Question

I’ve been trying many different ways and getting null pointer exceptions.

Scenario: Activity1 loads on start and calls Activity2 if the num of rows in the table is 0. Now I want it to go back to Activity1 when the number of rows is 0 and that call would coem from the db handler.
In the database handler class:

    if(num ==0){
        Activity1 bs1 = new Activity1();
        Context context = bs1.getApplicationContext();
        Intent intent = new Intent();//
        intent.setClass(context, Activity1.class);
        intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        context.startActivity(intent);

    }

Activity1 onCreate()

    int num = db.numOfRows();
    if(num==0){
        setContentView(R.layout.main);
    } else {    
        startActivity(new Intent(this, Activity2.class));//
    }

Activity2 onCreate()

        super.onCreate(savedInstanceState);
        setContentView(R.layout.moreprojects);
        populateRows();

Thanks in advance.

Answer 1

You dont use constructor to call new activity. See below:

Context context = bs1.getApplicationContext();
Intent intent = new Intent();
intent.setClass(context, MainActivity.class);
i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); //required to launch from non-activity
context.startActivity(intent);