Save An Array Of Booleans Using Shared Preference

I have a long list of booleans which i want to save In my app using shared preference, so that i can save the state of a number of checkboxes. i have tried a few approaches now, a

Solution 1:

In order to save an array of booleans to memory, I suggest you build a string from the booleans as follows:

Initialization

privateboolean[] checkState;
private Editor mEditPrefs;
private SharedPreferences mPreferences;
//initialize checkState array and mEditPrefs and mPreferences

Save the array

Stringsave="";
for (intn=0; n < checkState.length; n++) {
    if (checkState[n] != null) {
                if(checkState[n]) {
                    save = save + "true" + "|$|SEPARATOR|$|";
                } else {
                    save = save + "false" + "|$|SEPARATOR|$|";
                }
    }
}
mEditPrefs.putString("memory", save);
mEditPrefs.commit();

Get the Array

String mem = mPreferences.getString("memory", "");
mEditPrefs.putString("memory", "");
String[] array = getArray(mem); //see below for the getArray() method
checkState = newboolean[array.length];
for(int n = 0; n < array.length; n++){
    if(array[n].equals("true"){
        checkState[n] = true;
    } else {
        checkState[n] = false;
    }
}

the getArray() method

publicstaticString[] getArray(String input) {
    return input.split("\\|\\$\\|SEPARATOR\\|\\$\\|");
}

This isn't an elegent solution, but SharedPreferences doesn't support storing arrays, so the only way to store an array is to make a long string separated by a discernible separator (in this case |$|SEPARATOR|$| ) that won't be confused with the data you are storing. Also, since there's no way to store arrays, I converted the booleans to strings before storing them and then I retrieve them from memory and detect if it is "true" or "false" and set the checkState array accordingly.

Hope this helped. I use a very similar process for storing an array of URLs and it works perfectly.

Alternatively you could use an SQLiteDatabase to store your array, but that might be a little too much work just to store some booleans.

EDIT: Originally I thought that toString() would work on a boolean, but apparently not on an array.