hV_GUI — Button

Button is a class with four functions: define, enable, draw and check.

It needs to be declared: 

Other specialised buttons include radio-buttons, check-box and flip-flop.

They are optimised with blac-and-white interface and support haptic feed-back.

The syntax of define allows multiple options:

Parameters of define are

• LCD to which the button belongs, with &myLCD
  
• top left x1 or point x0, 
• top left y1 or point y0, 
• bottom right x2 or x-width dx, 
• bottom right y2 or y-height dy, 
• label, 
• text colour 16-bit coded, 
• high colour 16-bit coded, 
• low colour 16-bit coded, optional or half the high colour otherwise 
• font size 9=automatic, 0..3=as per standard LCD sizes, optional or 9 otherwise

Note the short and the long syntaxes. The size of the button is defined as a vector with 

• a point (x0, y0) 
• and a size (dx, dy) for functions starting with a d.

The funciton enable() makes the button active, and draw() draws it on the screen.

In the main loop, the button is checked.