### Callbacks common to all gestures:

### `onBegin(callback)`

Set the `onBegin` callback.

### `onStart(callback)`

Set the `onStart` callback.

### `onEnd(callback)`

Set the `onEnd` callback.

### `onTouchesDown(event, stateManager)`

Set the `onTouchesDown` callback which is called every time a finger is placed on the screen.

### `onTouchesMove(event, stateManager)`

Set the `onTouchesMove` callback which is called every time a finger is moved on the screen.

### `onTouchesUp(event, stateManager)`

Set the `onTouchesUp` callback which is called every time a finger is lifted from the screen.

### `onTouchesCancelled(event, stateManager)`

Set the `onTouchesCancelled` callback which is called every time a finger stops being tracked, for example when the gesture finishes.

### `onTouchesChange(event, stateManager)`

Set the `onTouchesChange` callback which is called for every touch event.