WebViewDelegate.java revision 53f256948724b8d4009d8a8a47da96a06402f9a2 
1/*
2 * Copyright (C) 2014 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 android.webkit;
18
19import android.app.ActivityThread;
20import android.app.Application;
21import android.content.Context;
22import android.content.res.Resources;
23import android.graphics.Canvas;
24import android.net.http.ErrorStrings;
25import android.os.SystemProperties;
26import android.os.Trace;
27import android.util.SparseArray;
28import android.view.HardwareCanvas;
29import android.view.View;
30import android.view.ViewRootImpl;
31
32/**
33 * Delegate used by the WebView provider implementation to access
34 * the required framework functionality needed to implement a {@link WebView}.
35 *
36 * @hide
37 */
38public final class WebViewDelegate {
39
40    /* package */ WebViewDelegate() { }
41
42    /**
43     * Listener that gets notified whenever tracing has been enabled/disabled.
44     */
45    public interface OnTraceEnabledChangeListener {
46        void onTraceEnabledChange(boolean enabled);
47    }
48
49    /**
50     * Register a callback to be invoked when tracing for the WebView component has been
51     * enabled/disabled.
52     */
53    public void setOnTraceEnabledChangeListener(final OnTraceEnabledChangeListener listener) {
54        SystemProperties.addChangeCallback(new Runnable() {
55            @Override
56            public void run() {
57                listener.onTraceEnabledChange(isTraceTagEnabled());
58            }
59        });
60    }
61
62    /**
63     * Returns true if the WebView trace tag is enabled and false otherwise.
64     */
65    public boolean isTraceTagEnabled() {
66        return Trace.isTagEnabled(Trace.TRACE_TAG_WEBVIEW);
67    }
68
69    /**
70     * Returns true if the draw GL functor can be invoked (see {@link #invokeDrawGlFunctor})
71     * and false otherwise.
72     */
73    public boolean canInvokeDrawGlFunctor(View containerView) {
74        ViewRootImpl viewRootImpl = containerView.getViewRootImpl();
75         // viewRootImpl can be null during teardown when window is leaked.
76        return viewRootImpl != null;
77    }
78
79    /**
80     * Invokes the draw GL functor. If waitForCompletion is false the functor
81     * may be invoked asynchronously.
82     *
83     * @param nativeDrawGLFunctor the pointer to the native functor that implements
84     *        system/core/include/utils/Functor.h
85     */
86    public void invokeDrawGlFunctor(View containerView, long nativeDrawGLFunctor,
87            boolean waitForCompletion) {
88        ViewRootImpl viewRootImpl = containerView.getViewRootImpl();
89        viewRootImpl.invokeFunctor(nativeDrawGLFunctor, waitForCompletion);
90    }
91
92    /**
93     * Calls the function specified with the nativeDrawGLFunctor functor pointer. This
94     * functionality is used by the WebView for calling into their renderer from the
95     * framework display lists.
96     *
97     * @param canvas a hardware accelerated canvas (see {@link Canvas#isHardwareAccelerated()})
98     * @param nativeDrawGLFunctor the pointer to the native functor that implements
99     *        system/core/include/utils/Functor.h
100     * @throws IllegalArgumentException if the canvas is not hardware accelerated
101     */
102    public void callDrawGlFunction(Canvas canvas, long nativeDrawGLFunctor) {
103        if (!(canvas instanceof HardwareCanvas)) {
104            // Canvas#isHardwareAccelerated() is only true for subclasses of HardwareCanvas.
105            throw new IllegalArgumentException(canvas.getClass().getName()
106                    + " is not hardware accelerated");
107        }
108        ((HardwareCanvas) canvas).callDrawGLFunction(nativeDrawGLFunctor);
109    }
110
111    /**
112     * Detaches the draw GL functor.
113     *
114     * @param nativeDrawGLFunctor the pointer to the native functor that implements
115     *        system/core/include/utils/Functor.h
116     */
117    public void detachDrawGlFunctor(View containerView, long nativeDrawGLFunctor) {
118        ViewRootImpl viewRootImpl = containerView.getViewRootImpl();
119        if (nativeDrawGLFunctor != 0 && viewRootImpl != null) {
120            viewRootImpl.detachFunctor(nativeDrawGLFunctor);
121        }
122    }
123
124    /**
125     * Returns the package id of the given {@code packageName}.
126     */
127    public int getPackageId(Resources resources, String packageName) {
128        SparseArray<String> packageIdentifiers =
129                resources.getAssets().getAssignedPackageIdentifiers();
130        for (int i = 0; i < packageIdentifiers.size(); i++) {
131            final String name = packageIdentifiers.valueAt(i);
132
133            if (packageName.equals(name)) {
134                return packageIdentifiers.keyAt(i);
135            }
136        }
137        throw new RuntimeException("Package not found: " + packageName);
138    }
139
140    /**
141     * Returns the application which is embedding the WebView.
142     */
143    public Application getApplication() {
144        return ActivityThread.currentApplication();
145    }
146
147    /**
148     * Returns the error string for the given {@code errorCode}.
149     */
150    public String getErrorString(Context context, int errorCode) {
151        return ErrorStrings.getString(errorCode, context);
152    }
153
154    /**
155     * Adds the WebView asset path to {@link AssetManager}.
156     */
157    public void addWebViewAssetPath(Context context) {
158        context.getAssets().addAssetPath(
159                WebViewFactory.getLoadedPackageInfo().applicationInfo.sourceDir);
160    }
161}
162