Sic05/FrameworkLocal/UIClient/Caliburn.Micro/ViewModelBinder.cs

328 lines
13 KiB
C#

#if XFORMS
namespace Caliburn.Micro.Core.Xamarin.Forms
#else
namespace Caliburn.Micro
#endif
{
using System;
using System.Linq;
using System.Collections.Generic;
using System.Reflection;
using System.Threading.Tasks;
#if XFORMS
using UIElement = global::Xamarin.Forms.Element;
using FrameworkElement = global::Xamarin.Forms.VisualElement;
using DependencyProperty = global::Xamarin.Forms.BindableProperty;
using DependencyObject = global::Xamarin.Forms.BindableObject;
#elif WinRT81
using Windows.UI.Xaml;
using Microsoft.Xaml.Interactivity;
#else
using System.Windows;
using System.Windows.Interactivity;
using Caliburn.Micro.Core;
#endif
#if WINDOWS_PHONE
using Microsoft.Phone.Controls;
#endif
/// <summary>
/// Binds a view to a view model.
/// </summary>
public static class ViewModelBinder {
const string AsyncSuffix = "Async";
static readonly ILog Log = LogManager.GetLog(typeof(ViewModelBinder));
/// <summary>
/// Gets or sets a value indicating whether to apply conventions by default.
/// </summary>
/// <value>
/// <c>true</c> if conventions should be applied by default; otherwise, <c>false</c>.
/// </value>
public static bool ApplyConventionsByDefault = true;
/// <summary>
/// Indicates whether or not the conventions have already been applied to the view.
/// </summary>
public static readonly DependencyProperty ConventionsAppliedProperty =
DependencyPropertyHelper.RegisterAttached(
"ConventionsApplied",
typeof(bool),
typeof(ViewModelBinder),
false
);
/// <summary>
/// Determines whether a view should have conventions applied to it.
/// </summary>
/// <param name="view">The view to check.</param>
/// <returns>Whether or not conventions should be applied to the view.</returns>
public static bool ShouldApplyConventions(FrameworkElement view) {
var overriden = View.GetApplyConventions(view);
return overriden.GetValueOrDefault(ApplyConventionsByDefault);
}
/// <summary>
/// Creates data bindings on the view's controls based on the provided properties.
/// </summary>
/// <remarks>Parameters include named Elements to search through and the type of view model to determine conventions for. Returns unmatched elements.</remarks>
public static Func<IEnumerable<FrameworkElement>, Type, IEnumerable<FrameworkElement>> BindProperties = (namedElements, viewModelType) => {
var unmatchedElements = new List<FrameworkElement>();
#if !XFORMS
foreach (var element in namedElements) {
var cleanName = element.Name.Trim('_');
var parts = cleanName.Split(new[] { '_' }, StringSplitOptions.RemoveEmptyEntries);
var property = viewModelType.GetPropertyCaseInsensitive(parts[0]);
var interpretedViewModelType = viewModelType;
for (int i = 1; i < parts.Length && property != null; i++) {
interpretedViewModelType = property.PropertyType;
property = interpretedViewModelType.GetPropertyCaseInsensitive(parts[i]);
}
if (property == null) {
unmatchedElements.Add(element);
Log.Info("Binding Convention Not Applied: Element {0} did not match a property.", element.Name);
continue;
}
var convention = ConventionManager.GetElementConvention(element.GetType());
if (convention == null) {
unmatchedElements.Add(element);
Log.Warn("Binding Convention Not Applied: No conventions configured for {0}.", element.GetType());
continue;
}
var applied = convention.ApplyBinding(
interpretedViewModelType,
cleanName.Replace('_', '.'),
property,
element,
convention
);
if (applied) {
Log.Info("Binding Convention Applied: Element {0}.", element.Name);
}
else {
Log.Info("Binding Convention Not Applied: Element {0} has existing binding.", element.Name);
unmatchedElements.Add(element);
}
}
#endif
return unmatchedElements;
};
/// <summary>
/// Attaches instances of <see cref="ActionMessage"/> to the view's controls based on the provided methods.
/// </summary>
/// <remarks>Parameters include the named elements to search through and the type of view model to determine conventions for. Returns unmatched elements.</remarks>
public static Func<IEnumerable<FrameworkElement>, Type, IEnumerable<FrameworkElement>> BindActions = (namedElements, viewModelType) => {
var unmatchedElements = namedElements.ToList();
#if !XFORMS
#if WinRT || XFORMS
var methods = viewModelType.GetRuntimeMethods();
#else
var methods = viewModelType.GetMethods();
#endif
foreach (var method in methods) {
var foundControl = unmatchedElements.FindName(method.Name);
if (foundControl == null && IsAsyncMethod(method)) {
var methodNameWithoutAsyncSuffix = method.Name.Substring(0, method.Name.Length - AsyncSuffix.Length);
foundControl = unmatchedElements.FindName(methodNameWithoutAsyncSuffix);
}
if(foundControl == null) {
Log.Info("Action Convention Not Applied: No actionable element for {0}.", method.Name);
continue;
}
unmatchedElements.Remove(foundControl);
#if WinRT81
var triggers = Interaction.GetBehaviors(foundControl);
if (triggers != null && triggers.Count > 0)
{
Log.Info("Action Convention Not Applied: Interaction.Triggers already set on {0}.", foundControl.Name);
continue;
}
#endif
var message = method.Name;
var parameters = method.GetParameters();
if (parameters.Length > 0) {
message += "(";
foreach (var parameter in parameters) {
var paramName = parameter.Name;
var specialValue = "$" + paramName.ToLower();
if (MessageBinder.SpecialValues.ContainsKey(specialValue))
paramName = specialValue;
message += paramName + ",";
}
message = message.Remove(message.Length - 1, 1);
message += ")";
}
Log.Info("Action Convention Applied: Action {0} on element {1}.", method.Name, message);
Message.SetAttach(foundControl, message);
}
#endif
return unmatchedElements;
};
static bool IsAsyncMethod(MethodInfo method) {
return typeof(Task).IsAssignableFrom(method.ReturnType) &&
method.Name.EndsWith(AsyncSuffix, StringComparison.OrdinalIgnoreCase);
}
/// <summary>
/// Allows the developer to add custom handling of named elements which were not matched by any default conventions.
/// </summary>
public static Action<IEnumerable<FrameworkElement>, Type> HandleUnmatchedElements = (elements, viewModelType) => { };
/// <summary>
/// Binds the specified viewModel to the view.
/// </summary>
///<remarks>Passes the the view model, view and creation context (or null for default) to use in applying binding.</remarks>
public static Action<object, DependencyObject, object> Bind = (viewModel, view, context) => {
#if !WinRT && !XFORMS
// when using d:DesignInstance, Blend tries to assign the DesignInstanceExtension class as the DataContext,
// so here we get the actual ViewModel which is in the Instance property of DesignInstanceExtension
if (View.InDesignMode) {
var vmType = viewModel.GetType();
if (vmType.FullName == "Microsoft.Expression.DesignModel.InstanceBuilders.DesignInstanceExtension") {
var propInfo = vmType.GetProperty("Instance", BindingFlags.Instance | BindingFlags.NonPublic);
viewModel = propInfo.GetValue(viewModel, null);
}
}
#endif
Log.Info("Binding {0} and {1}.", view, viewModel);
#if XFORMS
var noContext = Caliburn.Micro.Xamarin.Forms.Bind.NoContextProperty;
#else
var noContext = Caliburn.Micro.Bind.NoContextProperty;
#endif
if ((bool)view.GetValue(noContext)) {
Action.SetTargetWithoutContext(view, viewModel);
}
else {
Action.SetTarget(view, viewModel);
}
var viewAware = viewModel as IViewAware;
if (viewAware != null) {
Log.Info("Attaching {0} to {1}.", view, viewAware);
viewAware.AttachView(view, context);
}
if ((bool)view.GetValue(ConventionsAppliedProperty)) {
return;
}
var element = View.GetFirstNonGeneratedView(view) as FrameworkElement;
if (element == null) {
return;
}
#if WINDOWS_PHONE
BindAppBar(view);
#endif
if (!ShouldApplyConventions(element)) {
Log.Info("Skipping conventions for {0} and {1}.", element, viewModel);
#if WINDOWS_PHONE
view.SetValue(ConventionsAppliedProperty, true); // we always apply the AppBar conventions
#endif
return;
}
var viewModelType = viewModel.GetType();
#if SL5 || NET45
var viewModelTypeProvider = viewModel as ICustomTypeProvider;
if (viewModelTypeProvider != null) {
viewModelType = viewModelTypeProvider.GetCustomType();
}
#endif
#if XFORMS
IEnumerable<FrameworkElement> namedElements = new List<FrameworkElement>();
#else
var namedElements = BindingScope.GetNamedElements(element);
#endif
#if SILVERLIGHT
namedElements.Apply(x => x.SetValue(
View.IsLoadedProperty,
element.GetValue(View.IsLoadedProperty))
);
#endif
namedElements = BindActions(namedElements, viewModelType);
namedElements = BindProperties(namedElements, viewModelType);
HandleUnmatchedElements(namedElements, viewModelType);
view.SetValue(ConventionsAppliedProperty, true);
};
#if WINDOWS_PHONE
static void BindAppBar(DependencyObject view) {
var page = view as PhoneApplicationPage;
if (page == null || page.ApplicationBar == null) {
return;
}
var triggers = Interaction.GetTriggers(view);
foreach(var item in page.ApplicationBar.Buttons) {
var button = item as IAppBarActionMessage;
if (button == null || string.IsNullOrEmpty(button.Message)) {
continue;
}
var parsedTrigger = Parser.Parse(view, button.Message).First();
var trigger = new AppBarItemTrigger(button);
var actionMessages = parsedTrigger.Actions.OfType<ActionMessage>().ToList();
actionMessages.Apply(x => {
x.applicationBarSource = button;
parsedTrigger.Actions.Remove(x);
trigger.Actions.Add(x);
});
triggers.Add(trigger);
}
foreach (var item in page.ApplicationBar.MenuItems) {
var menuItem = item as IAppBarActionMessage;
if (menuItem == null || string.IsNullOrEmpty(menuItem.Message)) {
continue;
}
var parsedTrigger = Parser.Parse(view, menuItem.Message).First();
var trigger = new AppBarItemTrigger(menuItem);
var actionMessages = parsedTrigger.Actions.OfType<ActionMessage>().ToList();
actionMessages.Apply(x => {
x.applicationBarSource = menuItem;
parsedTrigger.Actions.Remove(x);
trigger.Actions.Add(x);
});
triggers.Add(trigger);
}
}
#endif
}
}