Editing WoW:UIHANDLER OnClick

{{widgethandler}}
The '''OnClick''' handler is called when a UI widget that supports clicking (i.e. is derived from a Button) is clicked. Region derivatives like Frame only implement OnMouseDown / OnMouseUp handlers.

== Arguments ==
;self : widget being clicked
;button : [mouse] button used to click the widget. Due to widget:Click(button, down), button argument may be anything, although the following five values are common for normal mouse clicks: "LeftButton", "RightButton", "MiddleButton", "Button4", "Button5".
;down : Boolean - 1 (true) if the trigger button is currently being held down, nil (false) otherwise.

==Example==
 local taunts = {"I'm a button.", "Quit clicking me.", "That's enough.", "Stop it!", "I'm leaving!"};
 local widget = CreateFrame("Button", "TauntingButton", UIParent, "UIPanelButtonTemplate");
 widget:SetWidth(200); widget:SetHeight(24); widget:SetPoint("CENTER");
 widget:RegisterForClicks("AnyUp");
 widget:SetScript("OnClick", function (self, button, down)
  self:SetID((self:GetID() or 1) + 1);
  if taunts[self:GetID()] then
   self:SetText(taunts[self:GetID()]);
  else
   self:Hide();
  end
 end);

The named arguments are also available in XML handlers:
 <Button name="foo" ...>
   ...
   <Scripts>
     ...
    <OnClick>self:SetText("You clicked with " .. button);</OnClick>
   </Scripts>
  </Button>