How to keep focus within modal dialog?

Question

I\'m developing an app with Angular and Semantic-UI. The app should be accessible, this means it should be compliant with WCAG 2.0. To reach this p

Answer 1

Here's my solution. It traps Tab or Shift+Tab as necessary on first/last element of modal dialog (in my case found with role="dialog"). Eligible elements being checked are all visible input controls whose HTML may be input,select,textarea,button.

$(document).on('keydown', function(e) {
    var target = e.target;
    var shiftPressed = e.shiftKey;
    // If TAB key pressed
    if (e.keyCode == 9) {
        // If inside a Modal dialog (determined by attribute role="dialog")
        if ($(target).parents('[role=dialog]').length) {                            
            // Find first or last input element in the dialog parent (depending on whether Shift was pressed). 
            // Input elements must be visible, and can be Input/Select/Button/Textarea.
            var borderElem = shiftPressed ?
                                $(target).closest('[role=dialog]').find('input:visible,select:visible,button:visible,textarea:visible').first() 
                             :
                                $(target).closest('[role=dialog]').find('input:visible,select:visible,button:visible,textarea:visible').last();
            if ($(borderElem).length) {
                if ($(target).is($(borderElem))) {
                    return false;
                } else {
                    return true;
                }
            }
        }
    }
    return true;
});