Class DropDownDeactivateGuard

java.lang.Object
com.iizigo.swt.DropDownDeactivateGuard
public final class DropDownDeactivateGuard extends Object
Decides whether a deactivation closes a drop-down shell that closes when it or its parent shell loses the activation, such as the drop-down of the ColorSelectionWidget.

On GTK the activation of a shell is asynchronous: the deactivation that the opening of a drop-down causes arrives through the event loop after open() returned (measured on STJERNA: the parent shell deactivated 77-148 ms after the drop-down was shown, and the drop-down closed by itself), where on Windows and macOS it arrives inside open(). On GTK, a deactivation that arrives within GTK_GRACE_MS of the opening, while the pointer or the focus is still on the widget or the drop-down, is that echo of the opening and is ignored. Any later deactivation, and every deactivation on every other platform, closes the drop-down as before.

CC-FIX-COLOR-DROPDOWN-GTK (FH-D-5, IIZI-GO-COLOR-DROPDOWN-CLOSES-ON-GTK).

  • Field Details

    • GTK_GRACE_MS

      public static final long GTK_GRACE_MS
      The time after the opening of a drop-down within which a deactivation on GTK may be the echo of the opening, in milliseconds.
      See Also:

  • Constructor Details

    • DropDownDeactivateGuard

      public DropDownDeactivateGuard(BooleanSupplier isPointerOrFocusOnWidget)
      Constructs the guard of the running platform (SWT.getPlatform()) with the system clock.
      Parameters:
      isPointerOrFocusOnWidget - Tells whether the pointer or the focus is on the widget or its drop-down; asked only on GTK, within the grace time.

    • DropDownDeactivateGuard

      public DropDownDeactivateGuard(String platform, LongSupplier clock, BooleanSupplier isPointerOrFocusOnWidget)
      Constructs the guard of a platform with a clock.
      Parameters:
      platform - The SWT platform, as SWT.getPlatform() names it ("gtk", "win32", "cocoa").
      clock - The clock, in milliseconds.
      isPointerOrFocusOnWidget - Tells whether the pointer or the focus is on the widget or its drop-down; asked only on GTK, within the grace time.

  • Method Details

    • opened

      public void opened()
      Notes the opening of the drop-down: called just before its shell is opened.

    • isIgnored

      public boolean isIgnored()
      Tells whether a deactivation that arrives now is ignored: true only on GTK, within GTK_GRACE_MS of the last opening, while the pointer or the focus is on the widget or the drop-down.
      Returns:
      true to keep the drop-down open, false to close it as before.