UIProgressView disappear or doesn't scale when device rotate - ios

Question

I am using Xamarin.IOS, I have UIprogressView inside a UIScrollView with two buttons as well.
I am setting the UIprogressView frame by code in ViewWillLayoutSubviews method:
CGRect newFrame;
newFrame.Width = MyScrollView.Frame.Width / 2;
newFrame.Location = new CGPoint(0, NextButton.Frame.Y);
MyProgressView.Frame = newFrame;
MyProgressView.Transform = CGAffineTransform.MakeScale(1, 20f);
MyProgressView.TrackTintColor = CustomColors.CustomColors.GetColor(CustomColors.CustomColors.ColorGray);
MyProgressView.ProgressTintColor = CustomColors.CustomColors.GetColor(CustomColors.CustomColors.ColorBlue);
The problem is when I rotate the device from portrait to landscape, only the progressview will disappear. Meanwhile the next button is there and both progress view and next button have same Y!.
If I stopped using MyProgressView.ProgressTintColor I can see the progress view after rotation but it is not scaled.
Any idea how to fix it?
This is the UIProgressView I am talking about:

Answer 1

Create this UIProgressView file in your Helper folder
LoadingOverlay.cs
public class LoadingOverlay : UIView
{
// control declarations
UIActivityIndicatorView activitySpinner;
UILabel loadingLabel;
public LoadingOverlay(CGRect frame) : base(frame)
{
// configurable bits
BackgroundColor = UIColor.Black;
Alpha = 0.75f;
AutoresizingMask = UIViewAutoresizing.All;
nfloat labelHeight = 22;
nfloat labelWidth = Frame.Width - 20;
// derive the center x and y
nfloat centerX = Frame.Width / 2;
nfloat centerY = Frame.Height / 2;
// create the activity spinner, center it horizontall and put it 5 points above center x
activitySpinner = new UIActivityIndicatorView(UIActivityIndicatorViewStyle.WhiteLarge);
activitySpinner.Frame = new CGRect(
centerX - (activitySpinner.Frame.Width / 2),
centerY - activitySpinner.Frame.Height - 20,
activitySpinner.Frame.Width,
activitySpinner.Frame.Height);
activitySpinner.AutoresizingMask = UIViewAutoresizing.All;
AddSubview(activitySpinner);
activitySpinner.StartAnimating();
// create and configure the "Loading Data" label
loadingLabel = new UILabel(new CGRect(
centerX - (labelWidth / 2),
centerY + 20,
labelWidth,
labelHeight
));
loadingLabel.BackgroundColor = UIColor.Clear;
loadingLabel.TextColor = UIColor.White;
loadingLabel.Text = "Loading Data...";
loadingLabel.TextAlignment = UITextAlignment.Center;
loadingLabel.AutoresizingMask = UIViewAutoresizing.All;
AddSubview(loadingLabel);
}
/// <summary>
/// Fades out the control and then removes it from the super view
/// </summary>
public void Hide()
{
UIView.Animate(
0.5, // duration
() => { Alpha = 0; },
() => { RemoveFromSuperview(); }
);
}
}
and Use this way
to show the loading
var loadingOverlay = new LoadingOverlay(UIScreen.MainScreen.Bounds);
View.Add(loadingOverlay);
and to hide it
loadingOverlay.Hide();

Answer 2

I fixed it by re-scale it at every rotate:
public override void WillAnimateRotation(UIInterfaceOrientation toInterfaceOrientation, double duration)
{
progressView.Transform = CGAffineTransform.Scale(progressView.Transform,1, 20f);
}