Answers

• AndrewMobile USMember ✭✭✭✭

  May 2015 edited May 2015 Accepted Answer

  @MichaelRumpler
  long story short, it's tricky.

  Even on native without Xamarin Forms, changing the master view width on a UISplitViewController is not easy because the properties for changing it are only available with iOS8.
  For iOS7 it's tricky, people are calling private methods or subclass UISplitViewController and layout the views in viewDidLayoutSubviews.

  Now, with XF, there's more work. If you just want to support iOS8, you could derive from TabletMasterDetailRenderer, and just call those properties for iOS8. For iOS7, you would have to do the same thing as in native.

  Hope this helps or answers your question

  5
• AndrewMobile USMember ✭✭✭✭

  May 2015

  I edited my answer.

  0
• MichaelRumpler ATMember ✭✭✭✭✭

  May 2015 edited May 2015

  Thanks @AndreiNitescu
  Could you reference something where this is explained? Which properties are you talking about?
  But keep in mind, I don't want to change the width of the Master, but only the Detail.
  As it happens, I already do subclass the TabletMasterDetailRenderer, so I could just add some more there.

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• AndrewMobile USMember ✭✭✭✭

  May 2015 edited May 2015 Accepted Answer

  @MichaelRumpler
  googling a bit you gonna find different solutions, here's what I get first
  http://stackoverflow.com/questions/2949067/change-the-width-of-master-in-uisplitviewcontroller

  and these are the properties
  https://developer.apple.com/library/ios/documentation/UIKit/Reference/UISplitViewController_class/#//apple_ref/occ/instp/UISplitViewController/maximumPrimaryColumnWidth

  5
• AndrewMobile USMember ✭✭✭✭

  May 2015

  @MichaelRumpler I'm thinking that you could dynamically switch from popover to side by side when master is visible. but you need to make master disappear on swipe like in popover mode

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• AndrewMobile USMember ✭✭✭✭

  May 2015

  @MichaelRumpler I wonder how difficult would it be to use MGSplitViewController instead. It allows you to change widths easily

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• MichaelRumpler ATMember ✭✭✭✭✭

  May 2015

  I'll see how far I'll come with jrc's answer on SO and the maximumPrimaryColumnWidth. If that won't work, I'll have a look at the MGSplitViewController too. I'll let you know.
  Thank you!

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• MichaelRumpler ATMember ✭✭✭✭✭

  May 2015

  I got it working, but with a limitation due to a bug in Xamarin.Forms. Here is my complete TabletMasterDetailRenderer:

  using System;
  using System.Reflection;
  using CoreGraphics;
  using UIKit;
  using Xamarin.Forms;
  
  [assembly: ExportRenderer(
      typeof(MasterDetailPage),
      typeof(MyNamespace.iOS.Renderers.TabletMasterDetailRenderer),
      UIUserInterfaceIdiom.Pad)]
  
  namespace MyNamespace.iOS.Renderers
  {
      public class TabletMasterDetailRenderer : Xamarin.Forms.Platform.iOS.TabletMasterDetailRenderer
      {
          private readonly nfloat SplitterWidth = (nfloat)0.5;
  
          protected override void OnElementChanged(Xamarin.Forms.Platform.iOS.VisualElementChangedEventArgs e)
          {
              base.OnElementChanged(e);
  
              if (e.OldElement != null)
                  ((MasterDetailPage)e.OldElement).IsPresentedChanged -= onIsPresentedChanged;
              if (e.NewElement != null)
                  ((MasterDetailPage)e.NewElement).IsPresentedChanged += onIsPresentedChanged;
          }
  
          protected override void Dispose(bool disposing)
          {
              base.Dispose(disposing);
  
              if (Element != null)
                  ((MasterDetailPage)Element).IsPresentedChanged -= onIsPresentedChanged;
          }
  
          // Workaround to preserve delimiter color. It is set to white (hardcoded) by Xamarins ViewDidLoad method.
          public override void ViewDidLoad()
          {
              var color = this.View.BackgroundColor;
              base.ViewDidLoad();
              this.View.BackgroundColor = color;
          }
  
          private void onIsPresentedChanged(object sender, EventArgs e)
          {
              adjustDetailWidth();
          }
  
          public override void ViewDidLayoutSubviews()
          {
              base.ViewDidLayoutSubviews();
  
              adjustDetailWidth();
          }
  
          private void adjustDetailWidth()
          {
              var mainWidth = View.Frame.Width;
              var masterWidth = ViewControllers[0].View.Frame.Width;
              var detailFrame = ViewControllers[1].View.Frame;
              var masterVisible = ((MasterDetailPage)Element).IsPresented;
  
              nfloat desiredX = 0;
              nfloat desiredWidth = mainWidth;
              if (masterVisible)
              {
                  desiredX = masterWidth + SplitterWidth;
                  desiredWidth = mainWidth - desiredX;
              }
  
              if (desiredX != detailFrame.X || desiredWidth != detailFrame.Width)
              {
                  SetDetailBounds(new Rectangle(desiredX, detailFrame.Y, desiredWidth, detailFrame.Height));
              }
          }
  
          PropertyInfo detailBoundsProperty;
  
          private void SetDetailBounds(Rectangle rectangle)
          {
              // unfortunately, this doesnt animate the width, but I can live with that
              // (width is set at once, X is animated)
              UIView.Animate(
                  0.2,
                  () => ViewControllers[1].View.Frame = new CGRect(rectangle.X, rectangle.Y, rectangle.Width, rectangle.Height)
              );
  
              // must set internal DetailBounds because base.ViewDidLayoutSubviews always sets X to 0
              if (detailBoundsProperty == null)
                  detailBoundsProperty = this.Element.GetType().GetProperty("DetailBounds", BindingFlags.NonPublic | BindingFlags.Instance);
              if (detailBoundsProperty != null && detailBoundsProperty.CanWrite)
                  detailBoundsProperty.SetValue(this.Element, rectangle);
          }
      }
  }
  

  The problem is, that the IsPresentedChanged event is not always raised. When the Master is visible and you rotate your device, then it is not raised anymore. I created bug 30353 for that.

  I tried using the Master.Appearing/Disappearing events instead, but they are also not raised anymore after the bug explained above got triggered. Moreover they are only raised after the Master slided in/out, but I need to start the animation for the Detail position when it starts.

  @ChrisKing from Xamarin already confirmed the bug, but he didn't change the status yet.

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• MichaelRumpler ATMember ✭✭✭✭✭

  May 2015

  @AndreiNitescu I just recognized some new problems which came up after I changed the MasterBehavior from Split to Popover. Whenever I tap something on the Detail page, the Master will be scrolled off. There is also always a "Navigation" link at the top left of the Detail page, even though the Master is visible. Both are not desired of course.

  Will I have to make the whole TabletMasterDetailRenderer new without inheriting from the existing?

  0