Hide StatusBar for specific ContentPage

问题

I'm creating an app where I want to hide the statusbar on a specific page. In my example it's a ContentPage. I found several samples where the info.plist is used to hide it, but I only want it for a specific page, is it possible? It's easy to hide the navigationbar with NavigationPage.SetHasNavigationBar, but statusbar seems a bit different.

回答1:

As far as I know, Xamarin doesn't provide this functionality through Xamarin.Forms classes. You will need to implement it in each platform specific project.

However, this should be fairly easy as you can use a DependencyService to handle this.

Here is a quick implementation...

App.cs

public App()
{
    var layout = new StackLayout
    {
        VerticalOptions = LayoutOptions.Center,
        Children =
        {
            new Label
            {
                XAlign = TextAlignment.Center,
                Text = "Welcome to Xamarin Forms!"
            }
        }
    };

    var button = new Button
    {
        Text = "Click Me"
    };
    button.Clicked += (object sender, EventArgs e) => 
        {
            if (_isHidden)
            {
                // show
                DependencyService.Get<IStatusBar>().ShowStatusBar();
            }
            else
            {
                // hide
                DependencyService.Get<IStatusBar>().HideStatusBar();
            }

            _isHidden = !_isHidden;
        };

    layout.Children.Add(button);

    // The root page of your application
    MainPage = new ContentPage
    {
        Content = layout
    };
}

IStatusBar.cs

public interface IStatusBar
{
    void HideStatusBar();
    void ShowStatusBar();
}

AndroidImplementation

[assembly: Xamarin.Forms.Dependency(typeof(StatusBarImplementation))]
namespace MyXamarinApp.Droid
{
    public class StatusBarImplementation : IStatusBar
    {
        public StatusBarImplementation()
        {
        }

        WindowManagerFlags _originalFlags;

        #region IStatusBar implementation

        public void HideStatusBar()
        {
            var activity = (Activity)Forms.Context;
            var attrs = activity.Window.Attributes;
            _originalFlags = attrs.Flags;
            attrs.Flags |= Android.Views.WindowManagerFlags.Fullscreen;
            activity.Window.Attributes = attrs;
        }

        public void ShowStatusBar()
        {
            var activity = (Activity)Forms.Context;
            var attrs = activity.Window.Attributes;
            attrs.Flags = _originalFlags;
            activity.Window.Attributes = attrs;
        }

        #endregion
    }
}

iOSImplementation

[assembly: Xamarin.Forms.Dependency(typeof(StatusBarImplementation))]
namespace MyXamarinApp.iOS
{
    public class StatusBarImplementation : IStatusBar
    {
        public StatusBarImplementation()
        {
        }

        #region IStatusBar implementation

        public void HideStatusBar()
        {
            UIApplication.SharedApplication.StatusBarHidden = true;
        }

        public void ShowStatusBar()
        {
            UIApplication.SharedApplication.StatusBarHidden = false;
        }

        #endregion
    }
}

The idea being that you call the DependencyService implementation to hide the status bar when you need it hidden on a specific ContentPage. You also may need to show it again after hiding(not really sure).

NOTE: For iOS, you need to update the Info.plist file to allow the application to change the status bar visibility.

回答2:

You could use a PageRenderer for this. Here is an example:

public class NoStatusBarPageRenderer : PageRenderer
{
    public NoStatusBarPageRenderer()
    {
    }

    public override void ViewWillAppear(bool animated)
    {
        UIApplication.SharedApplication.SetStatusBarHidden(true, UIStatusBarAnimation.Fade);

        base.ViewWillAppear(animated);
    }

    public override void ViewDidDisappear(bool animated)
    {
        UIApplication.SharedApplication.SetStatusBarHidden(false, UIStatusBarAnimation.Fade);

        base.ViewDidDisappear(animated);
    }
}

Then, for each page that you want to have the status bar hidden, add an attribute to use this renderer on that page.

[assembly: ExportRenderer(typeof(MyContentPage), typeof(NoStatusBarPageRenderer))]

回答3:

protected override void OnCreate (Bundle bundle)
{
    base.OnCreate (bundle);
    this.Window.ClearFlags(WindowManagerFlags.Fullscreen);
    SetContentView (Resource.Layout.Main);

    ...
}

来源：https://stackoverflow.com/questions/36449480/hide-statusbar-for-specific-contentpage