RenderDrawable.java revision 4b0fe7f14bb36769ef30c59c407bd6ed5b3d5cf7 
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;
41import java.util.ArrayList;
42import java.util.Collections;
43import java.util.List;
44
45/**
46 * Action to render a given Drawable provided through {@link DrawableParams#getDrawable()}.
47 *
48 * The class only provides a simple {@link #render()} method, but the full life-cycle of the
49 * action must be respected.
50 *
51 * @see RenderAction
52 *
53 */
54public class RenderDrawable extends RenderAction<DrawableParams> {
55
56    public RenderDrawable(DrawableParams params) {
57        super(new DrawableParams(params));
58    }
59
60    public Result render() {
61        checkLock();
62        // get the drawable resource value
63        DrawableParams params = getParams();
64        HardwareConfig hardwareConfig = params.getHardwareConfig();
65        ResourceValue drawableResource = params.getDrawable();
66
67        // resolve it
68        BridgeContext context = getContext();
69        drawableResource = context.getRenderResources().resolveResValue(drawableResource);
70
71        if (drawableResource == null) {
72            return Status.ERROR_NOT_A_DRAWABLE.createResult();
73        }
74
75        ResourceType resourceType = drawableResource.getResourceType();
76        if (resourceType != ResourceType.DRAWABLE && resourceType != ResourceType.MIPMAP) {
77            return Status.ERROR_NOT_A_DRAWABLE.createResult();
78        }
79
80        Drawable d = ResourceHelper.getDrawable(drawableResource, context);
81
82        final Boolean allStates =
83                params.getFlag(RenderParamsFlags.FLAG_KEY_RENDER_ALL_DRAWABLE_STATES);
84        if (allStates == Boolean.TRUE) {
85            final List<BufferedImage> result;
86
87            if (d instanceof StateListDrawable) {
88                result = new ArrayList<BufferedImage>();
89                final StateListDrawable stateList = (StateListDrawable) d;
90                for (int i = 0; i < stateList.getStateCount(); i++) {
91                    final Drawable stateDrawable = stateList.getStateDrawable(i);
92                    result.add(renderImage(hardwareConfig, stateDrawable, context));
93                }
94            } else {
95                result = Collections.singletonList(renderImage(hardwareConfig, d, context));
96            }
97
98            return Status.SUCCESS.createResult(result);
99        } else {
100            BufferedImage image = renderImage(hardwareConfig, d, context);
101            return Status.SUCCESS.createResult(image);
102        }
103    }
104
105    private BufferedImage renderImage(HardwareConfig hardwareConfig, Drawable d,
106            BridgeContext context) {
107        // create a simple FrameLayout
108        FrameLayout content = new FrameLayout(context);
109
110        // get the actual Drawable object to draw
111        content.setBackground(d);
112
113        // set the AttachInfo on the root view.
114        AttachInfo_Accessor.setAttachInfo(content);
115
116
117        // measure
118        int w = d.getIntrinsicWidth();
119        int h = d.getIntrinsicHeight();
120
121        final int screenWidth = hardwareConfig.getScreenWidth();
122        final int screenHeight = hardwareConfig.getScreenHeight();
123
124        if (w == -1 || h == -1) {
125            // Use screen size when either intrinsic width or height isn't available
126            w = screenWidth;
127            h = screenHeight;
128        } else if (w > screenWidth || h > screenHeight) {
129            // If image wouldn't fit to the screen, resize it to avoid cropping.
130
131            // We need to find scale such that scale * w <= screenWidth, scale * h <= screenHeight
132            double scale = Math.min((double) screenWidth / w, (double) screenHeight / h);
133
134            // scale * w / scale * h = w / h, so, proportions are preserved.
135            w = (int) Math.floor(scale * w);
136            h = (int) Math.floor(scale * h);
137        }
138
139        int w_spec = MeasureSpec.makeMeasureSpec(w, MeasureSpec.EXACTLY);
140        int h_spec = MeasureSpec.makeMeasureSpec(h, MeasureSpec.EXACTLY);
141        content.measure(w_spec, h_spec);
142
143        // now do the layout.
144        content.layout(0, 0, w, h);
145
146        // preDraw setup
147        AttachInfo_Accessor.dispatchOnPreDraw(content);
148
149        // draw into a new image
150        BufferedImage image = getImage(w, h);
151
152        // create an Android bitmap around the BufferedImage
153        Bitmap bitmap = Bitmap_Delegate.createBitmap(image,
154                true /*isMutable*/, hardwareConfig.getDensity());
155
156        // create a Canvas around the Android bitmap
157        Canvas canvas = new Canvas(bitmap);
158        canvas.setDensity(hardwareConfig.getDensity().getDpiValue());
159
160        // and draw
161        content.draw(canvas);
162        return image;
163    }
164
165    protected BufferedImage getImage(int w, int h) {
166        BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);
167        Graphics2D gc = image.createGraphics();
168        gc.setComposite(AlphaComposite.Src);
169
170        gc.setColor(new Color(0x00000000, true));
171        gc.fillRect(0, 0, w, h);
172
173        // done
174        gc.dispose();
175
176        return image;
177    }
178
179}
180