Q:

Access variable in Activity through Intent.putExtra

i want to know that if i am acessing the varaible through intent.putextra then what happen if the value got change of that variable clearing through example would be appericiated?

A:

Its pretty simple and straight forward. You need to make use of startActivityForResult, setResult and onActivityResult to keep the values updated between activities. For example:
From your current Activity, start a new one as below:
Intent i = new Intent(this, SomeClass.class);
i.putExtra("value", 1001);
startActivityForResult(i, 1);

In your SomeClass Activity, get the value, change it and return it back as below:
int value = getIntent().getIntExtra("value", 0);
value += 100;   //changing the value for demo purposes
Intent j = new Intent();
j.putExtra("modified_value", value);
setResult(Activity.RESULT_OK, j);
finish();

Now back to your parent activity, do the following to receive the modified value:
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    if(requestCode == 1){
        if(resultCode == Activity.RESULT_OK){
            int modified_value = data.getIntExtra("modified_value", 0);
        }
    }
}

