Android Checkbox preference

问题:

I cannot find any tutorials on checkbox preference. I can use a listpreference, but I can't use checkbox preference. For now, I want that if user sets on the checbox, a toast msg says "true" and if he sets it off, the toast msg says "false". So far I have this:

preferences.xml:

EditPreferences.java:

public class EditPreferences extends PreferenceActivity {      String listPreference;     boolean checkboxPreference;      @Override     public void onCreate(Bundle savedInstanceState) {         super.onCreate(savedInstanceState);         addPreferencesFromResource(R.xml.preferences);     }      public void onStart(Intent intent, int startId) {         getPrefs();     }      private void getPrefs() {         SharedPreferences prefs = PreferenceManager                 .getDefaultSharedPreferences(getBaseContext());         listPreference = prefs.getString("listPref", "nr1");         checkboxPreference = prefs.getBoolean("checkboxPref", true);     } } 

Edit: Solution thanks to David Caunt:

checkboxPreference.     setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {      public boolean onPreferenceChange(Preference preference, Object newValue) {         if (newValue.toString().equals("true")) {             Toast.makeText(getApplicationContext(), "CB: " + "true",                                                     Toast.LENGTH_SHORT).show();         } else {             Toast.makeText(getApplicationContext(), "CB: " + "false",                                                     Toast.LENGTH_SHORT).show();         }         return true;     } }); 

回答1:

You need to add a listener to the Preference in your onCreate method

    final CheckBoxPreference checkboxPref = (CheckBoxPreference) getPreferenceManager().findPreference("checkboxPref");      checkboxPref.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {                     public boolean onPreferenceChange(Preference preference, Object newValue) {             Log.d("MyApp", "Pref " + preference.getKey() + " changed to " + newValue.toString());                    return true;         }     });  

回答2:

You can cast the value of the checkbox into a boolean. This might be safer and more extensible than checking the toString() value.

final CheckBoxPreference checkboxPref = (CheckBoxPreference) getPreferenceManager().findPreference("checkboxPref");  checkboxPref.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {                 public boolean onPreferenceChange(Preference preference, Object newValue) {         if(newValue instanceof Boolean){             Boolean boolVal = (Boolean)newValue;         }         return true;     } });  

文章来源: Android Checkbox preference