button symbol to make mcs visible one by one

Hi.

There are 2 errors:

- The if  keyword must be in lowercase (if);

- And you're using assignment operators (=) instead of equality operators (==).

Also, use else if to make your code more efficient.

It should be like this:

this.sb1.visible = false;
this.sb2.visible = false;
this.sb3.visible = false;
this.sb4.visible = false;

btn_integer = 0; // you're declaring a global variable here. Is this what you really want? If not, use the var keyword. E.g.: var btn_integer = 0;

this.btn.addEventListener("click", clickHandler.bind(this));

function clickHandler(event) 
{
	btn_integer = btn_integer + 1;
		
	if (btn_integer == 1) 
	{
		this.sb1.visible = true;
	} 
	else if (btn_integer == 2)  
	{
		this.sb2.visible = true;
	}
	else if (btn_integer == 3)  
	{
		this.sb3.visible = true;
	}
	else if (btn_integer == 4)  
	{
		this.sb4.visible = true;
	}
}

Regards,

JC