Steven Kirk
10 years ago
34 changed files with 789 additions and 565 deletions
@ -1,17 +0,0 @@ |
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// Copyright (c) The Avalonia Project. All rights reserved.
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// Licensed under the MIT license. See licence.md file in the project root for full license information.
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namespace Avalonia.Data |
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{ |
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/// <summary>
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/// Contains information on if the current object passed validation.
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/// Subclasses of this class contain additional information depending on the method of validation checking.
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/// </summary>
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public interface IValidationStatus |
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{ |
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/// <summary>
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/// True when the data passes validation; otherwise, false.
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/// </summary>
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bool IsValid { get; } |
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} |
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} |
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@ -1,44 +0,0 @@ |
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// Copyright (c) The Avalonia Project. All rights reserved.
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// Licensed under the MIT license. See licence.md file in the project root for full license information.
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using System; |
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using System.Collections.Generic; |
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using System.Linq; |
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namespace Avalonia.Data |
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{ |
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/// <summary>
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/// An immutable struct that contains validation information for a <see cref="AvaloniaObject"/> that validates a single property.
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/// </summary>
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public struct ObjectValidationStatus : IValidationStatus |
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{ |
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private Dictionary<Type, IValidationStatus> currentValidationStatus; |
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public bool IsValid => currentValidationStatus?.Values.All(status => status.IsValid) ?? true; |
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/// <summary>
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/// Constructs the structure with the given validation information.
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/// </summary>
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/// <param name="validations">The validation information</param>
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public ObjectValidationStatus(Dictionary<Type, IValidationStatus> validations) |
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:this() |
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{ |
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currentValidationStatus = validations; |
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} |
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/// <summary>
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/// Creates a new status with the updated information.
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/// </summary>
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/// <param name="status">The updated status information.</param>
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/// <returns>The new validation status.</returns>
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public ObjectValidationStatus UpdateValidationStatus(IValidationStatus status) |
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{ |
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var newStatus = new Dictionary<Type, IValidationStatus>(currentValidationStatus ?? |
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new Dictionary<Type, IValidationStatus>()); |
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newStatus[status.GetType()] = status; |
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return new ObjectValidationStatus(newStatus); |
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} |
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public IEnumerable<IValidationStatus> StatusInformation => currentValidationStatus.Values; |
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} |
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} |
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@ -0,0 +1,80 @@ |
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// Copyright (c) The Avalonia Project. All rights reserved.
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// Licensed under the MIT license. See licence.md file in the project root for full license information.
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using System; |
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using Avalonia.Data; |
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namespace Avalonia.Markup.Data.Plugins |
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{ |
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/// <summary>
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/// Base class for data validators.
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/// </summary>
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/// <remarks>
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/// Data validators are <see cref="IPropertyAccessor"/>s that are returned from an
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/// <see cref="IDataValidationPlugin"/>. They wrap an inner <see cref="IPropertyAccessor"/>
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/// and convert any values received from the inner property accessor into
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/// <see cref="BindingNotification"/>s.
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/// </remarks>
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public abstract class DataValidatiorBase : PropertyAccessorBase, IObserver<object> |
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{ |
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private readonly IPropertyAccessor _inner; |
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/// <summary>
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/// Initializes a new instance of the <see cref="DataValidatiorBase"/> class.
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/// </summary>
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/// <param name="inner">The inner property accessor.</param>
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protected DataValidatiorBase(IPropertyAccessor inner) |
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{ |
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_inner = inner; |
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} |
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/// <inheritdoc/>
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public override Type PropertyType => _inner.PropertyType; |
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/// <inheritdoc/>
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public override object Value => _inner.Value; |
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/// <inheritdoc/>
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public override bool SetValue(object value, BindingPriority priority) => _inner.SetValue(value, priority); |
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/// <summary>
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/// Should never be called: the inner <see cref="IPropertyAccessor"/> should never notify
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/// completion.
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/// </summary>
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void IObserver<object>.OnCompleted() { } |
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/// <summary>
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/// Should never be called: the inner <see cref="IPropertyAccessor"/> should never notify
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/// an error.
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/// </summary>
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void IObserver<object>.OnError(Exception error) { } |
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/// <summary>
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/// Called when the inner <see cref="IPropertyAccessor"/> notifies with a new value.
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/// </summary>
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/// <param name="value">The value.</param>
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void IObserver<object>.OnNext(object value) => InnerValueChanged(value); |
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/// <inheritdoc/>
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protected override void Dispose(bool disposing) => _inner.Dispose(); |
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/// <summary>
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/// Begins listening to the inner <see cref="IPropertyAccessor"/>.
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/// </summary>
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protected override void SubscribeCore(IObserver<object> observer) => _inner.Subscribe(this); |
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/// <summary>
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/// Called when the inner <see cref="IPropertyAccessor"/> notifies with a new value.
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/// </summary>
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/// <param name="value">The value.</param>
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/// <remarks>
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/// Notifies the observer that the value has changed. The value will be wrapped in a
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/// <see cref="BindingNotification"/> if it is not already a binding notification.
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/// </remarks>
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protected virtual void InnerValueChanged(object value) |
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{ |
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var notification = value as BindingNotification ?? new BindingNotification(value); |
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Observer.OnNext(notification); |
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} |
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} |
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} |
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@ -0,0 +1,36 @@ |
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// Copyright (c) The Avalonia Project. All rights reserved.
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// Licensed under the MIT license. See licence.md file in the project root for full license information.
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using System; |
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using Avalonia.Data; |
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namespace Avalonia.Markup.Data.Plugins |
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{ |
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/// <summary>
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/// Defines how data validation is observed by an <see cref="ExpressionObserver"/>.
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/// </summary>
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public interface IDataValidationPlugin |
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{ |
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/// <summary>
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/// Checks whether this plugin can handle data validation on the specified object.
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/// </summary>
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/// <param name="reference">A weak reference to the object.</param>
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/// <returns>True if the plugin can handle the object; otherwise false.</returns>
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bool Match(WeakReference reference); |
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/// <summary>
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/// Starts monitoring the data validation state of a property on an object.
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/// </summary>
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/// <param name="reference">A weak reference to the object.</param>
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/// <param name="propertyName">The property name.</param>
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/// <param name="inner">The inner property accessor used to aceess the property.</param>
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/// <returns>
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/// An <see cref="IPropertyAccessor"/> interface through which future interactions with the
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/// property will be made.
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/// </returns>
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IPropertyAccessor Start( |
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WeakReference reference, |
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string propertyName, |
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IPropertyAccessor inner); |
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} |
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} |
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@ -1,35 +0,0 @@ |
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// Copyright (c) The Avalonia Project. All rights reserved.
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// Licensed under the MIT license. See licence.md file in the project root for full license information.
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using System; |
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using Avalonia.Data; |
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namespace Avalonia.Markup.Data.Plugins |
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{ |
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/// <summary>
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/// Defines how view model data validation is observed by an <see cref="ExpressionObserver"/>.
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/// </summary>
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public interface IValidationPlugin |
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{ |
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/// <summary>
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/// Checks whether the data uses a validation scheme supported by this plugin.
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/// </summary>
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/// <param name="reference">A weak reference to the data.</param>
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/// <returns><c>true</c> if this plugin can observe the validation; otherwise, <c>false</c>.</returns>
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bool Match(WeakReference reference); |
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/// <summary>
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/// Starts monitoring the validation state of an object for the given property.
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/// </summary>
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/// <param name="reference">A weak reference to the object.</param>
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/// <param name="name">The property name.</param>
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/// <param name="accessor">An underlying <see cref="IPropertyAccessor"/> to access the property.</param>
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/// <param name="callback">A function to call when the validation state changes.</param>
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/// <returns>
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/// A <see cref="ValidatingPropertyAccessorBase"/> subclass through which future interactions with the
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/// property will be made.
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/// </returns>
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IPropertyAccessor Start(WeakReference reference, string name, IPropertyAccessor accessor, Action<IValidationStatus> callback); |
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} |
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} |
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@ -0,0 +1,68 @@ |
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// Copyright (c) The Avalonia Project. All rights reserved.
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// Licensed under the MIT license. See licence.md file in the project root for full license information.
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using System; |
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using Avalonia.Data; |
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namespace Avalonia.Markup.Data.Plugins |
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{ |
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/// <summary>
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/// Defines a default base implementation for a <see cref="IPropertyAccessor"/>.
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/// </summary>
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/// <remarks>
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/// <see cref="IPropertyAccessor"/> is an observable that will only be subscribed to one time.
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/// In addition, the subscription can be disposed by calling <see cref="Dispose()"/> on the
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/// property accessor itself - this prevents needing to hold two references for a subscription.
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/// </remarks>
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public abstract class PropertyAccessorBase : IPropertyAccessor |
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{ |
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/// <inheritdoc/>
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public abstract Type PropertyType { get; } |
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/// <inheritdoc/>
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public abstract object Value { get; } |
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/// <summary>
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/// Stops the subscription.
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/// </summary>
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public void Dispose() => Dispose(true); |
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/// <inheritdoc/>
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public abstract bool SetValue(object value, BindingPriority priority); |
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/// <summary>
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/// The currently subscribed observer.
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/// </summary>
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protected IObserver<object> Observer { get; private set; } |
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/// <inheritdoc/>
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public IDisposable Subscribe(IObserver<object> observer) |
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{ |
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Contract.Requires<ArgumentNullException>(observer != null); |
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if (Observer != null) |
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{ |
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throw new InvalidOperationException( |
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"A property accessor can be subscribed to only once."); |
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} |
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Observer = observer; |
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SubscribeCore(observer); |
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return this; |
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} |
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/// <summary>
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/// Stops listening to the property.
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/// </summary>
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/// <param name="disposing">
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/// True if the <see cref="Dispose()"/> method was called, false if the object is being
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/// finalized.
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/// </param>
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protected virtual void Dispose(bool disposing) => Observer = null; |
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/// <summary>
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/// When overridden in a derived class, begins listening to the property.
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/// </summary>
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protected abstract void SubscribeCore(IObserver<object> observer); |
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} |
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} |
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@ -1,46 +0,0 @@ |
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using System; |
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using Avalonia.Data; |
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namespace Avalonia.Markup.Data.Plugins |
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{ |
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/// <summary>
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/// A base class for validating <see cref="IPropertyAccessor"/>s that wraps an <see cref="IPropertyAccessor"/> and forwards method calls to it.
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/// </summary>
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public abstract class ValidatingPropertyAccessorBase : IPropertyAccessor |
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{ |
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protected readonly WeakReference _reference; |
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protected readonly string _name; |
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private readonly IPropertyAccessor _accessor; |
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private readonly Action<IValidationStatus> _callback; |
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protected ValidatingPropertyAccessorBase(WeakReference reference, string name, IPropertyAccessor accessor, Action<IValidationStatus> callback) |
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{ |
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_reference = reference; |
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_name = name; |
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_accessor = accessor; |
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_callback = callback; |
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} |
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/// <inheritdoc/>
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public Type PropertyType => _accessor.PropertyType; |
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/// <inheritdoc/>
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public object Value => _accessor.Value; |
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/// <inheritdoc/>
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public virtual void Dispose() => _accessor.Dispose(); |
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/// <inheritdoc/>
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public virtual bool SetValue(object value, BindingPriority priority) => _accessor.SetValue(value, priority); |
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/// <summary>
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/// Sends the validation status to the callback specified in construction.
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/// </summary>
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/// <param name="status">The validation status.</param>
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protected void SendValidationCallback(IValidationStatus status) |
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{ |
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_callback?.Invoke(status); |
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} |
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} |
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} |
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@ -1,93 +0,0 @@ |
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// Copyright (c) The Avalonia Project. All rights reserved.
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// Licensed under the MIT license. See licence.md file in the project root for full license information.
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using System; |
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using System.ComponentModel; |
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using System.Runtime.CompilerServices; |
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using Avalonia.Data; |
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using Avalonia.Markup.Data.Plugins; |
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using Xunit; |
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namespace Avalonia.Markup.UnitTests.Data |
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{ |
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public class ExceptionValidatorTests |
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{ |
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public class Data : INotifyPropertyChanged |
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{ |
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private int nonValidated; |
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public int NonValidated |
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{ |
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get { return nonValidated; } |
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set { nonValidated = value; NotifyPropertyChanged(); } |
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} |
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private int mustBePositive; |
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public int MustBePositive |
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{ |
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get { return mustBePositive; } |
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set |
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{ |
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if (value <= 0) |
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{ |
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throw new ArgumentOutOfRangeException(nameof(value)); |
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} |
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mustBePositive = value; |
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} |
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} |
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public event PropertyChangedEventHandler PropertyChanged; |
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private void NotifyPropertyChanged([CallerMemberName] string propertyName = "") |
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{ |
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PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName)); |
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} |
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} |
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[Fact] |
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public void Setting_Non_Validating_Triggers_Validation() |
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{ |
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var inpcAccessorPlugin = new InpcPropertyAccessorPlugin(); |
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var validatorPlugin = new ExceptionValidationPlugin(); |
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var data = new Data(); |
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var accessor = inpcAccessorPlugin.Start(new WeakReference(data), nameof(data.NonValidated), _ => { }); |
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IValidationStatus status = null; |
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var validator = validatorPlugin.Start(new WeakReference(data), nameof(data.NonValidated), accessor, s => status = s); |
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validator.SetValue(5, BindingPriority.LocalValue); |
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Assert.NotNull(status); |
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} |
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[Fact] |
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public void Setting_Validating_Property_To_Valid_Value_Returns_Successful_ValidationStatus() |
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{ |
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var inpcAccessorPlugin = new InpcPropertyAccessorPlugin(); |
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var validatorPlugin = new ExceptionValidationPlugin(); |
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var data = new Data(); |
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var accessor = inpcAccessorPlugin.Start(new WeakReference(data), nameof(data.MustBePositive), _ => { }); |
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IValidationStatus status = null; |
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var validator = validatorPlugin.Start(new WeakReference(data), nameof(data.MustBePositive), accessor, s => status = s); |
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validator.SetValue(5, BindingPriority.LocalValue); |
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Assert.True(status.IsValid); |
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} |
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[Fact] |
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public void Setting_Validating_Property_To_Invalid_Value_Returns_Failed_ValidationStatus() |
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{ |
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var inpcAccessorPlugin = new InpcPropertyAccessorPlugin(); |
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var validatorPlugin = new ExceptionValidationPlugin(); |
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var data = new Data(); |
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var accessor = inpcAccessorPlugin.Start(new WeakReference(data), nameof(data.MustBePositive), _ => { }); |
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IValidationStatus status = null; |
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var validator = validatorPlugin.Start(new WeakReference(data), nameof(data.MustBePositive), accessor, s => status = s); |
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validator.SetValue(-5, BindingPriority.LocalValue); |
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Assert.False(status.IsValid); |
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} |
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} |
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} |
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@ -0,0 +1,71 @@ |
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// Copyright (c) The Avalonia Project. All rights reserved.
|
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// Licensed under the MIT license. See licence.md file in the project root for full license information.
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|
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using System; |
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using System.Collections.Generic; |
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using System.ComponentModel; |
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using System.Reactive.Linq; |
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using System.Runtime.CompilerServices; |
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using Avalonia.Data; |
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using Avalonia.Markup.Data.Plugins; |
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using Xunit; |
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|
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namespace Avalonia.Markup.UnitTests.Data.Plugins |
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{ |
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public class ExceptionValidationPluginTests |
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{ |
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[Fact] |
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public void Produces_BindingNotifications() |
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{ |
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var inpcAccessorPlugin = new InpcPropertyAccessorPlugin(); |
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var validatorPlugin = new ExceptionValidationPlugin(); |
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var data = new Data(); |
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var accessor = inpcAccessorPlugin.Start(new WeakReference(data), nameof(data.MustBePositive)); |
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var validator = validatorPlugin.Start(new WeakReference(data), nameof(data.MustBePositive), accessor); |
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var result = new List<object>(); |
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validator.Subscribe(x => result.Add(x)); |
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validator.SetValue(5, BindingPriority.LocalValue); |
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validator.SetValue(-2, BindingPriority.LocalValue); |
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validator.SetValue(6, BindingPriority.LocalValue); |
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Assert.Equal(new[] |
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{ |
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new BindingNotification(0), |
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new BindingNotification(5), |
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new BindingNotification(new ArgumentOutOfRangeException("value"), BindingErrorType.DataValidationError), |
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new BindingNotification(6), |
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}, result); |
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} |
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|
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public class Data : INotifyPropertyChanged |
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{ |
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private int _mustBePositive; |
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|
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public int MustBePositive |
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{ |
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get { return _mustBePositive; } |
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set |
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{ |
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if (value <= 0) |
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{ |
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throw new ArgumentOutOfRangeException(nameof(value)); |
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} |
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|
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if (value != _mustBePositive) |
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{ |
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_mustBePositive = value; |
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NotifyPropertyChanged(); |
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} |
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} |
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} |
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|
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public event PropertyChangedEventHandler PropertyChanged; |
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|
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private void NotifyPropertyChanged([CallerMemberName] string propertyName = "") |
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{ |
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PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName)); |
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} |
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} |
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} |
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} |
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@ -0,0 +1,138 @@ |
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// Copyright (c) The Avalonia Project. All rights reserved.
|
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// Licensed under the MIT license. See licence.md file in the project root for full license information.
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|
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using System; |
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using System.Collections; |
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using System.Collections.Generic; |
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using System.ComponentModel; |
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using System.Reactive.Linq; |
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using Avalonia.Data; |
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using Avalonia.Markup.Data.Plugins; |
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using Xunit; |
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|
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namespace Avalonia.Markup.UnitTests.Data.Plugins |
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{ |
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public class IndeiValidationPluginTests |
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{ |
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[Fact] |
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public void Produces_BindingNotifications() |
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{ |
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var inpcAccessorPlugin = new InpcPropertyAccessorPlugin(); |
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var validatorPlugin = new IndeiValidationPlugin(); |
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var data = new Data { Maximum = 5 }; |
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var accessor = inpcAccessorPlugin.Start(new WeakReference(data), nameof(data.Value)); |
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var validator = validatorPlugin.Start(new WeakReference(data), nameof(data.Value), accessor); |
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var result = new List<object>(); |
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validator.Subscribe(x => result.Add(x)); |
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validator.SetValue(5, BindingPriority.LocalValue); |
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validator.SetValue(6, BindingPriority.LocalValue); |
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data.Maximum = 10; |
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data.Maximum = 5; |
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|
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Assert.Equal(new[] |
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{ |
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new BindingNotification(0), |
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new BindingNotification(5), |
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|
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// Value is first signalled without an error as validation hasn't been updated.
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new BindingNotification(6), |
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|
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// Then the ErrorsChanged event is fired.
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new BindingNotification(new Exception("Must be less than Maximum"), BindingErrorType.DataValidationError, 6), |
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|
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// Maximum is changed to 10 so value is now valid.
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new BindingNotification(6), |
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|||
// And Maximum is changed back to 5.
|
|||
new BindingNotification(new Exception("Must be less than Maximum"), BindingErrorType.DataValidationError, 6), |
|||
}, result); |
|||
} |
|||
|
|||
[Fact] |
|||
public void Subscribes_And_Unsubscribes() |
|||
{ |
|||
var inpcAccessorPlugin = new InpcPropertyAccessorPlugin(); |
|||
var validatorPlugin = new IndeiValidationPlugin(); |
|||
var data = new Data { Maximum = 5 }; |
|||
var accessor = inpcAccessorPlugin.Start(new WeakReference(data), nameof(data.Value)); |
|||
var validator = validatorPlugin.Start(new WeakReference(data), nameof(data.Value), accessor); |
|||
|
|||
Assert.Equal(0, data.SubscriptionCount); |
|||
var sub = validator.Subscribe(_ => { }); |
|||
Assert.Equal(1, data.SubscriptionCount); |
|||
sub.Dispose(); |
|||
Assert.Equal(0, data.SubscriptionCount); |
|||
} |
|||
|
|||
public class Data : INotifyDataErrorInfo, INotifyPropertyChanged |
|||
{ |
|||
private int _value; |
|||
private int _maximum; |
|||
private string _error; |
|||
private EventHandler<DataErrorsChangedEventArgs> _errorsChanged; |
|||
|
|||
public bool HasErrors => _error != null; |
|||
public int SubscriptionCount { get; private set; } |
|||
|
|||
public int Value |
|||
{ |
|||
get { return _value; } |
|||
set |
|||
{ |
|||
_value = value; |
|||
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(nameof(Value))); |
|||
UpdateError(); |
|||
} |
|||
} |
|||
|
|||
public int Maximum |
|||
{ |
|||
get { return _maximum; } |
|||
set |
|||
{ |
|||
_maximum = value; |
|||
UpdateError(); |
|||
} |
|||
} |
|||
|
|||
public event EventHandler<DataErrorsChangedEventArgs> ErrorsChanged |
|||
{ |
|||
add { _errorsChanged += value; ++SubscriptionCount; } |
|||
remove { _errorsChanged -= value; --SubscriptionCount; } |
|||
} |
|||
|
|||
public event PropertyChangedEventHandler PropertyChanged; |
|||
|
|||
public IEnumerable GetErrors(string propertyName) |
|||
{ |
|||
if (propertyName == nameof(Value) && _error != null) |
|||
{ |
|||
return new[] { _error }; |
|||
} |
|||
|
|||
return null; |
|||
} |
|||
|
|||
private void UpdateError() |
|||
{ |
|||
if (_value <= _maximum) |
|||
{ |
|||
if (_error != null) |
|||
{ |
|||
_error = null; |
|||
_errorsChanged?.Invoke(this, new DataErrorsChangedEventArgs(nameof(Value))); |
|||
} |
|||
} |
|||
else |
|||
{ |
|||
if (_error == null) |
|||
{ |
|||
_error = "Must be less than Maximum"; |
|||
_errorsChanged?.Invoke(this, new DataErrorsChangedEventArgs(nameof(Value))); |
|||
} |
|||
} |
|||
} |
|||
} |
|||
} |
|||
} |
|||
Loading…
Reference in new issue