Xamarin.Forms。 安卓。 无法隐藏键盘

Question

When my Entry control get focus a virtual keyboard appears. I need to hide keyboard and show it only when user explicitly calls. I tried to use InputMethodManager to hide keyboard, but after calling the HideSoftInputFromWindow(...) method, keyboard still remains on screen. ToggleSoftInputFromWindow(...) method also does not work.

.NET Standard project:

public partial class App : Application
{
    public IKeyboardService KeyboardService { get; set; }

    public App()
    {
        InitializeComponent();
        MainPage = new MainPage( new MainViewModel() );
    }
}

public partial class CustomEntry
{
    public CustomEntry()
    {
        InitializeComponent();
        Focused += OnCustomEntryFocused;
    }

    private void OnCustomEntryFocused( object sender, FocusEventArgs e )
    {
        ( (App)App.Current ).KeyboardService.HideKeyboard();
    }
}

public interface IKeyboardService
{
    void HideKeyboard();
}

Android project:

public class KeyboardService : IKeyboardService
{
    public void HideKeyboard()
    {
        var activity = MainActivity.Instance;
        var imm = activity.GetSystemService( Context.InputMethodService ) as InputMethodManager;
        if ( imm != null )
        {
            var token = activity.CurrentFocus?.WindowToken;
            imm.HideSoftInputFromWindow( token, HideSoftInputFlags.NotAlways );
            //imm.ToggleSoftInputFromWindow( token, ShowSoftInputFlags.None, HideSoftInputFlags.NotAlways );
        }
    }
}

How can I hide keyboard?

Answer 1

You can hide the keyboard programmatically in Xamarin.Forms by toggling IsEnabled on the Entry

public class CustomEntry
{
    public CustomEntry()
    {
        InitializeComponent();
        Focused += OnCustomEntryFocused;
    }

    private void OnCustomEntryFocused(object sender, FocusEventArgs e)   
    {
        var entry = (Entry)sender;

        entry.IsEnabled = false;
        entry.IsEnabled = true;
    }
}

Answer 2

One method is like Brandon Minnick said above,use the IsEnable property to disable its focus.

here is another method,that you should create a custom renderer in your Android project:

[assembly: ExportRenderer(typeof(CustomEntry), typeof(MyEntryRenderer))]
namespace EntryCa.Droid
{
  class MyEntryRenderer:EntryRenderer
  {
    public MyEntryRenderer(Context context) : base(context)
    {

    }
    protected override void OnElementChanged(ElementChangedEventArgs<Entry> e)
    {
        base.OnElementChanged(e);

        if (Control != null)
        {
            // do whatever you want to the UITextField here!
            Control.InputType = Android.Text.InputTypes.Null;
        }
    }
  }
}

then in your PLC project :

public partial class CustomEntry :Entry
{

}

in your page.xaml :

<local:CustomEntry Placeholder="hi" ></local:CustomEntry>

you will see when you fouse the Entry,it will not popup the keyboard.

Answer 3

If you want to hide the keyboard when activity start , in your activity add this:

WindowSoftInputMode = Android.Views.SoftInput.StateAlwaysHidden

[Activity(Label = "MainActivity", WindowSoftInputMode = Android.Views.SoftInput.StateAlwaysHidden)]

    public class MainActivity : Activity
    {  }

To hide the keyboard programmatically use this function:

private void DismissKeyboard()
        {
            var view = CurrentFocus;
            if (view != null)
            {
                var imm = (InputMethodManager)GetSystemService(InputMethodService);
                imm.HideSoftInputFromWindow(view.WindowToken, 0);
            }
        }

Or this function:

private void DismissKeyboard2()
        {
            var currentFocus = this.CurrentFocus;
            if (currentFocus != null)
            {
                InputMethodManager inputMethodManager = (InputMethodManager)this.GetSystemService(Context.InputMethodService);
                inputMethodManager.HideSoftInputFromWindow(currentFocus.WindowToken, HideSoftInputFlags.None);
            }

        }

Or use theme together like:

myEditText.FocusChange += (object sender, View.FocusChangeEventArgs e) =>
            {

                DismissKeyboard();
                DismissKeyboard2();
            };