The GamepadButton interface defines an individual button of a gamepad or other controller, allowing access to the current state of different types of buttons available on the control device.

A GamepadButton object is returned by querying any value of the array returned by the buttons property of the Gamepad interface.

GamepadButton.pressed Read only

A boolean value indicating whether the button is currently pressed (true) or unpressed (false).

GamepadButton.touched Read only

A boolean value indicating whether the button is currently touched (true) or not touched (false).

GamepadButton.value Read only

A double value used to represent the current state of analog buttons, such as the triggers on many modern gamepads. The values are normalized to the range 0.0 —1.0, with 0.0 representing a button that is not pressed, and 1.0 representing a button that is fully pressed.

The button values in the following example are stored as an array of GamepadButton objects. This simple example checks to see if the GamepadButton.value of a button is greater than 0, or if the GamepadButton.pressed property indicates the button has been pressed.

function gameLoop() {
  const gp = navigator.getGamepads()[0];

  if (gp.buttons[0].value > 0 || gp.buttons[0].pressed) {
    b--;
  } else if (gp.buttons[1].value > 0 || gp.buttons[1].pressed) {
    a++;
  } else if (gp.buttons[2].value > 0 || gp.buttons[2].pressed) {
    b++;
  } else if (gp.buttons[3].value > 0 || gp.buttons[3].pressed) {
    a--;
  }

  ball.style.left = `${a * 2}px`; // ball is a UI widget
  ball.style.top = `${b * 2}px`;

  requestAnimationFrame(gameLoop);
}

Using the Gamepad API