UIHANDLER OnEnter

Invoked when the cursor enters the widget's interactive area.
 ScriptRegion OnEnter(self, motion)
==Arguments==
:;self: - The widget the cursor is hovering over.
:;motion: - True if the handler is being run due to actual mouse movement; false if the cursor entered the frame due to other circumstances (such as the frame being created underneath the cursor)
==Example==
local f = CreateFrame("Frame", nil, nil, "BackdropTemplate")
f:SetPoint("CENTER")
f:SetSize(100, 100)
f:SetBackdrop(BACKDROP_TUTORIAL_16_16)
f:SetScript("OnEnter", function(self, motion)
	GameTooltip:SetOwner(self, "ANCHOR_TOPRIGHT")
	GameTooltip:SetText("Hello World")
end)
f:SetScript("OnLeave", function(self, motion)
	GameTooltip:Hide()
end)
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