檢查lablgtk2中是否按下了「control」

Question

我在lablgtk2中遇到了很多test_modifier方法的問題。我可以測試Shift，但這對我的目的不是很有用。每當我測試控制和另一個鍵被按下時，什麼都不會發生。我也試過這個：

view#event#connect#key_press ~callback:(fun ev -> 
    let m = GdkEvent.Key.state ev in 
    let k = GdkEvent.Key.keyval ev in 
     if (m = [`CONTROL] && k = _F) then 
      ... 

它工作了一段時間，然後停止。上面的代碼有什麼問題，它不會做任何事情？如何正確測試lablgtk2中的Control鍵？

Answer 1

一次可以有幾個修飾符，因此與[`CONTROL]比較無效。

let pr fmt = Printf.ksprintf print_endline fmt 

let button label packing f = 
    let b = GButton.button ~label ~packing() in 
    let _ = b#connect#clicked ~callback:f in 
() 

let() = 
    let locale = GtkMain.Main.init() in 
    let window = GWindow.window ~title:"test" ~border_width:10() in 
    let _ = window#connect#destroy ~callback:GMain.quit in 
    let mainbox = GPack.vbox ~packing:window#add() in 
    button "quit" mainbox#pack window#destroy; 

    let _ = window#event#connect#key_press ~callback:begin fun ev -> 
    let m = GdkEvent.Key.state ev in 
    let k = GdkEvent.Key.keyval ev in 
    if (List.mem `CONTROL m && k = GdkKeysyms._F) then pr "WOO HOO"; 
    if (List.mem `CONTROL m && k = GdkKeysyms._f) then pr "woo hoo"; 
    false 
    end in 
    window#event#add [`KEY_PRESS]; 
    window#show(); 
    GMain.main()