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 android.view;
18
19import com.android.layoutlib.bridge.android.BridgeInflater;
20import com.android.tools.layoutlib.annotations.LayoutlibDelegate;
21
22import org.xmlpull.v1.XmlPullParser;
23import org.xmlpull.v1.XmlPullParserException;
24
25import android.content.res.TypedArray;
26import android.content.res.XmlResourceParser;
27import android.util.AttributeSet;
28import android.util.Xml;
29
30import java.io.IOException;
31
32/**
33 * Delegate used to provide new implementation of a select few methods of {@link LayoutInflater}
34 *
35 * Through the layoutlib_create tool, the original  methods of LayoutInflater have been replaced
36 * by calls to methods of the same name in this delegate class.
37 *
38 * Generally we don't want to copy-paste a huge method like that just for one small features,
39 * but because this is done after this platform is final and the next version (Honeycomb) has a
40 * better mechanism (or slightly less copy-paste), maintenance of this duplicated code is not
41 * a problem.
42 *
43 */
44public class LayoutInflater_Delegate {
45
46    public static boolean sIsInInclude = false;
47
48    @LayoutlibDelegate
49    /*package*/ static void parseInclude(LayoutInflater thisInflater,
50            XmlPullParser parser, View parent, AttributeSet attrs)
51            throws XmlPullParserException, IOException {
52
53        int type;
54
55        if (parent instanceof ViewGroup) {
56            final int layout = attrs.getAttributeResourceValue(null, "layout", 0);
57            if (layout == 0) {
58                final String value = attrs.getAttributeValue(null, "layout");
59                if (value == null) {
60                    throw new InflateException("You must specifiy a layout in the"
61                            + " include tag: <include layout=\"@layout/layoutID\" />");
62                } else {
63                    throw new InflateException("You must specifiy a valid layout "
64                            + "reference. The layout ID " + value + " is not valid.");
65                }
66            } else {
67                final XmlResourceParser childParser =
68                    thisInflater.getContext().getResources().getLayout(layout);
69
70                try {
71                    final AttributeSet childAttrs = Xml.asAttributeSet(childParser);
72
73                    while ((type = childParser.next()) != XmlPullParser.START_TAG &&
74                            type != XmlPullParser.END_DOCUMENT) {
75                        // Empty.
76                    }
77
78                    if (type != XmlPullParser.START_TAG) {
79                        throw new InflateException(childParser.getPositionDescription() +
80                                ": No start tag found!");
81                    }
82
83                    final String childName = childParser.getName();
84
85                    if (LayoutInflater.TAG_MERGE.equals(childName)) {
86                        // ---- START MODIFICATIONS ----
87                        if (thisInflater instanceof BridgeInflater) {
88                            ((BridgeInflater) thisInflater).setIsInMerge(true);
89                        }
90                        // ---- END MODIFICATIONS ----
91
92                        // Inflate all children.
93                        thisInflater.rInflate(childParser, parent, childAttrs);
94
95                        // ---- START MODIFICATIONS ----
96                        if (thisInflater instanceof BridgeInflater) {
97                            ((BridgeInflater) thisInflater).setIsInMerge(false);
98                        }
99                        // ---- END MODIFICATIONS ----
100                    } else {
101                        final View view = thisInflater.createViewFromTag(childName, childAttrs);
102                        final ViewGroup group = (ViewGroup) parent;
103
104                        // We try to load the layout params set in the <include /> tag. If
105                        // they don't exist, we will rely on the layout params set in the
106                        // included XML file.
107                        // During a layoutparams generation, a runtime exception is thrown
108                        // if either layout_width or layout_height is missing. We catch
109                        // this exception and set localParams accordingly: true means we
110                        // successfully loaded layout params from the <include /> tag,
111                        // false means we need to rely on the included layout params.
112                        ViewGroup.LayoutParams params = null;
113                        try {
114                            // ---- START CHANGES
115                            sIsInInclude = true;
116                            // ---- END CHANGES
117
118                            params = group.generateLayoutParams(attrs);
119                        } catch (RuntimeException e) {
120                            // ---- START CHANGES
121                            sIsInInclude = false;
122                            // ---- END CHANGES
123
124                            params = group.generateLayoutParams(childAttrs);
125                        } finally {
126                            // ---- START CHANGES
127                            sIsInInclude = false;
128                            // ---- END CHANGES
129
130                            if (params != null) {
131                                view.setLayoutParams(params);
132                            }
133                        }
134
135                        // Inflate all children.
136                        thisInflater.rInflate(childParser, view, childAttrs);
137
138                        // Attempt to override the included layout's android:id with the
139                        // one set on the <include /> tag itself.
140                        TypedArray a = thisInflater.mContext.obtainStyledAttributes(attrs,
141                            com.android.internal.R.styleable.View, 0, 0);
142                        int id = a.getResourceId(com.android.internal.R.styleable.View_id, View.NO_ID);
143                        // While we're at it, let's try to override android:visibility.
144                        int visibility = a.getInt(com.android.internal.R.styleable.View_visibility, -1);
145                        a.recycle();
146
147                        if (id != View.NO_ID) {
148                            view.setId(id);
149                        }
150
151                        switch (visibility) {
152                            case 0:
153                                view.setVisibility(View.VISIBLE);
154                                break;
155                            case 1:
156                                view.setVisibility(View.INVISIBLE);
157                                break;
158                            case 2:
159                                view.setVisibility(View.GONE);
160                                break;
161                        }
162
163                        group.addView(view);
164                    }
165                } finally {
166                    childParser.close();
167                }
168            }
169        } else {
170            throw new InflateException("<include /> can only be used inside of a ViewGroup");
171        }
172
173        final int currentDepth = parser.getDepth();
174        while (((type = parser.next()) != XmlPullParser.END_TAG ||
175                parser.getDepth() > currentDepth) && type != XmlPullParser.END_DOCUMENT) {
176            // Empty
177        }
178    }
179}
180