Android: SQLite saving string array?

You cannot save String array into Database. But you can use this trick.

1) So you have to convert it into simple String using convertArrayToString(String[] array) method. This will concatenate all elements of string using ‘comma’.

2) When you would retrieve this String back from Database you could convert it back to String array using convertStringToArray(String str) method. This method will split the string from ‘comma’ and you will get your original array back.

public static String strSeparator = "__,__";
public static String convertArrayToString(String[] array){
    String str = "";
    for (int i = 0;i<array.length; i++) {
        str = str+array[i];
        // Do not append comma at the end of last element
        if(i<array.length-1){
            str = str+strSeparator;
        }
    }
    return str;
}
public static String[] convertStringToArray(String str){
    String[] arr = str.split(strSeparator);
    return arr;
}

Based on Muhammed’s answer but handles List of Strings instead of array and uses StringBuilder instead of allocating many Strings during values concatenation:

private static final String LIST_SEPARATOR = "__,__";

public static String convertListToString(List<String> stringList) {
    StringBuilder stringBuilder = new StringBuffer();
    for (String str : stringList) {
        stringBuilder.append(str).append(LIST_SEPARATOR);
    }

    // Remove last separator
    stringBuilder.setLength(stringBuilder.length() - LIST_SEPARATOR.length());

    return stringBuilder.toString();
}

public static List<String> convertStringToList(String str) {
    return Arrays.asList(str.split(LIST_SEPARATOR));
}

Convert it to single String to save it in sqlite.
Later, retrieve it back from sqlite as a single string and convert it back to Array of String.

String ARRAY_DIVIDER = "#a1r2ra5yd2iv1i9der";

public String serialize(String content[]){      
    return TextUtils.join(ARRAY_DIVIDER, content);
}

public String[] derialize(String content){
    return content.split(ARRAY_DIVIDER);
}

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