Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
773 views
in Technique[技术] by (71.8m points)

c# - Change button text color in disabled button (Xamarin.Forms)

I need to change the text color of a button when it is disabled, I have created a custom renderer for iOS and one for Android. The iOS worked perfectly, since the android does not change the color, I have also created triggers via styles and also does not solve.

How to make color swap work for Xamarin.Forms?

Android Renderer:

[assembly: ExportRenderer(typeof(Button), typeof(MyButtonRenderer))]
namespace xxxxxx.Droid.Renderers
{
    public class MyButtonRenderer : ButtonRenderer
    {
        protected override void OnElementChanged(ElementChangedEventArgs<Button> e)
        {
            base.OnElementChanged(e);

            if (Control != null)
                Control.SetTextColor(Color.White.ToAndroid());

            if (e != null)
            {
                e.NewElement.TextColor = Color.White;
                e.OldElement.TextColor = Color.White;
            }
        }
    }
}

This state change is changed according to the CanExecute of my commands, this would be the default style applied.

Neither of these ways solves

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Answer

0 votes
by (71.8m points)

For Android:

[assembly: ExportRenderer(typeof(Button), typeof(MyButtonRenderer))]
namespace Forms.Droid.Renderers
{
    public class MyButtonRenderer : ButtonRenderer
    {
        public MyButtonRenderer(Context context) : base(context) { }

        protected override void OnElementChanged(ElementChangedEventArgs<Button> args)
        {
            base.OnElementChanged(args);
            if (Control != null) SetColors();
        }

        protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs args)
        {
            base.OnElementPropertyChanged(sender, args);
            if (args.PropertyName == nameof(Button.IsEnabled)) SetColors();
        }

        private void SetColors()
        {
            Control.SetTextColor(Element.IsEnabled ? Element.TextColor.ToAndroid() : Android.Graphics.Color.Gray);
            Control.SetBackgroundColor(Element.IsEnabled ? Element.BackgroundColor.ToAndroid() : Android.Graphics.Color.DarkGray);
        }
    }
}

For iOS:

[assembly: ExportRenderer(typeof(Button), typeof(MyButtonRenderer))]
namespace Forms.iOS.Renderers
{
    public class MyButtonRenderer : ButtonRenderer
    {
        protected override void OnElementChanged(ElementChangedEventArgs<Button> args)
        {
            base.OnElementChanged(args);
            if (Control != null) SetColors();
        }

        protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs args)
        {
            base.OnElementPropertyChanged(sender, args);
            if (args.PropertyName == nameof(Button.IsEnabled)) SetColors();
        }

        private void SetColors()
        {
            Control.SetTitleColor(Element.IsEnabled ? Element.TextColor.ToUIColor() : UIColor.Gray, Element.IsEnabled ? UIControlState.Normal : UIControlState.Disabled);
            Control.BackgroundColor = Element.IsEnabled ? Element.BackgroundColor.ToUIColor() : UIColor.DarkGray;
        }
    }
}

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome to OStack Knowledge Sharing Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...