TabFocusable

Interface for elements that can participate in Tab key focus navigation.

TabFocusable defines the contract for visual elements that can receive focus through Tab key navigation managed by the TabFocus component. Implementing this interface allows elements to be included in the focus traversal order and provides hooks for focus-related behavior.

Classes implementing this interface typically include form fields, buttons, and other interactive UI elements that should be accessible via keyboard navigation.

Usage example:

class MyCustomField extends View implements TabFocusable {
    public function allowsTabFocus():Bool {
        return enabled && visible; // Only focusable when enabled and visible
    }
    public function tabFocus():Void {
        // Set focus and visual feedback
        screen.focusedVisual = this;
        focused = true;
    }
    public function escapeTabFocus():Void {
        // Handle escape key - lose focus or close dropdown
        screen.focusedVisual = null;
    }
}

Instance Members #

Determines whether this element can currently receive Tab focus.

This method is called by TabFocus during navigation to determine if the element should be included in the focus traversal. Elements can return false when they are disabled, hidden, or otherwise not ready to receive focus.

Called when this element receives focus through Tab navigation.

Implementations should set the appropriate focus state, update visual appearance, and perform any other actions needed when the element becomes focused. This typically includes setting screen.focusedVisual.

Called when the Escape key is pressed while this element has focus.

Implementations can use this to provide escape behavior such as closing dropdowns, canceling edits, or removing focus. The behavior is element-specific and should match user expectations for the particular UI component.