using System; using Android.Widget; using ASwitch = Android.Widget.Switch; namespace Xamarin.Forms.Platform.Android { public class SwitchRenderer : ViewRenderer, CompoundButton.IOnCheckedChangeListener { public SwitchRenderer() { AutoPackage = false; } void CompoundButton.IOnCheckedChangeListener.OnCheckedChanged(CompoundButton buttonView, bool isChecked) { ((IViewController)Element).SetValueFromRenderer(Switch.IsToggledProperty, isChecked); } public override SizeRequest GetDesiredSize(int widthConstraint, int heightConstraint) { SizeRequest sizeConstraint = base.GetDesiredSize(widthConstraint, heightConstraint); if (sizeConstraint.Request.Width == 0) { int width = widthConstraint; if (widthConstraint <= 0) width = (int)Context.GetThemeAttributeDp(global::Android.Resource.Attribute.SwitchMinWidth); else if (widthConstraint <= 0) width = 100; sizeConstraint = new SizeRequest(new Size(width, sizeConstraint.Request.Height), new Size(width, sizeConstraint.Minimum.Height)); } return sizeConstraint; } protected override void Dispose(bool disposing) { if (disposing && Control != null) { if (Element != null) Element.Toggled -= HandleToggled; Control.SetOnCheckedChangeListener(null); } base.Dispose(disposing); } protected override ASwitch CreateNativeControl() { return new ASwitch(Context); } protected override void OnElementChanged(ElementChangedEventArgs e) { base.OnElementChanged(e); if (e.OldElement != null) e.OldElement.Toggled -= HandleToggled; if (e.NewElement != null) { if (Control == null) { var aswitch = CreateNativeControl(); aswitch.SetOnCheckedChangeListener(this); SetNativeControl(aswitch); } else UpdateEnabled(); // Normally set by SetNativeControl, but not when the Control is reused. e.NewElement.Toggled += HandleToggled; Control.Checked = e.NewElement.IsToggled; } } void HandleToggled(object sender, EventArgs e) { Control.Checked = Element.IsToggled; } void UpdateEnabled() { Control.Enabled = Element.IsEnabled; } } }