diff options
Diffstat (limited to 'Xamarin.Forms.Build.Tasks/SetNamescopesAndRegisterNamesVisitor.cs')
| -rw-r--r-- | Xamarin.Forms.Build.Tasks/SetNamescopesAndRegisterNamesVisitor.cs | 142 |
1 files changed, 142 insertions, 0 deletions
diff --git a/Xamarin.Forms.Build.Tasks/SetNamescopesAndRegisterNamesVisitor.cs b/Xamarin.Forms.Build.Tasks/SetNamescopesAndRegisterNamesVisitor.cs new file mode 100644 index 00000000..477328e2 --- /dev/null +++ b/Xamarin.Forms.Build.Tasks/SetNamescopesAndRegisterNamesVisitor.cs @@ -0,0 +1,142 @@ +using System.Linq; +using Mono.Cecil.Cil; +using Xamarin.Forms.Internals; +using Xamarin.Forms.Xaml; + +namespace Xamarin.Forms.Build.Tasks +{ + class SetNamescopesAndRegisterNamesVisitor : IXamlNodeVisitor + { + public SetNamescopesAndRegisterNamesVisitor(ILContext context) + { + Context = context; + } + + ILContext Context { get; } + + public bool VisitChildrenFirst + { + get { return false; } + } + + public bool StopOnDataTemplate + { + get { return true; } + } + + public bool StopOnResourceDictionary + { + get { return false; } + } + + public void Visit(ValueNode node, INode parentNode) + { + Context.Scopes[node] = Context.Scopes[parentNode]; + if (IsXNameProperty(node, parentNode)) + RegisterName((string)node.Value, Context.Scopes[node], Context.Variables[(IElementNode)parentNode], node); + } + + public void Visit(MarkupNode node, INode parentNode) + { + Context.Scopes[node] = Context.Scopes[parentNode]; + } + + public void Visit(ElementNode node, INode parentNode) + { + if (node.SkipPrefix((node.NamespaceResolver ?? parentNode.NamespaceResolver).LookupPrefix(node.NamespaceURI))) + return; + + VariableDefinition ns; + if (parentNode == null || IsDataTemplate(node, parentNode) || IsStyle(node, parentNode)) + ns = CreateNamescope(); + else + ns = Context.Scopes[parentNode]; + if ( + Context.Variables[node].VariableType.InheritsFromOrImplements( + Context.Body.Method.Module.Import(typeof (BindableObject)))) + SetNameScope(node, ns); + Context.Scopes[node] = ns; + } + + public void Visit(RootNode node, INode parentNode) + { + var ns = CreateNamescope(); + if ( + Context.Variables[node].VariableType.InheritsFromOrImplements( + Context.Body.Method.Module.Import(typeof (BindableObject)))) + SetNameScope(node, ns); + Context.Scopes[node] = ns; + } + + public void Visit(ListNode node, INode parentNode) + { + Context.Scopes[node] = Context.Scopes[parentNode]; + } + + static bool IsDataTemplate(INode node, INode parentNode) + { + var parentElement = parentNode as IElementNode; + INode createContent; + if (parentElement != null && parentElement.Properties.TryGetValue(XmlName._CreateContent, out createContent) && + createContent == node) + return true; + return false; + } + + static bool IsStyle(INode node, INode parentNode) + { + var pnode = parentNode as ElementNode; + return pnode != null && pnode.XmlType.Name == "Style"; + } + + static bool IsXNameProperty(ValueNode node, INode parentNode) + { + var parentElement = parentNode as IElementNode; + INode xNameNode; + if (parentElement != null && parentElement.Properties.TryGetValue(XmlName.xName, out xNameNode) && xNameNode == node) + return true; + return false; + } + + VariableDefinition CreateNamescope() + { + var module = Context.Body.Method.Module; + var nsRef = module.Import(typeof (NameScope)); + var vardef = new VariableDefinition(nsRef); + Context.Body.Variables.Add(vardef); + var nsDef = nsRef.Resolve(); + var ctorinfo = nsDef.Methods.First(md => md.IsConstructor && !md.HasParameters); + var ctor = module.Import(ctorinfo); + Context.IL.Emit(OpCodes.Newobj, ctor); + Context.IL.Emit(OpCodes.Stloc, vardef); + return vardef; + } + + void SetNameScope(ElementNode node, VariableDefinition ns) + { + var module = Context.Body.Method.Module; + var nsRef = module.Import(typeof (NameScope)); + var nsDef = nsRef.Resolve(); + var setNSInfo = nsDef.Methods.First(md => md.Name == "SetNameScope" && md.IsStatic); + var setNS = module.Import(setNSInfo); + Context.IL.Emit(OpCodes.Ldloc, Context.Variables[node]); + Context.IL.Emit(OpCodes.Ldloc, ns); + Context.IL.Emit(OpCodes.Call, setNS); + } + + void RegisterName(string str, VariableDefinition scope, VariableDefinition element, INode node) + { + var module = Context.Body.Method.Module; + var nsRef = module.Import(typeof (INameScope)); + var nsDef = nsRef.Resolve(); + var registerInfo = nsDef.Methods.First(md => md.Name == "RegisterName" && md.Parameters.Count == 3); + var register = module.Import(registerInfo); + + Context.IL.Emit(OpCodes.Ldloc, scope); + Context.IL.Emit(OpCodes.Ldstr, str); + Context.IL.Emit(OpCodes.Ldloc, element); + Context.IL.Append(node.PushXmlLineInfo(Context)); + Context.IL.Emit(OpCodes.Callvirt, register); + } + } +}
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