timer halts my app

[zubairalimansoor]

i have used timer to change the background color of text box after fixed time.in the main thread i change the back color of text box and satrt timer.in the timer function back color of text box is converted back to its origional color.my application is halted by using this timer.if i do not use timer then it runs fine.i have used System.Threading.Timer.:confused: