How to save a list with Boolean values in SharedPreferences in kotlin?-CodePudding

I want to save this list in SharedPreferences with Boolean values:

val listTheme = mutableListOf( false,false,true,false)

how can this be done? in kotlin language in android studio

CodePudding user response：

You can use the Kotlin Serialization library to store data structures (including classes and lists) as JSON strings - there are other libraries too. But for something simple like this, you can probably get away with doing it yourself:

val listTheme = mutableListOf(false, false, true, false)

// convert each value to a specific character (produces a string)
val serialized = listTheme.map { if (it) '1' else '0' }.joinToString("")

// convert each character to a true or false value (produces a list)
val deserialized = serialized.map { it == '1' }

print(" original: $listTheme\n serialized: $serialized\n deserialized: $deserialized")

>>>  original: [false, false, true, false]
 serialized: 0010
 deserialized: [false, false, true, false]

Then you can just throw it in a String preference, and convert it back to a list when you fetch it later.