Implemented showing validation errors on UI

BankingUiCommon/build.gradle

@@ -20,4 +20,8 @@ dependencies {
 
     // TODO: try to get rid of this import
     api project(':fints4javaLib')
+
+
+    testImplementation "junit:junit:$junitVersion"
+    testImplementation "org.assertj:assertj-core:$assertJVersion"
 }

BankingUiCommon/src/main/java/net/dankito/banking/util/InputValidator.kt

@@ -0,0 +1,86 @@
+package net.dankito.banking.util
+
+import net.dankito.fints.messages.segmente.implementierte.sepa.ISepaMessageCreator
+import net.dankito.fints.messages.segmente.implementierte.sepa.SepaMessageCreator
+import java.util.regex.Pattern
+
+
+open class InputValidator {
+
+    companion object {
+
+        /**
+         * The IBAN consists of up to 34 alphanumeric characters, as follows:
+         * - country code using ISO 3166-1 alpha-2 – two letters,
+         * - check digits – two digits, and
+         * - Basic Bank Account Number (BBAN) – up to 30 alphanumeric characters that are country-specific.
+         * (https://en.wikipedia.org/wiki/International_Bank_Account_Number#Structure)
+         */
+        const val IbanPatternString = "[A-Z]{2}\\d{2}[A-Z0-9]{10,30}"
+        val IbanPattern = Pattern.compile("^" + IbanPatternString + "\$")
+
+        /**
+         * The IBAN should not contain spaces when transmitted electronically. When printed it is expressed in groups
+         * of four characters separated by a single space, the last group being of variable length as shown in the example below
+         * (https://en.wikipedia.org/wiki/International_Bank_Account_Number#Structure)
+         */
+        const val IbanWithSpacesPatternString = "[A-Z]{2}\\d{2}\\s([A-Z0-9]{4}\\s){3}[A-Z0-9\\s]{1,18}"
+        val IbanWithSpacesPattern = Pattern.compile("^" + IbanWithSpacesPatternString + "\$")
+
+        val InvalidIbanCharactersPattern = Pattern.compile("[^A-Z0-9 ]")
+
+
+        /**
+         * The SWIFT code is 8 or 11 characters, made up of:
+         * - 4 letters: institution code or bank code.
+         * - 2 letters: ISO 3166-1 alpha-2 country code (exceptionally, SWIFT has assigned the code XK to Republic of Kosovo, which does not have an ISO 3166-1 country code)
+         * - 2 letters or digits: location code
+         * -- if the second character is "0", then it is typically a test BIC as opposed to a BIC used on the live network.
+         * -- if the second character is "1", then it denotes a passive participant in the SWIFT network
+         * -- if the second character is "2", then it typically indicates a reverse billing BIC, where the recipient pays for the message as opposed to the more usual mode whereby the sender pays for the message.
+         * - 3 letters or digits: branch code, optional ('XXX' for primary office)
+         * Where an eight digit code is given, it may be assumed that it refers to the primary office.
+         */
+        const val BicPatternString = "[A-Z]{4}[A-Z]{2}[A-Z0-9]{2}(?:\\b|[A-Z0-9]{03})"
+        val BicPattern = Pattern.compile("^" + BicPatternString + "$")
+
+
+        val InvalidSepaCharactersPattern = Pattern.compile("[^${SepaMessageCreator.AllowedSepaCharacters}]+")
+    }
+
+
+    protected val sepaMessageCreator: ISepaMessageCreator = SepaMessageCreator()
+
+
+    open fun isValidIban(stringToTest: String): Boolean {
+        return IbanPattern.matcher(stringToTest).matches() ||
+                IbanWithSpacesPattern.matcher(stringToTest).matches()
+    }
+
+    open fun getInvalidIbanCharacters(string: String): String {
+        return getInvalidCharacters(string, InvalidIbanCharactersPattern)
+    }
+
+
+    open fun containsOnlyValidSepaCharacters(stringToTest: String): Boolean {
+        return sepaMessageCreator.containsOnlyAllowedCharacters(stringToTest)
+    }
+
+    open fun getInvalidSepaCharacters(string: String): String {
+        return getInvalidCharacters(string, InvalidSepaCharactersPattern)
+    }
+
+
+    open fun getInvalidCharacters(string: String, pattern: Pattern): String {
+        val illegalCharacters = mutableSetOf<String>()
+
+        val matcher = pattern.matcher(string)
+
+        while (matcher.find()) {
+            illegalCharacters.add(matcher.group())
+        }
+
+        return illegalCharacters.joinToString("")
+    }
+
+}

BankingUiCommon/src/test/kotlin/net/dankito/banking/util/InputValidatorTest.kt

@@ -0,0 +1,38 @@
+package net.dankito.banking.util
+
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.Test
+
+
+class InputValidatorTest {
+
+    private val underTest = InputValidator()
+
+
+    @Test
+    fun getInvalidIbanCharacters() {
+
+        // given
+        val invalidIbanCharacters = "ajvz!@#$%^&*()-_=+[]{}'\"\\|/?.,;:<>"
+
+        // when
+        val result = underTest.getInvalidIbanCharacters("EN${invalidIbanCharacters}1234")
+
+        // then
+        assertThat(result).isEqualTo(invalidIbanCharacters as Any)
+    }
+
+    @Test
+    fun getInvalidSepaCharacters() {
+
+        // given
+        val invalidSepaCharacters = "!€@#$%^&*_=[]{}\\|;<>"
+
+        // when
+        val result = underTest.getInvalidSepaCharacters("abcd${invalidSepaCharacters}1234")
+
+        // then
+        assertThat(result).isEqualTo(invalidSepaCharacters as Any)
+    }
+
+}

fints4javaAndroidApp/src/main/java/net/dankito/banking/fints4java/android/ui/dialogs/TransferMoneyDialog.kt

@@ -18,8 +18,7 @@ import net.dankito.banking.ui.model.BankAccount
 import net.dankito.banking.ui.model.parameters.TransferMoneyData
 import net.dankito.banking.ui.model.responses.BankingClientResponse
 import net.dankito.banking.ui.presenter.BankingPresenter
-import net.dankito.fints.messages.segmente.implementierte.sepa.ISepaMessageCreator
+import net.dankito.banking.util.InputValidator
-import net.dankito.fints.messages.segmente.implementierte.sepa.SepaMessageCreator
 import net.dankito.fints.model.BankInfo
 import net.dankito.utils.android.extensions.asActivity
 import java.math.BigDecimal
@@ -40,7 +39,10 @@ open class TransferMoneyDialog : DialogFragment() {
 
     protected var preselectedValues: TransferMoneyData? = null
 
-    protected val sepaMessageCreator: ISepaMessageCreator = SepaMessageCreator()
+    protected val inputValidator = InputValidator() // TODO: move to presenter
+
+
+    protected var foundBankForEnteredIban = false
 
 
     open fun show(activity: AppCompatActivity, presenter: BankingPresenter, preselectedBankAccount: BankAccount?, fullscreen: Boolean = false) {
@@ -93,6 +95,11 @@ open class TransferMoneyDialog : DialogFragment() {
         rootView.edtxtAmount.addTextChangedListener(otherEditTextChangedWatcher)
         rootView.edtxtUsage.addTextChangedListener(otherEditTextChangedWatcher)
 
+        rootView.edtxtRemitteeName.setOnFocusChangeListener { _, hasFocus -> if (hasFocus == false) checkIfEnteredRemitteeNameIsValid() }
+        rootView.edtxtRemitteeIban.setOnFocusChangeListener { _, hasFocus -> if (hasFocus == false) checkIfEnteredRemitteeIbanIsValid() }
+        rootView.edtxtAmount.setOnFocusChangeListener { _, hasFocus -> if (hasFocus == false) checkIfEnteredAmountIsValid() }
+        rootView.edtxtUsage.setOnFocusChangeListener { _, hasFocus -> if (hasFocus == false) checkIfEnteredUsageTextIsValid() }
+
         rootView.btnCancel.setOnClickListener { dismiss() }
 
         rootView.btnTransferMoney.setOnClickListener { transferMoney() }
@@ -209,23 +216,80 @@ open class TransferMoneyDialog : DialogFragment() {
     }
 
     private fun showValuesForFoundBankOnUiThread(foundBank: BankInfo?) {
+        foundBankForEnteredIban = foundBank != null
+
         edtxtRemitteeBank.setText(if (foundBank != null) (foundBank.name + " " + foundBank.city) else "")
 
         edtxtRemitteeBic.setText(foundBank?.bic ?: "")
 
+        if (foundBankForEnteredIban) {
+            lytRemitteeBic.error = null
+        }
+
         checkIfRequiredDataEnteredOnUiThread()
     }
 
     protected open fun checkIfRequiredDataEnteredOnUiThread() {
-        val requiredDataEntered =
+        val isRemitteeNameValid = isRemitteeNameValid()
-                edtxtRemitteeName.text.toString().isNotEmpty()
+        val isValidIban = isRemitteeIbanValid()
-                && sepaMessageCreator.containsOnlyAllowedCharacters(edtxtRemitteeName.text.toString()) // TODO: show error message for illegal characters
+        val isAmountValid = isAmountGreaterZero()
-                && edtxtRemitteeIban.text.toString().isNotEmpty() // TODO: check if it is of length > 12, in Germany > 22?
+        val isUsageTextValid = isUsageTextValid()
-                && edtxtRemitteeBic?.text.toString().isNotEmpty() // TODO: check if it is of length is 8 or 11?
-                && isAmountGreaterZero()
-                && sepaMessageCreator.containsOnlyAllowedCharacters(edtxtUsage.text.toString()) // TODO: show error message for illegal characters
 
-        btnTransferMoney.isEnabled = requiredDataEntered
+        btnTransferMoney.isEnabled = isRemitteeNameValid && isValidIban
+                && edtxtRemitteeBic?.text.toString().isNotEmpty() // TODO: check if it is of length is 8 or 11?
+                && isAmountValid && isUsageTextValid
+    }
+
+    protected open fun checkIfEnteredRemitteeNameIsValid() {
+        if (isRemitteeNameValid()) {
+            lytRemitteeName.error = null
+        }
+        else {
+            lytRemitteeName.error = context?.getString(R.string.error_invalid_sepa_characters_entered,
+                inputValidator.getInvalidSepaCharacters(edtxtRemitteeName.text.toString()))
+        }
+    }
+
+    protected open fun isRemitteeNameValid(): Boolean {
+        val enteredRemitteeName = edtxtRemitteeName.text.toString()
+
+        return enteredRemitteeName.isNotEmpty()
+                && inputValidator.containsOnlyValidSepaCharacters(enteredRemitteeName)
+    }
+
+    protected open fun checkIfEnteredRemitteeIbanIsValid() {
+        if (isRemitteeIbanValid()) {
+            lytRemitteeIban.error = null
+        }
+        else {
+            val invalidIbanCharacters = inputValidator.getInvalidIbanCharacters(edtxtRemitteeIban.text.toString())
+            if (invalidIbanCharacters.isNotEmpty()) {
+                lytRemitteeIban.error = context?.getString(R.string.error_invalid_iban_characters_entered, invalidIbanCharacters)
+            }
+            else {
+                lytRemitteeIban.error = context?.getString(R.string.error_invalid_iban_pattern_entered)
+            }
+        }
+
+        if (foundBankForEnteredIban) {
+            lytRemitteeBic.error = null
+        }
+        else {
+            lytRemitteeBic.error = context?.getString(R.string.error_no_bank_found_for_entered_iban)
+        }
+    }
+
+    protected open fun isRemitteeIbanValid(): Boolean {
+        return inputValidator.isValidIban(edtxtRemitteeIban.text.toString())
+    }
+
+    protected open fun checkIfEnteredAmountIsValid() {
+        if (isAmountGreaterZero()) {
+            lytAmount.error = null
+        }
+        else {
+            lytAmount.error = context?.getString(R.string.error_invalid_amount_entered)
+        }
     }
 
     protected open fun isAmountGreaterZero(): Boolean {
@@ -248,4 +312,18 @@ open class TransferMoneyDialog : DialogFragment() {
         return null
     }
 
+    protected open fun checkIfEnteredUsageTextIsValid() {
+        if (isUsageTextValid()) {
+            lytUsage.error = null
+        }
+        else {
+            lytUsage.error = context?.getString(R.string.error_invalid_sepa_characters_entered,
+                inputValidator.getInvalidSepaCharacters(edtxtUsage.text.toString()))
+        }
+    }
+
+    protected open fun isUsageTextValid(): Boolean {
+        return inputValidator.containsOnlyValidSepaCharacters(edtxtUsage.text.toString())
+    }
+
 }

fints4javaAndroidApp/src/main/res/layout/dialog_transfer_money.xml

@@ -1,5 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
-<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
+<ScrollView
+    xmlns:android="http://schemas.android.com/apk/res/android"
+    xmlns:app="http://schemas.android.com/apk/res-auto"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:padding="@dimen/dialog_transfer_money_padding"
@@ -42,9 +44,11 @@
         </LinearLayout>
 
         <com.google.android.material.textfield.TextInputLayout
+            android:id="@+id/lytRemitteeName"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:hint="@string/dialog_transfer_money_remittee_name"
+            app:errorEnabled="true"
         >
 
             <com.google.android.material.textfield.TextInputEditText
@@ -61,9 +65,11 @@
 
 
         <com.google.android.material.textfield.TextInputLayout
+            android:id="@+id/lytRemitteeIban"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:hint="@string/dialog_transfer_money_remittee_iban"
+            app:errorEnabled="true"
         >
 
             <com.google.android.material.textfield.TextInputEditText
@@ -77,9 +83,11 @@
 
 
         <com.google.android.material.textfield.TextInputLayout
+            android:id="@+id/lytRemitteeBank"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:hint="@string/dialog_transfer_money_remittee_bank"
+            app:errorEnabled="true"
         >
 
             <com.google.android.material.textfield.TextInputEditText
@@ -94,9 +102,11 @@
 
 
         <com.google.android.material.textfield.TextInputLayout
+            android:id="@+id/lytRemitteeBic"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:hint="@string/dialog_transfer_money_remittee_bic"
+            app:errorEnabled="true"
         >
 
             <com.google.android.material.textfield.TextInputEditText
@@ -111,9 +121,11 @@
 
 
         <com.google.android.material.textfield.TextInputLayout
+            android:id="@+id/lytAmount"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:hint="@string/dialog_transfer_money_amount"
+            app:errorEnabled="true"
         >
 
             <com.google.android.material.textfield.TextInputEditText
@@ -127,9 +139,11 @@
 
 
         <com.google.android.material.textfield.TextInputLayout
+            android:id="@+id/lytUsage"
             android:layout_width="match_parent"
             android:layout_height="wrap_content"
             android:hint="@string/dialog_transfer_money_usage"
+            app:errorEnabled="true"
         >
 
             <com.google.android.material.textfield.TextInputEditText

fints4javaAndroidApp/src/main/res/values-de/strings.xml

@@ -51,7 +51,7 @@
     <string name="dialog_transfer_money_remittee_name">Name:</string>
     <string name="dialog_transfer_money_remittee_iban">IBAN:</string>
     <string name="dialog_transfer_money_remittee_bank">Bank (wird automatisch eingetragen):</string>
-    <string name="dialog_transfer_money_remittee_bic">BIC:</string>
+    <string name="dialog_transfer_money_remittee_bic">BIC (wird automatisch eingetragen):</string>
     <string name="dialog_transfer_money_amount">Betrag:</string>
     <string name="dialog_transfer_money_usage">Verwendungszweck:</string>
     <string name="dialog_transfer_money_transfer">Überweisen</string>
@@ -88,4 +88,11 @@
     <string name="dialog_edit_account_ask_should_account_be_deleted">Möchten Sie das Konto \'%s\' wirklich löschen?
         \n\nDies kann nicht rückgängig gemacht werden und die hierzu gespeicherten Daten gehen unwiederbringlich verloren.</string>
 
+
+    <string name="error_invalid_sepa_characters_entered">Unzulässige(s) Zeichen eingegeben: %s</string>
+    <string name="error_invalid_iban_characters_entered">Unzulässige(s) Zeichen eingegeben: %s</string>
+    <string name="error_invalid_iban_pattern_entered">IBANs bestehen aus folgendem Muster: DE12 1234 5678 9012 3456 78</string>
+    <string name="error_no_bank_found_for_entered_iban">Es wurde keine Bank zur eingegebenen IBAN gefunden.</string>
+    <string name="error_invalid_amount_entered">Bitte geben Sie einen Betrag größer 0 ein.</string>
+
 </resources>

fints4javaAndroidApp/src/main/res/values/strings.xml

@@ -51,7 +51,7 @@
     <string name="dialog_transfer_money_remittee_name">Name:</string>
     <string name="dialog_transfer_money_remittee_iban">IBAN:</string>
     <string name="dialog_transfer_money_remittee_bank">Bank (will be entered automatically):</string>
-    <string name="dialog_transfer_money_remittee_bic">BIC:</string>
+    <string name="dialog_transfer_money_remittee_bic">BIC (will be entered automatically):</string>
     <string name="dialog_transfer_money_amount">Amount:</string>
     <string name="dialog_transfer_money_usage">Usage:</string>
     <string name="dialog_transfer_money_transfer">Transfer</string>
@@ -88,4 +88,11 @@
     <string name="dialog_edit_account_ask_should_account_be_deleted">Really delete account \'%s\'?
         \n\nThis cannot be undone and data will be lost.</string>
 
+
+    <string name="error_invalid_sepa_characters_entered">Invalid character(s) entered: %s</string>
+    <string name="error_invalid_iban_characters_entered">Invalid character(s) entered: %s</string>
+    <string name="error_invalid_iban_pattern_entered">IBAN has to have pattern: EN12 1234 5678 9012 3456 78</string>
+    <string name="error_no_bank_found_for_entered_iban">No bank found for entered IBAN.</string>
+    <string name="error_invalid_amount_entered">Please enter an amount greater zero.</string>
+
 </resources>