Tell if Activity was started from launcher or navigated back to back button

I'm trying to discern, during onStart(), whether my Activity was started from the home screen or "back" from another activity.

getIntent().hasCategory("android.intent.category.LAUNCHER")

does not work, as the activity's intent stays the same.

I want to display a dialog box when the main activity starts, but I don't want it popping up every time a user goes back to the main activity after visiting another.

Is开发者_JAVA百科 there any way to accomplish this?

Thanks for any help! -Chase

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Yes it is possible to launch a dialog box only when the main activity starts the first time, but I save state on a soft kill. So if you save state in onSaveInstanceState on a soft kill you can look for a null bundle in onCreate. If the bundle is null, then this is the first launch. If the bundle is not null, then you are returning from a soft kill. If you save state in onRetainNonConfigurationState then the code looks like:

    // RESTORE STATE HERE
    // Save state in onStop (prefs) and onRetainNonConfigurationInstance (ConfuseTextState)
    state= (ConfuseTextState)getLastNonConfigurationInstance();
    if (state != null) {  // at least second pass, get non view state from onRetainNonConfigurationInstance
        try {               
            this.isShowCharCount= state.isShowCharCount;
                this.timeExpire= state.timeExpire;
                this.timeoutType= state.timeoutType;
                this.isValidKey= state.isValidKey;
                this.password= state.password;
                this.isAutoLaunch= state.isAutoLaunch;
                //Log.d(TAG,"restoredStateFromLastConfiguration");
        }
        catch(Exception e){
            Log.d(Utilities.TAG,"FailedToRestoreState",e);
        }
    }
    else { // first pass, get saved state from preferences on first pass if they exist
        // Restore preferences (8) on hard kill when USER hit back and killed us
        SharedPreferences prefs = getPreferences(MODE_PRIVATE); // singleton
        if (prefs  != null){...
        }   // else state is from xml files and default instance values
        // SUPPORT EASY LAUNCH
        if (isAutoLaunch){ // launch on first show only
            this.showDialog(DIALOG_EASY_LAUNCH); //<== SHOW YOUR ALERT HERE!
        }
    }