examples/reference/csharp/ui/src/focus_main.cs

using System;

public class Example
{
    public static void FocusChangedCb(object sender, EventArgs e)
    {
        Console.WriteLine($"Focus for object {((efl.IText)sender).GetText()} changed to {((efl.ui.IWidget)sender).GetFocus()}");
    }

#if WIN32
    [STAThreadAttribute()]
#endif
    public static void Main()
    {
        // Initialize EFL and all UI components
        efl.All.Init(efl.Components.Ui);

        // Create a window and initialize it
        var win = new efl.ui.Win(null, (efl.ui.IWin ewin) => {
            ewin.SetWinType(efl.ui.Win_Type.Basic);
            ewin.SetText("Focus example");
            ewin.SetAutohide(true);
            ewin.HideEvt += (object sender, EventArgs e) => {
                // Exit the EFL main loop
                efl.ui.Config.Exit();
            };
        });

        // Create the main box container
        var vbox = new efl.ui.Box(win, (efl.ui.IBox ebox) => {
          ebox.SetHintMin(new eina.Size2D(360, 240));
          win.SetContent(ebox);
        });

        // Create some check boxes
        efl.ui.ICheck first_checkbox = null;
        for (int i = 0; i< 5; i++) {
          var checkbox = new efl.ui.Check(vbox, (efl.ui.ICheck echeck) => {
            echeck.SetText("Check " + i);
            echeck.SetHintAlign(0.5, 0.5);
            echeck.FocusChangedEvt += FocusChangedCb;
            vbox.DoPack(echeck);
          });
          if (i == 0) first_checkbox = checkbox;
        };

        // Create an horizontal box to contain the two buttons
        var hbox = new efl.ui.Box(vbox, (efl.ui.IBox ebox) => {
          ebox.SetDirection(efl.ui.Dir.Horizontal);
          vbox.DoPack(ebox);
        });

        // Create a "Focus Mover" button
        new efl.ui.Button(hbox, (efl.ui.IButton ebutton) => {
          ebutton.SetText("Focus mover");
          ebutton.FocusChangedEvt += FocusChangedCb;
          ebutton.ClickedEvt += (object sender, EventArgs e) => {
            Console.WriteLine("Clicked Focus Mover");
            // Manually transfer focus to the first check box
            efl.ui.focus.Util.Focus(first_checkbox);
          };
          hbox.DoPack(ebutton);
        });

        // Create a Quit button
        new efl.ui.Button(hbox, (efl.ui.IButton ebutton) => {
          ebutton.SetText("Quit");
          ebutton.FocusChangedEvt += FocusChangedCb;
          ebutton.ClickedEvt += (object sender, EventArgs e) => {
            Console.WriteLine("Clicked Quit");
            efl.ui.Config.Exit();
          };
          hbox.DoPack(ebutton);
          // Set focus on this widget and show the focus highlight
          ebutton.SetFocusHighlightEnabled(true);
        });

        // Start the EFL main loop
        efl.ui.Config.Run();

        // Shutdown EFL
        efl.All.Shutdown();
    }
}