diff --git a/.gitignore b/.gitignore
new file mode 100755
index 0000000..b846899
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,22 @@
+# Xcode
+.DS_Store
+*/build/*
+*.pbxuser
+!default.pbxuser
+*.mode1v3
+!default.mode1v3
+*.mode2v3
+!default.mode2v3
+*.perspectivev3
+!default.perspectivev3
+xcuserdata
+profile
+*.moved-aside
+DerivedData
+.idea/
+*.hmap
+*.xccheckout
+*.mov
+
+#CocoaPods
+Pods
diff --git a/SJDatePicker.xcodeproj/project.pbxproj b/SJDatePicker.xcodeproj/project.pbxproj
index 63b89e1..6a9fa1d 100644
--- a/SJDatePicker.xcodeproj/project.pbxproj
+++ b/SJDatePicker.xcodeproj/project.pbxproj
@@ -114,7 +114,7 @@
 				TargetAttributes = {
 					71F93C761E9D477A00FF18AA = {
 						CreatedOnToolsVersion = 8.2.1;
-						DevelopmentTeam = U496Y4TUDA;
+						DevelopmentTeam = 8MAB78TT6T;
 						LastSwiftMigration = 0820;
 						ProvisioningStyle = Automatic;
 					};
@@ -282,7 +282,7 @@
 			buildSettings = {
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				CLANG_ENABLE_MODULES = YES;
-				DEVELOPMENT_TEAM = U496Y4TUDA;
+				DEVELOPMENT_TEAM = 8MAB78TT6T;
 				INFOPLIST_FILE = SJDatePicker/Info.plist;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = tw.sabrina.SJDatePicker;
@@ -298,7 +298,7 @@
 			buildSettings = {
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				CLANG_ENABLE_MODULES = YES;
-				DEVELOPMENT_TEAM = U496Y4TUDA;
+				DEVELOPMENT_TEAM = 8MAB78TT6T;
 				INFOPLIST_FILE = SJDatePicker/Info.plist;
 				LD_RUNPATH_SEARCH_PATHS = "$(inherited) @executable_path/Frameworks";
 				PRODUCT_BUNDLE_IDENTIFIER = tw.sabrina.SJDatePicker;
diff --git a/SJDatePicker.xcodeproj/project.xcworkspace/xcuserdata/eileen.xcuserdatad/UserInterfaceState.xcuserstate b/SJDatePicker.xcodeproj/project.xcworkspace/xcuserdata/eileen.xcuserdatad/UserInterfaceState.xcuserstate
index 0cc5714..933a77c 100644
Binary files a/SJDatePicker.xcodeproj/project.xcworkspace/xcuserdata/eileen.xcuserdatad/UserInterfaceState.xcuserstate and b/SJDatePicker.xcodeproj/project.xcworkspace/xcuserdata/eileen.xcuserdatad/UserInterfaceState.xcuserstate differ
diff --git a/SJDatePicker/Assets.xcassets/AppIcon.appiconset/Contents.json b/SJDatePicker/Assets.xcassets/AppIcon.appiconset/Contents.json
index 118c98f..19882d5 100644
--- a/SJDatePicker/Assets.xcassets/AppIcon.appiconset/Contents.json
+++ b/SJDatePicker/Assets.xcassets/AppIcon.appiconset/Contents.json
@@ -1,5 +1,15 @@
 {
   "images" : [
+    {
+      "idiom" : "iphone",
+      "size" : "20x20",
+      "scale" : "2x"
+    },
+    {
+      "idiom" : "iphone",
+      "size" : "20x20",
+      "scale" : "3x"
+    },
     {
       "idiom" : "iphone",
       "size" : "29x29",
@@ -29,6 +39,11 @@
       "idiom" : "iphone",
       "size" : "60x60",
       "scale" : "3x"
+    },
+    {
+      "idiom" : "ios-marketing",
+      "size" : "1024x1024",
+      "scale" : "1x"
     }
   ],
   "info" : {
diff --git a/SJDatePicker/SJDatePicker/PresentedViewController.swift b/SJDatePicker/SJDatePicker/PresentedViewController.swift
index b5af408..026d27d 100644
--- a/SJDatePicker/SJDatePicker/PresentedViewController.swift
+++ b/SJDatePicker/SJDatePicker/PresentedViewController.swift
@@ -28,15 +28,15 @@ class PresentedViewController: UIViewController {
     public var pickerMode:UIDatePickerMode = .dateAndTime
     public var minimumDate:Date? = nil
     public var maximumDate:Date? = nil
-    public var date_format:dateformat = .yyyy_To_ss
+    public var returnDateFormat:dateformat = .yyyy_To_ss
     public var titleString:String? = nil
     
-    private var picker:UIDatePicker = UIDatePicker.init()
-    private var confirmButton:UIButton = UIButton.init()
-    private let cornerRadius:CGFloat = 7.5
-    private let highlightedView:UIView = UIView.init()
-    private let pickerHeight:CGFloat = 216
-    private let pickerWidth:CGFloat = UIScreen.main.bounds.size.width - 10
+    fileprivate var picker:UIDatePicker = UIDatePicker.init()
+    fileprivate var confirmButton:UIButton = UIButton.init()
+    fileprivate let cornerRadius:CGFloat = 7.5
+    fileprivate let highlightedView:UIView = UIView.init()
+    fileprivate let pickerHeight:CGFloat = 216
+    fileprivate let pickerWidth:CGFloat = UIScreen.main.bounds.size.width - 10
     
     var block:returnDate?
     
@@ -61,16 +61,16 @@ class PresentedViewController: UIViewController {
         picker.layer.cornerRadius = cornerRadius
         picker.datePickerMode = self.pickerMode
         
-        if minimumDate != nil {
-            picker.minimumDate = self.minimumDate!
+        if let minDate = minimumDate {
+            picker.minimumDate = minDate
         }
         
-        if maximumDate != nil{
-            picker.maximumDate = self.maximumDate!
+        if let maxDate = maximumDate {
+            picker.maximumDate = maxDate
         }
         
-        if minimumDate != nil && maximumDate != nil {
-            assert(minimumDate! < maximumDate!, "minimum date cannot bigger then maximum date")
+        if let minDate = minimumDate, let maxDate = maximumDate {
+            assert(minDate < maxDate, "minimum date cannot bigger then maximum date")
         }
         
         picker.layer.masksToBounds = true
@@ -118,13 +118,12 @@ class PresentedViewController: UIViewController {
         if block != nil {
             self.dismiss(animated: true, completion: nil)
             let df:DateFormatter = DateFormatter.init()
-            df.dateFormat = date_format.rawValue
+            df.dateFormat = returnDateFormat.rawValue
             df.timeZone = TimeZone(secondsFromGMT: TimeZone.current.secondsFromGMT())
             let returnDate:String = df.string(from: picker.date)
             block!(returnDate)
         }
     }
-    
 }
 
 extension PresentedViewController:UIViewControllerTransitioningDelegate{