我的 res 文件夹中有一个 settings.xml 来管理用户设置。我将其加载到一个 fragment 中。为此,我需要将这些设置存储到后端服务中。我想知道用户使用了哪些值,或者每当用户更改了我想知道的设置,以便我更新服务器的设置。
我已经尝试了很多方法,如下面的代码所示,但我无法读取值。我尝试使用 Toast 和日志语句来检查监听器,但没有出现任何表明未调用监听器的内容。我做错了什么吗?
用户设置 fragment .java
public class UserSettingFragment extends PreferenceFragment implements OnSharedPreferenceChangeListener {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.settings);
//Method 1
PreferenceScreen shared = getPreferenceScreen();
shared.setOnPreferenceChangeListener(new OnPreferenceChangeListener() {
@Override
public boolean onPreferenceChange(Preference preference, Object newValue) {
// TODO Auto-generated method stub
Toast.makeText(getActivity().getApplicationContext(), "Changed", Toast.LENGTH_LONG).show();
Log.d("preference", "change");
return true;
}
});
final SharedPreferences sharedPref = getActivity().getPreferences(Context.MODE_PRIVATE);
Preference gender = (Preference) findPreference("gender");
//Method 2
// Get the custom preference
Preference mypref = (Preference) findPreference("mypref");
mypref.setOnPreferenceChangeListener(new OnPreferenceChangeListener() {
@Override
public boolean onPreferenceChange(Preference preference, Object newValue) {
// TODO Auto-generated method stub
String highScore = sharedPref.getString("gender", "Male");
Toast.makeText(getActivity().getApplicationContext(), "Changed to " + highScore, Toast.LENGTH_LONG).show();
Log.d("preference", "change");
return false;
}
});
} //Method 3
@Override
public void onSharedPreferenceChanged(SharedPreferences sharedPreferences,
String key) {
// TODO Auto-generated method stub
Toast.makeText(getActivity().getApplicationContext(), "Changed", Toast.LENGTH_LONG).show();
}
设置.xml
<?xml version="1.0" encoding="utf-8"?>
<SwitchPreference
android:key="gender"
android:title="I am"
android:switchTextOn="Female"
android:switchTextOff="Male"
/>
</PreferenceCategory>
最佳答案
由于您使用的是 PreferenceFragment
,因此您需要在 onResume
和 onPause
方法中注册和取消注册 OnSharedPreferenceChangeListener
对于您在问题中提到的方法#3。
public class UserSettingFragment extends PreferenceFragment implements SharedPreferences.OnSharedPreferenceChangeListener {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.settings);
}
@Override
public void onResume() {
super.onResume();
getPreferenceScreen().getSharedPreferences().registerOnSharedPreferenceChangeListener(this);
}
@Override
public void onPause() {
super.onPause();
getPreferenceScreen().getSharedPreferences().unregisterOnSharedPreferenceChangeListener(this);
}
@Override
public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
Toast.makeText(getActivity().getApplicationContext(), "Changed key: " + key, Toast.LENGTH_LONG).show();
}
}
关于Android:无法从 settings.xml 获取首选项值,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/22882144/