;
24import android.util.AttributeSet;
25import android.widget.TextView;
26
27import com.android.launcher3.BubbleTextView;
28import com.android.launcher3.R;
29
30/**
31 * Extension of {@link BubbleTextView} which draws two shadows on the text (ambient and key shadows}
32 */
33public class DoubleShadowBubbleTextView extends BubbleTextView {
34
35    private final ShadowInfo mShadowInfo;
36
37    public DoubleShadowBubbleTextView(Context context) {
38        this(context, null);
39    }
40
41    public DoubleShadowBubbleTextView(Context context, AttributeSet attrs) {
42        this(context, attrs, 0);
43    }
44
45    public DoubleShadowBubbleTextView(Context context, AttributeSet attrs, int defStyle) {
46        super(context, attrs, defStyle);
47        mShadowInfo = new ShadowInfo(context, attrs, defStyle);
48        setShadowLayer(mShadowInfo.ambientShadowBlur, 0, 0, mShadowInfo.ambientShadowColor);
49    }
50
51    @Override
52    public void onDraw(Canvas canvas) {
53        // If text is transparent or shadow alpha is 0, don't draw any shadow
54        if (mShadowInfo.skipDoubleShadow(this)) {
55            super.onDraw(canvas);
56            return;
57        }
58        int alpha = Color.alpha(getCurrentTextColor());
59
60        // We enhance the shadow by drawing the shadow twice
61        getPaint().setShadowLayer(mShadowInfo.ambientShadowBlur, 0, 0,
62                ColorUtils.setAlphaComponent(mShadowInfo.ambientShadowColor, alpha));
63
64        drawWithoutBadge(canvas);
65        canvas.save();
66        canvas.clipRect(getScrollX(), getScrollY() + getExtendedPaddingTop(),
67                getScrollX() + getWidth(),
68                getScrollY() + getHeight());
69
70        getPaint().setShadowLayer(mShadowInfo.keyShadowBlur, 0.0f, mShadowInfo.keyShadowOffset,
71                ColorUtils.setAlphaComponent(mShadowInfo.keyShadowColor, alpha));
72        drawWithoutBadge(canvas);
73        canvas.restore();
74
75        drawBadgeIfNecessary(canvas);
76    }
77
78    public static class ShadowInfo {
79        public final float ambientShadowBlur;
80        public final int ambientShadowColor;
81
82        public final float keyShadowBlur;
83        public final float keyShadowOffset;
84        public final int keyShadowColor;
85
86        public ShadowInfo(Context c, AttributeSet attrs, int defStyle) {
87
88            TypedArray a = c.obtainStyledAttributes(
89                    attrs, R.styleable.ShadowInfo, defStyle, 0);
90
91            ambientShadowBlur = a.getDimension(R.styleable.ShadowInfo_ambientShadowBlur, 0);
92            ambientShadowColor = a.getColor(R.styleable.ShadowInfo_ambientShadowColor, 0);
93
94            keyShadowBlur = a.getDimension(R.styleable.ShadowInfo_keyShadowBlur, 0);
95            keyShadowOffset = a.getDimension(R.styleable.ShadowInfo_keyShadowOffset, 0);
96            keyShadowColor = a.getColor(R.styleable.ShadowInfo_keyShadowColor, 0);
97            a.recycle();
98        }
99
100        public boolean skipDoubleShadow(TextView textView) {
101            int textAlpha = Color.alpha(textView.getCurrentTextColor());
102            int keyShadowAlpha = Color.alpha(keyShadowColor);
103            int ambientShadowAlpha = Color.alpha(ambientShadowColor);
104            if (textAlpha == 0 || (keyShadowAlpha == 0 && ambientShadowAlpha == 0)) {
105                textView.getPaint().clearShadowLayer();
106                return true;
107            } else if (ambientShadowAlpha > 0) {
108                textView.getPaint().setShadowLayer(ambientShadowBlur, 0, 0,
109                        ColorUtils.setAlphaComponent(ambientShadowColor, textAlpha));
110                return true;
111            } else if (keyShadowAlpha > 0) {
112                textView.getPaint().setShadowLayer(keyShadowBlur, 0.0f, keyShadowOffset,
113                        ColorUtils.setAlphaComponent(keyShadowColor, textAlpha));
114                return true;
115            } else {
116                return false;
117            }
118        }
119    }
120}
121