Use SharedPreferences to store more than one “favorite”

Question

I am making a quotes application, and I am using shared prefrences to store a users favorite quotes. I know I can use SQL but I am sticking with shared prefrences for the time being. This is how I am saving a favorite quote:

if(view.getId()==R.id.favoritesBtn){
        String stringData = quote.getText().toString();


        SharedPreferences.Editor editor = someData.edit();
        editor.putString("quote_string", stringData);
        editor.commit();

    }
    if(view.getId()==R.id.button){
        someData=getSharedPreferences(filename,0);
        String dataReturned = someData.getString("quote_string", "Couldn't Load Data");
        dataResults.setText(dataReturned);

    }

dataResults is of course the textview where the saved quote is displayed. Now, my question comes when I try to save another quote. The first saved quote is overwritten, and each time the user only sees his last "saved" quote. How can I make it so that the user can see all quotes he pressed the "favoritesBtn" on?

Answer 1

In your example you are only saving the most recent quote. You can use putStringSet() so save a Set of Strings in SharedPreferences. Another possible way would be to store the Quotes in a file if you need to preserve the order.

Answer 2

First thing is first: This is really a job for an sql database (especially since you can save multiple values)

Now to actually answer your question:

You have a couple options here.

You can use putStringSet() to put a full set of quotes in the preference

You can iterate over all shared preferences

Save your favorite "quote_string" as a delimited format

String quotes = someData.getString("quote_string", "");
quotes = quotes + "|" + <new quote>;
editor.put("quote_string", quotes);
//more code
String dataReturned = someData.getString("quote_string", "");
String[] separatedQuotes = dataReturned.split("|");

Save a preference as well pointing to quote preference names:

String quoteNames = someData.getString("quote_names", "");
if (quoteNames.length() > 0)
    quoteNames += "," + <quote_name>
quoteNames = "quote" + quoteNames.split("|").length;
editor.put("quote_names", quoteNames);
//more code
String dataReturned = someData.getString("quote_names", "");
String[] separatedQuoteNames = dataReturned.split("|");
for (String separatedQuoteName: separatedQuoteNames) {
    String quote = someData.getString(separatedQuoteName, "No Data:);
}

Obviously depending on your goal some options might be better than others.

Answer 3

Use putStringSet() for that:

Set<String> quotes = someData.getStringSet("quote_string", new HashSet<String>());
quotes.add(stringData);
SharedPreferences.Editor editor = someData.edit();
editor.clear();
editor.putStringSet("quote_string", quotes);
editor.commit();