1/*
2 * Copyright (C) 2008 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 android.graphics.drawable;
18
19import android.graphics.*;
20import android.content.res.Resources;
21import android.content.res.TypedArray;
22import android.util.AttributeSet;
23import android.view.ViewDebug;
24import org.xmlpull.v1.XmlPullParser;
25import org.xmlpull.v1.XmlPullParserException;
26
27import java.io.IOException;
28
29/**
30 * A specialized Drawable that fills the Canvas with a specified color.
31 * Note that a ColorDrawable ignores the ColorFilter.
32 *
33 * <p>It can be defined in an XML file with the <code>&lt;color></code> element.</p>
34 *
35 * @attr ref android.R.styleable#ColorDrawable_color
36 */
37public class ColorDrawable extends Drawable {
38    @ViewDebug.ExportedProperty(deepExport = true, prefix = "state_")
39    private ColorState mState;
40    private final Paint mPaint = new Paint();
41    private boolean mMutated;
42
43    /**
44     * Creates a new black ColorDrawable.
45     */
46    public ColorDrawable() {
47        this(null);
48    }
49
50    /**
51     * Creates a new ColorDrawable with the specified color.
52     *
53     * @param color The color to draw.
54     */
55    public ColorDrawable(int color) {
56        this(null);
57        setColor(color);
58    }
59
60    private ColorDrawable(ColorState state) {
61        mState = new ColorState(state);
62    }
63
64    @Override
65    public int getChangingConfigurations() {
66        return super.getChangingConfigurations() | mState.mChangingConfigurations;
67    }
68
69    /**
70     * A mutable BitmapDrawable still shares its Bitmap with any other Drawable
71     * that comes from the same resource.
72     *
73     * @return This drawable.
74     */
75    @Override
76    public Drawable mutate() {
77        if (!mMutated && super.mutate() == this) {
78            mState = new ColorState(mState);
79            mMutated = true;
80        }
81        return this;
82    }
83
84    @Override
85    public void draw(Canvas canvas) {
86        if ((mState.mUseColor >>> 24) != 0) {
87            mPaint.setColor(mState.mUseColor);
88            canvas.drawRect(getBounds(), mPaint);
89        }
90    }
91
92    /**
93     * Gets the drawable's color value.
94     *
95     * @return int The color to draw.
96     */
97    public int getColor() {
98        return mState.mUseColor;
99    }
100
101    /**
102     * Sets the drawable's color value. This action will clobber the results of prior calls to
103     * {@link #setAlpha(int)} on this object, which side-affected the underlying color.
104     *
105     * @param color The color to draw.
106     */
107    public void setColor(int color) {
108        if (mState.mBaseColor != color || mState.mUseColor != color) {
109            invalidateSelf();
110            mState.mBaseColor = mState.mUseColor = color;
111        }
112    }
113
114    /**
115     * Returns the alpha value of this drawable's color.
116     *
117     * @return A value between 0 and 255.
118     */
119    @Override
120    public int getAlpha() {
121        return mState.mUseColor >>> 24;
122    }
123
124    /**
125     * Sets the color's alpha value.
126     *
127     * @param alpha The alpha value to set, between 0 and 255.
128     */
129    public void setAlpha(int alpha) {
130        alpha += alpha >> 7;   // make it 0..256
131        int baseAlpha = mState.mBaseColor >>> 24;
132        int useAlpha = baseAlpha * alpha >> 8;
133        int oldUseColor = mState.mUseColor;
134        mState.mUseColor = (mState.mBaseColor << 8 >>> 8) | (useAlpha << 24);
135        if (oldUseColor != mState.mUseColor) {
136            invalidateSelf();
137        }
138    }
139
140    /**
141     * Setting a color filter on a ColorDrawable has no effect.
142     *
143     * @param colorFilter Ignore.
144     */
145    public void setColorFilter(ColorFilter colorFilter) {
146    }
147
148    public int getOpacity() {
149        switch (mState.mUseColor >>> 24) {
150            case 255:
151                return PixelFormat.OPAQUE;
152            case 0:
153                return PixelFormat.TRANSPARENT;
154        }
155        return PixelFormat.TRANSLUCENT;
156    }
157
158    @Override
159    public void inflate(Resources r, XmlPullParser parser, AttributeSet attrs)
160            throws XmlPullParserException, IOException {
161        super.inflate(r, parser, attrs);
162
163        TypedArray a = r.obtainAttributes(attrs, com.android.internal.R.styleable.ColorDrawable);
164
165        int color = mState.mBaseColor;
166        color = a.getColor(com.android.internal.R.styleable.ColorDrawable_color, color);
167        mState.mBaseColor = mState.mUseColor = color;
168
169        a.recycle();
170    }
171
172    @Override
173    public ConstantState getConstantState() {
174        mState.mChangingConfigurations = getChangingConfigurations();
175        return mState;
176    }
177
178    final static class ColorState extends ConstantState {
179        int mBaseColor; // base color, independent of setAlpha()
180        @ViewDebug.ExportedProperty
181        int mUseColor;  // basecolor modulated by setAlpha()
182        int mChangingConfigurations;
183
184        ColorState(ColorState state) {
185            if (state != null) {
186                mBaseColor = state.mBaseColor;
187                mUseColor = state.mUseColor;
188                mChangingConfigurations = state.mChangingConfigurations;
189            }
190        }
191
192        @Override
193        public Drawable newDrawable() {
194            return new ColorDrawable(this);
195        }
196
197        @Override
198        public Drawable newDrawable(Resources res) {
199            return new ColorDrawable(this);
200        }
201
202        @Override
203        public int getChangingConfigurations() {
204            return mChangingConfigurations;
205        }
206    }
207}
208