Warning:(40, 5) Do not place Android context classes in Static Fields; this is a memory Leak (and also breaks Instant Run)

Question

I’m coming across this warning from Android Studio. Warning:(40, 5) Do not place Android context classes in Static Fields; this is a memory Leak (and also breaks Instant Run) I have a button that opens a Datepicker Fragment to select the date.

// Botão para chamar o DatePicker Fragment na Activity principal
    btnSelecionaData.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            DialogFragment newFragment = new DatePickerFragment();
            newFragment.show(getSupportFragmentManager(), "datePicker");
        }
    });

When selecting the date I pass this information to an Edittext that is in the class that called this Datepicker Fragment with a . setText() but for this to work Edittext needs to be Static and why Android Studio keeps giving this warning.

// Classe DatePickerFragment
public static class DatePickerFragment extends DialogFragment
        implements DatePickerDialog.OnDateSetListener {

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        // Use the current date as the default date in the picker
        final Calendar c = Calendar.getInstance();
        int year = c.get(Calendar.YEAR);
        int month = c.get(Calendar.MONTH);
        int day = c.get(Calendar.DAY_OF_MONTH);

        // Create a new instance of DatePickerDialog and return it
        return new DatePickerDialog(getActivity(), this, year, month, day);
    }

    public void onDateSet(DatePicker view, int year, int month, int day) {
        // Do something with the date chosen by the user

        //######### ESTE É O EDITTEXT STATIC DA ACTIVITY PRINCIPAL, O QUAL EU PRECISO SETAR COM A DATA ASSIM QUE O USUÁRIO CLICAR NO OK DO FRAGMENT
        etAniver.setText(day+"/"+(month+1)+"/"+year);
        //#########
    }
}

I still don’t understand 100% how language works, so I ask... You have a problem leaving it the way it is?

It seems to me that there is no problem, the value of the variable is needed only while the user is in Activity because once he clicks save the data will be saved in the database and the value of the variable will no longer matter. As I understand this String will be in memory, then it will be replaced by the new value when the user registers another customer. So the memory occupied by 1 static variable would be insignificant... would that be it? Or the data that goes through this variable overlap in memory?

Answer 1

You have a problem leaving it the way it is?

Yes you have.

This will/may cause the memory used by the application to grow progressively.

This happens because part of the memory allocated in this process will not be released when it is no longer needed(memory Leak/memory leak).

The problem is that Edittext, as well as any other type of View, has a reference to a Context, probably in this case an Activity.

An Activity, in the course of using the application, can be destroyed and recreated by the system.
In order that no more than one Activity exists in memory, the memory allocated by the destroyed Activity must be able to be released.

Edittext, when declared static, will exist throughout the entire existence of the application. By keeping the reference to Activity, used to create it, it will not allow the memory allocated to it to be released, if another one has been created.

That is, the problem is not the amount of memory that occupies Edittext but the instances that are referenced by it that cannot be released when they are no longer accurate.

Answer 2

I was able to solve the problem (memory Leak/memory leak) just by editing the Ondateset method inside the Datepickerfragment class. It was like this:

public void onDateSet(DatePicker view, int year, int month, int day) {
    // Do something with the date chosen by the user
    TextView tv1= (TextView) getActivity().findViewById(R.id.et_aniver);
    tv1.setText(view.getDayOfMonth()+"/"+(view.getMonth()+1)+"/"+view.getYear());

}

This way the Edittext variable in the main Activity nay needs to be Static, thus solving the problem of (memory Leak/memory leakage). The statement was so now:

private EditText etAniver;