RenderDrawable.java revision 681c7d142a6d25d3215d5f879074cd4359c6f106 
1/*
2 * Copyright (C) 2011 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.layoutlib.bridge.impl;
18
19import com.android.ide.common.rendering.api.DrawableParams;
20import com.android.ide.common.rendering.api.HardwareConfig;
21import com.android.ide.common.rendering.api.ResourceValue;
22import com.android.ide.common.rendering.api.Result;
23import com.android.ide.common.rendering.api.Result.Status;
24import com.android.layoutlib.bridge.android.BridgeContext;
25import com.android.layoutlib.bridge.android.RenderParamsFlags;
26import com.android.resources.ResourceType;
27
28import android.graphics.Bitmap;
29import android.graphics.Bitmap_Delegate;
30import android.graphics.Canvas;
31import android.graphics.drawable.Drawable;
32import android.graphics.drawable.StateListDrawable;
33import android.view.AttachInfo_Accessor;
34import android.view.View.MeasureSpec;
35import android.widget.FrameLayout;
36
37import java.awt.AlphaComposite;
38import java.awt.Color;
39import java.awt.Graphics2D;
40import java.awt.image.BufferedImage;
41
42import java.util.ArrayList;
43import java.util.Collections;
44import java.util.List;
45
46/**
47 * Action to render a given Drawable provided through {@link DrawableParams#getDrawable()}.
48 *
49 * The class only provides a simple {@link #render()} method, but the full life-cycle of the
50 * action must be respected.
51 *
52 * @see RenderAction
53 *
54 */
55public class RenderDrawable extends RenderAction<DrawableParams> {
56
57    public RenderDrawable(DrawableParams params) {
58        super(new DrawableParams(params));
59    }
60
61    public Result render() {
62        checkLock();
63        // get the drawable resource value
64        DrawableParams params = getParams();
65        HardwareConfig hardwareConfig = params.getHardwareConfig();
66        ResourceValue drawableResource = params.getDrawable();
67
68        // resolve it
69        BridgeContext context = getContext();
70        drawableResource = context.getRenderResources().resolveResValue(drawableResource);
71
72        if (drawableResource == null ||
73                drawableResource.getResourceType() != ResourceType.DRAWABLE) {
74            return Status.ERROR_NOT_A_DRAWABLE.createResult();
75        }
76
77        Drawable d = ResourceHelper.getDrawable(drawableResource, context);
78
79        final Boolean allStates =
80                params.getFlag(RenderParamsFlags.FLAG_KEY_RENDER_ALL_DRAWABLE_STATES);
81        if (allStates == Boolean.TRUE) {
82            final List<BufferedImage> result;
83
84            if (d instanceof StateListDrawable) {
85                result = new ArrayList<BufferedImage>();
86                final StateListDrawable stateList = (StateListDrawable) d;
87                for (int i = 0; i < stateList.getStateCount(); i++) {
88                    final Drawable stateDrawable = stateList.getStateDrawable(i);
89                    result.add(renderImage(hardwareConfig, stateDrawable, context));
90                }
91            } else {
92                result = Collections.singletonList(renderImage(hardwareConfig, d, context));
93            }
94
95            return Status.SUCCESS.createResult(result);
96        } else {
97            BufferedImage image = renderImage(hardwareConfig, d, context);
98            return Status.SUCCESS.createResult(image);
99        }
100    }
101
102    private BufferedImage renderImage(HardwareConfig hardwareConfig, Drawable d,
103            BridgeContext context) {
104        // create a simple FrameLayout
105        FrameLayout content = new FrameLayout(context);
106
107        // get the actual Drawable object to draw
108        content.setBackground(d);
109
110        // set the AttachInfo on the root view.
111        AttachInfo_Accessor.setAttachInfo(content);
112
113
114        // measure
115        int w = d.getIntrinsicWidth();
116        int h = d.getIntrinsicHeight();
117
118        final int screenWidth = hardwareConfig.getScreenWidth();
119        final int screenHeight = hardwareConfig.getScreenHeight();
120
121        if (w == -1 || h == -1) {
122            // Use screen size when either intrinsic width or height isn't available
123            w = screenWidth;
124            h = screenHeight;
125        } else if (w > screenWidth || h > screenHeight) {
126            // If image wouldn't fit to the screen, resize it to avoid cropping.
127
128            // We need to find scale such that scale * w <= screenWidth, scale * h <= screenHeight
129            double scale = Math.min((double) screenWidth / w, (double) screenHeight / h);
130
131            // scale * w / scale * h = w / h, so, proportions are preserved.
132            w = (int) Math.floor(scale * w);
133            h = (int) Math.floor(scale * h);
134        }
135
136        int w_spec = MeasureSpec.makeMeasureSpec(w, MeasureSpec.EXACTLY);
137        int h_spec = MeasureSpec.makeMeasureSpec(h, MeasureSpec.EXACTLY);
138        content.measure(w_spec, h_spec);
139
140        // now do the layout.
141        content.layout(0, 0, w, h);
142
143        // preDraw setup
144        AttachInfo_Accessor.dispatchOnPreDraw(content);
145
146        // draw into a new image
147        BufferedImage image = getImage(w, h);
148
149        // create an Android bitmap around the BufferedImage
150        Bitmap bitmap = Bitmap_Delegate.createBitmap(image,
151                true /*isMutable*/, hardwareConfig.getDensity());
152
153        // create a Canvas around the Android bitmap
154        Canvas canvas = new Canvas(bitmap);
155        canvas.setDensity(hardwareConfig.getDensity().getDpiValue());
156
157        // and draw
158        content.draw(canvas);
159        return image;
160    }
161
162    protected BufferedImage getImage(int w, int h) {
163        BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);
164        Graphics2D gc = image.createGraphics();
165        gc.setComposite(AlphaComposite.Src);
166
167        gc.setColor(new Color(0x00000000, true));
168        gc.fillRect(0, 0, w, h);
169
170        // done
171        gc.dispose();
172
173        return image;
174    }
175
176}
177