Refactor CountryAutoCompleteTextView logic (#1828)

- Create `Country` model to use in `CountryAutoCompleteTextView`
  and `CountryAdapter` to simplify logic
- Make `CountryAutoCompleteTextView.selectedCountry` non-null
- Avoid redundant `setText()` calls in `CountryAutoCompleteTextView`
  after a user selects a dropdown item
- Make `CountryAutoCompleteTextView.CountryChangeListener` a
  function type `(Country) -> Unit`

stripe/src/main/java/com/stripe/android/view/Country.kt

@@ -0,0 +1,12 @@
+package com.stripe.android.view
+
+internal data class Country(
+    val code: String,
+    val name: String
+) {
+
+    /**
+     * @return display value for [CountryAutoCompleteTextView] text view
+     */
+    override fun toString(): String = name
+}

stripe/src/main/java/com/stripe/android/view/CountryAdapter.kt

@@ -18,20 +18,20 @@ import java.util.Locale
  */
 internal class CountryAdapter(
     context: Context,
-    initialCountries: List<String>
-) : ArrayAdapter<String>(context, R.layout.country_text_view) {
+    initialCountries: List<Country>
+) : ArrayAdapter<Country>(context, R.layout.country_text_view) {
     private val countryFilter: Filter = CountryFilter(
         initialCountries,
         this,
         context as? Activity
     )
-    private var suggestions: List<String> = initialCountries
+    private var suggestions: List<Country> = initialCountries
 
     override fun getCount(): Int {
         return suggestions.size
     }
 
-    override fun getItem(i: Int): String {
+    override fun getItem(i: Int): Country {
         return suggestions[i]
     }
 
@@ -41,12 +41,12 @@ internal class CountryAdapter(
 
     override fun getView(i: Int, view: View?, viewGroup: ViewGroup): View {
         return if (view is TextView) {
-            view.text = getItem(i)
+            view.text = getItem(i).name
             view
         } else {
             val countryText = LayoutInflater.from(context).inflate(
                 R.layout.country_text_view, viewGroup, false) as TextView
-            countryText.text = getItem(i)
+            countryText.text = getItem(i).name
             countryText
         }
     }
@@ -56,7 +56,7 @@ internal class CountryAdapter(
     }
 
     private class CountryFilter(
-        private val initialCountries: List<String>,
+        private val initialCountries: List<Country>,
         private val adapter: CountryAdapter,
         activity: Activity?
     ) : Filter() {
@@ -74,10 +74,10 @@ internal class CountryAdapter(
             constraint: CharSequence?,
             filterResults: FilterResults?
         ) {
-            val suggestions = filterResults?.values as List<String>
+            val suggestions = filterResults?.values as List<Country>
 
             activityRef.get()?.let { activity ->
-                if (suggestions.any { it == constraint }) {
+                if (suggestions.any { it.name == constraint }) {
                     hideKeyboard(activity)
                 }
             }
@@ -86,7 +86,7 @@ internal class CountryAdapter(
             adapter.notifyDataSetChanged()
         }
 
-        private fun filteredSuggestedCountries(constraint: CharSequence?): List<String> {
+        private fun filteredSuggestedCountries(constraint: CharSequence?): List<Country> {
             val suggestedCountries = getSuggestedCountries(constraint)
 
             return if (suggestedCountries.isEmpty() || isMatch(suggestedCountries, constraint)) {
@@ -96,17 +96,17 @@ internal class CountryAdapter(
             }
         }
 
-        private fun getSuggestedCountries(constraint: CharSequence?): List<String> {
+        private fun getSuggestedCountries(constraint: CharSequence?): List<Country> {
             return initialCountries
                 .filter {
-                    it.toLowerCase(Locale.ROOT).startsWith(
+                    it.name.toLowerCase(Locale.ROOT).startsWith(
                         constraint.toString().toLowerCase(Locale.ROOT)
                     )
                 }
         }
 
-        private fun isMatch(countries: List<String>, constraint: CharSequence?): Boolean {
-            return countries.size == 1 && countries[0] == constraint.toString()
+        private fun isMatch(countries: List<Country>, constraint: CharSequence?): Boolean {
+            return countries.size == 1 && countries[0].name == constraint.toString()
         }
 
         private fun hideKeyboard(activity: Activity) {

stripe/src/main/java/com/stripe/android/view/CountryAutoCompleteTextView.kt

@@ -23,74 +23,74 @@ internal class CountryAutoCompleteTextView @JvmOverloads constructor(
      * @return 2 digit country code of the country selected by this input.
      */
     @VisibleForTesting
-    var selectedCountryCode: String? = null
+    var selectedCountry: Country
 
-    private var countryChangeListener: CountryChangeListener? = null
+    @JvmSynthetic
+    internal var countryChangeCallback: (Country) -> Unit = {}
 
     init {
         View.inflate(getContext(), R.layout.country_autocomplete_textview, this)
-        countryAutocomplete = findViewById(R.id.autocomplete_country_cat)
+
         val countryAdapter = CountryAdapter(
             getContext(),
             CountryUtils.getOrderedCountries(
                 ConfigurationCompat.getLocales(context.resources.configuration)[0]
             )
         )
+
+        countryAutocomplete = findViewById(R.id.autocomplete_country_cat)
         countryAutocomplete.threshold = 0
         countryAutocomplete.setAdapter(countryAdapter)
-        countryAutocomplete.onItemClickListener = AdapterView.OnItemClickListener { _, _, _, _ ->
-            val countryEntered = countryAutocomplete.text.toString()
-            updateUiForCountryEntered(countryEntered)
-        }
-        val defaultCountryEntered = countryAdapter.getItem(0)
-        updateUiForCountryEntered(defaultCountryEntered)
-        countryAutocomplete.setText(defaultCountryEntered)
+        countryAutocomplete.onItemClickListener =
+            AdapterView.OnItemClickListener { _, _, position, _ ->
+                updatedSelectedCountryCode(countryAdapter.getItem(position))
+            }
         countryAutocomplete.onFocusChangeListener = OnFocusChangeListener { _, focused ->
-            val countryEntered = countryAutocomplete.text.toString()
             if (focused) {
                 countryAutocomplete.showDropDown()
             } else {
+                val countryEntered = countryAutocomplete.text.toString()
                 updateUiForCountryEntered(countryEntered)
             }
         }
+
+        val initialCountry = countryAdapter.getItem(0)
+        countryAutocomplete.setText(initialCountry.name)
+        selectedCountry = initialCountry
+        countryChangeCallback(initialCountry)
     }
 
     /**
      * @param countryCode specify a country code to display in the input. The input will display
      * the full country display name.
      */
-    fun setCountrySelected(countryCode: String?) {
-        if (countryCode == null) {
-            return
-        }
+    internal fun setCountrySelected(countryCode: String) {
         updateUiForCountryEntered(getDisplayCountry(countryCode))
     }
 
-    fun setCountryChangeListener(countryChangeListener: CountryChangeListener?) {
-        this.countryChangeListener = countryChangeListener
-    }
-
     @VisibleForTesting
-    fun updateUiForCountryEntered(displayCountryEntered: String?) {
-        val displayCountry = CountryUtils.getCountryCode(displayCountryEntered)?.let {
-            if (selectedCountryCode == null || selectedCountryCode != it) {
-                selectedCountryCode = it
-                countryChangeListener?.onCountryChanged(it)
-            }
+    internal fun updateUiForCountryEntered(displayCountryEntered: String) {
+        val country = CountryUtils.getCountryByName(displayCountryEntered)
+
+        // If the user-typed country matches a valid country, update the selected country
+        // Otherwise, revert back to last valid country if country is not recognized.
+        val displayCountry = country?.let {
+            updatedSelectedCountryCode(it)
             displayCountryEntered
-        } ?: selectedCountryCode?.let {
-            // Revert back to last valid country if country is not recognized.
-            getDisplayCountry(it)
-        }
+        } ?: selectedCountry.name
 
         countryAutocomplete.setText(displayCountry)
     }
 
-    private fun getDisplayCountry(countryCode: String): String {
-        return Locale("", countryCode).displayCountry
+    private fun updatedSelectedCountryCode(country: Country) {
+        if (selectedCountry != country) {
+            selectedCountry = country
+            countryChangeCallback(country)
+        }
     }
 
-    internal interface CountryChangeListener {
-        fun onCountryChanged(countryCode: String)
+    private fun getDisplayCountry(countryCode: String): String {
+        return CountryUtils.getCountryByCode(countryCode)?.name
+            ?: Locale("", countryCode).displayCountry
     }
 }

stripe/src/main/java/com/stripe/android/view/CountryUtils.kt

@@ -4,34 +4,42 @@ import java.util.Locale
 
 internal object CountryUtils {
 
-    private val NO_POSTAL_CODE_COUNTRIES =
-        arrayOf("AE", "AG", "AN", "AO", "AW", "BF", "BI", "BJ", "BO", "BS", "BW", "BZ", "CD", "CF", "CG", "CI", "CK", "CM", "DJ", "DM", "ER", "FJ", "GD", "GH", "GM", "GN", "GQ", "GY", "HK", "IE", "JM", "KE", "KI", "KM", "KN", "KP", "LC", "ML", "MO", "MR", "MS", "MU", "MW", "NR", "NU", "PA", "QA", "RW", "SB", "SC", "SL", "SO", "SR", "ST", "SY", "TF", "TK", "TL", "TO", "TT", "TV", "TZ", "UG", "VU", "YE", "ZA", "ZW")
-    private val NO_POSTAL_CODE_COUNTRIES_SET = setOf(*NO_POSTAL_CODE_COUNTRIES)
-
-    private val COUNTRY_NAMES_TO_CODES: Map<String, String>
-        get() {
-            return Locale.getISOCountries()
-                .associateBy { Locale("", it).displayCountry }
+    private val NO_POSTAL_CODE_COUNTRIES = setOf(
+        "AE", "AG", "AN", "AO", "AW", "BF", "BI", "BJ", "BO", "BS", "BW", "BZ", "CD", "CF", "CG",
+        "CI", "CK", "CM", "DJ", "DM", "ER", "FJ", "GD", "GH", "GM", "GN", "GQ", "GY", "HK", "IE",
+        "JM", "KE", "KI", "KM", "KN", "KP", "LC", "ML", "MO", "MR", "MS", "MU", "MW", "NR", "NU",
+        "PA", "QA", "RW", "SB", "SC", "SL", "SO", "SR", "ST", "SY", "TF", "TK", "TL", "TO", "TT",
+        "TV", "TZ", "UG", "VU", "YE", "ZA", "ZW"
+    )
+
+    private val COUNTRIES: List<Country> =
+        Locale.getISOCountries().map { code ->
+            Country(code, Locale("", code).displayCountry)
         }
 
     @JvmSynthetic
-    internal fun getCountryCode(countryName: String?): String? {
-        return COUNTRY_NAMES_TO_CODES[countryName]
+    internal fun getCountryByName(countryName: String): Country? {
+        return COUNTRIES.firstOrNull { it.name == countryName }
+    }
+
+    @JvmSynthetic
+    internal fun getCountryByCode(countryCode: String): Country? {
+        return COUNTRIES.firstOrNull { it.code == countryCode }
     }
 
     @JvmSynthetic
-    internal fun getOrderedCountries(currentLocale: Locale): List<String> {
+    internal fun getOrderedCountries(currentLocale: Locale): List<Country> {
         // Show user's current locale first, followed by countries alphabetized by display name
-        return listOf(currentLocale.displayCountry)
+        return listOfNotNull(getCountryByCode(currentLocale.country))
             .plus(
-                COUNTRY_NAMES_TO_CODES.keys.toList()
-                    .sortedWith(compareBy { it.toLowerCase(Locale.ROOT) })
-                    .minus(currentLocale.displayCountry)
+                COUNTRIES
+                    .sortedBy { it.name.toLowerCase(Locale.ROOT) }
+                    .filterNot { it.code == currentLocale.country }
             )
     }
 
     @JvmSynthetic
     internal fun doesCountryUsePostalCode(countryCode: String): Boolean {
-        return !NO_POSTAL_CODE_COUNTRIES_SET.contains(countryCode)
+        return !NO_POSTAL_CODE_COUNTRIES.contains(countryCode)
     }
 }

stripe/src/main/java/com/stripe/android/view/ShippingInfoWidget.kt

@@ -61,7 +61,7 @@ class ShippingInfoWidget @JvmOverloads constructor(
         get() {
             val address = Address.Builder()
                 .setCity(cityEditText.text?.toString())
-                .setCountry(countryAutoCompleteTextView.selectedCountryCode)
+                .setCountry(countryAutoCompleteTextView.selectedCountry.code)
                 .setLine1(addressEditText.text?.toString())
                 .setLine2(addressEditText2.text?.toString())
                 .setPostalCode(postalCodeEditText.text?.toString())
@@ -136,9 +136,7 @@ class ShippingInfoWidget @JvmOverloads constructor(
         optionalShippingInfoFields = optionalAddressFields.orEmpty()
         renderLabels()
 
-        countryAutoCompleteTextView.selectedCountryCode?.let { selectedCountryCode ->
-            renderCountrySpecificLabels(selectedCountryCode)
-        }
+        countryAutoCompleteTextView.selectedCountry.let(::renderCountrySpecificLabels)
     }
 
     /**
@@ -149,9 +147,7 @@ class ShippingInfoWidget @JvmOverloads constructor(
         hiddenShippingInfoFields = hiddenAddressFields.orEmpty()
         renderLabels()
 
-        countryAutoCompleteTextView.selectedCountryCode?.let { selectedCountryCode ->
-            renderCountrySpecificLabels(selectedCountryCode)
-        }
+        countryAutoCompleteTextView.selectedCountry.let(::renderCountrySpecificLabels)
     }
 
     /**
@@ -193,7 +189,7 @@ class ShippingInfoWidget @JvmOverloads constructor(
 
         val isPostalCodeValid = shippingPostalCodeValidator.isValid(
             postalCode,
-            countryAutoCompleteTextView.selectedCountryCode.orEmpty(),
+            countryAutoCompleteTextView.selectedCountry.code,
             optionalShippingInfoFields,
             hiddenShippingInfoFields
         )
@@ -235,20 +231,13 @@ class ShippingInfoWidget @JvmOverloads constructor(
     }
 
     private fun initView() {
-        countryAutoCompleteTextView.setCountryChangeListener(
-            object : CountryAutoCompleteTextView.CountryChangeListener {
-                override fun onCountryChanged(countryCode: String) {
-                    renderCountrySpecificLabels(countryCode)
-                }
-            }
-        )
+        countryAutoCompleteTextView.countryChangeCallback = ::renderCountrySpecificLabels
+
         phoneNumberEditText.addTextChangedListener(PhoneNumberFormattingTextWatcher())
         setupErrorHandling()
         renderLabels()
 
-        countryAutoCompleteTextView.selectedCountryCode?.let { selectedCountryCode ->
-            renderCountrySpecificLabels(selectedCountryCode)
-        }
+        countryAutoCompleteTextView.selectedCountry.let(::renderCountrySpecificLabels)
     }
 
     private fun setupErrorHandling() {
@@ -303,16 +292,16 @@ class ShippingInfoWidget @JvmOverloads constructor(
         }
     }
 
-    private fun renderCountrySpecificLabels(countrySelected: String) {
-        when (countrySelected) {
+    private fun renderCountrySpecificLabels(country: Country) {
+        when (country.code) {
             Locale.US.country -> renderUSForm()
             Locale.UK.country -> renderGreatBritainForm()
             Locale.CANADA.country -> renderCanadianForm()
             else -> renderInternationalForm()
         }
 
         postalCodeTextInputLayout.visibility =
-            if (CountryUtils.doesCountryUsePostalCode(countrySelected) &&
+            if (CountryUtils.doesCountryUsePostalCode(country.code) &&
                 !isFieldHidden(CustomizableShippingField.POSTAL_CODE_FIELD)) {
                 View.VISIBLE
             } else {

stripe/src/test/java/com/stripe/android/view/CountryAdapterTest.kt

@@ -17,9 +17,9 @@ import org.robolectric.RobolectricTestRunner
 class CountryAdapterTest {
 
     private lateinit var countryAdapter: CountryAdapter
-    private lateinit var orderedCountries: List<String>
+    private lateinit var orderedCountries: List<Country>
 
-    private val suggestions: List<String>
+    private val suggestions: List<Country>
         get() {
             return (0 until countryAdapter.count).mapNotNull {
                 countryAdapter.getItem(it)
@@ -66,7 +66,7 @@ class CountryAdapterTest {
                 "United Kingdom",
                 "United States Minor Outlying Islands"
             ),
-            suggestions
+            suggestions.map { it.name }
         )
     }