From dd7007d6ade90fa9ce3ee21e94462730c7e04c65 Mon Sep 17 00:00:00 2001
From: Caio Mathielo <mathielo@gmail.com>
Date: Wed, 28 Oct 2015 18:22:24 -0200
Subject: [PATCH 1/3] Adding public method validateField()

---
 SwiftValidator/Core/Validator.swift | 20 ++++++++++++++++++++
 Validator/ViewController.swift      | 14 ++++++++++++++
 2 files changed, 34 insertions(+)

diff --git a/SwiftValidator/Core/Validator.swift b/SwiftValidator/Core/Validator.swift
index f9b806c..a5d41df 100644
--- a/SwiftValidator/Core/Validator.swift
+++ b/SwiftValidator/Core/Validator.swift
@@ -47,6 +47,26 @@ public class Validator {
         }
     }
     
+    // MARK: Public functions
+    
+    public func validateField(textField: UITextField, callback: (error:ValidationError?) -> Void){
+        if let fieldRule = validations[textField] {
+            if let error = fieldRule.validateField() {
+                if let transform = self.errorStyleTransform {
+                    transform(validationError: error)
+                }
+                callback(error: error)
+            } else {
+                if let transform = self.successStyleTransform {
+                    transform(validationRule: fieldRule)
+                }
+                callback(error: nil)
+            }
+        } else {
+            callback(error: nil)
+        }
+    }
+    
     // MARK: Using Keys
     
     public func styleTransformers(success success:((validationRule:ValidationRule)->Void)?, error:((validationError:ValidationError)->Void)?) {
diff --git a/Validator/ViewController.swift b/Validator/ViewController.swift
index 6d37f64..f273e1a 100644
--- a/Validator/ViewController.swift
+++ b/Validator/ViewController.swift
@@ -78,4 +78,18 @@ class ViewController: UIViewController , ValidationDelegate, UITextFieldDelegate
     func hideKeyboard(){
         self.view.endEditing(true)
     }
+    
+    // MARK: Validate single field
+    // Don't forget to use UITextFieldDelegate
+    func textFieldShouldReturn(textField: UITextField) -> Bool {
+            validator.validateField(textField){ error in
+                if error == nil {
+                    // Field validation was successful
+                } else {
+                    // Validation error occurred
+                }
+            }
+        return true
+    }
+
 }
\ No newline at end of file

From 73e1e443a5dd8ef06c89a2667e9a0bf017f545af Mon Sep 17 00:00:00 2001
From: Caio Mathielo <mathielo@gmail.com>
Date: Wed, 28 Oct 2015 18:30:00 -0200
Subject: [PATCH 2/3] Updating README, adding Single Field Validation

---
 README.md | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/README.md b/README.md
index aaf230d..ac4c224 100644
--- a/README.md
+++ b/README.md
@@ -108,6 +108,26 @@ func validationFailed(errors:[UITextField:ValidationError]) {
 
 ```
 
+### Single Field Validation
+
+You may use single field validation in some cases. This could be useful in situations such as controlling responders:
+
+```swift
+// Don't forget to use UITextFieldDelegate
+// and delegate yourTextField to self in viewDidLoad()
+func textFieldShouldReturn(textField: UITextField) -> Bool {
+    validator.validateField(textField){ error in
+        if error == nil {
+            // Field validation was successful
+        } else {
+            // Validation error occurred
+        }
+    }
+    return true
+}
+```
+
+
 ## Custom Validation 
 
 We will create a ```SSNRule``` class to show how to create your own Validation. A United States Social Security Number (or SSN) is a field that consists of XXX-XX-XXXX. 

From fdf332d024f9e81ba6f04bce5135bb15a11959cb Mon Sep 17 00:00:00 2001
From: Caio Mathielo <mathielo@gmail.com>
Date: Wed, 6 Jan 2016 12:43:29 -0200
Subject: [PATCH 3/3] Adding single field validation Tests

---
 SwiftValidatorTests/SwiftValidatorTests.swift | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/SwiftValidatorTests/SwiftValidatorTests.swift b/SwiftValidatorTests/SwiftValidatorTests.swift
index 0c34d25..0a3c1a0 100644
--- a/SwiftValidatorTests/SwiftValidatorTests.swift
+++ b/SwiftValidatorTests/SwiftValidatorTests.swift
@@ -211,6 +211,18 @@ class SwiftValidatorTests: XCTestCase {
         }
     }
     
+    func testValidateSingleField() {
+        REGISTER_VALIDATOR.registerField(REGISTER_TXT_FIELD, rules: [EmailRule()])
+        REGISTER_TXT_FIELD.text = VALID_EMAIL
+        REGISTER_VALIDATOR.validateField(REGISTER_TXT_FIELD) { error in
+            XCTAssert(error == nil, "Should not present error")
+        }
+        REGISTER_TXT_FIELD.text = INVALID_EMAIL
+        REGISTER_VALIDATOR.validateField(REGISTER_TXT_FIELD) { error in
+            XCTAssert(error?.errorMessage.characters.count > 0, "Should state 'invalid email'")
+        }
+    }
+    
     // MARK: Validate error field gets it's text set to the error, if supplied
     
     func testNoErrorMessageSet() {