Cannot access the Navigation Bar in the second screen of the Navigation - uiviewcontroller

Question

I am developing an app using Xamarin.iOS. It will have a lot of screens that I cannot design using Main.StoryBoard, so I have to design every ViewController separately. Right now I have 2 screens: ViewController.cs and InProgress.cs. I have wrapt the ViewController.cs inside a NavigationController in Main.StoryBoard. Below is the code:
ViewController.cs (ViewDidLoad)
public override void ViewDidLoad ()
{
base.ViewDidLoad ();
//change the navigation bar controller
this.NavigationController.NavigationBar.BarTintColor = UIColor.FromRGB (26f / 255f, 56f / 255f, 100f / 255f);
this.NavigationController.NavigationBar.TitleTextAttributes = new UIStringAttributes()
{
ForegroundColor = UIColor.White
};
NavigationController.NavigationBar.BarStyle = UIBarStyle.Black;
//change the layout of collectionView Layout
//initialize the data
sectionCategories = new List<SectionCategory>();
sectionCategories.Add(new SectionCategory("Lajme", "http://www.ikub.al/media/iOS/lajme.jpg"));
......
sectionCategories.Add(new SectionCategory("Shtypi i dites", "http://www.ikub.al/media/HP/shtypi.jpg"));
sectionGrid.RegisterClassForCell(typeof(SectionViewCell), SectionViewCell.CellID);
sectionGrid.Source = new SectionViewSource (sectionCategories,this);
}
When I click an item of the sectionGrid it pushes a new ViewController in the stack.
var soonVC = new InProgress ("InProgress");
soonVC.Title = "InProgress";
owner.NavigationController.PushViewController(soonVC, true);
The InProgress screen has the a .cs file, a .desigener.cs file and .xib file like the following:
public partial class InProgress : UIViewController
{
String section;
public InProgress (String text) : base ("InProgress", null)
{
section = text;
}
public override void ViewDidLoad ()
{
base.ViewDidLoad ();
// Perform any additional setup after loading the view, typically from a nib.
}
public override void DidReceiveMemoryWarning ()
{
base.DidReceiveMemoryWarning ();
// Release any cached data, images, etc that aren't in use.
}
}
[Register ("InProgress")]
partial class InProgress
{
[Outlet]
[GeneratedCode ("iOS Designer", "1.0")]
UILabel labelComingSoon { get; set; }
void ReleaseDesignerOutlets ()
{
if (labelComingSoon != null) {
labelComingSoon.Dispose ();
labelComingSoon = null;
}
}
}
But I have 2 problems:
I have to access the navigation bar of InProgress screen in order to change the back item, navigation style, text color, back button text, add new item etc.
When I have designed the layout in .xib file I have the label in the center, but in reality it's not in the center of the screen because it does not take into consideration the height of the navigation bar, so some layout may be hidden under the NavigationBar.
I have tried some piece of code like
soonVC.NavigationItem.LeftBarButtonItem.Title = " dsf";
but it gives me a null object.
Any suggestion for both the problems.
InProgress.xib

Answer 1

In your InProgress class you can set the back button text like so :
public override void ViewDidLoad ()
{
base.ViewDidLoad ();
// Perform any additional setup after loading the view, typically from a nib.
UIBarButtonItem newBackButton = new UIBarButtonItem("dfs",UIBarButtonItemStyle.Plain, (sender,args) => NavigationController.PopViewController (true));
NavigationItem.SetLeftBarButtonItem (newBackButton, false);
// The line below will move the search bar below the nav bar
NavigationController.NavigationBar.Translucent = false;
}
As for the next question:
When I have designed the layout in Xib file I have the label in the
center, but in reality its not in the center of the screen because it
does not take into consideration the height of the navigation bar, so
some layout may be hidden under the Navigation bar.
Are you using Autolayout? All you need to do is add a constraint to center vertical and it should center in the view. Are you able to upload your xib? if you are not using Autolayout you will just have to adjust for the Navigation Controller.
UPDATE
If you set your navbar to not be translucent it will go below the nav bar. You can set this in the InProgress class or when you here in the storyboard:
I have also added the autolayout constraints to your xib to center your label here is the xib xml:
HTH.