public SimpleTriggerPage ()
{
var t = new Trigger (typeof(Entry));
t.Property = Entry.IsFocusedProperty;
t.Value = true;
t.Setters.Add (new Setter {Property = Entry.ScaleProperty, Value = 1.5 } );
var s = new Style (typeof(Entry));
s.Setters.Add (new Setter { Property = AnchorXProperty, Value = 0} );
s.Triggers.Add (t);
Resources = new ResourceDictionary ();
Resources.Add (s);
Padding = new Thickness (20, 50, 120, 0);
Content = new StackLayout {
Spacing = 20,
Children = {
new Entry { Placeholder = "enter name" },
new Entry { Placeholder = "enter address" },
new Entry { Placeholder = "enter city and name" },
}
};
}
public override BindableObject CreateTrigger(StyleSheet styleSheet, ITrigger trigger, Type targetType, BindableObject styleResourceReferenceHolder)
{
if (trigger == null)
{
throw new ArgumentNullException(nameof(trigger));
}
if (trigger is Trigger)
{
var propertyTrigger = trigger as Trigger;
var nativeTrigger = new Xamarin.Forms.Trigger(targetType);
var bindableProperty = dependencyService.GetDependencyProperty(targetType, propertyTrigger.Property);
if (bindableProperty == null)
{
throw new NullReferenceException($"Property '{propertyTrigger.Property}' may not be null (targetType '{targetType.Name}')!");
}
nativeTrigger.Property = bindableProperty;
nativeTrigger.Value = dependencyService.GetDependencyPropertyValue(targetType, nativeTrigger.Property.PropertyName, nativeTrigger.Property, propertyTrigger.Value);
foreach (var styleDeclaration in propertyTrigger.StyleDeclarationBlock)
{
var propertyInfo = typeNameResolver.GetDependencyPropertyInfo(styleSheet.Namespaces, targetType, styleDeclaration.Property);
if (propertyInfo == null)
{
continue;
}
try
{
var value = typeNameResolver.GetPropertyValue(propertyInfo.DeclaringType, styleResourceReferenceHolder, propertyInfo.Name, styleDeclaration.Value, propertyInfo.Property, styleSheet.Namespaces);
nativeTrigger.Setters.Add(new Setter {
Property = propertyInfo.Property, Value = value
});
}
catch (Exception e)
{
styleSheet.Errors.Add($@"ERROR in property trigger ""{propertyTrigger.Property} {propertyTrigger.Value} - {styleDeclaration.Property}: {styleDeclaration.Value}"": {e.Message}");
}
}
foreach (var action in propertyTrigger.EnterActions)
{
try
{
var nativeTriggerAction = CreateTriggerAction(styleSheet, styleResourceReferenceHolder, action);
nativeTrigger.EnterActions.Add(nativeTriggerAction);
}
catch (Exception e)
{
styleSheet.Errors.Add($@"ERROR in property trigger ""{propertyTrigger.Property} {propertyTrigger.Value}"" enter action: {e.Message}");
}
}
foreach (var action in propertyTrigger.ExitActions)
{
try
{
var nativeTriggerAction = CreateTriggerAction(styleSheet, styleResourceReferenceHolder, action);
nativeTrigger.ExitActions.Add(nativeTriggerAction);
}
catch (Exception e)
{
styleSheet.Errors.Add($@"ERROR in property trigger ""{propertyTrigger.Property} {propertyTrigger.Value}"" exit action: {e.Message}");
}
}
return(nativeTrigger);
}
else if (trigger is DataTrigger)
{
var dataTrigger = trigger as DataTrigger;
var nativeTrigger = new Xamarin.Forms.DataTrigger(targetType);
string expression = null;
if (typeNameResolver.IsMarkupExtension(dataTrigger.Binding))
{
expression = typeNameResolver.CreateMarkupExtensionExpression(dataTrigger.Binding);
}
else
{
expression = "{Binding " + dataTrigger.Binding + "}";
}
var binding = (Binding)markupExtensionParser.ProvideValue(expression, null, styleSheet.Namespaces);
nativeTrigger.Binding = binding;
nativeTrigger.Value = GetBasicValue(dataTrigger);
foreach (var styleDeclaration in dataTrigger.StyleDeclarationBlock)
{
try
{
var propertyInfo = typeNameResolver.GetDependencyPropertyInfo(styleSheet.Namespaces, targetType, styleDeclaration.Property);
if (propertyInfo == null)
{
continue;
}
var value = typeNameResolver.GetPropertyValue(propertyInfo.DeclaringType, styleResourceReferenceHolder, propertyInfo.Name, styleDeclaration.Value, propertyInfo.Property, styleSheet.Namespaces);
nativeTrigger.Setters.Add(new Setter {
Property = propertyInfo.Property, Value = value
});
}
catch (Exception e)
{
styleSheet.Errors.Add($@"ERROR in data trigger ""{dataTrigger.Binding} {dataTrigger.Value} - {styleDeclaration.Property}: {styleDeclaration.Value}"": {e.Message}");
}
}
foreach (var action in dataTrigger.EnterActions)
{
try
{
var nativeTriggerAction = CreateTriggerAction(styleSheet, styleResourceReferenceHolder, action);
nativeTrigger.EnterActions.Add(nativeTriggerAction);
}
catch (Exception e)
{
styleSheet.Errors.Add($@"ERROR in data trigger ""{dataTrigger.Binding} {dataTrigger.Value} - {action}"" enter action: {e.Message}");
}
}
foreach (var action in dataTrigger.ExitActions)
{
try
{
var nativeTriggerAction = CreateTriggerAction(styleSheet, styleResourceReferenceHolder, action);
nativeTrigger.ExitActions.Add(nativeTriggerAction);
}
catch (Exception e)
{
styleSheet.Errors.Add($@"ERROR in data trigger ""{dataTrigger.Binding} {dataTrigger.Value} - {action}"" exit action: {e.Message}");
}
}
return(nativeTrigger);
}
else if (trigger is EventTrigger)
{
var eventTrigger = trigger as EventTrigger;
var nativeTrigger = new Xamarin.Forms.EventTrigger();
nativeTrigger.Event = eventTrigger.Event;
foreach (var action in eventTrigger.Actions)
{
try
{
var nativeTriggerAction = CreateTriggerAction(styleSheet, styleResourceReferenceHolder, action);
nativeTrigger.Actions.Add(nativeTriggerAction);
}
catch (Exception e)
{
styleSheet.Errors.Add($@"ERROR in event trigger ""{eventTrigger.Event} {action.Action}"": {e.Message}");
}
}
return(nativeTrigger);
}
throw new NotSupportedException($"Trigger '{trigger.GetType().FullName}' is not supported!");
}
public override BindableObject CreateTrigger(StyleSheet styleSheet, ITrigger trigger, Type targetType, BindableObject styleResourceReferenceHolder)
{
if (trigger == null)
{
throw new ArgumentNullException(nameof(trigger));
}
if (trigger is Trigger)
{
var propertyTrigger = trigger as Trigger;
var nativeTrigger = new Xamarin.Forms.Trigger(targetType);
var bindableProperty = dependencyService.GetBindableProperty(targetType, propertyTrigger.Property);
if (bindableProperty == null)
{
throw new NullReferenceException($"Property '{propertyTrigger.Property}' may not be null (targetType '{targetType.Name}')!");
}
nativeTrigger.Property = bindableProperty;
nativeTrigger.Value = dependencyService.GetBindablePropertyValue(targetType, nativeTrigger.Property, propertyTrigger.Value);
foreach (var styleDeclaration in propertyTrigger.StyleDeclaraionBlock)
{
var property = typeNameResolver.GetDependencyProperty(styleSheet.Namespaces, targetType, styleDeclaration.Property);
if (property == null)
{
continue;
}
var value = typeNameResolver.GetPropertyValue(targetType, styleResourceReferenceHolder, styleDeclaration.Value, property);
nativeTrigger.Setters.Add(new Setter {
Property = property, Value = value
});
}
return(nativeTrigger);
}
else if (trigger is DataTrigger)
{
var dataTrigger = trigger as DataTrigger;
var nativeTrigger = new Xamarin.Forms.DataTrigger(targetType);
var expression = "{Binding " + dataTrigger.Binding + "}";
var binding = (Binding)markupExtensionParser.ProvideValue(expression, null);
nativeTrigger.Binding = binding;
nativeTrigger.Value = GetBasicValue(dataTrigger);
foreach (var styleDeclaration in dataTrigger.StyleDeclarationBlock)
{
var property = typeNameResolver.GetDependencyProperty(styleSheet.Namespaces, targetType, styleDeclaration.Property);
if (property == null)
{
continue;
}
var value = typeNameResolver.GetPropertyValue(targetType, styleResourceReferenceHolder, styleDeclaration.Value, property);
nativeTrigger.Setters.Add(new Setter {
Property = property, Value = value
});
}
return(nativeTrigger);
}
else if (trigger is EventTrigger)
{
var eventTrigger = trigger as EventTrigger;
var nativeTrigger = new Xamarin.Forms.EventTrigger();
nativeTrigger.Event = eventTrigger.Event;
foreach (var action in eventTrigger.Actions)
{
var actionTypeName = typeNameResolver.ResolveFullTypeName(styleSheet.Namespaces, action.Action);
var actionType = Type.GetType(actionTypeName);
var triggerAction = (Xamarin.Forms.TriggerAction)Activator.CreateInstance(actionType);
var parameters = action.Parameters.Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries)
.Select(x => x.Trim())
.ToList();
foreach (var parameter in parameters)
{
var parameterName = parameter.Split(' ')[0];
object value = null;
var parameterValueExpression = parameter.Substring(parameterName.Length + 1).Trim();
BindableProperty depProp;
var type = typeNameResolver.GetClrPropertyType(styleSheet.Namespaces, triggerAction, parameterName);
if (typeNameResolver.IsMarkupExtension(parameterValueExpression))
{
value = typeNameResolver.GetMarkupExtensionValue(styleResourceReferenceHolder, parameterValueExpression);
}
else if ((depProp = typeNameResolver.GetDependencyProperty(styleSheet.Namespaces, actionType, parameterName)) != null)
{
value = typeNameResolver.GetPropertyValue(actionType, styleResourceReferenceHolder, parameterValueExpression, depProp);
}
else
{
value = parameterValueExpression;
}
if (value is string valueString)
{
value = typeConverterProvider.GetConverter(type)?.ConvertFromInvariantString(valueString) ?? value;
}
triggerAction.GetType().GetRuntimeProperty(parameterName).SetValue(triggerAction, value);
}
nativeTrigger.Actions.Add(triggerAction);
}
return(nativeTrigger);
}
throw new NotSupportedException($"Trigger '{trigger.GetType().FullName}' is not supported!");
}