Question

I am using MonoTouch.Dialog to create a settings-like page. The linq below creates a set of RootElements, each with one section that has a set of RadioEventElements (a subclass of RadioElement that I created in order to add an OnSelected event).

        // initialize other phone settings by creating a radio element list for each phone setting
        var elements = (from ps in PhoneSettings.Settings.Keys select (Element) new RootElement(ps, new RadioGroup(null, 0))).ToList();

        // loop through the root elements we just created and create their substructure
        foreach (RootElement rootElement in elements)
        {
            rootElement.Add(new Section()
            {
                (from val in PhoneSettings.Settings[rootElement.Caption].Values select (Element) new RadioEventElement(val.Name)).ToList()
            });
            // ...
        }       

One of the settings I implement is a “Theme” – which currently is simply a background color for the various screens in the app. I can style every one of the pages correctly by setting the TableView.BackgroundColor property to the desired color… Except for new DialogViewControllers that are automatically created and pushed by the parent DialogViewController when it navigates into a radio group.

Is there any way to style (or at least set the background color) of this child DialogViewController?

Answer 1

I need to use the assembly browser more before asking easy questions 🙂

Fortunately the RootElement has a virtual method called PrepareDialogViewController for what appears to be exactly this purpose. All I had to do is create a simple subclass of RootElement and override this method to get my desired behavior.

public class ThemedRootElement : RootElement 
{    
    public ThemedRootElement(string caption) : base (caption)
    {
    }

    public ThemedRootElement(string caption, Func<RootElement, UIViewController> createOnSelected) : base (caption, createOnSelected)
    {
    }

    public ThemedRootElement(string caption, int section, int element) : base (caption, section, element)
    {
    }

    public ThemedRootElement(string caption, Group group) : base (caption, group)
    {
    }

    protected override void PrepareDialogViewController(UIViewController dvc)
    {
        dvc.View.BackgroundColor = UIColorHelper.FromString(App.ViewModel.Theme.PageBackground);
        base.PrepareDialogViewController(dvc);
    }
}

Hopefully this helps save someone out there a litte time…