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c# - How to create a progress bar with rounded corners in iOS using Xamarin.Forms

I used inputs from this SO Question to create a custom progress-bar with rounded corners for the Android platform using the Drawable. But the I'm not able to create the same output for the iOS.

Given below is how it looks on Android. Android Sample

How can I create the same effect in the iOS as well?

See Question&Answers more detail:os

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There are a number of ways to do this, I prefer using the CALayer of a UIView and adding a CAShapeLayer that draws the "progress bar".

UIView ProgressBar Example:

enter image description here

public class ProgressView : UIView
{
    CAShapeLayer progressLayer;
    UILabel label;

    public ProgressView() { Setup(); }
    public ProgressView(Foundation.NSCoder coder) : base(coder) { Setup(); }
    public ProgressView(Foundation.NSObjectFlag t) : base(t) { Setup(); }
    public ProgressView(IntPtr handle) : base(handle) { }
    public ProgressView(CGRect frame) : base(frame) { Setup(); }

    void Setup()
    {
        BackgroundColor = UIColor.Clear;

        Layer.CornerRadius = 25;
        Layer.BorderWidth = 10;
        Layer.BorderColor = UIColor.Blue.CGColor;
        Layer.BackgroundColor = UIColor.Cyan.CGColor;

        progressLayer = new CAShapeLayer()
        {
            FillColor = UIColor.Red.CGColor,
            Frame = Bounds
        };
        Layer.AddSublayer(progressLayer);

        label = new UILabel(Bounds)
        {
            TextAlignment = UITextAlignment.Center,
            TextColor = UIColor.White,
            BackgroundColor = UIColor.Clear,
            Font = UIFont.FromName("ChalkboardSE-Bold", 20)
        };
        InsertSubview(label, 100);
    }

    double complete;
    public double Complete
    {
        get { return complete; }
        set { complete = value; label.Text = $"{value * 100} %"; SetNeedsDisplay(); }
    }

    public override void Draw(CGRect rect)
    {
        base.Draw(rect);
        var progressWidth = (rect.Width - (Layer.BorderWidth * 2)) * complete;
        var progressRect = new CGRect(rect.X + Layer.BorderWidth, rect.Y + Layer.BorderWidth, progressWidth, (rect.Height - Layer.BorderWidth * 2));
        progressLayer.Path = UIBezierPath.FromRoundedRect(progressRect, 25).CGPath;
    }
}

Usage Example:

var progressView = new ProgressView(new CGRect(50, 50, 300, 50));
Add(progressView);
DispatchQueue.MainQueue.DispatchAsync(async () =>
{
    while (progressView.Complete <= 1)
    {
        InvokeOnMainThread(() => progressView.Complete += 0.05);
        await Task.Delay(1000);
    }
});

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