HTMLViewerActivity.java revision 931fd3728855b03bcab825ce10475d7447e9097a 
1/*
2 * Copyright (C) 2008 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.htmlviewer;
18
19import android.app.Activity;
20import android.content.Intent;
21import android.net.Uri;
22import android.os.Bundle;
23import android.util.Log;
24import android.view.Window;
25import android.webkit.CookieSyncManager;
26import android.webkit.WebChromeClient;
27import android.webkit.WebSettings;
28import android.webkit.WebView;
29
30import java.io.File;
31import java.io.FileInputStream;
32import java.io.FileNotFoundException;
33import java.io.IOException;
34import java.io.InputStream;
35
36/**
37 * Wraps a WebView widget within an Activity. When launched, it uses the
38 * URI from the intent as the URL to load into the WebView.
39 * It supports all URLs schemes that a standard WebView supports, as well as
40 * loading the top level markup using the file scheme.
41 * The WebView default settings are used with the exception of normal layout
42 * is set.
43 * This activity shows a loading progress bar in the window title and sets
44 * the window title to the title of the content.
45 *
46 */
47public class HTMLViewerActivity extends Activity {
48
49    /*
50     * The WebView that is placed in this Activity
51     */
52    private WebView mWebView;
53
54    /*
55     * As the file content is loaded completely into RAM first, set
56     * a limitation on the file size so we don't use too much RAM. If someone
57     * wants to load content that is larger than this, then a content
58     * provider should be used.
59     */
60    static final int MAXFILESIZE = 8096;
61
62    static final String LOGTAG = "HTMLViewerActivity";
63
64    @Override
65    protected void onCreate(Bundle savedInstanceState) {
66        super.onCreate(savedInstanceState);
67
68        // Call createInstance() explicitly. createInstance() is called in
69        // BrowserFrame by WebView. As it is called in WebCore thread, it can
70        // happen after onResume() is called. To use getInstance() in onResume,
71        // createInstance() needs to be called first.
72        CookieSyncManager.createInstance(this);
73
74        requestWindowFeature(Window.FEATURE_PROGRESS);
75
76        mWebView = new WebView(this);
77        setContentView(mWebView);
78
79        // Setup callback support for title and progress bar
80        mWebView.setWebChromeClient( new WebChrome() );
81
82        // Configure the webview
83        WebSettings s = mWebView.getSettings();
84        s.setLayoutAlgorithm(WebSettings.LayoutAlgorithm.NARROW_COLUMNS);
85        s.setUseWideViewPort(true);
86        s.setSavePassword(false);
87        s.setSaveFormData(false);
88        s.setBlockNetworkLoads(true);
89
90        // Javascript is purposely disabled, so that nothing can be
91        // automatically run.
92        s.setJavaScriptEnabled(false);
93
94        // Restore a webview if we are meant to restore
95        if (savedInstanceState != null) {
96            mWebView.restoreState(savedInstanceState);
97        } else {
98            // Check the intent for the content to view
99            Intent intent = getIntent();
100            if (intent.getData() != null) {
101                Uri uri = intent.getData();
102                if ("file".equals(uri.getScheme())) {
103                    String contentUri =
104                        FileContentProvider.BASE_URI +
105                        uri.getEncodedPath() +
106                        "?" +
107                        intent.getType();
108                    mWebView.loadUrl(contentUri);
109                } else {
110                    mWebView.loadUrl(intent.getData().toString() +
111                        "?" + intent.getType());
112                }
113            }
114        }
115    }
116
117    @Override
118    protected void onResume() {
119        super.onResume();
120        CookieSyncManager.getInstance().startSync();
121    }
122
123    @Override
124    protected void onSaveInstanceState(Bundle outState) {
125        // the default implementation requires each view to have an id. As the
126        // browser handles the state itself and it doesn't use id for the views,
127        // don't call the default implementation. Otherwise it will trigger the
128        // warning like this, "couldn't save which view has focus because the
129        // focused view XXX has no id".
130        mWebView.saveState(outState);
131    }
132
133    @Override
134    protected void onStop() {
135        super.onStop();
136
137        CookieSyncManager.getInstance().stopSync();
138        mWebView.stopLoading();
139    }
140
141    @Override
142    protected void onDestroy() {
143        super.onDestroy();
144        mWebView.destroy();
145    }
146
147    class WebChrome extends WebChromeClient {
148
149        @Override
150        public void onReceivedTitle(WebView view, String title) {
151            HTMLViewerActivity.this.setTitle(title);
152        }
153
154        @Override
155        public void onProgressChanged(WebView view, int newProgress) {
156            getWindow().setFeatureInt(
157                    Window.FEATURE_PROGRESS, newProgress*100);
158            if (newProgress == 100) {
159                CookieSyncManager.getInstance().sync();
160            }
161        }
162    }
163
164}
165