Is there a way to dynamically set the background for EntryCell in iOS depending upon Light Mode and DarkMode?

Question

I am trying to support dark mode and light mode in my app. It works perfectly except with the EntryCell. Seems like it has its own background and I tried dynamically set the entrycell background but that did not work. Its not reacting with dynamic resource. and I am out of luck trying to dynamically set the background color for EntryCell. Right now I can only set to Black or White background. Any ideas? Here's my:

This is my page renderer


[assembly: ExportRenderer(typeof(ContentPage), typeof(Mobile.Base.iOS.PageRenderer))]
namespace Mobile.Base.iOS
{

    public class PageRenderer : Xamarin.Forms.Platform.iOS.PageRenderer
    {
        protected override void OnElementChanged(VisualElementChangedEventArgs e)
        {
            base.OnElementChanged(e);

            if (e.OldElement != null || Element == null)
            {
                return;
            }

            try
            {
                SetAppTheme();
            }
            catch (Exception ex)
            {
                Console.WriteLine($"\t\t\tERROR: {ex.Message}");
            }
        }

        public override void TraitCollectionDidChange(UITraitCollection previousTraitCollection)
        {
            base.TraitCollectionDidChange(previousTraitCollection);
            Console.WriteLine($"TraitCollectionDidChange: {TraitCollection.UserInterfaceStyle} != {previousTraitCollection.UserInterfaceStyle}");

            if (previousTraitCollection != null && TraitCollection.UserInterfaceStyle != previousTraitCollection.UserInterfaceStyle)
            {
                SetAppTheme();
            }


        }

        private void SetAppTheme()
        {
            if (TraitCollection.UserInterfaceStyle == UIUserInterfaceStyle.Dark)
            {
                if (App.AppTheme == "dark")
                    return;

                //Add a Check for App Theme since this is called even when not changed really
                App.Current.Resources = new DarkTheme();

                App.AppTheme = "dark";
            }
            else
            {
                if (App.AppTheme != "dark")
                    return;
                App.Current.Resources = new LightTheme();

                App.AppTheme = "light";
            }
        }

    }
}

This is my custom entry cell renderer


namespace Mobile.Base.iOS
{
    public class customEntryCell : EntryCellRenderer
    {
        public override UITableViewCell GetCell(Cell item, UITableViewCell reusableCell, UITableView tv)
        {
            var nativeCell = (EntryCell)item;
            var cell = base.GetCell(nativeCell, reusableCell, tv);
            ((UITextField)cell.Subviews[0].Subviews[0]).BackgroundColor = UIColor.White;
            return cell;
        }
    }
}

Seems like I found a work around on that, setting BackGroundColor to Transparent for TableView made it worked. But if you find other solution let me know — Bigyan Devkota
How did you dynamically set the entrycell backgroundColor? You should change the backgroundColor in custom renderer. — Jack Hua

Jack Hua Jack Hua · Accepted Answer · 2020-01-08T02:36:48

You can change the Entrycell's backgroundColor by changing cell.ContentView.BackgroundColor in custom renderer:

public class myEntryCelliOSCellRenderer : EntryCellRenderer
{

    public override UITableViewCell GetCell(Cell item, UITableViewCell reusableCell, UITableView tv)
    {
        var nativeCell = (EntryCell)item;

        var cell = base.GetCell(nativeCell, reusableCell, tv);

        ((UITextField)cell.Subviews[0].Subviews[0]).TextColor = UIColor.Orange;
        ((UITextField)cell.Subviews[0].Subviews[0]).BackgroundColor = UIColor.Green;

        //Change the entrycell backgroundColor
        cell.ContentView.BackgroundColor = UIColor.Red;

        return cell;
    }
}

Here is the source code of EntryCellRenderer you can check.

Is there a way to dynamically set the background for EntryCell in iOS depending upon Light Mode and DarkMode?

1 Answers