public bool ShouldPushItem(UINavigationBar navigationBar, UINavigationItem item)
{
var v = navigationBar as NavigationBar;
if (v != null)
{
item.BackButton().AddTarget(this, new Selector("handleBackButton"), UIControlEvent.TouchUpInside);
item.BackButton().Image = v.BackButtonImage;
var c = item.LeftViews();
if (c != null)
{
c.Add(item.BackButton());
item.SetLeftViews(c);
}
else
{
item.SetLeftViews(new List <UIView>
{
item.BackButton()
});
}
v.layoutNavigationItem(item);
}
return(true);
}
/**
* Lays out the UINavigationItem.
* - Parameter item: A UINavigationItem to layout.
*/
internal void layoutNavigationItem(UINavigationItem item)
{
if (WillLayout)
{
prepareItem(item);
prepareTitleView(item);
var frame = item.TitleView.Frame;
frame.Location = CGPoint.Empty;
frame.Size = IntrinsicContentSize;
item.TitleView.Frame = frame;
var lc = 0;
var rc = 0;
var l = ((nfloat)(item.LeftViews().Count) * InterimSpace);
var r = ((nfloat)(item.RightViews().Count) * InterimSpace);
var p = this.Width() - l - r - ContentEdgeInsets.Left - ContentEdgeInsets.Right;
var columns = (int)(NMath.Ceiling(p / GridFactor));
item.TitleView.Grid().Begin();
item.TitleView.Grid().Views.Clear();
item.TitleView.Grid().Axis.Columns = columns;
foreach (var v in item.LeftViews())
{
if (v is UIButton)
{
((UIButton)v).ContentEdgeInsets = UIEdgeInsets.Zero;
((UIButton)v).TitleEdgeInsets = UIEdgeInsets.Zero;
}
v.SetWidth(v.IntrinsicContentSize.Width);
v.SizeToFit();
v.Grid().Columns = ((int)NMath.Ceiling(v.Width() / GridFactor)) + 2;
lc += v.Grid().Columns;
item.TitleView.Grid().Views.Add(v);
}
item.TitleView.Grid().Views.Add(item.ContentView());
foreach (var v in item.RightViews())
{
if (v is UIButton)
{
((UIButton)v).ContentEdgeInsets = UIEdgeInsets.Zero;
((UIButton)v).TitleEdgeInsets = UIEdgeInsets.Zero;
}
v.SetWidth(v.IntrinsicContentSize.Width);
v.SizeToFit();
v.Grid().Columns = ((int)NMath.Ceiling(v.Width() / GridFactor)) + 2;
rc += v.Grid().Columns;
item.TitleView.Grid().Views.Add(v);
}
item.ContentView().Grid().Begin();
if (item.ContentViewAlignment() == ContentViewAlignment.Center)
{
if (lc < rc)
{
item.ContentView().Grid().Columns = columns - 2 * rc;
item.ContentView().Grid().Offset.Columns = rc - lc;
}
else
{
item.ContentView().Grid().Columns = columns - 2 * lc;
item.ContentView().Grid().Offset.Columns = 0;
if (item.RightViews().Count > 0)
{
item.RightViews()[0].Grid().Offset.Columns = lc - rc;
}
}
}
else
{
item.ContentView().Grid().Columns = columns - lc - rc;
}
item.TitleView.Grid().InterimSpace = InterimSpace;
item.TitleView.Grid().ContentEdgeInsets = ContentEdgeInsets;
item.TitleView.Grid().Commit();
item.ContentView().Grid().Commit();
// contentView alignment.
if (!string.IsNullOrEmpty(item.Title()))
{
if (item.Titlelabel().Superview == null)
{
item.ContentView().AddSubview(item.Titlelabel());
}
item.Titlelabel().Frame = item.ContentView().Bounds;
}
else
{
item.Titlelabel().RemoveFromSuperview();
}
if (!string.IsNullOrEmpty(item.Detail()))
{
if (item.DetailLabel().Superview == null)
{
item.ContentView().AddSubview(item.DetailLabel());
}
if (item.Titlelabel().Superview == null)
{
item.DetailLabel().Frame = item.ContentView().Bounds;
}
else
{
item.Titlelabel().SizeToFit();
item.DetailLabel().SizeToFit();
nfloat diff = (item.ContentView().Frame.Height - item.Titlelabel().Frame.Height - item.DetailLabel().Frame.Height) / 2;
item.Titlelabel().SetHeight(item.Titlelabel().Height() + diff);
item.Titlelabel().SetWidth(item.ContentView().Width());
item.DetailLabel().SetHeight(item.DetailLabel().Height() + diff);
item.DetailLabel().SetWidth(item.ContentView().Width());
item.DetailLabel().SetY(item.Titlelabel().Height());
}
}
else
{
item.DetailLabel().RemoveFromSuperview();
}
}
}