diff options
Diffstat (limited to 'Xamarin.Forms.Xaml/ExpandMarkupsVisitor.cs')
| -rw-r--r-- | Xamarin.Forms.Xaml/ExpandMarkupsVisitor.cs | 187 |
1 files changed, 187 insertions, 0 deletions
diff --git a/Xamarin.Forms.Xaml/ExpandMarkupsVisitor.cs b/Xamarin.Forms.Xaml/ExpandMarkupsVisitor.cs new file mode 100644 index 00000000..0d5e9ee6 --- /dev/null +++ b/Xamarin.Forms.Xaml/ExpandMarkupsVisitor.cs @@ -0,0 +1,187 @@ +using System; +using System.Collections.Generic; +using System.Xml; +using Xamarin.Forms.Xaml.Internals; + +namespace Xamarin.Forms.Xaml +{ + internal class ExpandMarkupsVisitor : IXamlNodeVisitor + { + public ExpandMarkupsVisitor(HydratationContext context) + { + Context = context; + } + + Dictionary<INode, object> Values + { + get { return Context.Values; } + } + + HydratationContext Context { get; } + + public bool VisitChildrenFirst + { + get { return true; } + } + + public bool StopOnDataTemplate + { + get { return false; } + } + + public bool StopOnResourceDictionary + { + get { return false; } + } + + public void Visit(ValueNode node, INode parentNode) + { + } + + public void Visit(MarkupNode markupnode, INode parentNode) + { + var parentElement = parentNode as IElementNode; + XmlName propertyName; + if (!ApplyPropertiesVisitor.TryGetPropertyName(markupnode, parentNode, out propertyName)) + return; + if (ApplyPropertiesVisitor.Skips.Contains(propertyName)) + return; + if (parentElement.SkipProperties.Contains(propertyName)) + return; + + var markupString = markupnode.MarkupString; + var node = + ParseExpression(ref markupString, markupnode.NamespaceResolver, markupnode, markupnode, parentNode) as IElementNode; + if (node != null) + { + ((IElementNode)parentNode).Properties[propertyName] = node; + node.Parent = parentNode; + } + } + + public void Visit(ElementNode node, INode parentNode) + { + } + + public void Visit(RootNode node, INode parentNode) + { + } + + public void Visit(ListNode node, INode parentNode) + { + } + + INode ParseExpression(ref string expression, IXmlNamespaceResolver nsResolver, IXmlLineInfo xmlLineInfo, INode node, + INode parentNode) + { + if (expression.StartsWith("{}", StringComparison.Ordinal)) + return new ValueNode(expression.Substring(2), null); + + if (expression[expression.Length - 1] != '}') + throw new Exception("Expression must end with '}'"); + + int len; + string match; + if (!MarkupExpressionParser.MatchMarkup(out match, expression, out len)) + throw new Exception(); + expression = expression.Substring(len).TrimStart(); + if (expression.Length == 0) + throw new Exception("Expression did not end in '}'"); + + var serviceProvider = new XamlServiceProvider(node, Context); + serviceProvider.Add(typeof (IXmlNamespaceResolver), nsResolver); + + return new MarkupExpansionParser().Parse(match, ref expression, serviceProvider); + } + + public class MarkupExpansionParser : MarkupExpressionParser, IExpressionParser<INode> + { + IElementNode node; + + object IExpressionParser.Parse(string match, ref string remaining, IServiceProvider serviceProvider) + { + return Parse(match, ref remaining, serviceProvider); + } + + public INode Parse(string match, ref string remaining, IServiceProvider serviceProvider) + { + var nsResolver = serviceProvider.GetService(typeof (IXmlNamespaceResolver)) as IXmlNamespaceResolver; + if (nsResolver == null) + throw new ArgumentException(); + IXmlLineInfo xmlLineInfo = null; + var xmlLineInfoProvider = serviceProvider.GetService(typeof (IXmlLineInfoProvider)) as IXmlLineInfoProvider; + if (xmlLineInfoProvider != null) + xmlLineInfo = xmlLineInfoProvider.XmlLineInfo; + + var split = match.Split(':'); + if (split.Length > 2) + throw new ArgumentException(); + + string prefix; //, name; + if (split.Length == 2) + { + prefix = split[0]; + // name = split [1]; + } + else + { + prefix = ""; + // name = split [0]; + } + + Type type; + var typeResolver = serviceProvider.GetService(typeof (IXamlTypeResolver)) as IXamlTypeResolver; + if (typeResolver == null) + type = null; + else + { + //The order of lookup is to look for the Extension-suffixed class name first and then look for the class name without the Extension suffix. + if (!typeResolver.TryResolve(match + "Extension", out type) && !typeResolver.TryResolve(match, out type)) + { + var lineInfoProvider = serviceProvider.GetService(typeof (IXmlLineInfoProvider)) as IXmlLineInfoProvider; + var lineInfo = (lineInfoProvider != null) ? lineInfoProvider.XmlLineInfo : new XmlLineInfo(); + throw new XamlParseException(String.Format("MarkupExtension not found for {0}", match), lineInfo); + } + } + + var namespaceuri = nsResolver.LookupNamespace(prefix) ?? ""; + var xmltype = new XmlType(namespaceuri, type.Name, null); + + if (type == null) + throw new NotSupportedException(); + + node = xmlLineInfo == null + ? new ElementNode(xmltype, null, nsResolver) + : new ElementNode(xmltype, null, nsResolver, xmlLineInfo.LineNumber, xmlLineInfo.LinePosition); + + if (remaining.StartsWith("}", StringComparison.Ordinal)) + { + remaining = remaining.Substring(1); + return node; + } + + char next; + string piece; + while ((piece = GetNextPiece(ref remaining, out next)) != null) + HandleProperty(piece, serviceProvider, ref remaining, next != '='); + + return node; + } + + protected override void SetPropertyValue(string prop, string strValue, object value, IServiceProvider serviceProvider) + { + var nsResolver = serviceProvider.GetService(typeof (IXmlNamespaceResolver)) as IXmlNamespaceResolver; + + var childnode = value as INode ?? new ValueNode(strValue, nsResolver); + childnode.Parent = node; + if (prop != null) + { + var name = new XmlName(node.NamespaceURI, prop); + node.Properties[name] = childnode; + } + else //ContentProperty + node.CollectionItems.Add(childnode); + } + } + } +}
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