I have two arrays, the first consists of 9 buttons. The second can hold 9 Strings. I have a method called getPlayerChoiceText to populate the String array with the text that is set on each button from the playerchoice Array. How can I save this text using SharedPreferences?
private String[] getPlayerChoiceText()
{
playerchoiceText[0] = playerchoice[0].getText().toString();
playerchoiceText[1] = playerchoice[1].getText().toString();
playerchoiceText[2] = playerchoice[2].getText().toString();
playerchoiceText[3] = playerchoice[3].getText().toString();
playerchoiceText[4] = playerchoice[4].getText().toString();
playerchoiceText[5] = playerchoice[5].getText().toString();
playerchoiceText[6] = playerchoice[6].getText().toString();
playerchoiceText[7] = playerchoice[7].getText().toString();
playerchoiceText[8] = playerchoice[8].getText().toString();
return playerchoiceText;
}
private void saveData()
{
SharedPreferences sharedPreferences = getSharedPreferences(SHARED_PREFS, MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
playerchoiceText = getPlayerChoiceText();
}
I have got the same problem. I solved it by using JSONArray.
JSONArray choices = new JSONArray();
choices.put("1");
choices.put("2");
choices.put("3");
// Save
SharedPreferences sharedPreferences = getSharedPreferences(SHARED_PREFS, MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putString("choices", choices.toString());
// Retrieve
choices = new JSONArray(sharedPreferences.getString("choices", "[]"));
In this way, you can easily do Insert and Delete operations. I hope this helps.
Android's SharedPreferences operates as a key value store, and does not allow you to directly store Java objects. So, representing your player choice text values as a map would make more sense, if you want to store them using shared preferences.
There is one trick you might be able to use here, if you wanted to continue representing your choice texts as an array. You could store the texts using a delimiter, e.g. pipe:
String choices = String.join("|", playerchoiceText);
SharedPreferences prefs = getSharedPreferences(YOUR_PREFS_KEY, Context.MODE_PRIVATE);
prefs.edit().putString("choices", choices).apply();
And then, on the way out:
SharedPreferences prefs = getSharedPreferences(YOUR_PREFS_KEY, Context.MODE_PRIVATE);
String[] playerchoiceText = prefs.getString("choices", "").split("\\|");
Use put/getStringSet():
private void saveData()
{
SharedPreferences sharedPreferences = getSharedPreferences(SHARED_PREFS, MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
String[] playerchoiceText = getPlayerChoiceText();
editor.putStringSet("player_choice", new HashSet<T>(Arrays.asList(playerchoiceText));
editor.commit();
}
Related
I'm new to android programming and I was wondering if it's possible to add more than one value in shared preferences at the same time. I have tried the following, but when I try to get the values I can see only the first one. The other value is getting the default value. Can you help me, please?
My code:
SharedPreferences.Editor editor = getSharedPreferences("prefs", Context.MODE_PRIVATE).edit();
String string1 = "myString1";
String string2 = "myString2";
editor.putString(string1, string2).apply();
SharedPreferences preferences = getSharedPreferences("prefs", Context.MODE_PRIVATE);
String string1FromSP = preferences.getString(string1, "default");
String string2FromSP = preferences.getString(string2, "default");
Log.e("Value 1", string1FromSP);
Log.e("Value 2", string2FromSP);
Values in Android SharedPreference gets stored like Key Value pair. And You are trying to store it all together like list or varargs.
So to save the values in Your example
SharedPreferences.Editor editor = getSharedPreferences("prefs", Context.MODE_PRIVATE).edit();
String string1 = "myString1";
String string2 = "myString2";
editor.putString("STRING_1", string1).apply();
editor.putString("STRING_2", string2).apply();
SharedPreferences preferences = getSharedPreferences("prefs", Context.MODE_PRIVATE);
String string1FromSP = preferences.getString("STRING_1", "default");
String string2FromSP = preferences.getString("STRING_2", "default");
Log.e("Value 1", string1FromSP);
Log.e("Value 2", string2FromSP);
i am new to Android and i try to complete my first android app. I have an arraylist of strings(which i have adapted into a listview) and i add different strings by pressing different buttons. The problem is that when the app closes, the arraylist loses all the data, and i have read that sharedpreferences class can solve this problem.I tried that, and i retrieved the arraylist back, but not with the same order as it was when i saved it. So, how can i retrieve the arraylist with the same order?
Thanks in advance!
the EASIEST way to save arraylist in sharedpreferences is convert it into JSON and 100% in the same order when you get it
String list = new Gson().toJson(your_list);
shared.putString("KEY", list).apply();
then, to convert it back
List<Object> list = new Gson().fromJson(jsonString, new TypeToken<ArraList<Object>>(){}.getType());
If you're really interested on doing that using SharedPreferences instead of a database, you could try to save the Strings using their position on the array as the key on the preferences file.
You can achieve that with the snippet below:
private String prefName = "preferences";
/**
* Save the arraylist of Strings in a preferences file.
*/
public void saveArray(Context context, ArrayList<String> myArray) {
SharedPreferences sharedPref = context.getSharedPreferences(prefName,Context.MODE_PRIVATE);
Editor editor = sharedPref.edit();
for (int i = 0; i < myArray.size(); i++) {
editor.putString(String.valueOf(i), myArray.get(i));
}
editor.commit();
}
/**
* Reads the saved contents in order.
*/
public ArrayList<String> readArray(Context context) {
SharedPreferences sharedPref = context.getSharedPreferences(prefName,Context.MODE_PRIVATE);
Editor editor = sharedPref.edit();
int size = sharedPref.getAll().size();
ArrayList<String> ret = new ArrayList<>();
for (int i = 0; i < myArray.size(); i++) {
ret.add(i,sharedPref.getString(String.valueOf(i)));
}
return ret;
}
The preference file should look something like this:
<?xml version='1.0' encoding='utf-8' standalone='yes' ?>
<map>
<string name="0">My String</string>
<string name="1">My second String</string>
</map>
I want to know how to take a simple string that is being saved in shared preferences but then save each one of those strings and display them into an array list. The user will save the string once a day. And I want the strings to display as an array list. Here's the code for what I'm working with. I have "physical_fragment.java"(SAVES THE DATA) & "MainActivity.java"(LOADS THE DATA).
PHSYICAL_FRAGMENT.JAVA
public void save(View view){
Date date = new Date();
String stringDate = DateFormat.getDateInstance().format(date);
SharedPreferences sharedPreferences = getSharedPreferences("MyData", Context.MODE_PRIVATE);
SharedPreferences.Editor editor =sharedPreferences.edit();
editor.putString("result",String.format(stringDate, date) + " - " + text_view5.getText().toString());
editor.commit();
Toast.makeText(this, "Saved successfully!", Toast.LENGTH_LONG).show();
}
MAINACTIVITY.JAVA
resultPhysical= (TextView) findViewById(R.id.home);
SharedPreferences sharedPreferences = getSharedPreferences("MyData", Context.MODE_PRIVATE);
String result= sharedPreferences.getString("result",DEFAULT);
if (result.equals(DEFAULT))
{
Toast.makeText(this, "No data found", Toast.LENGTH_LONG).show();
}
else
Toast.makeText(this, "Load Successful", Toast.LENGTH_LONG).show();
resultPhysical.setText(result);
}
I'd say use GSON for that.
To convert a list of strings to JSON to be stored in preferences you use this:
List<String> list = ...
Type type = new TypeToken<List<String>>(){}.getType();
String json = gson.toJson(list, type);
and store json in SharedPreferences using putString.
To read from SharedPreferences you use something like this:
String result = sharedPreferences.getString("result", DEFAULT);
Type type = new TypeToken<List<String>>(){}.getType();
List<String> list = gson.fromJson(result, type);
you can do as follows:
SharedPreferences sharedPreferences = getSharedPreferences("MyData", Context.MODE_PRIVATE);
SharedPreferences.Editor editor =sharedPreferences.edit();
ArratList<String> dataList;
String data = "";
for(String itemData:dataList){
data = itemData + String.format(stringDate, date) + " - " + text_view5.getText().toString()+ "/";
editor.putString(data);
}
editor.commit();
Now get the string from Shared preference and split it.
String result= sharedPreferences.getString("result",DEFAULT);
String[] splited = str.split("/");
This helps with out having support of Libraries which can effect size of apk file
I am building an android application where the user selects his event from spinner tool.
The Spinner tool displays the array list that user had selected first time the application is launched.
Now I had parsed the array list from app launch page to spinner activity class an using it in spinner tool success full now.
Here is code:
public static ArrayList<String> array;
Here, the name array has the arraylist.
I need to store this in sharedprefrences. How can I do this ?
I am new to android.
I don't suggest using putStringSet() since it will screw up your arrayorder.
I suggest running a for loop over your array and giving them different key names. + in the end adding another String, that tells you how long the array is once you wanna read out the strings of the SharedPreferences.
General settings:
SharedPreferences sharedPreferences = getSharedPreferences("YOURKEYFILE", Activity.MODE_PRIVATE);
SharedPreferences.Editor sharedPreferencesEditor = sharedPreferences.edit();
Save String Array:
for (int i = 0; i < array.size(); i++) {
sharedPreferencesEditor.putString("StringArrayElement" +i, array.get(i));
}
sharedPreferencesEditor.putInt("StringArrayLength", array.size());
sharedPreferencesEditor.commit();
Read String Array:
array.clear();
for (int i = 0; i < sharedPreferencesEditor.getInt("StringArrayLength", 0) {
array.add(sharedPreferencesEditor.getString("StringArrayElement" +i, "");
}
NOTE:
The above code is untested! Community correct me there if you find mistakes.
You can save your array as Serializable object.
//save the task list to preference
SharedPreferences prefs = getSharedPreferences(SHARED_PREFS_FILE, Context.MODE_PRIVATE);
Editor editor = prefs.edit();
try {
editor.putString(ARRAY, ObjectSerializer.serialize(array));
} catch (IOException e) {
e.printStackTrace();
}
editor.commit();
And to retrieve it from SharedPreferences:
SharedPreferences prefs = getSharedPreferences(SHARED_PREFS_FILE, Context.MODE_PRIVATE);
try {
array = (ArrayList<String>) ObjectSerializer.deserialize(prefs.getString(ARRAY,
ObjectSerializer.serialize(new ArrayList<String>())));
} catch (IOException e) {
e.printStackTrace();
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
You can get ObjectSerializer.java from here
This code help to you maybe.You save list item by counter i.
for(int i=0;i<list.size();i++)
{
editor.putString(list.get(i)+i, list.get(i));
editor.commit();}
for(int i=0;i<list.size();i++)
{
preferences.getString(list.get(i)+i, "");
}
It's better to go with Set<String> as API version 11 introduced methods putStringSet and getStringSet which allows the developer to store a list of string values and retrieve a list of string values, respectively.
Save list
// Save the list.
editor.putStringSet("array", myStrings);
editor.commit();
Fetch list
// Get the current list.
SharedPreferences settings = this.getSharedPreferences("YourActivityPreferences", Context.MODE_PRIVATE);
SharedPreferences.Editor editor = settings.edit();
Set<String> myStrings = settings.getStringSet("array", new HashSet<String>());
Here is the code where I put the values:
if(soundima == 1){
soundima=0;
editor.putInt("sOn", soundima);
editor.commit();
}
else if(soundima == 0){
soundima=1;
editor.putInt("sOn", soundima);
editor.commit();
}
Then when I quit the application, the values are not remembered. I get the values with this code:
editor = PreferenceManager.getDefaultSharedPreferences(this);
soundima = editor.getInt("sOn", 0);
I am not entirely sure why that is not working. However, the following code should solve the problem.
//create a constant to use for the shared preferences
public static final String YOUR_CONSTANT = "Preferences";
Then to place the values in shared preferences, use the following code:
if(soundima == 1){
soundima = 0;
SharedPreferences sound = getSharedPreferences(YOUR_CONSTANT,0);
SharedPreferences.Editor editor = sound.edit();
editor.putInt("sOn", soundima);
editor.commit();
}
else if(soundima == 0){
soundima = 1;
SharedPreferences sound = getSharedPreferences(YOUR_CONSTANT,0);
SharedPreferences.Editor editor = sound.edit();
editor.putInt("sOn", soundima);
editor.commit();
}
Then to retrieve the values, use this code:
SharedPreferences sound = getSharedPreferences(YOUR_CONSTANT,0);
soundima = sound.getInt("sOn", 0);