How can I save the the settings of my app? Right now, for example, I have a togglebutton to turn on/off. But if I restart my phone, the toggle button is turned back on. Its not saving the settings if I completely close the app. Can I like the save the settings to the phone as cookies?
Use Shared Preferences. Like so:
Put this at the top of your class: public static final String myPref = "preferenceName";
Create these methods for use, or just use the content inside of the methods whenever you want:
public String getPreferenceValue()
{
SharedPreferences sp = getSharedPreferences(myPref,0);
String str = sp.getString("myStore","TheDefaultValueIfNoValueFoundOfThisKey");
return str;
}
public void writeToPreference(String thePreference)
{
SharedPreferences.Editor editor = getSharedPreferences(myPref,0).edit();
editor.putString("myStore", thePreference);
editor.commit();
}
You could call them like this:
writeToPreference("on"); // stores that the preference is "on"
writeToPreference("off"); // stores that the preference is "off"
if (getPreferenceValue().equals("on"))
{
// turn the toggle button on
}
else if (getPreferenceValue().equals("off"))
{
// turn the toggle button off
}
else if (getPreferenceValue().equals("TheDefaultValueIfNoValueFoundOfThisKey"))
{
// a preference has not been created
}
Note: you can do this with boolean, integer, etc.
All you have to do is change the String storing and reading to boolean, or whatever type you want.
Here is a link to a pastie with the code above modified to store a boolean instead: http://pastie.org/8400737
You need to use SharedPreferences to save the settings of your app locally. Refer this link for more details : http://developer.android.com/reference/android/content/SharedPreferences.html
Use SharedPreferences as,
To Save:
SharedPreferences settings;
SharedPreferences.Editor editor;
public static final String PREFS_NAME = "app_pref";
public static final String KEY_p_id = "KEY_test";
settings = getSharedPreferences(PREFS_NAME, 0);
editor = settings.edit();
editor.putString(Login_screen.KEY_test, values.get(0));
editor.commit();
To Remove:
editor.remove("KEY_test").commit();
You should check out SharedPreferences. It's Android's way of persisting simple values. Or you could create a full database.
Use SharedPreferences to save small chunk of app data.
Check the developer's website for this.
Also check out this Tutorial for step by step guide.
You can use local DB like SQlite for for your app.
Related
In one of my views the user makes a selection. I want to store that selection in a variable I can use across all views so it can be used for further database queries such as "bookId".
How can I make "bookId" a global variable that is set on one view and can be accessed across the other views when needed?
----- Edit: What I'm attempting to do based on comments and answers -----
On my main activity where the SharedPreference is stored I have this before the onCreate:
public static final String PREFS_NAME = "myPrefs";
SharedPreferences settings;
Integer bookId;
In my onCreate I've done this:
settings = getSharedPreferences(PREFS_NAME, 0);
bookId = settings.getInt("bookId", 0);
After the button press I'm storing a custom attribute and attempting to set bookId in the SharedPreference:
SharedPreferences.Editor editor = settings.edit();
editor.putInt("bookId",bookKey);
editor.commit();
In another view I'm attempting to get the bookId from the SharedPreference and, for testing purposes, I'm trying to set the stored value to a textView just to make sure it stored and carried over correctly.
Before the onCreate on the second view:
public static final String PREFS_NAME = "myPrefs";
SharedPreferences settings;
Inside the onCreate:
settings = getSharedPreferences(PREFS_NAME, 0);
Integer bookId = settings.getInt("bookId", (Integer) null);
tempBookTextView = (TextView) findViewById(R.id.tempBookTextView);
tempBookTextView.setText(bookId);
I have a two questions, how does this look so far? Any ideas why the app crashes when I use
Integer bookId = settings.getInt("bookId", (Integer) null);
Instead of using global variable to access variable value through out the app try using SharedPreferences.
sample activity:
public class Book extends Activity {
public static final String PREFS_NAME = "MyPrefsFile";
String mBookId = null;
#Override
protected void onCreate(Bundle state){
super.onCreate(state);
. . .
// Restore preferences
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
mBookId = settings.getString("book_id", null);
// use book_id;
}
#Override
protected void onStop(){
super.onStop();
// We need an Editor object to make preference changes.
// All objects are from android.context.Context
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editor = settings.edit();
editor.putString("book_id", mBookId);
// Commit the edits!
editor.commit();
}
}
Preferences are typically created private and can be accessed via all over the application components. Sharing data with other application with world readable or writable preference file is rarely used, as the external component would need to know the exact filename and location of the file.
To kill the spirit of encapsulation,
public class Globals {
public static int x;
public static int y;
}
and later
if (Globals.x == 0) { ... }
But please don't do exactly that, any class can contain static variables, find a class responsible for the value you want to store.
OTOH, android processes may be restarted when you don't expect it, in which case all the variables will be reset. So it's better to use shared preferences and if they don't work as expected (which I have seen in at least one release of Android), store the instance of shared preferences in a static variable.
You can use Shared Preferences
Saved at once !
SharedPreferences.Editor editor = PreferenceManager.getDefaultSharedPreferences(ProjectAct.this).edit();
editor.putInteger(StaticVariable.BOOKID, "1");
p.get("contract_no"));
editor.commit();
Then call from anywhere like that
SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
int book_id = prefs.getInteger(StaticVariable.BOOKID,null);
See more at How to use SharedPreferences in Android to store, fetch and edit values
I want to know if its possible to keep information about an app in a while for example.
I have an app that access this file and get information about the choices that the user have made. For example:
I have a button for many events (event is a model), and i want to know if the user clicked in the button even after the application restarts.
I know that it is possible to keep information about login and password. Is possible to do something like this with other information?
Use Shared Preferences. Like so:
Create these methods for use, or just use the content inside of the methods whenever you want:
public String getPrefValue()
{
SharedPreferences sp = getSharedPreferences("preferenceName", 0);
String str = sp.getString("myStore","TheDefaultValueIfNoValueFoundOfThisKey");
return str;
}
public void writeToPref(String thePreference)
{
SharedPreferences.Editor pref =getSharedPreferences("preferenceName",0).edit();
pref.putString("myStore", thePreference);
pref.commit();
}
You could call them like this:
// when they click the button:
writeToPref("theyClickedTheButton");
if (getPrefValue().equals("theyClickedTheButton"))
{
// they have clicked the button
}
else if (getPrefValue().equals("TheDefaultValueIfNoValueFoundOfThisKey"))
{
// this preference has not been created (have not clicked the button)
}
else
{
// this preference has been created, but they have not clicked the button
}
Explanation of the code:
"preferenceName" is the name of the preference you're referring to and therefore has to be the same every time you access that specific preference. eg: "password", "theirSettings"
"myStore" refers to a specific String stored in that preference and their can be multiple.
eg: you have preference "theirSettings", well then "myStore" could be "soundPrefs", "colourPrefs", "language", etc.
Note: you can do this with boolean, integer, etc.
All you have to do is change the String storing and reading to boolean, or whatever type you want.
You can use SharedPreference to save your data in Android.
To write your information
SharedPreferences preferences = getSharedPreferences("PREF", Context.MODE_PRIVATE);
SharedPreferences.Editor editor = preferences.edit();
editor.putString("user_Id",userid.getText().toString());
editor.putString("user_Password",password.getText().toString());
editor.commit();
To read above information
SharedPreferences prfs = getSharedPreferences("PREF", Context.MODE_PRIVATE);
String username = prfs.getString("user_Id", "");
In iOS NSUserDefaults is used to do the same
//For saving
NSUserDefaults *defaults=[NSUserDefaults standardUserDefaults];
[defaults setObject:your_username forKey:#"user_Id"];
[defaults synchronize];
//For retrieving
NSString *username = [defaults objectForKey:#"user_Id"];
Hope it helps.
I have to change one text with another when user select option from settings,For example
I have to change Kilometers in to miles when user select it from option. And When i select it
i have to change kilometer into Miles thought the application , Please help me if anyone knows
how to do it?
Declare these globally for convenience:
SharedPreferences sharedPrefs;
Editor editor;
private static final String PRIVATE_PREF = "current_selection";
And then in the onCreate() or it's equivalent:
sharedPrefs = getApplicationContext().getSharedPreferences(PRIVATE_PREF, Context.MODE_PRIVATE);
// SET THE DEFAULT VALUE
editor = sharedPrefs.edit();
editor.putString("value", "kilometers");
// DONT SKIP THIS STEP
editor.commit();
Finally, wherever you need to check which of the two is the current selected value (Kilometers / Miles):
String strSetting = sharedPrefs.getString("value", null);
Now, you can use the String strSetting to check the value of the setting, and run the appropriate code. I am assuming it has something to do with conversion perhaps.
NOTE: If you are using the above (retrieving) in another Activity, you will need to instantiate this again:
SharedPreferences sharedPrefs = getApplicationContext().getSharedPreferences(PRIVATE_PREF, Context.MODE_PRIVATE);
String strSetting = sharedPrefs.getString("value", null);
Anytime you want to change the setting, just use the first piece of code. For example, if you change from Kilometers to Miles:
// SET THE A NEW VALUE
editor = sharedPrefs.edit();
editor.putString("value", "miles");
// DONT SKIP THIS STEP
editor.commit();
You can read more about SharedPreferences here
Declare a static String in your MainActivity (or elsewhere).
class MainActivity {
public static String distance = "kilometer";
}
You can change the String from anywhere with
MainActivity.distance = "miles";
Then you can use the distance String allover your app.
i am creating login in my app. User type his info i send it to web service to check and get his ID. Now i need to save it somewhere in my app that i could check if he had login.
So where this info should be saved ? I know that every app have it's settings so there should be this info ? Maybe someone could give me more info what and how this is doing.
Thanks.
I found this post:
What is the most appropriate way to store user settings in Android application
I believe my question was duplicate. But it would be nice if you have something to share more.
First of all save user info like uname & password in SharedPreferences with this code.
SharedPreferences settings = getSharedPreferences("UserInfo", 0);
SharedPreferences.Editor editor = settings.edit();
editor.putString("Username",txtUname.getText().toString());
editor.putString("Password",txtPWD.getText().toString());
editor.commit();
and then get SharedPreferences from below code
SharedPreferences settings = getSharedPreferences("UserInfo", 0);
txtUname.setText(settings.getString("Username", "").toString());
txtPWD.setText(settings.getString("Password", "").toString());
Answer is Use Application Class or Shared Preferences
I assume you can easily search for the Example of Application Class, SharedPreferences and SQLite Database
So I am mentioning Where Do I Use Which Options
Application Class
When I got anything(var , array , list , objects) to store just only for the LifeTime of the Application..and As it got close (for Android Force Close) I use Application Class.
SharedPreferences
I use this when I got some short information like id,token,username,flags and I want to store that as long as the application rest in the Device..and need to use those information everytime I start the Application..
SQLite Database
When there is a bulk data in Record format (Row - Column) I used it to store in database so it becomes easy to store , retrive and manipulate.
You can use SharedPreferences for this.
Some codes from references (taken from documentation):
public class Calc extends Activity {
public static final String PREFS_NAME = "MyPrefsFile";
#Override
protected void onCreate(Bundle state){
super.onCreate(state);
. . .
// Restore preferences
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
boolean silent = settings.getBoolean("silentMode", false);
setSilent(silent);
}
#Override
protected void onStop(){
super.onStop();
// We need an Editor object to make preference changes.
// All objects are from android.context.Context
SharedPreferences settings = getSharedPreferences(PREFS_NAME, 0);
SharedPreferences.Editor editor = settings.edit();
editor.putBoolean("silentMode", mSilentMode);
// Commit the edits!
editor.commit();
}
}
if user clear the application data from setting -> application manager -> your application -> clear data
then all data saved in shared preferences will get removed
i need to save a simple field to configurate my APP, cause this, i wont use a database (it's only a field...), i need to save true or false value for this field on a file, and everytimes a section of my app wanna check if it is true they have to check this textfile, and not to open a connexion to a database
i need to save the config for ever... i mean that when i exit from my app, and for example, i shut down my android device, when i start my device again and start my app, the config have to be saved
is this possible? how can i do it? i can't find any information about that
EDIT: i have problems with the first answer... this code is on my oncreate method:
static SharedPreferences settings;
static SharedPreferences.Editor configEditor;
settings = this.getPreferences(MODE_WORLD_WRITEABLE);
if (settings.getBoolean("showMeCheckBox", true))
showMeCheckBox.setChecked(true);
else
showMeCheckBox.setChecked(false);
applyButton.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
// Perform action on clicks
if (showMeCheckBox.isChecked()) {
configEditor.putBoolean("showMeCheckBox", true);
} else {
configEditor.putBoolean("showMeCheckBox", false);
}
}
});
ok, but this doesn't works... allways is selected... always true, like the default value... doesn't matter if i checked or unchecked it.... :S
i suggest not to use a textfile but the Preference Editor.
static SharedPreferences settings;
static SharedPreferences.Editor editor;
settings = this.getPreferences(MODE_WORLD_WRITEABLE);
editor = settings.edit();
//store value
editor.putString("Preference_name_1", "1");
//get value
//eill return "0" if preference not exists, else return stored value
String val = settings.getString("Preference_name_1", "0");
Edit: you have to initialize the configEditor and after setting a value, you have to commit
editor = settings.edit();
editor.putBoolean("name",true);
editor.commit();