FEAT: email validator

app/src/main/java/cz/qase/android/formbuilderproject/MainActivity.kt

@@ -11,6 +11,7 @@ import cz.qase.android.formbuilderlibrary.element.*
 import cz.qase.android.formbuilderlibrary.element.generic.ActionCallback
 import cz.qase.android.formbuilderlibrary.element.generic.CheckboxCallback
 import cz.qase.android.formbuilderlibrary.element.generic.ValueCallback
+import cz.qase.android.formbuilderlibrary.validator.EmailValidator
 import cz.qase.android.formbuilderlibrary.validator.MaxLengthFormValidator
 import cz.qase.android.formbuilderlibrary.validator.NotBlankFormValidator
 import cz.qase.android.formbuilderlibrary.validator.NotInPastValidator
@@ -29,6 +30,7 @@ class MainActivity : AppCompatActivity() {
     private val longerStringValues = (1..5).map { randomString(25) }
 
     private val notEmptyValidator = NotBlankFormValidator("This field is empty")
+    private val emailValidator = EmailValidator("This is not valid email!")
     private val maxLengthValidator = MaxLengthFormValidator("This filed has more than 10 characters.", 10)
 
     private val validateActionCallback = object : ActionCallback, Form.Callback {
@@ -125,7 +127,7 @@ class MainActivity : AppCompatActivity() {
             override fun callback(value: String) {
                 Toast.makeText(applicationContext, value, Toast.LENGTH_SHORT).show()
             }
-        }, arrayListOf(notEmptyValidator)))
+        }, arrayListOf(emailValidator)))
         addSpace()
 
         //action elements

formbuilderlibrary/src/main/java/cz/qase/android/formbuilderlibrary/validator/EmailValidator.kt

@@ -0,0 +1,21 @@
+package cz.qase.android.formbuilderlibrary.validator
+
+import android.util.Patterns
+import cz.qase.android.formbuilderlibrary.ValidationException
+
+/**
+ * Field validator
+ *
+ * Is ok when value is not null and not blank (aka empty or made only of whitespaces)
+ * see String.isNullOrBlank()
+ */
+class EmailValidator(private val errorMsg: String) : FormValidator<String> {
+    override fun validate(value: String?) {
+        if (value.isNullOrBlank()) {
+            throw ValidationException(errorMsg)
+        }
+        if (!Patterns.EMAIL_ADDRESS.matcher(value).matches()) {
+            throw ValidationException(errorMsg)
+        }
+    }
+}