Android: Debugging does not work for android

Descriptiom:

1.Create a breakpoint in your app at an appropriate location in the code & launch the app in debug mode.
2.Observe the results.

Actual Result:

1.The app launches & stays at the appcelerator splash screen.
2.The "debug on android device" dialog stays on the screen with the progress indicator spinning next to 'Device connected.Performing precompilation tasks'.

NOTE : Refer that attached screen shot for reference.

Expected result:
1.The app should launch & halt & the code which has the breakpoint rather than the appc splash.
2. We should be able to step over, step into etc the breakpoint.
2. The "debug on android device" dialog should complete its steps & close.