GUI: Area

Area is a hidden button with no text. It is especially helpful on images.

Area is a class with three functions: 

• define, 
  
• enable 
  
• and check.
  

It needs to be declared.

area myArea;

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, 
• index, optional, default = 0x0000

The size of the area is defined as a vector 

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

void setup() {        
myArea.dDefine(&myLCD, 160, 120, 79, 59);

enable makes the area active.

myArea.enable(true);     

myLCD.setFont(1);     
myLCD.gText(0, 0, 0xffff, " 1 2 3 4");     
myLCD.gText(0, 20, 0xffff, "1234567890123456789012345678901234567890");     
myLCD.gText(0, 60, 0xffff, ftoa(myLCD.fontX(), 0, 8));     
myLCD.setFont(0);     
myLCD.gText(0, 80, 0xffff, " 1 2 3 4 5");     
myLCD.gText(0, 100, 0xffff, "12345678901234567890123456789012345678901234567890123");     
myLCD.gText(0, 120, 0xffff, ftoa(myLCD.fontX(), 0, 8)); } 

In the main loop, the area is checked. 

void loop() {   
    // quit   
    if (myArea()) {     
        myLCD.off();     
        while(true);   
    }           
    myLCD.setFont(0);   
    myLCD.setFontSolid(true);   
    myLCD.gText( 250, 225, 0xffff, String(millis()-l));   
    l=millis(); 
}