dotnet/maui · error · XamlParseException

Can't resolve {name} on {type.Name}

Error message

Can't resolve {name} on {type.Name}

What it means

XamlParseException raised by ConvertFrom when, having resolved the owning Type and built the field name (propertyName + "Property"), GetPropertyField returns null or a field whose type is not BindableProperty. The named BindableProperty field simply does not exist on that type (public static, flattened up the hierarchy).

Source

Thrown at src/Controls/src/Core/BindablePropertyConverter.cs:102

				Application.Current?.FindMauiContext()?.CreateLogger<BindablePropertyConverter>()?.LogWarning("Can't resolve properties with xml namespace prefix.");
				return null;
			}
			string[] parts = strValue.Split('.');
			if (parts.Length != 2)
			{
				Application.Current?.FindMauiContext()?.CreateLogger<BindablePropertyConverter>()?.LogWarning($"Can't resolve {value}. Accepted syntax is Type.PropertyName.");
				return null;
			}
			Type type = GetControlType(parts[0]);
			return ConvertFrom(type, parts[1], null);
		}

		BindableProperty ConvertFrom(Type type, string propertyName, IXmlLineInfo lineinfo)
		{
			var name = propertyName + "Property";
			FieldInfo bpinfo = GetPropertyField(type, name);
			if (bpinfo == null || bpinfo.FieldType != typeof(BindableProperty))
				throw new XamlParseException($"Can't resolve {name} on {type.Name}", lineinfo);
			var bp = bpinfo.GetValue(null) as BindableProperty;
			var isObsolete = GetObsoleteAttribute(bpinfo) != null;
			if (bp.PropertyName != propertyName && !isObsolete)
				throw new XamlParseException($"The PropertyName of {type.Name}.{name} is not {propertyName}", lineinfo);
			return bp;
		}

		[UnconditionalSuppressMessage("TrimAnalysis", "IL2045:AttributeRemoval",
			Justification = "ObsoleteAttribute instances are removed by the trimmer in production builds.")]
		static ObsoleteAttribute GetObsoleteAttribute(FieldInfo fieldInfo)
			=> fieldInfo.GetCustomAttribute<ObsoleteAttribute>();

		[UnconditionalSuppressMessage("TrimAnalysis", "IL2057:TypeGetType",
			Justification = "The converter is only used when parsing XAML at runtime. The developer will receive a warning " +
				"saying that parsing XAML at runtime may not work as expected when trimming.")]
		static Type GetControlType(string typeName)
			=> Type.GetType("Microsoft.Maui.Controls." + typeName);

View on GitHub (pinned to f377ff1c5e)

Solutions

1. Verify the exact property name spelling against the control's API surface.
2. If the property was renamed, update the XAML to the new name.
3. Ensure the control version referenced actually declares that BindableProperty.

Example fix

<!-- before -->
<Setter Property="local:MyCtrl.Titel" Value="x" />

<!-- after -->
<Setter Property="local:MyCtrl.Title" Value="x" />

// Cross-check at authoring time: the type must expose a static BindableProperty field
// named <PropertyName>Property.
var fi = ownerType.GetProperty($"{propName}Property", BindingFlags.Public | BindingFlags.Static);
if (fi?.FieldType != typeof(BindableProperty)) /* flag the typo */

static bool PropertyExistsOnType(Type t, string propName) =>
    t.GetField(propName + "Property", BindingFlags.Public | BindingFlags.Static)?.FieldType
    == typeof(Microsoft.Maui.Controls.BindableProperty);

When it happens

Trigger: Property="MyCtrl.Foo" when MyCtrl has no FooProperty field; misspelling the property name; referencing a property that was renamed or removed; the field exists but is not declared as BindableProperty.

Common situations: Typo in property name; renaming a BindableProperty without updating XAML; referencing a control version where the property did not yet exist.

Related errors

• Can't resolve {parts[0]}
• Can't resolve {0}
• Can't resolve {value}. Syntax is [[prefix:]Type.]PropertyNam
• The PropertyName of {type.Name}.{name} is not {propertyName}
• XC0040

AI-assisted analysis of dotnet/maui@f377ff1c5e (2026-08-13). Data as JSON: /api/errors/39fc745c87e774c5. Report an issue: GitHub.