升级控件模块，封装focus相关的几个静态方法

Zframework/init.lua

@@ -190,7 +190,7 @@ function love.touchreleased(id,x,y)
 		WIDGET.release(x,y)
 		touching=false
 		if WIDGET.sel and not WIDGET.sel.keepFocus then
-			WIDGET.sel=false
+			WIDGET.unFocus()
 		end
 	end
 	if SCN.touchUp then SCN.touchUp(x,y)end
@@ -214,7 +214,7 @@ local function noDevkeyPressed(key)
 			end
 		end
 	elseif key=="f4"then	if not kb.isDown("lalt","ralt")then LOG.copy()end
-	elseif key=="f5"then	if WIDGET.sel then print(WIDGET.sel)end
+	elseif key=="f5"then	print(WIDGET.isFocus()or"no widget selected")
 	elseif key=="f6"then	for k,v in next,_G do print(k,v)end
 	elseif key=="f7"then	if love._openConsole then love._openConsole()end
 	elseif key=="f8"then	devMode=nil	LOG.print("DEBUG OFF")
@@ -224,8 +224,8 @@ local function noDevkeyPressed(key)
 	elseif key=="f12"then	devMode=4	LOG.print("DEBUG 4")
 	elseif key=="\\"then	_G["\100\114\97\119\70\87\77"]=NULL
 	elseif devMode==2 then
-		if WIDGET.sel then
-			local W=WIDGET.sel
+		local W=WIDGET.sel
+		if W then
 			if key=="left"then W.x=W.x-10
 			elseif key=="right"then W.x=W.x+10
 			elseif key=="up"then W.y=W.y-10