Pushbutton Widget

Hi there, im quite new to CCS and this is my first time using TM4C123G.

I've been trying to create a widget of 4 pushbuttons with different functions.

My intended push button functions are as follow:

-CLEAR (to clear the whole screen)
-SPLIT (to split the screen into two different display)
-LEARN (to memorize a waveform for comparison in the later part)
-ALARM RESET (to reset an alarm buzzer)

The function of the CLEAR has not been set yet because i couldn't get the re-painting thing stop /:
And, i would also like to know how do i; 

1. Include more than one child to one widget?
For example, i would like to link my 4 push buttons to the &g_sBackground.

2. Draw displays into the widgets?
Can i just use stuff like GrStringDraw etc? 

I've tried the lab10 worksheet but it seems like it isnt sufficient for what i need /:
Thankyou!

I've tried to start off with the simplest CLEAR push button function but i came up with a problem whereby the screen keeps repainting on its own.

#include <stdint.h>
#include <stdbool.h>
#include "inc/hw_memmap.h"
#include "inc/hw_types.h"
#include "driverlib/interrupt.h"
#include "driverlib/sysctl.h"
#include "driverlib/gpio.h"
#include "grlib/grlib.h"
#include "grlib/widget.h"
#include "grlib/canvas.h"
#include "grlib/pushbutton.h"
#include "Kentec320x240x16_ssd2119_8bit.h"
#include "touch.h"

extern tCanvasWidget g_sBackground;
extern tPushButtonWidget g_sClearBtn;

void ClearButtonPress(tWidget *pWidget);

Canvas(g_sHeading, &g_sBackground, &g_sLearnBtn, 0,
		&g_sKentec320x240x16_SSD2119, 120, 20, 200, 23,
		(CANVAS_STYLE_FILL | CANVAS_STYLE_OUTLINE | CANVAS_STYLE_TEXT | CANVAS_STYLE_TEXT_LEFT),
		ClrBlack, ClrWhite, ClrWhite, g_psFontCm14, "BREATHING RATE:", 0, 0);

Canvas(g_sBackground, WIDGET_ROOT, 0, 0,
		&g_sKentec320x240x16_SSD2119, 0, 23, 320, (240 - 23),
		CANVAS_STYLE_FILL, ClrBlack, 0, 0, 0, 0, 0, 0);

RectangularButton(g_sClearBtn, &g_sBackground, &g_sHeading, 0,
		&g_sKentec320x240x16_SSD2119, 0, 200, 60, 40,
		(PB_STYLE_OUTLINE | PB_STYLE_TEXT_OPAQUE | PB_STYLE_TEXT |
				PB_STYLE_FILL), ClrBlack, ClrWhite, ClrGreen, ClrGreen,
				g_psFontCmss14b, "LEARN", 0, 0, 0, 0, ClearButtonPress);
bool g_RedLedOn = false;

void ClearButtonPress(tWidget *pWidget){

	g_RedLedOn = !g_RedLedOn;

	if(g_RedLedOn){
		GPIOPinWrite(GPIO_PORTF_BASE, GPIO_PIN_1, 0x02);
	}
	else{
		GPIOPinWrite(GPIO_PORTF_BASE, GPIO_PIN_1, 0x00);
	}
}
int main(void){

	SysCtlClockSet(SYSCTL_SYSDIV_4 | SYSCTL_USE_PLL | SYSCTL_OSC_MAIN | SYSCTL_XTAL_16MHZ);

	SysCtlPeripheralEnable(SYSCTL_PERIPH_GPIOF);
	GPIOPinTypeGPIOOutput(GPIO_PORTF_BASE, GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3);
	GPIOPinWrite(GPIO_PORTF_BASE, GPIO_PIN_1|GPIO_PIN_2|GPIO_PIN_3, 0x00);

	Kentec320x240x16_SSD2119Init();

	TouchScreenInit();

	WidgetAdd(WIDGET_ROOT, (tWidget *)&g_sBackground);
	WidgetAdd((tWidget *)&g_sBackground, (tWidget *)&g_sClearBtn);

	TouchScreenCallbackSet(WidgetPointerMessage);

	WidgetPaint(WIDGET_ROOT);

	while(1){
		WidgetMessageQueueProcess();
	}
}