sharedpreferences

问题 i am self_learner to android. I have two screens.The first screen contains one edittext and a button,the edittext is to get the input from the user and button is to call the tabhost's activity which is on the second screen. During run time, after getting input from the user,it should show the appropriate values (as per the user's input) to any one of the tab of a tabhost which is on the second screen. But here my problem is,its showing the answer on the separate screen,not on the tabhost

问题 I'm new to Android. I'm doing an app for an university exam. I have to do an application for a travel agency. I'd like to manage the user session with shared preferences in order to save basic information and the eventually travels that the user booked. I can't find an example on the web that combine the registration and login forms. I wrote this code but it's not working. It doesn't show any error. I think what I wrote it's not logic. I'd like to register first and login with the information

问题 I have a hash map table as below, HashMap<String, String> backUpCurency_values = new HashMap<String, String>(); and i want to store these value for future use.. how can i do that? Edit: i will store to Country names and currencyvalue as key and value pair... 回答1: You should just use a for-each loop and iterate through the map like this: SharedPreferences.Editor editor = getSharedPreferences(PREFS_NAME, 0).edit(); for( Entry<String, String> entry : backUpCurency_values.entrySet() ) editor

问题 I've been doing my homework on how to backup SharedPreferences in my Android application, especially using reflection to maintain backwards compatibility. At least I've been trying. Unfortunately, none of my code actually ends up creating a backup! This includes forcing adb bmgr commands on the emulator as explained here. So I'm wondering if the community could perhaps help me out and in the process come up with some better documentation? Here's my code. To keep this as generic as possible

问题 I'm building an app which searches the web using search engine. I have one edittext in my app from which user will search the web. I want to save the search keywords just like browser history does. I'm able to save and display it with the last keyword but I can't increase the number of searches result. I want to display the last 5 searhes. Here is my code : public class MainActivity extends Activity implements OnClickListener { Button insert; EditText edt; TextView txt1, txt2, txt3, txt4,

问题 I have parsed JSON successfully but now i want to Cache it for offline usage, even internet is not available, and if any new entry comes i want to cache that as well. And what would be the best option to cache data ? SharedPreferences or SQLite database Here is my code, which i am using to Parse JSON: public class MainActivity extends Activity { ArrayList<Actors> actorsList; ActorAdapter adapter; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState)

问题 EDIT: The problem described below was due to a very peculiar device issue not caused by any coding-related problem. I have a preferenceActivity in which I have many checkBoxPreferences. The checkBoxPreference is suppose to save the the default shared preferences file, and then be called again when I open the app in order to update the UI. This does not happen like it's suppose to. If I close the app and open it back up, my values remain like they are suppose to, but if I use task manager to

问题 How do I retrieve shared preferences that have been saved from a previous activity? Do I need to enable file writing or some other manifest modifications? 回答1: You don't need any special manifest modificaiton to achieve that. Assuming you have already saved preferences you can read those preferences at anytime doing something like I show bellow. Write on Shared Preferences file: SharedPreferences prefs = getSharedPreferences("your_file_name", MODE_PRIVATE); SharedPreferences.Editor editor =

问题 My app uses SharedPreferences (with the help of a PreferenceActivity) to store all settings. But sometimes all settings are deleted and all values are set back to default. Mostly on Android 3.x tabs. On normal smartphones there are no problems. I have observed that all settings are deleted when the application process is killed by Android. I noticed this because the notification icon is no longer displayed. I also wonder why the process is killed on tablets and not on smartphones. On my

问题 I was wondering if it could be possible to save in the shared preferences an array of Strings, in a way that, every time we save a certain String, we store it in that array. For example I have a list of locations with a certain ID that I want to mark as favorite. The ideal situation would be, having an array and saving a certain location ID (let's call it Location1) in that array, so next time I want to mark a new location as favorite (let's call it Location2), I retrieve that array (which so