RenderDrawable.java revision fd18f573280bbbcc549b35b548580a562bd960e2 
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.layoutlib.bridge.android.BridgeWindow;
27import com.android.layoutlib.bridge.android.BridgeWindowSession;
28import com.android.resources.ResourceType;
29
30import android.graphics.Bitmap;
31import android.graphics.Bitmap_Delegate;
32import android.graphics.Canvas;
33import android.graphics.drawable.Drawable;
34import android.os.Handler;
35import android.view.View;
36import android.view.View.AttachInfo;
37import android.view.View.MeasureSpec;
38import android.widget.FrameLayout;
39
40import java.awt.AlphaComposite;
41import java.awt.Color;
42import java.awt.Graphics2D;
43import java.awt.image.BufferedImage;
44import java.io.IOException;
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        try {
64            // get the drawable resource value
65            DrawableParams params = getParams();
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            // create a simple FrameLayout
78            FrameLayout content = new FrameLayout(context);
79
80            // get the actual Drawable object to draw
81            Drawable d = ResourceHelper.getDrawable(drawableResource, context);
82            content.setBackgroundDrawable(d);
83
84            // set the AttachInfo on the root view.
85            AttachInfo info = new AttachInfo(new BridgeWindowSession(), new BridgeWindow(),
86                    new Handler(), null);
87            info.mHasWindowFocus = true;
88            info.mWindowVisibility = View.VISIBLE;
89            info.mInTouchMode = false; // this is so that we can display selections.
90            info.mHardwareAccelerated = false;
91            content.dispatchAttachedToWindow(info, 0);
92
93
94            // measure
95            int w = params.getScreenWidth();
96            int h = params.getScreenHeight();
97            int w_spec = MeasureSpec.makeMeasureSpec(w, MeasureSpec.EXACTLY);
98            int h_spec = MeasureSpec.makeMeasureSpec(h, MeasureSpec.EXACTLY);
99            content.measure(w_spec, h_spec);
100
101            // now do the layout.
102            content.layout(0, 0, w, h);
103
104            // preDraw setup
105            content.mAttachInfo.mTreeObserver.dispatchOnPreDraw();
106
107            // draw into a new image
108            BufferedImage image = getImage(w, h);
109
110            // create an Android bitmap around the BufferedImage
111            Bitmap bitmap = Bitmap_Delegate.createBitmap(image,
112                    true /*isMutable*/, params.getDensity());
113
114            // create a Canvas around the Android bitmap
115            Canvas canvas = new Canvas(bitmap);
116            canvas.setDensity(params.getDensity().getDpiValue());
117
118            // and draw
119            content.draw(canvas);
120
121            return Status.SUCCESS.createResult(image);
122        } catch (IOException e) {
123            return ERROR_UNKNOWN.createResult(e.getMessage(), e);
124        }
125    }
126
127    protected BufferedImage getImage(int w, int h) {
128        BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);
129        Graphics2D gc = image.createGraphics();
130        gc.setComposite(AlphaComposite.Src);
131
132        gc.setColor(new Color(0x00000000, true));
133        gc.fillRect(0, 0, w, h);
134
135        // done
136        gc.dispose();
137
138        return image;
139    }
140
141}
142