Display apparatus for selecting and executing menu items on a user interface, and controlling method thereof

A display apparatus, comprising:

• a display;
• and
• a processor configured to:
• control the display to display:
• a plurality of menu items comprising a power menu item, a source menu item, and a volume menu item, and
• an indicator for selecting a menu item of the plurality of menu items,
• wherein the plurality of menu items respectively correspond to a plurality of functions for controlling the display apparatus;
• receive a user operation of pressing a single key while the plurality of menu items are displayed on the display;
• identify the received user operation as either a short click or a long press based on an input time of the user operation of pressing the single key;
• in response to the user operation of pressing the single key being identified as the short click while the indicator is positioned on a menu item of the plurality of menu items, move the indicator from the menu item to another menu item of the plurality of menu items;
• in response to the user operation of pressing the single key being identified as the long press while the indicator is positioned on a menu item of the plurality of menu items, perform a function corresponding to the menu item on which the indicator is positioned;
• and
• maintain a speed of performing the function within a preset time for which an input of the long press is continued and accelerate the speed of performing the function after the preset time passes.