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diff --git a/Xamarin.Forms.Core/BindableProperty.cs b/Xamarin.Forms.Core/BindableProperty.cs
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+´╗┐using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq.Expressions;
+using System.Reflection;
+
+namespace Xamarin.Forms
+{
+ [DebuggerDisplay("{PropertyName}")]
+ [TypeConverter(typeof(BindablePropertyConverter))]
+ public sealed class BindableProperty
+ {
+ public delegate void BindingPropertyChangedDelegate(BindableObject bindable, object oldValue, object newValue);
+
+ public delegate void BindingPropertyChangedDelegate<in TPropertyType>(BindableObject bindable, TPropertyType oldValue, TPropertyType newValue);
+
+ public delegate void BindingPropertyChangingDelegate(BindableObject bindable, object oldValue, object newValue);
+
+ public delegate void BindingPropertyChangingDelegate<in TPropertyType>(BindableObject bindable, TPropertyType oldValue, TPropertyType newValue);
+
+ public delegate object CoerceValueDelegate(BindableObject bindable, object value);
+
+ public delegate TPropertyType CoerceValueDelegate<TPropertyType>(BindableObject bindable, TPropertyType value);
+
+ public delegate object CreateDefaultValueDelegate(BindableObject bindable);
+
+ public delegate TPropertyType CreateDefaultValueDelegate<in TDeclarer, out TPropertyType>(TDeclarer bindable);
+
+ public delegate bool ValidateValueDelegate(BindableObject bindable, object value);
+
+ public delegate bool ValidateValueDelegate<in TPropertyType>(BindableObject bindable, TPropertyType value);
+
+ // more or less the encoding of this, without the need to reflect
+ // http://msdn.microsoft.com/en-us/library/y5b434w4.aspx
+ static readonly Dictionary<Type, Type[]> SimpleConvertTypes = new Dictionary<Type, Type[]>
+ {
+ { typeof(sbyte), new[] { typeof(string), typeof(short), typeof(int), typeof(long), typeof(float), typeof(double), typeof(decimal) } },
+ { typeof(byte), new[] { typeof(string), typeof(short), typeof(ushort), typeof(int), typeof(uint), typeof(ulong), typeof(float), typeof(double), typeof(decimal) } },
+ { typeof(short), new[] { typeof(string), typeof(int), typeof(long), typeof(float), typeof(double), typeof(decimal) } },
+ { typeof(ushort), new[] { typeof(string), typeof(int), typeof(uint), typeof(long), typeof(ulong), typeof(float), typeof(double), typeof(decimal) } },
+ { typeof(int), new[] { typeof(string), typeof(long), typeof(float), typeof(double), typeof(decimal) } },
+ { typeof(uint), new[] { typeof(string), typeof(long), typeof(ulong), typeof(float), typeof(double), typeof(decimal) } },
+ { typeof(long), new[] { typeof(string), typeof(float), typeof(double), typeof(decimal) } },
+ { typeof(char), new[] { typeof(string), typeof(ushort), typeof(int), typeof(uint), typeof(long), typeof(ulong), typeof(float), typeof(double), typeof(decimal) } },
+ { typeof(float), new[] { typeof(string), typeof(double) } },
+ { typeof(ulong), new[] { typeof(string), typeof(float), typeof(double), typeof(decimal) } }
+ };
+
+ BindableProperty(string propertyName, Type returnType, Type declaringType, object defaultValue, BindingMode defaultBindingMode = BindingMode.OneWay,
+ ValidateValueDelegate validateValue = null, BindingPropertyChangedDelegate propertyChanged = null, BindingPropertyChangingDelegate propertyChanging = null,
+ CoerceValueDelegate coerceValue = null, BindablePropertyBindingChanging bindingChanging = null, bool isReadOnly = false, CreateDefaultValueDelegate defaultValueCreator = null)
+ {
+ if (propertyName == null)
+ throw new ArgumentNullException("propertyName");
+ if (ReferenceEquals(returnType, null))
+ throw new ArgumentNullException("returnType");
+ if (ReferenceEquals(declaringType, null))
+ throw new ArgumentNullException("declaringType");
+
+ // don't use Enum.IsDefined as its redonkulously expensive for what it does
+ if (defaultBindingMode != BindingMode.Default && defaultBindingMode != BindingMode.OneWay && defaultBindingMode != BindingMode.OneWayToSource && defaultBindingMode != BindingMode.TwoWay)
+ throw new ArgumentException("Not a valid type of BindingMode", "defaultBindingMode");
+ if (defaultValue == null && Nullable.GetUnderlyingType(returnType) == null && returnType.GetTypeInfo().IsValueType)
+ throw new ArgumentException("Not a valid default value", "defaultValue");
+ if (defaultValue != null && !returnType.IsInstanceOfType(defaultValue))
+ throw new ArgumentException("Default value did not match return type", "defaultValue");
+ if (defaultBindingMode == BindingMode.Default)
+ defaultBindingMode = BindingMode.OneWay;
+
+ PropertyName = propertyName;
+ ReturnType = returnType;
+ ReturnTypeInfo = returnType.GetTypeInfo();
+ DeclaringType = declaringType;
+ DefaultValue = defaultValue;
+ DefaultBindingMode = defaultBindingMode;
+ PropertyChanged = propertyChanged;
+ PropertyChanging = propertyChanging;
+ ValidateValue = validateValue;
+ CoerceValue = coerceValue;
+ BindingChanging = bindingChanging;
+ IsReadOnly = isReadOnly;
+ DefaultValueCreator = defaultValueCreator;
+ }
+
+ public Type DeclaringType { get; private set; }
+
+ public BindingMode DefaultBindingMode { get; private set; }
+
+ public object DefaultValue { get; }
+
+ public bool IsReadOnly { get; private set; }
+
+ public string PropertyName { get; }
+
+ public Type ReturnType { get; }
+
+ internal BindablePropertyBindingChanging BindingChanging { get; private set; }
+
+ internal CoerceValueDelegate CoerceValue { get; private set; }
+
+ internal CreateDefaultValueDelegate DefaultValueCreator { get; }
+
+ internal BindingPropertyChangedDelegate PropertyChanged { get; private set; }
+
+ internal BindingPropertyChangingDelegate PropertyChanging { get; private set; }
+
+ internal TypeInfo ReturnTypeInfo { get; }
+
+ internal ValidateValueDelegate ValidateValue { get; private set; }
+
+ [Obsolete("Generic versions of Create () are no longer supported and deprecated. They will be removed soon.")]
+ public static BindableProperty Create<TDeclarer, TPropertyType>(Expression<Func<TDeclarer, TPropertyType>> getter, TPropertyType defaultValue, BindingMode defaultBindingMode = BindingMode.OneWay,
+ ValidateValueDelegate<TPropertyType> validateValue = null, BindingPropertyChangedDelegate<TPropertyType> propertyChanged = null,
+ BindingPropertyChangingDelegate<TPropertyType> propertyChanging = null, CoerceValueDelegate<TPropertyType> coerceValue = null,
+ CreateDefaultValueDelegate<TDeclarer, TPropertyType> defaultValueCreator = null) where TDeclarer : BindableObject
+ {
+ return Create(getter, defaultValue, defaultBindingMode, validateValue, propertyChanged, propertyChanging, coerceValue, null, defaultValueCreator: defaultValueCreator);
+ }
+
+ public static BindableProperty Create(string propertyName, Type returnType, Type declaringType, object defaultValue = null, BindingMode defaultBindingMode = BindingMode.OneWay,
+ ValidateValueDelegate validateValue = null, BindingPropertyChangedDelegate propertyChanged = null, BindingPropertyChangingDelegate propertyChanging = null,
+ CoerceValueDelegate coerceValue = null, CreateDefaultValueDelegate defaultValueCreator = null)
+ {
+ return new BindableProperty(propertyName, returnType, declaringType, defaultValue, defaultBindingMode, validateValue, propertyChanged, propertyChanging, coerceValue,
+ defaultValueCreator: defaultValueCreator);
+ }
+
+ [Obsolete("Generic versions of Create () are no longer supported and deprecated. They will be removed soon.")]
+ public static BindableProperty CreateAttached<TDeclarer, TPropertyType>(Expression<Func<BindableObject, TPropertyType>> staticgetter, TPropertyType defaultValue,
+ BindingMode defaultBindingMode = BindingMode.OneWay, ValidateValueDelegate<TPropertyType> validateValue = null, BindingPropertyChangedDelegate<TPropertyType> propertyChanged = null,
+ BindingPropertyChangingDelegate<TPropertyType> propertyChanging = null, CoerceValueDelegate<TPropertyType> coerceValue = null,
+ CreateDefaultValueDelegate<BindableObject, TPropertyType> defaultValueCreator = null)
+ {
+ return CreateAttached<TDeclarer, TPropertyType>(staticgetter, defaultValue, defaultBindingMode, validateValue, propertyChanged, propertyChanging, coerceValue, null,
+ defaultValueCreator: defaultValueCreator);
+ }
+
+ public static BindableProperty CreateAttached(string propertyName, Type returnType, Type declaringType, object defaultValue, BindingMode defaultBindingMode = BindingMode.OneWay,
+ ValidateValueDelegate validateValue = null, BindingPropertyChangedDelegate propertyChanged = null, BindingPropertyChangingDelegate propertyChanging = null,
+ CoerceValueDelegate coerceValue = null, CreateDefaultValueDelegate defaultValueCreator = null)
+ {
+ return CreateAttached(propertyName, returnType, declaringType, defaultValue, defaultBindingMode, validateValue, propertyChanged, propertyChanging, coerceValue, null, false, defaultValueCreator);
+ }
+
+ [Obsolete("Generic versions of Create () are no longer supported and deprecated. They will be removed soon.")]
+ public static BindablePropertyKey CreateAttachedReadOnly<TDeclarer, TPropertyType>(Expression<Func<BindableObject, TPropertyType>> staticgetter, TPropertyType defaultValue,
+ BindingMode defaultBindingMode = BindingMode.OneWayToSource, ValidateValueDelegate<TPropertyType> validateValue = null,
+ BindingPropertyChangedDelegate<TPropertyType> propertyChanged = null, BindingPropertyChangingDelegate<TPropertyType> propertyChanging = null,
+ CoerceValueDelegate<TPropertyType> coerceValue = null, CreateDefaultValueDelegate<BindableObject, TPropertyType> defaultValueCreator = null)
+
+ {
+ return
+ new BindablePropertyKey(CreateAttached<TDeclarer, TPropertyType>(staticgetter, defaultValue, defaultBindingMode, validateValue, propertyChanged, propertyChanging, coerceValue, null, true,
+ defaultValueCreator));
+ }
+
+ public static BindablePropertyKey CreateAttachedReadOnly(string propertyName, Type returnType, Type declaringType, object defaultValue, BindingMode defaultBindingMode = BindingMode.OneWayToSource,
+ ValidateValueDelegate validateValue = null, BindingPropertyChangedDelegate propertyChanged = null, BindingPropertyChangingDelegate propertyChanging = null,
+ CoerceValueDelegate coerceValue = null, CreateDefaultValueDelegate defaultValueCreator = null)
+ {
+ return
+ new BindablePropertyKey(CreateAttached(propertyName, returnType, declaringType, defaultValue, defaultBindingMode, validateValue, propertyChanged, propertyChanging, coerceValue, null, true,
+ defaultValueCreator));
+ }
+
+ [Obsolete("Generic versions of Create () are no longer supported and deprecated. They will be removed soon.")]
+ public static BindablePropertyKey CreateReadOnly<TDeclarer, TPropertyType>(Expression<Func<TDeclarer, TPropertyType>> getter, TPropertyType defaultValue,
+ BindingMode defaultBindingMode = BindingMode.OneWayToSource, ValidateValueDelegate<TPropertyType> validateValue = null,
+ BindingPropertyChangedDelegate<TPropertyType> propertyChanged = null, BindingPropertyChangingDelegate<TPropertyType> propertyChanging = null,
+ CoerceValueDelegate<TPropertyType> coerceValue = null, CreateDefaultValueDelegate<TDeclarer, TPropertyType> defaultValueCreator = null) where TDeclarer : BindableObject
+ {
+ return new BindablePropertyKey(Create(getter, defaultValue, defaultBindingMode, validateValue, propertyChanged, propertyChanging, coerceValue, null, true, defaultValueCreator));
+ }
+
+ public static BindablePropertyKey CreateReadOnly(string propertyName, Type returnType, Type declaringType, object defaultValue, BindingMode defaultBindingMode = BindingMode.OneWayToSource,
+ ValidateValueDelegate validateValue = null, BindingPropertyChangedDelegate propertyChanged = null, BindingPropertyChangingDelegate propertyChanging = null,
+ CoerceValueDelegate coerceValue = null, CreateDefaultValueDelegate defaultValueCreator = null)
+ {
+ return
+ new BindablePropertyKey(new BindableProperty(propertyName, returnType, declaringType, defaultValue, defaultBindingMode, validateValue, propertyChanged, propertyChanging, coerceValue,
+ isReadOnly: true, defaultValueCreator: defaultValueCreator));
+ }
+
+ [Obsolete("Generic versions of Create () are no longer supported and deprecated. They will be removed soon.")]
+ internal static BindableProperty Create<TDeclarer, TPropertyType>(Expression<Func<TDeclarer, TPropertyType>> getter, TPropertyType defaultValue, BindingMode defaultBindingMode,
+ ValidateValueDelegate<TPropertyType> validateValue, BindingPropertyChangedDelegate<TPropertyType> propertyChanged, BindingPropertyChangingDelegate<TPropertyType> propertyChanging,
+ CoerceValueDelegate<TPropertyType> coerceValue, BindablePropertyBindingChanging bindingChanging, bool isReadOnly = false,
+ CreateDefaultValueDelegate<TDeclarer, TPropertyType> defaultValueCreator = null) where TDeclarer : BindableObject
+ {
+ if (getter == null)
+ throw new ArgumentNullException("getter");
+
+ Expression expr = getter.Body;
+
+ var unary = expr as UnaryExpression;
+ if (unary != null)
+ expr = unary.Operand;
+
+ var member = expr as MemberExpression;
+ if (member == null)
+ throw new ArgumentException("getter must be a MemberExpression", "getter");
+
+ var property = (PropertyInfo)member.Member;
+
+ ValidateValueDelegate untypedValidateValue = null;
+ BindingPropertyChangedDelegate untypedBindingPropertyChanged = null;
+ BindingPropertyChangingDelegate untypedBindingPropertyChanging = null;
+ CoerceValueDelegate untypedCoerceValue = null;
+ CreateDefaultValueDelegate untypedDefaultValueCreator = null;
+ if (validateValue != null)
+ untypedValidateValue = (bindable, value) => validateValue(bindable, (TPropertyType)value);
+ if (propertyChanged != null)
+ untypedBindingPropertyChanged = (bindable, oldValue, newValue) => propertyChanged(bindable, (TPropertyType)oldValue, (TPropertyType)newValue);
+ if (propertyChanging != null)
+ untypedBindingPropertyChanging = (bindable, oldValue, newValue) => propertyChanging(bindable, (TPropertyType)oldValue, (TPropertyType)newValue);
+ if (coerceValue != null)
+ untypedCoerceValue = (bindable, value) => coerceValue(bindable, (TPropertyType)value);
+ if (defaultValueCreator != null)
+ untypedDefaultValueCreator = o => defaultValueCreator((TDeclarer)o);
+
+ return new BindableProperty(property.Name, property.PropertyType, typeof(TDeclarer), defaultValue, defaultBindingMode, untypedValidateValue, untypedBindingPropertyChanged,
+ untypedBindingPropertyChanging, untypedCoerceValue, bindingChanging, isReadOnly, untypedDefaultValueCreator);
+ }
+
+ internal static BindableProperty Create(string propertyName, Type returnType, Type declaringType, object defaultValue, BindingMode defaultBindingMode, ValidateValueDelegate validateValue,
+ BindingPropertyChangedDelegate propertyChanged, BindingPropertyChangingDelegate propertyChanging, CoerceValueDelegate coerceValue, BindablePropertyBindingChanging bindingChanging,
+ CreateDefaultValueDelegate defaultValueCreator = null)
+ {
+ return new BindableProperty(propertyName, returnType, declaringType, defaultValue, defaultBindingMode, validateValue, propertyChanged, propertyChanging, coerceValue, bindingChanging,
+ defaultValueCreator: defaultValueCreator);
+ }
+
+ [Obsolete("Generic versions of Create () are no longer supported and deprecated. They will be removed soon.")]
+ internal static BindableProperty CreateAttached<TDeclarer, TPropertyType>(Expression<Func<BindableObject, TPropertyType>> staticgetter, TPropertyType defaultValue, BindingMode defaultBindingMode,
+ ValidateValueDelegate<TPropertyType> validateValue, BindingPropertyChangedDelegate<TPropertyType> propertyChanged, BindingPropertyChangingDelegate<TPropertyType> propertyChanging,
+ CoerceValueDelegate<TPropertyType> coerceValue, BindablePropertyBindingChanging bindingChanging, bool isReadOnly = false,
+ CreateDefaultValueDelegate<BindableObject, TPropertyType> defaultValueCreator = null)
+ {
+ if (staticgetter == null)
+ throw new ArgumentNullException("staticgetter");
+
+ Expression expr = staticgetter.Body;
+
+ var unary = expr as UnaryExpression;
+ if (unary != null)
+ expr = unary.Operand;
+
+ var methodcall = expr as MethodCallExpression;
+ if (methodcall == null)
+ throw new ArgumentException("staticgetter must be a MethodCallExpression", "staticgetter");
+
+ MethodInfo method = methodcall.Method;
+ if (!method.Name.StartsWith("Get", StringComparison.Ordinal))
+ throw new ArgumentException("staticgetter name must start with Get", "staticgetter");
+
+ string propertyname = method.Name.Substring(3);
+
+ ValidateValueDelegate untypedValidateValue = null;
+ BindingPropertyChangedDelegate untypedBindingPropertyChanged = null;
+ BindingPropertyChangingDelegate untypedBindingPropertyChanging = null;
+ CoerceValueDelegate untypedCoerceValue = null;
+ CreateDefaultValueDelegate untypedDefaultValueCreator = null;
+ if (validateValue != null)
+ untypedValidateValue = (bindable, value) => validateValue(bindable, (TPropertyType)value);
+ if (propertyChanged != null)
+ untypedBindingPropertyChanged = (bindable, oldValue, newValue) => propertyChanged(bindable, (TPropertyType)oldValue, (TPropertyType)newValue);
+ if (propertyChanging != null)
+ untypedBindingPropertyChanging = (bindable, oldValue, newValue) => propertyChanging(bindable, (TPropertyType)oldValue, (TPropertyType)newValue);
+ if (coerceValue != null)
+ untypedCoerceValue = (bindable, value) => coerceValue(bindable, (TPropertyType)value);
+ if (defaultValueCreator != null)
+ untypedDefaultValueCreator = o => defaultValueCreator(o);
+
+ return new BindableProperty(propertyname, method.ReturnType, typeof(TDeclarer), defaultValue, defaultBindingMode, untypedValidateValue, untypedBindingPropertyChanged, untypedBindingPropertyChanging,
+ untypedCoerceValue, bindingChanging, isReadOnly, untypedDefaultValueCreator);
+ }
+
+ internal static BindableProperty CreateAttached(string propertyName, Type returnType, Type declaringType, object defaultValue, BindingMode defaultBindingMode, ValidateValueDelegate validateValue,
+ BindingPropertyChangedDelegate propertyChanged, BindingPropertyChangingDelegate propertyChanging, CoerceValueDelegate coerceValue, BindablePropertyBindingChanging bindingChanging,
+ bool isReadOnly, CreateDefaultValueDelegate defaultValueCreator = null)
+ {
+ return new BindableProperty(propertyName, returnType, declaringType, defaultValue, defaultBindingMode, validateValue, propertyChanged, propertyChanging, coerceValue, bindingChanging, isReadOnly,
+ defaultValueCreator);
+ }
+
+ internal object GetDefaultValue(BindableObject bindable)
+ {
+ if (DefaultValueCreator != null)
+ return DefaultValueCreator(bindable);
+
+ return DefaultValue;
+ }
+
+ internal bool TryConvert(ref object value)
+ {
+ if (value == null)
+ {
+ return !ReturnTypeInfo.IsValueType || ReturnTypeInfo.IsGenericType && ReturnTypeInfo.GetGenericTypeDefinition() == typeof(Nullable<>);
+ }
+
+ Type valueType = value.GetType();
+ Type type = ReturnType;
+
+ // Dont support arbitrary IConvertible by limiting which types can use this
+ Type[] convertableTo;
+ if (SimpleConvertTypes.TryGetValue(valueType, out convertableTo) && Array.IndexOf(convertableTo, type) != -1)
+ {
+ value = Convert.ChangeType(value, type);
+ }
+ else if (!ReturnTypeInfo.IsAssignableFrom(valueType.GetTypeInfo()))
+ {
+ // Is there an implicit cast operator ?
+ MethodInfo cast = type.GetRuntimeMethod("op_Implicit", new[] { valueType });
+ if (cast != null && cast.ReturnType != type)
+ cast = null;
+ if (cast == null)
+ cast = valueType.GetRuntimeMethod("op_Implicit", new[] { valueType });
+ if (cast != null && cast.ReturnType != type)
+ cast = null;
+ if (cast == null)
+ return false;
+
+ value = cast.Invoke(null, new[] { value });
+ }
+
+ return true;
+ }
+
+ internal delegate void BindablePropertyBindingChanging(BindableObject bindable, BindingBase oldValue, BindingBase newValue);
+ }
+} \ No newline at end of file