// Draw draws this primitive onto the screen. Implementers can call the

// screen's ShowCursor() function but should only do so when they have focus.

// (They will need to keep track of this themselves.)

Draw(screen tcell.Screen)

// GetRect returns the current position of the primitive, x, y, width, and

// height.

GetRect() (int, int, int, int)

// SetRect sets a new position of the primitive.

SetRect(x, y, width, height int)

// InputHandler returns a handler which receives key events when it has focus.

// It is called by the Application class.

//

// A value of nil may also be returned, in which case this primitive cannot

// receive focus and will not process any key events.

//

// The handler will receive the key event and a function that allows it to

// set the focus to a different primitive, so that future key events are sent

// to that primitive.

//

// The Application's Draw() function will be called automatically after the

// handler returns.

//

// The Box class provides functionality to intercept keyboard input. If you

// subclass from Box, it is recommended that you wrap your handler using

// Box.WrapInputHandler() so you inherit that functionality.

InputHandler() func(event *tcell.EventKey, setFocus func(p Primitive))

// Focus is called by the application when the primitive receives focus.

// Implementers may call delegate() to pass the focus on to another primitive.

Focus(delegate func(p Primitive))

// HasFocus determines if the primitive has focus. This function must return

// true also if one of this primitive's child elements has focus.

HasFocus() bool

// Blur is called by the application when the primitive loses focus.

Blur()

// MouseHandler returns a handler which receives mouse events.

// It is called by the Application class.

//

// A value of nil may also be returned to stop the downward propagation of

// mouse events.

//

// The Box class provides functionality to intercept mouse events. If you

// subclass from Box, it is recommended that you wrap your handler using

// Box.WrapMouseHandler() so you inherit that functionality.

MouseHandler() func(action MouseAction, event *tcell.EventMouse, setFocus func(p Primitive)) (consumed bool, capture Primitive)