java - MenuShortcut with multiple keys

Question

I'm trying a bit of Java AWT and I'm trying to create a menu shortcut that requires multiple keys to be pressed (for example Alt + Space + H).

I know that by doing this:

MenuItem item= new MenuItem("Text", new MenuShortcut(KeyEvent.VK_ALT));

I can create a shortcut requiring Ctrl + Alt to be pressed. But is there a way to add more keys?

标签： javaawt

Answer 1

From implementation of MenuShortcut class:

public MenuShortcut(int key) { ...
public MenuShortcut(int key, boolean useShiftModifier) { ...

This means that using MenuShortcut we can specify a maximum of three keys - Ctrl + Shift + Key.

MenuShortcut menushortcut_1 = new MenuShortcut(KeyEvent.VK_A, false); // Ctrl + A
MenuShortcut menushortcut_2 = new MenuShortcut(KeyEvent.VK_A, true);  // Ctrl + Shift + A

What you could do is extend the MenuShortcut class and extend the number of keys that are accepted (very basic example, will need a bit of work):

public class MyMenuShortcut extends MenuShortcut {

    int key1;
    int key2;

    ...

    public MyMenuShortcut(int key1, int key2, boolean useShiftModifier) {
        super(key1, useShiftModifier);
        this.key1 = key1;
        this.key2= key2;
    }

    // toString() must be overriden to display in the menu

    public String toString() {
    int modifiers = 0;
    if (!GraphicsEnvironment.isHeadless()) {
        modifiers = Toolkit.getDefaultToolkit().getMenuShortcutKeyMask();
    }
    if (usesShiftModifier()) {
        modifiers |= Event.SHIFT_MASK;
    }
    return KeyEvent.getKeyModifiersText(modifiers) + "+" +
            KeyEvent.getKeyText(key1) + "+" + KeyEvent.getKeyText(key2);
}

I'll leave it up to you to think about how you can accommodate for a large number of keys.

And then in your original code, you would do something like:

MenuShortcut menushortcut_3 = new MyMenuShortcut(KeyEvent.VK_C, KeyEvent.VK_B, true);