Question

I’ve a method which is making a huge calculation and then calls an intent as follows

public void sampleMethod(final Context cont)
{
 .
 .
 (huge calculation [50-80 lines])
 .
 .
Intent intent = new Intent(cont, TimesheetMain.class);
            finish();
            startActivity(intent);
}

This is present in Activity ‘SampleActivity’. When I’m trying to access it through on object of Activity ‘SampleActivity’ from Activity ‘B’ as follows:

Context context = this;
SampleActivity sa = new SampleActivity();
sa.sampleMethod(context);

I’m getting a NullPointerException at the startActivity line of code while accessing it from Activity ‘B’. I can’t figure out where am i going wrong in here. Please help me out

EDIT 2

This seem to work when i added context to it like cont.startActivity(intent), but i need to know why shouldn’t i use another class or another activity’s function in a secondary class? Is the android framework is the reason? I’ve been doing this (without the intent part) for the past two months or so, i never faced any sudden force close issues in either emulator or in device(Nextbook professional 7 SE); Please explain it with a legit example

Answer 1

try the follwng updated code:

public void sampleMethod(final Activity cont)
{
Intent intent = new Intent(cont, TimesheetMain.class);
            cont.finish();
            cont.startActivity(intent);
}

also move this method to a util class and call it from activity and pass the activity reference as follows

class ActivityB extends Activity
{
.
.
.

Util.sampleMethod(this);
}