Priority Order

The appending order MUST follow the priority as follow

Priority 1	Priority 2	Priority 3
-clk: clicked event. -focus: focused event. -over: mouse over event. -drag: dragged event. -drop: dropped event.	-seld: selected event. -ck: checked event. -unck: unchecked event.	-disd: disabled event. -visi: visited event. -hide: hidden event. -invalid invalid event. -readonly readonly event.