Android Question Dangerous action killed my app' [SOLVED]

Hello,

I selected the word "Activity" in the IDE and then ^F
In the seach tab I clicked "Current module" to find results of the current module (I thought)
The all words "Activity" was replaces with an empty string (I felt like an idiot ..).
Corrected all errors found in the IDE by adding the word activity everywhere missing.
When no more errors I launch the app annd ... nothing. Blank (black) screen.

I can see in the log :
*** Service (starter) Create ***
** Service (starter) Start **
** Activity (main) Create, isFirst = true **
** Activity (main) Resume **

that's it ... some body knows how to revert to my previous working project?

Thanks in advance ....