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.tools.layoutlib.annotations.LayoutlibDelegate;
20
21import org.xmlpull.v1.XmlPullParser;
22import org.xmlpull.v1.XmlPullParserException;
23
24import android.content.res.TypedArray;
25import android.content.res.XmlResourceParser;
26import android.util.AttributeSet;
27import android.util.Xml;
28
29import java.io.IOException;
30
31/**
32 * Delegate used to provide new implementation of a select few methods of {@link LayoutInflater}
33 *
34 * Through the layoutlib_create tool, the original  methods of LayoutInflater have been replaced
35 * by calls to methods of the same name in this delegate class.
36 *
37 */
38public class LayoutInflater_Delegate {
39
40    private static final String TAG_MERGE = "merge";
41
42    public static boolean sIsInInclude = false;
43
44    /**
45     * Recursive method used to descend down the xml hierarchy and instantiate
46     * views, instantiate their children, and then call onFinishInflate().
47     *
48     * This implementation just records the merge status before calling the default implementation.
49     */
50    @LayoutlibDelegate
51    /*package*/ static void rInflate(LayoutInflater thisInflater,
52            XmlPullParser parser, View parent, final AttributeSet attrs,
53            boolean finishInflate) throws XmlPullParserException, IOException {
54
55        if (finishInflate == false) {
56            // this is a merge rInflate!
57            if (thisInflater instanceof BridgeInflater) {
58                ((BridgeInflater) thisInflater).setIsInMerge(true);
59            }
60        }
61
62        // ---- START DEFAULT IMPLEMENTATION.
63
64        thisInflater.rInflate_Original(parser, parent, attrs, finishInflate);
65
66        // ---- END DEFAULT IMPLEMENTATION.
67
68        if (finishInflate == false) {
69            // this is a merge rInflate!
70            if (thisInflater instanceof BridgeInflater) {
71                ((BridgeInflater) thisInflater).setIsInMerge(false);
72            }
73        }
74    }
75
76    @LayoutlibDelegate
77    public static void parseInclude(
78            LayoutInflater thisInflater,
79            XmlPullParser parser, View parent, AttributeSet attrs)
80            throws XmlPullParserException, IOException {
81
82        int type;
83
84        if (parent instanceof ViewGroup) {
85            final int layout = attrs.getAttributeResourceValue(null, "layout", 0);
86            if (layout == 0) {
87                final String value = attrs.getAttributeValue(null, "layout");
88                if (value == null) {
89                    throw new InflateException("You must specifiy a layout in the"
90                            + " include tag: <include layout=\"@layout/layoutID\" />");
91                } else {
92                    throw new InflateException("You must specifiy a valid layout "
93                            + "reference. The layout ID " + value + " is not valid.");
94                }
95            } else {
96                final XmlResourceParser childParser =
97                    thisInflater.getContext().getResources().getLayout(layout);
98
99                try {
100                    final AttributeSet childAttrs = Xml.asAttributeSet(childParser);
101
102                    while ((type = childParser.next()) != XmlPullParser.START_TAG &&
103                            type != XmlPullParser.END_DOCUMENT) {
104                        // Empty.
105                    }
106
107                    if (type != XmlPullParser.START_TAG) {
108                        throw new InflateException(childParser.getPositionDescription() +
109                                ": No start tag found!");
110                    }
111
112                    final String childName = childParser.getName();
113
114                    if (TAG_MERGE.equals(childName)) {
115                        // Inflate all children.
116                        thisInflater.rInflate(childParser, parent, childAttrs, false);
117                    } else {
118                        final View view = thisInflater.createViewFromTag(parent, childName, childAttrs);
119                        final ViewGroup group = (ViewGroup) parent;
120
121                        // We try to load the layout params set in the <include /> tag. If
122                        // they don't exist, we will rely on the layout params set in the
123                        // included XML file.
124                        // During a layoutparams generation, a runtime exception is thrown
125                        // if either layout_width or layout_height is missing. We catch
126                        // this exception and set localParams accordingly: true means we
127                        // successfully loaded layout params from the <include /> tag,
128                        // false means we need to rely on the included layout params.
129                        ViewGroup.LayoutParams params = null;
130                        try {
131                            // ---- START CHANGES
132                            sIsInInclude = true;
133                            // ---- END CHANGES
134
135                            params = group.generateLayoutParams(attrs);
136
137                        } catch (RuntimeException e) {
138                            // ---- START CHANGES
139                            sIsInInclude = false;
140                            // ---- END CHANGES
141
142                            params = group.generateLayoutParams(childAttrs);
143                        } finally {
144                            // ---- START CHANGES
145                            sIsInInclude = false;
146                            // ---- END CHANGES
147
148                            if (params != null) {
149                                view.setLayoutParams(params);
150                            }
151                        }
152
153                        // Inflate all children.
154                        thisInflater.rInflate(childParser, view, childAttrs, true);
155
156                        // Attempt to override the included layout's android:id with the
157                        // one set on the <include /> tag itself.
158                        TypedArray a = thisInflater.mContext.obtainStyledAttributes(attrs,
159                            com.android.internal.R.styleable.View, 0, 0);
160                        int id = a.getResourceId(com.android.internal.R.styleable.View_id, View.NO_ID);
161                        // While we're at it, let's try to override android:visibility.
162                        int visibility = a.getInt(com.android.internal.R.styleable.View_visibility, -1);
163                        a.recycle();
164
165                        if (id != View.NO_ID) {
166                            view.setId(id);
167                        }
168
169                        switch (visibility) {
170                            case 0:
171                                view.setVisibility(View.VISIBLE);
172                                break;
173                            case 1:
174                                view.setVisibility(View.INVISIBLE);
175                                break;
176                            case 2:
177                                view.setVisibility(View.GONE);
178                                break;
179                        }
180
181                        group.addView(view);
182                    }
183                } finally {
184                    childParser.close();
185                }
186            }
187        } else {
188            throw new InflateException("<include /> can only be used inside of a ViewGroup");
189        }
190
191        final int currentDepth = parser.getDepth();
192        while (((type = parser.next()) != XmlPullParser.END_TAG ||
193                parser.getDepth() > currentDepth) && type != XmlPullParser.END_DOCUMENT) {
194            // Empty
195        }
196    }
197
198
199}
200