Dependency Service: set accessibility focus to other control after a button click

Raj 1 Reputation point
2021-11-16T19:05:10.227+00:00

My issue is similar to below question :

https://social.msdn.microsoft.com/Forums/en-US/ef62f3b6-4599-4853-a274-a21238c02225/dependency-service-set-accessibility-focus-after-a-button-click?forum=xamarinforms

Unable to move the focus to other control when a button is clicked. Below is the code

class OnViewVisibilityService : IOnViewVisibilityService
    {
        public void getVisibileView(Xamarin.Forms.View view)
        {
            var vRenderer = Platform.CreateRendererWithContext(view, Android.App.Application.Context);
            var view1 = vRenderer.View;
            view1.SendAccessibilityEvent(Android.Views.Accessibility.EventTypes.ViewFocused);

        }
    }

----------- calling Dependency service in a button tap event -------------------

DependencyService.Get<IOnViewVisibilityService>().getVisibileView(PageHeaderLabel);
//PageHeaderLabel is Xamarin form Label

Could anyone look into it and let me what am missing?

Xamarin
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A Microsoft open-source app platform for building Android and iOS apps with .NET and C#.
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  1. Leon Lu (Shanghai Wicresoft Co,.Ltd.) 41,666 Reputation points Microsoft Employee
    2021-11-17T03:15:51.557+00:00

    Hello,​

    Welcome to our Microsoft Q&A platform!

    I find use Dependence Service cannot get the TextView, So I achive it in the Custom Renderer. we should create a custom Label. Create a method called GetAccessibilityForLabel,

       public class MyLabel:Label  
           {  
               public event EventHandler GetAccessibility;  
               public void GetAccessibilityForLabel() {  
         
                   if (GetAccessibility != null)  
                   {  
                       GetAccessibility(this, EventArgs.Empty);  
                   }  
         
               }  
         
           }  
    

    then we can call it in the button click event,

       private void Button_Clicked(object sender, EventArgs e)  
               {  
          
                   myLabel.GetAccessibilityForLabel();  
                 
               }  
    

    Then we can achieve this get Accessibility in the custom renderer with textView.SendAccessibilityEvent(EventTypes.ViewHoverEnter);.

       namespace App150.Droid  
       {  
           class MyLabelRenderer : LabelRenderer  
           {  
               public MyLabelRenderer(Context context) : base(context)  
               {  
               }  
               TextView textView;  
               MyLabel myLabel;  
               protected override void OnElementChanged(ElementChangedEventArgs<Label> e)  
               {  
                   base.OnElementChanged(e);  
                   if (e.NewElement != null)  
                   {  
                       textView = Control as TextView;  
                       myLabel = e.NewElement as MyLabel;  
                       myLabel.GetAccessibility += OnAccessibilityRequested;  
                   }  
                   if (e.OldElement != null)  
                   {  
                       myLabel.GetAccessibility -= OnAccessibilityRequested;  
                   }      
                }  
         
               private void OnAccessibilityRequested(object sender, EventArgs e)  
               {  
                       Device.BeginInvokeOnMainThread(() => {                  
                           textView.SendAccessibilityEvent(EventTypes.ViewHoverEnter);  
                       });  
                    
               }  
           }  
       }  
    

    Best Regards,

    Leon Lu


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