[1.7.2] Give a button a function?

[Pardeep]

I've added a button to the GuiOptions of vanilla minecraft using Java Reflection. However, now I don't know how to get it so that a new GuiOpens when the button is pressed, as I don't know how to access the actionPerformed method of GuiOptions and use it.

 

Is there a way to do this, or is there possibly an eventhandler I could use?

 

Thanks in advance?

 

Here's my code if it helps:

public void onRenderTick(RenderTickEvent event)
{
	try
	{
		GuiScreen activeGUI = Minecraft.getMinecraft().currentScreen;

		if(activeGUI != null && activeGUI instanceof GuiOptions) //whatever GUI you want to add a/multiple button/s to
		{
			Field field1 = GuiScreen.class.getDeclaredField("buttonList");
			field1.setAccessible(true);
			List buttonList = (List) field1.get(activeGUI);			
			buttonList.add(new CustomButton(300, 1, 1, 100, 20, "Update Checker")); //you have to make a class extending GuiButton to add function to your button	
		}
	}
	catch(Exception e)
	{
		e.printStackTrace();
	}
}

NB: the button is visible 100% and works. Just don't know how to add function.