Flashcards Test/Memorization in Andoird Studio/Kotlin - arrays

Question

Sorry for the long post! I am trying to make a memorization flashcard and I have been stuck with this for a week
Here is the array
val sentenceArray = arrayOfNulls<String>(8)
sentenceArray[0] = ""
sentenceArray[1] = "Array 1 (1)"
sentenceArray[2] = "Array 2 (2)"
sentenceArray[3] = "Array 3 (3)"
sentenceArray[4] = "Array 4 (4)"
sentenceArray[5] = "Array 5 (5)"
This is the code. To generate the test there are 2 spinners (left and right) If the user selected 1 for the left spinner and 3 on the right spinner then it will only display Array 1 to 3 each time the user clicks on textView
leftSpinner.onItemSelectedListener = object : AdapterView.OnItemSelectedListener
{
override fun onNothingSelected(parent: AdapterView<*>?) {}
override fun onItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long)
{
//Stores value of the selected Left Spinner
val selectedLeftSpinner = leftSpinner.getItemAtPosition(position).toString()
rightSpinner.onItemSelectedListener = object : AdapterView.OnItemSelectedListener
{
override fun onNothingSelected(parent: AdapterView<*>?) {}
override fun onItemSelected(parent: AdapterView<*>?, view: View?, position: Int, id: Long)
{
//Actions when buttonStart is clicked
buttonStart.setOnClickListener {
//Stores value of the selected Right Spinner
val selectedRightSpinner = rightSpinner.getItemAtPosition(position).toString()
//Stores selectedLeftSpinner value to firstSentence so that it can be used
var firstSentence = selectedLeftSpinner.toInt()
//Stores selectedRightSpinner value to lastSentence so that it can be used
val lastSentence = selectedRightSpinner.toInt()
//Displays (1)
textView.text = sentenceArray[firstSentence]?.takeLast(3)
//Waiting for an action on the TextView
textView.setOnClickListener {
//Displays (Array 1)
textView.text = sentenceArray[firstSentence]
//Waiting for an action on the TextView
textView.setOnClickListener {
while (firstSentence < lastSentence) {
//This while loop displays Array 1 to 5 each time a user clicks on textView
firstSentence++
textView.text = sentenceArray[firstSentence]
//Ends the test when it reaches the last array
if (firstSentence == lastSentence) {
buttonStart.text = "DONE"
}
break
}
}
}
}
}
}
}
}
What I am trying to do:
After the user selected a value from the left spinner (for example 1) and right spinner (for example 3) They would click on the buttonStart to start the flashcard. The textView starts off displaying a (1). To reveal the answer, they could click on textView and then it will display "Array 1" They would then click on textView and it will display a (2)... etc
So the flow should be like this, after clicking on textView on each step
(1)
Array 1
(2)
Array 2
(3)
Arra3 3
DONE
With my current while loop
while (firstSentence < lastSentence) {
//This loop displays Array 1 to 5 each time a user clicks on textView
firstSentence++
textView.text = sentenceArray[firstSentence]
//Ends the test when it reaches the last aya
if (firstSentence == lastSentence) {
buttonStart.text = "DONE"
}
break
}
This is the current flow
(1)
Array 1
Array 2
Array 3
DONE
I have tried a lot of things but I could not get it to work and I have no idea way
Here are 2 different codes that I tried that did not work. This was inside the while loop
textView.setOnClickListener {
if (textView.text == sentenceArray[firstSentence])
textView.text = sentenceArray[firstSentence]?.takeLast(3)
}
and this code
if (firstSentence < lastSentence)
{
textView.setOnClickListener {
textView.text = sentenceArray[firstSentence]?.takeLast(3)
}
}
The 2 codes result into this flow
(1)
Array 1
Array 2
(2)
DONE when its supposed to continue to (3)

Answer 1

Your dont really need a loop, since looping is handled by the user clicking the text view, in your case an if condition will suffice.
One other thing that I observed is that you are setting up your click listeners and spinner listeners inside other listeneres. this is not required and makes your code unreadable and complex to parse, Please note that in your case you can define all the listeners on the same level to achieve what you want, you dont have to nest them.
You can do something as following. I have lifted out the nested listener configuration.
class Temp {
lateinit var leftSpinner: Spinner
lateinit var rightSpinner: Spinner
lateinit var buttonStart: Button
lateinit var sentenceArray: Array<String>
lateinit var textView: TextView
var selectedLeftSpinner = -1
var selectedRightSpinner = -1
private fun setup() {
/** Define left spinner item selected listener, capture the selected position */
leftSpinner.onItemSelectedListener = object : AdapterView.OnItemSelectedListener {
override fun onNothingSelected(parent: AdapterView<*>?) {}
override fun onItemSelected(
parent: AdapterView<*>?, view: View?,
position: Int, id: Long) {
selectedLeftSpinner = position
}
}
/** Define right spinner item selected listener, capture the selected position */
rightSpinner.onItemSelectedListener = object : AdapterView.OnItemSelectedListener {
override fun onNothingSelected(parent: AdapterView<*>?) {}
override fun onItemSelected(
parent: AdapterView<*>?, view: View?,
position: Int, id: Long) {
selectedRightSpinner = position
}
}
/** Define button start click listener, show text if left spinner is selected. */
buttonStart.setOnClickListener {
/** only set text if left spinner is selecte */
if(selectedLeftSpinner != -1){
textView.text = sentenceArray[selectedLeftSpinner]?.takeLast(3)
}
}
/** Handle edge cases, such as what happens if spinner is not selected */
textView.setOnClickListener {
/** if currently selected item's last 3 chars are being shown,
* then show the answer.
*/
if(textView.text == sentenceArray[selectedLeftSpinner]?.takeLast(3)){
textView.text = sentenceArray[selectedLeftSpinner]
}
/** if answer is being shown then show last three chars of next item */
else if(selectedLeftSpinner < selectedRightSpinner){
selectedLeftSpinner++
textView.text = sentenceArray[selectedLeftSpinner]?.takeLast(3)
}
/** else we have reached the last item */
else{
buttonStart.text = "DONE"
/** reset left spinner to not selected state */
selectedLeftSpinner = -1
}
}
}
}
This should work but I have not considered any edge cases, so you will have to take care of them and there is space for other improvments such as usig a key, value structure(ex map) to store your flash card question and answers an code can still be reduced as both of listeners for spinners are identical, I leave it as an exercise.