WebViewPreview.java revision 8fc22a1c7846b4c7c7b74d1ec59ffc59c2695c15 
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.browser.preferences;
18
19import com.android.browser.BrowserSettings;
20import com.android.browser.R;
21
22import android.content.Context;
23import android.content.SharedPreferences;
24import android.content.SharedPreferences.OnSharedPreferenceChangeListener;
25import android.content.res.Resources;
26import android.preference.Preference;
27import android.preference.PreferenceManager;
28import android.util.AttributeSet;
29import android.view.View;
30import android.view.ViewGroup;
31import android.webkit.WebSettings;
32import android.webkit.WebView;
33
34public class WebViewPreview extends Preference implements OnSharedPreferenceChangeListener {
35
36    static final String HTML_FORMAT = "<html><head><style type=\"text/css\">p { margin: 2px auto;}</style><body><p style=\"font-size: .4em\">%s</p><p style=\"font-size: .7em\">%s</p><p style=\"font-size: 1em\">%s</p><p style=\"font-size: 1.3em\">%s</p><p style=\"font-size: 1.6em\">%s</p></body></html>";
37
38    String mHtml;
39    private WebView mWebView;
40
41    public WebViewPreview(
42            Context context, AttributeSet attrs, int defStyle) {
43        super(context, attrs, defStyle);
44        init(context);
45    }
46
47    public WebViewPreview(Context context, AttributeSet attrs) {
48        super(context, attrs);
49        init(context);
50    }
51
52    public WebViewPreview(Context context) {
53        super(context);
54        init(context);
55    }
56
57    void init(Context context) {
58        Resources res = context.getResources();
59        Object[] visualNames = res.getStringArray(R.array.pref_text_size_choices);
60        mHtml = String.format(HTML_FORMAT, visualNames);
61        setLayoutResource(R.layout.webview_preview);
62    }
63
64    void updatePreview() {
65        if (mWebView == null) return;
66
67        WebSettings ws = mWebView.getSettings();
68        BrowserSettings bs = BrowserSettings.getInstance();
69        ws.setMinimumFontSize(bs.getMinimumFontSize());
70        ws.setTextSize(bs.getTextSize());
71        mWebView.loadData(mHtml, "text/html", "utf-8");
72    }
73
74    @Override
75    protected View onCreateView(ViewGroup parent) {
76        View root = super.onCreateView(parent);
77        WebView webView = (WebView) root.findViewById(R.id.webview);
78        webView.setFocusable(false);
79        webView.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
80        return root;
81    }
82
83    @Override
84    protected void onBindView(View view) {
85        super.onBindView(view);
86        mWebView = (WebView) view.findViewById(R.id.webview);
87        updatePreview();
88    }
89
90    @Override
91    protected void onAttachedToHierarchy(PreferenceManager preferenceManager) {
92        super.onAttachedToHierarchy(preferenceManager);
93        getSharedPreferences().registerOnSharedPreferenceChangeListener(this);
94    }
95
96    @Override
97    protected void onPrepareForRemoval() {
98        getSharedPreferences().unregisterOnSharedPreferenceChangeListener(this);
99        super.onPrepareForRemoval();
100    }
101
102    @Override
103    public void onSharedPreferenceChanged(
104            SharedPreferences sharedPreferences, String key) {
105        updatePreview();
106    }
107
108}
109