RenderDrawable.java revision 1f158819bc7cf58f97e47fabfaf23b2fb838f2eb 
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                drawableResource.getResourceType() != ResourceType.DRAWABLE) {
73            return Status.ERROR_NOT_A_DRAWABLE.createResult();
74        }
75
76        Drawable d = ResourceHelper.getDrawable(drawableResource, context);
77
78        final Boolean allStates =
79                params.getFlag(RenderParamsFlags.FLAG_KEY_RENDER_ALL_DRAWABLE_STATES);
80        if (allStates == Boolean.TRUE) {
81            final List<BufferedImage> result;
82
83            if (d instanceof StateListDrawable) {
84                result = new ArrayList<BufferedImage>();
85                final StateListDrawable stateList = (StateListDrawable) d;
86                for (int i = 0; i < stateList.getStateCount(); i++) {
87                    final Drawable stateDrawable = stateList.getStateDrawable(i);
88                    result.add(renderImage(hardwareConfig, stateDrawable, context));
89                }
90            } else {
91                result = Collections.singletonList(renderImage(hardwareConfig, d, context));
92            }
93
94            return Status.SUCCESS.createResult(result);
95        } else {
96            BufferedImage image = renderImage(hardwareConfig, d, context);
97            return Status.SUCCESS.createResult(image);
98        }
99    }
100
101    private BufferedImage renderImage(HardwareConfig hardwareConfig, Drawable d,
102            BridgeContext context) {
103        // create a simple FrameLayout
104        FrameLayout content = new FrameLayout(context);
105
106        // get the actual Drawable object to draw
107        content.setBackground(d);
108
109        // set the AttachInfo on the root view.
110        AttachInfo_Accessor.setAttachInfo(content);
111
112
113        // measure
114        int w = d.getIntrinsicWidth();
115        int h = d.getIntrinsicHeight();
116
117        final int screenWidth = hardwareConfig.getScreenWidth();
118        final int screenHeight = hardwareConfig.getScreenHeight();
119
120        if (w == -1 || h == -1) {
121            // Use screen size when either intrinsic width or height isn't available
122            w = screenWidth;
123            h = screenHeight;
124        } else if (w > screenWidth || h > screenHeight) {
125            // If image wouldn't fit to the screen, resize it to avoid cropping.
126
127            // We need to find scale such that scale * w <= screenWidth, scale * h <= screenHeight
128            double scale = Math.min((double) screenWidth / w, (double) screenHeight / h);
129
130            // scale * w / scale * h = w / h, so, proportions are preserved.
131            w = (int) Math.floor(scale * w);
132            h = (int) Math.floor(scale * h);
133        }
134
135        int w_spec = MeasureSpec.makeMeasureSpec(w, MeasureSpec.EXACTLY);
136        int h_spec = MeasureSpec.makeMeasureSpec(h, MeasureSpec.EXACTLY);
137        content.measure(w_spec, h_spec);
138
139        // now do the layout.
140        content.layout(0, 0, w, h);
141
142        // preDraw setup
143        AttachInfo_Accessor.dispatchOnPreDraw(content);
144
145        // draw into a new image
146        BufferedImage image = getImage(w, h);
147
148        // create an Android bitmap around the BufferedImage
149        Bitmap bitmap = Bitmap_Delegate.createBitmap(image,
150                true /*isMutable*/, hardwareConfig.getDensity());
151
152        // create a Canvas around the Android bitmap
153        Canvas canvas = new Canvas(bitmap);
154        canvas.setDensity(hardwareConfig.getDensity().getDpiValue());
155
156        // and draw
157        content.draw(canvas);
158        return image;
159    }
160
161    protected BufferedImage getImage(int w, int h) {
162        BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);
163        Graphics2D gc = image.createGraphics();
164        gc.setComposite(AlphaComposite.Src);
165
166        gc.setColor(new Color(0x00000000, true));
167        gc.fillRect(0, 0, w, h);
168
169        // done
170        gc.dispose();
171
172        return image;
173    }
174
175}
176