forked from xamarin/Xamarin.Forms
-
Notifications
You must be signed in to change notification settings - Fork 0
/
XamlParser.cs
503 lines (446 loc) · 16.3 KB
/
XamlParser.cs
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
//
// XamlParser.cs
//
// Author:
// Stephane Delcroix <stephane@mi8.be>
//
// Copyright (c) 2013 Mobile Inception
// Copyright (c) 2013-2014 Xamarin, Inc
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Reflection;
using System.Xml;
using Xamarin.Forms.Internals;
namespace Xamarin.Forms.Xaml
{
static class XamlParser
{
public const string XFUri = "http://xamarin.com/schemas/2014/forms";
public const string XFDesignUri = "http://xamarin.com/schemas/2014/forms/design";
public const string X2006Uri = "http://schemas.microsoft.com/winfx/2006/xaml";
public const string X2009Uri = "http://schemas.microsoft.com/winfx/2009/xaml";
public const string McUri = "http://schemas.openxmlformats.org/markup-compatibility/2006";
public static void ParseXaml(RootNode rootNode, XmlReader reader)
{
var attributes = ParseXamlAttributes(reader, out IList<KeyValuePair<string, string>> xmlns);
var prefixes = PrefixesToIgnore(xmlns);
(rootNode.IgnorablePrefixes ?? (rootNode.IgnorablePrefixes = new List<string>())).AddRange(prefixes);
rootNode.Properties.AddRange(attributes);
ParseXamlElementFor(rootNode, reader);
}
static void ParseXamlElementFor(IElementNode node, XmlReader reader)
{
Debug.Assert(reader.NodeType == XmlNodeType.Element);
var elementName = reader.Name;
var isEmpty = reader.IsEmptyElement;
if (isEmpty)
return;
while (reader.Read())
{
switch (reader.NodeType)
{
case XmlNodeType.EndElement:
Debug.Assert(reader.Name == elementName); //make sure we close the right element
return;
case XmlNodeType.Element:
// 1. Property Element.
if (reader.Name.Contains("."))
{
XmlName name;
if (reader.Name.StartsWith(elementName + ".", StringComparison.Ordinal))
name = new XmlName(reader.NamespaceURI, reader.Name.Substring(elementName.Length + 1));
else //Attached BP
name = new XmlName(reader.NamespaceURI, reader.LocalName);
if (node.Properties.ContainsKey(name))
throw new XamlParseException($"'{reader.Name}' is a duplicate property name.", (IXmlLineInfo)reader);
INode prop = null;
if (reader.IsEmptyElement)
Debug.WriteLine($"Unexpected empty element '<{reader.Name} />'", (IXmlLineInfo)reader);
else
prop = ReadNode(reader);
if (prop != null)
node.Properties.Add(name, prop);
}
// 2. Xaml2009 primitives, x:Arguments, ...
else if (reader.NamespaceURI == X2009Uri && reader.LocalName == "Arguments")
{
if (node.Properties.ContainsKey(XmlName.xArguments))
throw new XamlParseException($"'x:Arguments' is a duplicate directive name.", (IXmlLineInfo)reader);
var prop = ReadNode(reader);
if (prop != null)
node.Properties.Add(XmlName.xArguments, prop);
}
// 3. DataTemplate (should be handled by 4.)
else if (node.XmlType.NamespaceUri == XFUri &&
(node.XmlType.Name == "DataTemplate" || node.XmlType.Name == "ControlTemplate"))
{
if (node.Properties.ContainsKey(XmlName._CreateContent))
throw new XamlParseException($"Multiple child elements in {node.XmlType.Name}", (IXmlLineInfo)reader);
var prop = ReadNode(reader, true);
if (prop != null)
node.Properties.Add(XmlName._CreateContent, prop);
}
// 4. Implicit content, implicit collection, or collection syntax. Add to CollectionItems, resolve case later.
else
{
var item = ReadNode(reader, true);
if (item != null)
node.CollectionItems.Add(item);
}
break;
case XmlNodeType.Whitespace:
break;
case XmlNodeType.Text:
case XmlNodeType.CDATA:
if (node.CollectionItems.Count == 1 && node.CollectionItems[0] is ValueNode)
((ValueNode)node.CollectionItems[0]).Value += reader.Value.Trim();
else
node.CollectionItems.Add(new ValueNode(reader.Value.Trim(), (IXmlNamespaceResolver)reader));
break;
default:
Debug.WriteLine("Unhandled node {0} {1} {2}", reader.NodeType, reader.Name, reader.Value);
break;
}
}
}
static INode ReadNode(XmlReader reader, bool nested = false)
{
var skipFirstRead = nested;
Debug.Assert(reader.NodeType == XmlNodeType.Element);
var name = reader.Name;
var nodes = new List<INode>();
while (skipFirstRead || reader.Read())
{
skipFirstRead = false;
INode node;
switch (reader.NodeType)
{
case XmlNodeType.EndElement:
Debug.Assert(reader.Name == name);
if (nodes.Count == 0) //Empty element
return null;
if (nodes.Count == 1)
return nodes[0];
return new ListNode(nodes, (IXmlNamespaceResolver)reader, ((IXmlLineInfo)reader).LineNumber,
((IXmlLineInfo)reader).LinePosition);
case XmlNodeType.Element:
var isEmpty = reader.IsEmptyElement && reader.Name == name;
var elementName = reader.Name;
var elementNsUri = reader.NamespaceURI;
var elementXmlInfo = (IXmlLineInfo)reader;
IList<KeyValuePair<string, string>> xmlns;
var attributes = ParseXamlAttributes(reader, out xmlns);
var prefixes = PrefixesToIgnore(xmlns);
var typeArguments = GetTypeArguments(attributes);
node = new ElementNode(new XmlType(elementNsUri, elementName, typeArguments), elementNsUri,
reader as IXmlNamespaceResolver, elementXmlInfo.LineNumber, elementXmlInfo.LinePosition);
((IElementNode)node).Properties.AddRange(attributes);
(node.IgnorablePrefixes ?? (node.IgnorablePrefixes = new List<string>())).AddRange(prefixes);
ParseXamlElementFor((IElementNode)node, reader);
nodes.Add(node);
if (isEmpty || nested)
return node;
break;
case XmlNodeType.Text:
case XmlNodeType.CDATA:
node = new ValueNode(reader.Value.Trim(), (IXmlNamespaceResolver)reader, ((IXmlLineInfo)reader).LineNumber,
((IXmlLineInfo)reader).LinePosition);
nodes.Add(node);
break;
case XmlNodeType.Whitespace:
break;
default:
Debug.WriteLine("Unhandled node {0} {1} {2}", reader.NodeType, reader.Name, reader.Value);
break;
}
}
throw new XamlParseException("Closing PropertyElement expected", (IXmlLineInfo)reader);
}
internal static IList<XmlType> GetTypeArguments(XmlReader reader) => GetTypeArguments(ParseXamlAttributes(reader, out _));
static IList<XmlType> GetTypeArguments(IList<KeyValuePair<XmlName, INode>> attributes)
{
return attributes.Any(kvp => kvp.Key == XmlName.xTypeArguments)
? ((ValueNode)attributes.First(kvp => kvp.Key == XmlName.xTypeArguments).Value).Value as IList<XmlType>
: null;
}
static IList<KeyValuePair<XmlName, INode>> ParseXamlAttributes(XmlReader reader, out IList<KeyValuePair<string, string>> xmlns)
{
Debug.Assert(reader.NodeType == XmlNodeType.Element);
var attributes = new List<KeyValuePair<XmlName, INode>>();
xmlns = new List<KeyValuePair<string, string>>();
for (var i = 0; i < reader.AttributeCount; i++)
{
reader.MoveToAttribute(i);
//skip xmlns
if (reader.NamespaceURI == "http://www.w3.org/2000/xmlns/")
{
xmlns.Add(new KeyValuePair<string, string>(reader.LocalName, reader.Value));
continue;
}
var namespaceUri = reader.NamespaceURI;
if (reader.LocalName.Contains(".") && namespaceUri == "")
namespaceUri = ((IXmlNamespaceResolver)reader).LookupNamespace("");
var propertyName = ParsePropertyName(new XmlName(namespaceUri, reader.LocalName));
if (propertyName.NamespaceURI == null && propertyName.LocalName == null)
continue;
object value = reader.Value;
if (propertyName == XmlName.xTypeArguments)
value = TypeArgumentsParser.ParseExpression((string)value, (IXmlNamespaceResolver)reader, (IXmlLineInfo)reader);
var propertyNode = GetValueNode(value, reader);
attributes.Add(new KeyValuePair<XmlName, INode>(propertyName, propertyNode));
}
reader.MoveToElement();
return attributes;
}
public static XmlName ParsePropertyName(XmlName name)
{
if (name.NamespaceURI == X2006Uri)
{
switch (name.LocalName)
{
case "Key":
return XmlName.xKey;
case "Name":
return XmlName.xName;
case "Class":
case "FieldModifier":
return new XmlName(null, null);
default:
Debug.WriteLine("Unhandled attribute {0}", name);
return new XmlName(null, null);
}
}
if (name.NamespaceURI == X2009Uri)
{
switch (name.LocalName)
{
case "Key":
return XmlName.xKey;
case "Name":
return XmlName.xName;
case "TypeArguments":
return XmlName.xTypeArguments;
case "DataType":
return XmlName.xDataType;
case "Class":
case "FieldModifier":
return new XmlName(null, null);
case "FactoryMethod":
return XmlName.xFactoryMethod;
case "Arguments":
return XmlName.xArguments;
default:
Debug.WriteLine("Unhandled attribute {0}", name);
return new XmlName(null, null);
}
}
return name;
}
static IList<string> PrefixesToIgnore(IList<KeyValuePair<string, string>> xmlns)
{
var prefixes = new List<string>();
foreach (var kvp in xmlns)
{
var prefix = kvp.Key;
string typeName = null, ns = null, asm = null, targetPlatform = null;
XmlnsHelper.ParseXmlns(kvp.Value, out typeName, out ns, out asm, out targetPlatform);
if (targetPlatform == null)
continue;
try
{
if (targetPlatform != Device.RuntimePlatform)
{
// Special case for Windows backward compatibility
if (targetPlatform == "Windows" && Device.RuntimePlatform == Device.UWP)
continue;
prefixes.Add(prefix);
}
}
catch (InvalidOperationException)
{
prefixes.Add(prefix);
}
}
return prefixes;
}
static IValueNode GetValueNode(object value, XmlReader reader)
{
var valueString = value as string;
if (valueString != null && valueString.Trim().StartsWith("{}", StringComparison.Ordinal))
{
return new ValueNode(valueString.Substring(2), (IXmlNamespaceResolver)reader, ((IXmlLineInfo)reader).LineNumber,
((IXmlLineInfo)reader).LinePosition);
}
if (valueString != null && valueString.Trim().StartsWith("{", StringComparison.Ordinal))
{
return new MarkupNode(valueString.Trim(), reader as IXmlNamespaceResolver, ((IXmlLineInfo)reader).LineNumber,
((IXmlLineInfo)reader).LinePosition);
}
return new ValueNode(value, (IXmlNamespaceResolver)reader, ((IXmlLineInfo)reader).LineNumber,
((IXmlLineInfo)reader).LinePosition);
}
static IList<XmlnsDefinitionAttribute> s_xmlnsDefinitions;
static void GatherXmlnsDefinitionAttributes()
{
Assembly[] assemblies = null;
#if !NETSTANDARD2_0
assemblies = new[] {
typeof(XamlLoader).GetTypeInfo().Assembly,
typeof(View).GetTypeInfo().Assembly,
};
#else
assemblies = AppDomain.CurrentDomain.GetAssemblies();
#endif
s_xmlnsDefinitions = new List<XmlnsDefinitionAttribute>();
foreach (var assembly in assemblies)
foreach (XmlnsDefinitionAttribute attribute in assembly.GetCustomAttributes(typeof(XmlnsDefinitionAttribute)))
{
s_xmlnsDefinitions.Add(attribute);
attribute.AssemblyName = attribute.AssemblyName ?? assembly.FullName;
}
}
public static Type GetElementType(XmlType xmlType, IXmlLineInfo xmlInfo, Assembly currentAssembly,
out XamlParseException exception)
{
#if NETSTANDARD2_0
bool hasRetriedNsSearch = false;
#endif
IList<XamlLoader.FallbackTypeInfo> potentialTypes;
#if NETSTANDARD2_0
retry:
#endif
if (s_xmlnsDefinitions == null)
GatherXmlnsDefinitionAttributes();
Type type = xmlType.GetTypeReference(
s_xmlnsDefinitions,
currentAssembly?.FullName,
(typeInfo) =>
Type.GetType($"{typeInfo.ClrNamespace}.{typeInfo.TypeName}, {typeInfo.AssemblyName}"),
out potentialTypes);
var typeArguments = xmlType.TypeArguments;
exception = null;
#if NETSTANDARD2_0
if (type == null)
{
// This covers the scenario where the AppDomain's loaded
// assemblies might have changed since this method was first
// called. This occurred during unit test runs and could
// conceivably occur in the field.
if (!hasRetriedNsSearch)
{
hasRetriedNsSearch = true;
s_xmlnsDefinitions = null;
goto retry;
}
}
#endif
if (XamlLoader.FallbackTypeResolver != null)
type = XamlLoader.FallbackTypeResolver(potentialTypes, type);
if (type != null && typeArguments != null)
{
XamlParseException innerexception = null;
var args = typeArguments.Select(delegate (XmlType xmltype)
{
var t = GetElementType(xmltype, xmlInfo, currentAssembly, out XamlParseException xpe);
if (xpe != null)
{
innerexception = xpe;
return null;
}
return t;
}).ToArray();
if (innerexception != null)
{
exception = innerexception;
return null;
}
try
{
type = type.MakeGenericType(args);
}
catch (InvalidOperationException)
{
exception = new XamlParseException($"Type {type} is not a GenericTypeDefinition", xmlInfo);
}
}
if (type == null)
exception = new XamlParseException($"Type {xmlType.Name} not found in xmlns {xmlType.NamespaceUri}", xmlInfo);
return type;
}
public static T GetTypeReference<T>(
this XmlType xmlType,
IEnumerable<XmlnsDefinitionAttribute> xmlnsDefinitions,
string defaultAssemblyName,
Func<XamlLoader.FallbackTypeInfo, T> refFromTypeInfo,
out IList<XamlLoader.FallbackTypeInfo> potentialTypes)
where T : class
{
var lookupAssemblies = new List<XmlnsDefinitionAttribute>();
var namespaceURI = xmlType.NamespaceUri;
var elementName = xmlType.Name;
var typeArguments = xmlType.TypeArguments;
potentialTypes = null;
foreach (var xmlnsDef in xmlnsDefinitions)
{
if (xmlnsDef.XmlNamespace != namespaceURI)
continue;
lookupAssemblies.Add(xmlnsDef);
}
if (lookupAssemblies.Count == 0)
{
XmlnsHelper.ParseXmlns(namespaceURI, out _, out var ns, out var asmstring, out _);
asmstring = asmstring ?? defaultAssemblyName;
if (namespaceURI != null && ns != null)
lookupAssemblies.Add(new XmlnsDefinitionAttribute(namespaceURI, ns) { AssemblyName = asmstring });
}
var lookupNames = new List<string>();
if (elementName != "DataTemplate" && !elementName.EndsWith("Extension", StringComparison.Ordinal))
lookupNames.Add(elementName + "Extension");
lookupNames.Add(elementName);
for (var i = 0; i < lookupNames.Count; i++)
{
var name = lookupNames[i];
if (name.Contains(":"))
name = name.Substring(name.LastIndexOf(':') + 1);
if (typeArguments != null)
name += "`" + typeArguments.Count; //this will return an open generic Type
lookupNames[i] = name;
}
potentialTypes = new List<XamlLoader.FallbackTypeInfo>();
foreach (string typeName in lookupNames)
foreach (XmlnsDefinitionAttribute xmlnsDefinitionAttribute in lookupAssemblies)
potentialTypes.Add(new XamlLoader.FallbackTypeInfo
{
ClrNamespace = xmlnsDefinitionAttribute.ClrNamespace,
TypeName = typeName,
AssemblyName = xmlnsDefinitionAttribute.AssemblyName,
XmlNamespace = xmlnsDefinitionAttribute.XmlNamespace
});
T type = null;
foreach (XamlLoader.FallbackTypeInfo typeInfo in potentialTypes)
if ((type = refFromTypeInfo(typeInfo)) != null)
break;
return type;
}
}
}