RenderDrawable.java revision 7f9f99ea11051614a7727dfb9f9578b518e76e3c 
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 static com.android.ide.common.rendering.api.Result.Status.ERROR_UNKNOWN;
20
21import com.android.ide.common.rendering.api.DrawableParams;
22import com.android.ide.common.rendering.api.ResourceValue;
23import com.android.ide.common.rendering.api.Result;
24import com.android.ide.common.rendering.api.Result.Status;
25import com.android.layoutlib.bridge.android.BridgeContext;
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.view.AttachInfo_Accessor;
33import android.view.View.MeasureSpec;
34import android.widget.FrameLayout;
35
36import java.awt.AlphaComposite;
37import java.awt.Color;
38import java.awt.Graphics2D;
39import java.awt.image.BufferedImage;
40import java.io.IOException;
41
42/**
43 * Action to render a given Drawable provided through {@link DrawableParams#getDrawable()}.
44 *
45 * The class only provides a simple {@link #render()} method, but the full life-cycle of the
46 * action must be respected.
47 *
48 * @see RenderAction
49 *
50 */
51public class RenderDrawable extends RenderAction<DrawableParams> {
52
53    public RenderDrawable(DrawableParams params) {
54        super(new DrawableParams(params));
55    }
56
57    public Result render() {
58        checkLock();
59        try {
60            // get the drawable resource value
61            DrawableParams params = getParams();
62            ResourceValue drawableResource = params.getDrawable();
63
64            // resolve it
65            BridgeContext context = getContext();
66            drawableResource = context.getRenderResources().resolveResValue(drawableResource);
67
68            if (drawableResource == null ||
69                    drawableResource.getResourceType() != ResourceType.DRAWABLE) {
70                return Status.ERROR_NOT_A_DRAWABLE.createResult();
71            }
72
73            // create a simple FrameLayout
74            FrameLayout content = new FrameLayout(context);
75
76            // get the actual Drawable object to draw
77            Drawable d = ResourceHelper.getDrawable(drawableResource, context);
78            content.setBackgroundDrawable(d);
79
80            // set the AttachInfo on the root view.
81            AttachInfo_Accessor.setAttachInfo(content);
82
83
84            // measure
85            int w = params.getScreenWidth();
86            int h = params.getScreenHeight();
87            int w_spec = MeasureSpec.makeMeasureSpec(w, MeasureSpec.EXACTLY);
88            int h_spec = MeasureSpec.makeMeasureSpec(h, MeasureSpec.EXACTLY);
89            content.measure(w_spec, h_spec);
90
91            // now do the layout.
92            content.layout(0, 0, w, h);
93
94            // preDraw setup
95            AttachInfo_Accessor.dispatchOnPreDraw(content);
96
97            // draw into a new image
98            BufferedImage image = getImage(w, h);
99
100            // create an Android bitmap around the BufferedImage
101            Bitmap bitmap = Bitmap_Delegate.createBitmap(image,
102                    true /*isMutable*/, params.getDensity());
103
104            // create a Canvas around the Android bitmap
105            Canvas canvas = new Canvas(bitmap);
106            canvas.setDensity(params.getDensity().getDpiValue());
107
108            // and draw
109            content.draw(canvas);
110
111            return Status.SUCCESS.createResult(image);
112        } catch (IOException e) {
113            return ERROR_UNKNOWN.createResult(e.getMessage(), e);
114        }
115    }
116
117    protected BufferedImage getImage(int w, int h) {
118        BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);
119        Graphics2D gc = image.createGraphics();
120        gc.setComposite(AlphaComposite.Src);
121
122        gc.setColor(new Color(0x00000000, true));
123        gc.fillRect(0, 0, w, h);
124
125        // done
126        gc.dispose();
127
128        return image;
129    }
130
131}
132