1/*
2 * Copyright (C) 2010 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.camera;
18
19import org.xmlpull.v1.XmlPullParser;
20import org.xmlpull.v1.XmlPullParserException;
21
22import java.io.IOException;
23import java.lang.reflect.Constructor;
24import java.util.ArrayList;
25import java.util.HashMap;
26
27import android.content.Context;
28import android.util.AttributeSet;
29import android.util.Xml;
30import android.view.InflateException;
31
32/**
33 * Inflate <code>CameraPreference</code> from XML resource.
34 */
35public class PreferenceInflater {
36    private static final String PACKAGE_NAME =
37            PreferenceInflater.class.getPackage().getName();
38
39    private static final Class<?>[] CTOR_SIGNATURE =
40            new Class[] {Context.class, AttributeSet.class};
41    private static final HashMap<String, Constructor<?>> sConstructorMap =
42            new HashMap<String, Constructor<?>>();
43
44    private Context mContext;
45
46    public PreferenceInflater(Context context) {
47        mContext = context;
48    }
49
50    public CameraPreference inflate(int resId) {
51        return inflate(mContext.getResources().getXml(resId));
52    }
53
54    private CameraPreference newPreference(String tagName, Object[] args) {
55        String name = PACKAGE_NAME + "." + tagName;
56        Constructor<?> constructor = sConstructorMap.get(name);
57        try {
58            if (constructor == null) {
59                // Class not found in the cache, see if it's real, and try to
60                // add it
61                Class<?> clazz = mContext.getClassLoader().loadClass(name);
62                constructor = clazz.getConstructor(CTOR_SIGNATURE);
63                sConstructorMap.put(name, constructor);
64            }
65            return (CameraPreference) constructor.newInstance(args);
66        } catch (NoSuchMethodException e) {
67            throw new InflateException("Error inflating class " + name, e);
68        } catch (ClassNotFoundException e) {
69            throw new InflateException("No such class: " + name, e);
70        } catch (Exception e) {
71            throw new InflateException("While create instance of" + name, e);
72        }
73    }
74
75    private CameraPreference inflate(XmlPullParser parser) {
76
77        AttributeSet attrs = Xml.asAttributeSet(parser);
78        ArrayList<CameraPreference> list = new ArrayList<CameraPreference>();
79        Object args[] = new Object[]{mContext, attrs};
80
81        try {
82            for (int type = parser.next();
83                    type != XmlPullParser.END_DOCUMENT; type = parser.next()) {
84                if (type != XmlPullParser.START_TAG) continue;
85                CameraPreference pref = newPreference(parser.getName(), args);
86
87                int depth = parser.getDepth();
88                if (depth > list.size()) {
89                    list.add(pref);
90                } else {
91                    list.set(depth - 1, pref);
92                }
93                if (depth > 1) {
94                    ((PreferenceGroup) list.get(depth - 2)).addChild(pref);
95                }
96            }
97
98            if (list.size() == 0) {
99                throw new InflateException("No root element found");
100            }
101            return list.get(0);
102        } catch (XmlPullParserException e) {
103            throw new InflateException(e);
104        } catch (IOException e) {
105            throw new InflateException(parser.getPositionDescription(), e);
106        }
107    }
108}
109