Q:

Edit CheckBox and EditText located in another XML file

So I'm in activity Home which has:
setContentView(R.layout.home);

Now, from Home activity, one can go to Settings activity which has:
setContentView(R.layout.settings);

It has a couple of CheckBoxes and EditTexts.
Is it possible to edit the state of those checkboxes from the Home activity?
I already declared them in Home like this:
CheckBox checkBox1 = (CheckBox) findViewById(R.id.checkBox1);

Which finds the ID just fine but the application crashes on the line where I try to 
checkBox1.setChecked(true);

Is it not possible to access it from another activity??
Thank you

A:

In general, an activity cannot directly modify view elements of another activity, since Android makes no guarantees regarding the lifecycle of each activity. Activity A may invoke Activity B, but if memory is running low while B is displayed, A may be destroyed.
You will need to use intents to pass data from one activity to another.

