Using shared preferences editor
I'm slowly working through an Android learning book and was given the following code to assign user data:
package com.androidbook.triviaquiz;
import android.app.Activity;
import android.content.SharedPreferences;
public class QuizActivity extends Activity {
public static final String GAME_PREFERENCES = "GamePrefs";
SharedPreferences settings = getSharedPreferences(GAME_PREFERENCES, MODE_PRIVATE);
SharedPreferences.Editor prefEditor = settings.edit();
prefeditor.putString("UserName", "John Doe"); //**syntax error on tokens**
prefEditor.putInt("UserAge", 22); //**syntax error on tokens**
prefEditor.commit();
}
Ho开发者_如何学JAVAwever, I get an error (lines indicated with comments) that underlines the period and says "misplaced construct" and also that underlines the arguments saying "delete these tokens". I have seen this done in other applications in the same format, I don't understand what is wrong.
Edit: Of course! Those statements cannot be put directly into the class at that level and must be inside a method, something like this:
public class QuizActivity extends Activity {
public static final String GAME_PREFERENCES = "GamePrefs";
@Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
SharedPreferences settings = getSharedPreferences(GAME_PREFERENCES, MODE_PRIVATE);
SharedPreferences.Editor prefEditor = settings.edit();
prefEditor.putString("UserName", "John Doe");
prefEditor.putInt("UserAge", 22);
prefEditor.putString("Gender", "Male");
prefEditor.commit();
}
}
I think you may missed up OnCreate() method ,let be sure you should place the shared preference in your OnCreate() method... i just edited your code go through it
please go through the code...below
public class A extends Activity {
static SharedPreferences settings;
public static final String PREFS_NAME = "YourPrefName";
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
settings = getSharedPreferences(PREFS_NAME, 0);
Log.v("UserName"," - "+settings.getString("username","android"));
SharedPreferences.Editor editor = settings.edit();
editor.putString("username","Change Android");
editor.commit();
Log.v("UserName after changed editing preference key value"," - "+settings.getString("username","android"));
}
}
SharedPreferences will work out side a onCreate() method as long as it has a context:
SharedPreferences settings = getAplicationContext().getSharedPreferences(GAME_PREFERENCES, MODE_PRIVATE);
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