CheckBoxPreference isChecked causes a FC in a preferenceActivity

Question

When I check if the checkbox is checked, I get a Force Close in the following code:

public class preference extends PreferenceActivity implements OnSharedPreferenceChangeListener {

    public static final String nwd = "nwd";
    private CheckBoxPreference nwd_pref;


    @Override
    public void onCreate(Bundle savedInstanceState) {
        ...
        nwd_pref = (CheckBoxPreference)getPreferenceScreen().findPreference(nwd);
        ...
    }

    @Override
    public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
    ...
    if (nwd_pref.isChecked()){
       // do code
    }
    ...
    }
}

I found this example during searching but looks the same to me.

Thanks for your help!

You should add a logcat, or at least what's the exception, are you sure that `nwd_pref` is not null? — MByD, May 27 '11 at 16:18
This was the problem due to an type. Thanks. Shall add logcat in the future. — patrick, May 27 '11 at 17:24

score 1 · Accepted Answer · answered May 27 '11 at 16:30

1

findPrefernece(..) will "Return The Preference with the key, or null." It looks like "nwd" hasn't been set yet.

answered May 27 '11 at 16:30

Haphazard

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It is indeed "null", this while it does work for my EditTextPreference. – patrick May 27 '11 at 17:14
So you can do a null check and then default it to checked or unchecked if it has not been set already. – Haphazard May 27 '11 at 17:20
Found it, there was a typo in my xml. Thx – patrick May 27 '11 at 17:23

CheckBoxPreference isChecked causes a FC in a preferenceActivity

1 Answers1