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using System;
using System.ComponentModel;
using RectangleF = CoreGraphics.CGRect;
using SizeF = CoreGraphics.CGSize;
#if __MOBILE__
using UIKit;
using NativeView = UIKit.UIView;
using NativeColor = UIKit.UIColor;
using NativeControl = UIKit.UIControl;
namespace Xamarin.Forms.Platform.iOS
#else
using NativeView = AppKit.NSView;
using NativeColor = CoreGraphics.CGColor;
using NativeControl = AppKit.NSControl;
namespace Xamarin.Forms.Platform.MacOS
#endif
{
public abstract class ViewRenderer : ViewRenderer<View, NativeView>
{
}
public abstract class ViewRenderer<TView, TNativeView> : VisualElementRenderer<TView> where TView : View where TNativeView : NativeView
{
#if __MOBILE__
string _defaultAccessibilityLabel;
string _defaultAccessibilityHint;
bool? _defaultIsAccessibilityElement;
#endif
NativeColor _defaultColor;
public TNativeView Control { get; private set; }
#if __MOBILE__
public override void LayoutSubviews()
{
base.LayoutSubviews();
if (Control != null)
Control.Frame = new RectangleF(0, 0, (nfloat)Element.Width, (nfloat)Element.Height);
}
public override SizeF SizeThatFits(SizeF size)
{
if (Control == null)
return (base.SizeThatFits(size));
return Control.SizeThatFits(size);
}
#else
public override SizeRequest GetDesiredSize(double widthConstraint, double heightConstraint)
{
return (Control ?? NativeView).GetSizeRequest(widthConstraint, heightConstraint);
}
public override void Layout()
{
if (Control != null)
Control.Frame = new RectangleF(0, 0, (nfloat)Element.Width, (nfloat)Element.Height);
base.Layout();
}
#endif
/// <summary>
/// Determines whether the native control is disposed of when this renderer is disposed
/// Can be overridden in deriving classes
/// </summary>
protected virtual bool ManageNativeControlLifetime => true;
protected override void Dispose(bool disposing)
{
base.Dispose(disposing);
if (disposing && Control != null && ManageNativeControlLifetime)
{
Control.RemoveFromSuperview();
Control.Dispose();
Control = null;
}
}
protected override void OnElementChanged(ElementChangedEventArgs<TView> e)
{
base.OnElementChanged(e);
if (e.OldElement != null)
e.OldElement.FocusChangeRequested -= ViewOnFocusChangeRequested;
if (e.NewElement != null)
{
if (Control != null && e.OldElement != null && e.OldElement.BackgroundColor != e.NewElement.BackgroundColor || e.NewElement.BackgroundColor != Color.Default)
SetBackgroundColor(e.NewElement.BackgroundColor);
e.NewElement.FocusChangeRequested += ViewOnFocusChangeRequested;
}
UpdateIsEnabled();
}
protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
{
if (Control != null)
{
if (e.PropertyName == VisualElement.IsEnabledProperty.PropertyName)
UpdateIsEnabled();
else if (e.PropertyName == VisualElement.BackgroundColorProperty.PropertyName)
SetBackgroundColor(Element.BackgroundColor);
}
base.OnElementPropertyChanged(sender, e);
}
protected override void OnRegisterEffect(PlatformEffect effect)
{
base.OnRegisterEffect(effect);
effect.SetControl(Control);
}
#if __MOBILE__
protected override void SetAccessibilityHint()
{
if (Control == null)
{
base.SetAccessibilityHint();
return;
}
if (Element == null)
return;
if (_defaultAccessibilityHint == null)
_defaultAccessibilityHint = Control.AccessibilityHint;
Control.AccessibilityHint = (string)Element.GetValue(AutomationProperties.HelpTextProperty) ?? _defaultAccessibilityHint;
}
protected override void SetAccessibilityLabel()
{
if (Control == null)
{
base.SetAccessibilityLabel();
return;
}
if (Element == null)
return;
if (_defaultAccessibilityLabel == null)
_defaultAccessibilityLabel = Control.AccessibilityLabel;
Control.AccessibilityLabel = (string)Element.GetValue(AutomationProperties.NameProperty) ?? _defaultAccessibilityLabel;
}
protected override void SetIsAccessibilityElement()
{
if (Control == null)
{
base.SetIsAccessibilityElement();
return;
}
if (Element == null)
return;
if (!_defaultIsAccessibilityElement.HasValue)
_defaultIsAccessibilityElement = Control.IsAccessibilityElement;
Control.IsAccessibilityElement = (bool)((bool?)Element.GetValue(AutomationProperties.IsInAccessibleTreeProperty) ?? _defaultIsAccessibilityElement);
}
#endif
protected override void SetAutomationId(string id)
{
if (Control == null)
base.SetAutomationId(id);
else
{
AccessibilityIdentifier = id + "_Container";
Control.AccessibilityIdentifier = id;
}
}
protected override void SetBackgroundColor(Color color)
{
if (Control == null)
return;
#if __MOBILE__
if (color == Color.Default)
Control.BackgroundColor = _defaultColor;
else
Control.BackgroundColor = color.ToUIColor();
#else
Control.Layer.BackgroundColor = color == Color.Default ? _defaultColor : color.ToCGColor();
#endif
}
protected void SetNativeControl(TNativeView uiview)
{
#if __MOBILE__
_defaultColor = uiview.BackgroundColor;
#else
uiview.WantsLayer = true;
_defaultColor = uiview.Layer.BackgroundColor;
#endif
Control = uiview;
if (Element.BackgroundColor != Color.Default)
SetBackgroundColor(Element.BackgroundColor);
UpdateIsEnabled();
AddSubview(uiview);
}
#if __MOBILE__
internal override void SendVisualElementInitialized(VisualElement element, NativeView nativeView)
{
base.SendVisualElementInitialized(element, Control);
}
#endif
void UpdateIsEnabled()
{
if (Element == null || Control == null)
return;
var uiControl = Control as NativeControl;
if (uiControl == null)
return;
uiControl.Enabled = Element.IsEnabled;
}
void ViewOnFocusChangeRequested(object sender, VisualElement.FocusRequestArgs focusRequestArgs)
{
if (Control == null)
return;
focusRequestArgs.Result = focusRequestArgs.Focus ? Control.BecomeFirstResponder() : Control.ResignFirstResponder();
}
}
}
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