I´d like to show a simple information dialog with an Ok-Button, about whats new in this version, but it should show only at the first start. Whats the best way to implement
I would (and have) used a SharedPreferences with a boolean or int value. Simply check if the last version is older than the current version and update the int. Here's a nice little snipit.
//check to see if we need to show whats new or not
SharedPreferences config = getSharedPreferences(MY_PREFS_STRING, 0);
int lastVersion = config.getInt(KEY_VERSION, -1);
if(currentVersion > lastVersion ){
showDialog(id);
//set this as lastVersion
}
with a boolean variable stored somewhere : preferences, DB, SD card, ..
A number of solutions are documented here:
What is SharedPreferences in Android?