Custom DropDownCell support without NIB

Demo/CheckboxCell.swift

@@ -0,0 +1,42 @@
+//
+//  CheckboxCell.swift
+//  Demo
+//
+//  Created by Aleksei Cherepanov on 31/10/2018.
+//  Copyright © 2018 Kevin Hirsch. All rights reserved.
+//
+
+import UIKit
+import DropDown
+
+class CheckboxCell: DropDownCustomCell {
+
+    override func setSelected(_ selected: Bool, animated: Bool) {
+        let executeSelection: () -> Void = { [weak self] in
+            guard let `self` = self else { return }
+            self.accessoryType = selected ? .checkmark : .none
+        }
+
+        if animated {
+            UIView.animate(withDuration: 0.3, animations: {
+                executeSelection()
+            })
+        } else {
+            executeSelection()
+        }
+        accessibilityTraits = selected ? .selected : .none
+    }
+
+    override func systemLayoutSizeFitting(_ targetSize: CGSize) -> CGSize {
+        let contentSize = optionLabel.systemLayoutSizeFitting(targetSize)
+        let accessoryViewWidth:CGFloat = 40
+        return CGSize(width: contentSize.width + accessoryViewWidth,
+                      height: contentSize.height)
+    }
+
+    override func layoutSubviews() {
+        super.layoutSubviews()
+        optionLabel.frame = contentView.bounds
+    }
+
+}

Demo/MySecondCell.swift

@@ -0,0 +1,39 @@
+//
+//  MySecondCell.swift
+//  Demo
+//
+//  Created by Aleksei Cherepanov on 31/10/2018.
+//  Copyright © 2018 Kevin Hirsch. All rights reserved.
+//
+
+import UIKit
+import DropDown
+
+class MySecondCell: DropDownCustomCell {
+    var logoImageView = UIImageView(frame: .zero)
+
+    required init?(coder aDecoder: NSCoder) {
+        super.init(coder: aDecoder)
+    }
+
+    override init(style: UITableViewCell.CellStyle, reuseIdentifier: String?) {
+        super.init(style: style, reuseIdentifier: reuseIdentifier)
+        contentView.addSubview(logoImageView)
+    }
+
+    override func layoutSubviews() {
+        super.layoutSubviews()
+        let size = contentView.bounds.size
+        let imageSize = logoImageView.image?.size ?? .zero
+        let padding: CGFloat = 4
+        logoImageView.frame = CGRect(x: padding,
+                                     y: (frame.height - imageSize.height)/2,
+                                     width: imageSize.width,
+                                     height: imageSize.height)
+        let offset = padding * 2 + imageSize.width
+        optionLabel.frame = CGRect(x: offset,
+                                   y: 0,
+                                   width: size.width - offset,
+                                   height: size.height)
+    }
+}

Demo/ViewController.swift

@@ -81,6 +81,8 @@ class ViewController: UIViewController {
 		switch sender.selectedSegmentIndex {
 		case 0: setupDefaultDropDown()
 		case 1: customizeDropDown(self)
+        case 2: customizeDropDownWithClass(self)
+        case 3: customizeDropDownSelector(self)
 		default: break;
 		}
 	}
@@ -134,6 +136,31 @@ class ViewController: UIViewController {
 			/*** ---------------- ***/
 		}
 	}
+
+    func customizeDropDownWithClass(_ sender: AnyObject) {
+        dropDowns.forEach {
+            /*** FOR CUSTOM CELLS ***/
+            $0.cellClass = MySecondCell.self
+
+            $0.customCellConfiguration = { (index: Index, item: String, cell: DropDownCell) -> Void in
+                guard let cell = cell as? MySecondCell else { return }
+
+                // Setup your custom UI components
+                cell.logoImageView.image = UIImage(named: "logo_\(index % 10)")
+            }
+            /*** ---------------- ***/
+        }
+    }
+
+    func customizeDropDownSelector(_ sender: AnyObject) {
+        dropDowns.forEach {
+            /*** FOR CUSTOM CELLS ***/
+            $0.cellClass = CheckboxCell.self
+            $0.customCellConfiguration = nil
+        }
+    }
+
+
 
 	//MARK: - UIViewController
 
@@ -143,6 +170,8 @@ class ViewController: UIViewController {
 		setupDropDowns()
 		dropDowns.forEach { $0.dismissMode = .onTap }
 		dropDowns.forEach { $0.direction = .any }
+
+        dropDowns.forEach { $0.showArrowIndicator = true }
 
 		view.addSubview(textField)
 	}

DropDown.xcodeproj/project.pbxproj

@@ -25,6 +25,8 @@
 		0AB5D89A1D0EF15D002D3A17 /* ViewController.swift in Sources */ = {isa = PBXBuildFile; fileRef = 0AB5D8971D0EF15D002D3A17 /* ViewController.swift */; };
 		0AB5D8A11D0EF173002D3A17 /* Main.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 0AB5D89F1D0EF173002D3A17 /* Main.storyboard */; };
 		0AC1C33A1B6B884100A8DC0D /* Images.xcassets in Resources */ = {isa = PBXBuildFile; fileRef = 0AC1C3391B6B884100A8DC0D /* Images.xcassets */; };
+		9442B7DB2189B8EC000720B8 /* CheckboxCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9442B7DA2189B8EC000720B8 /* CheckboxCell.swift */; };
+		945A86E22188BD39007B8D96 /* MySecondCell.swift in Sources */ = {isa = PBXBuildFile; fileRef = 945A86E12188BD39007B8D96 /* MySecondCell.swift */; };
 /* End PBXBuildFile section */
 
 /* Begin PBXContainerItemProxy section */
@@ -81,6 +83,8 @@
 		0AB5D8971D0EF15D002D3A17 /* ViewController.swift */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.swift; path = ViewController.swift; sourceTree = "<group>"; };
 		0AB5D8A01D0EF173002D3A17 /* Base */ = {isa = PBXFileReference; lastKnownFileType = file.storyboard; name = Base; path = Base.lproj/Main.storyboard; sourceTree = "<group>"; };
 		0AC1C3391B6B884100A8DC0D /* Images.xcassets */ = {isa = PBXFileReference; lastKnownFileType = folder.assetcatalog; name = Images.xcassets; path = Demo/Images.xcassets; sourceTree = "<group>"; };
+		9442B7DA2189B8EC000720B8 /* CheckboxCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CheckboxCell.swift; sourceTree = "<group>"; };
+		945A86E12188BD39007B8D96 /* MySecondCell.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MySecondCell.swift; sourceTree = "<group>"; };
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
@@ -137,6 +141,8 @@
 				0AB5D8971D0EF15D002D3A17 /* ViewController.swift */,
 				0A8518D41D6480190089529A /* MyCell.swift */,
 				0A8518D61D6481E30089529A /* MyCell.xib */,
+				945A86E12188BD39007B8D96 /* MySecondCell.swift */,
+				9442B7DA2189B8EC000720B8 /* CheckboxCell.swift */,
 				0AB5D89F1D0EF173002D3A17 /* Main.storyboard */,
 				0AB5D8961D0EF15D002D3A17 /* NiceButton.swift */,
 				0A7644121B676C2300BF1A2D /* Supporting Files */,
@@ -358,8 +364,10 @@
 			files = (
 				0AB5D89A1D0EF15D002D3A17 /* ViewController.swift in Sources */,
 				0A8518D51D6480190089529A /* MyCell.swift in Sources */,
+				9442B7DB2189B8EC000720B8 /* CheckboxCell.swift in Sources */,
 				0AB5D8991D0EF15D002D3A17 /* NiceButton.swift in Sources */,
 				0AB5D8981D0EF15D002D3A17 /* AppDelegate.swift in Sources */,
+				945A86E22188BD39007B8D96 /* MySecondCell.swift in Sources */,
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 		};

DropDown/helpers/DPDConstants.swift

@@ -30,6 +30,7 @@ internal struct DPDConstant {
 		static let BackgroundColor = UIColor(white: 0.94, alpha: 1)
 		static let SelectionBackgroundColor = UIColor(white: 0.89, alpha: 1)
 		static let SeparatorColor = UIColor.clear
+        static let SeparatorInset = UIEdgeInsets.zero
 		static let CornerRadius: CGFloat = 2
 		static let RowHeight: CGFloat = 44
 		static let HeightPadding: CGFloat = 20

DropDown/src/DropDown.swift

@@ -159,15 +159,21 @@ public final class DropDown: UIView {
 	*/
 	public var arrowIndicationX: CGFloat? {
 		didSet {
-			if let arrowIndicationX = arrowIndicationX {
-				tableViewContainer.addSubview(arrowIndication)
-				arrowIndication.tintColor = tableViewBackgroundColor
-				arrowIndication.frame.origin.x = arrowIndicationX
-			} else {
-				arrowIndication.removeFromSuperview()
-			}
+			guard let x = arrowIndicationX else { return }
+            arrowIndication.frame.origin.x = x
+            showArrowIndicator = true
 		}
 	}
+    public var showArrowIndicator: Bool = false {
+        didSet {
+            if showArrowIndicator {
+                tableViewContainer.addSubview(arrowIndication)
+                arrowIndication.tintColor = tableViewBackgroundColor
+            } else {
+                arrowIndication.removeFromSuperview()
+            }
+        }
+    }
 
 	//MARK: Constraints
 	fileprivate var heightConstraint: NSLayoutConstraint!
@@ -184,7 +190,7 @@ public final class DropDown: UIView {
 	@objc fileprivate dynamic var tableViewBackgroundColor = DPDConstant.UI.BackgroundColor {
 		willSet {
             tableView.backgroundColor = newValue
-            if arrowIndicationX != nil { arrowIndication.tintColor = newValue }
+            if showArrowIndicator { arrowIndication.tintColor = newValue }
         }
 	}
 
@@ -216,6 +222,16 @@ public final class DropDown: UIView {
 		willSet { tableView.separatorColor = newValue }
 		didSet { reloadAllComponents() }
 	}
+
+    /**
+     The separator inset
+
+     Changing the separator inset automatically reloads the drop down.
+     */
+    @objc public dynamic var separatorInset = DPDConstant.UI.SeparatorInset {
+        willSet { tableView.separatorInset = newValue }
+        didSet { reloadAllComponents() }
+    }
 
 	/**
 	The corner radius of DropDown.
@@ -362,6 +378,14 @@ public final class DropDown: UIView {
 			reloadAllComponents()
 		}
 	}
+
+    public var cellClass: DropDownCustomCell.Type = DropDownCustomCell.self {
+        didSet {
+            tableView.register(cellClass, forCellReuseIdentifier: DPDConstant.ReusableIdentifier.DropDownCell)
+            templateCell = nil
+            reloadAllComponents()
+        }
+    }
 
 	//MARK: Content
 
@@ -538,6 +562,7 @@ private extension DropDown {
 
 		tableView.backgroundColor = tableViewBackgroundColor
 		tableView.separatorColor = separatorColor
+        tableView.separatorInset = separatorInset
 		tableView.layer.cornerRadius = cornerRadius
 		tableView.layer.masksToBounds = true
 	}
@@ -693,20 +718,25 @@ extension DropDown {
 				direction = .top
 			}
 		}
-		
+        
 		constraintWidthToFittingSizeIfNecessary(layout: &layout)
 		constraintWidthToBoundsIfNecessary(layout: &layout, in: window)
 
 		let visibleHeight = tableHeight - layout.offscreenHeight
 		let canBeDisplayed = visibleHeight >= minHeight
 
+        if showArrowIndicator {
+            arrowIndication.frame.origin.x = computeArrowIndicator(window: window,
+                                                                   layout: layout)
+        }
+
 		return (layout.x, layout.y, layout.width, layout.offscreenHeight, visibleHeight, canBeDisplayed, direction)
 	}
 
 	fileprivate func computeLayoutBottomDisplay(window: UIWindow) -> ComputeLayoutTuple {
 		var offscreenHeight: CGFloat = 0
 
-		let width = self.width ?? (anchorView?.plainView.bounds.width ?? fittingWidth()) - bottomOffset.x
+		let width = self.width ?? fittingWidth() - bottomOffset.x
 
 		let anchorViewX = anchorView?.plainView.windowFrame?.minX ?? window.frame.midX - (width / 2)
 		let anchorViewY = anchorView?.plainView.windowFrame?.minY ?? window.frame.midY - (tableHeight / 2)
@@ -749,16 +779,27 @@ extension DropDown {
 
 		return (x, y, width, offscreenHeight)
 	}
+
+    fileprivate func computeArrowIndicator(window: UIWindow, layout: ComputeLayoutTuple) -> CGFloat {
+        if let x = arrowIndicationX { return x }
+        guard let anchorViewX = anchorView?.plainView.windowFrame?.minX else {
+            return layout.width / 2
+        }
+        let anchorViewWidth = anchorView?.plainView.bounds.width ?? 0
+        let leftSpacing = max(anchorViewX - layout.x, 0)
+        return leftSpacing + anchorViewWidth/2
+    }
 
 	fileprivate func fittingWidth() -> CGFloat {
 		if templateCell == nil {
-			templateCell = (cellNib.instantiate(withOwner: nil, options: nil)[0] as! DropDownCell)
+            templateCell = (tableView.dequeueReusableCell(withIdentifier: DPDConstant.ReusableIdentifier.DropDownCell) as! DropDownCell)
 		}
 
 		var maxWidth: CGFloat = 0
 
 		for index in 0..<dataSource.count {
 			configureCell(templateCell, at: index)
+            templateCell.setSelected(true, animated: false)
 			templateCell.bounds.size.height = cellHeight
 			let width = templateCell.systemLayoutSizeFitting(UIView.layoutFittingCompressedSize).width
 

DropDown/src/DropDownCell.swift

@@ -19,6 +19,20 @@ open class DropDownCell: UITableViewCell {
 
 }
 
+open class DropDownCustomCell: DropDownCell {
+    var strongOptionLabel = UILabel(frame: .zero)
+
+    required public init?(coder aDecoder: NSCoder) {
+        super.init(coder: aDecoder)
+    }
+
+    override public init(style: UITableViewCell.CellStyle, reuseIdentifier: String?) {
+        super.init(style: style, reuseIdentifier: reuseIdentifier)
+        optionLabel = strongOptionLabel
+        contentView.addSubview(strongOptionLabel)
+    }
+}
+
 //MARK: - UI
 
 extension DropDownCell {

README.md

@@ -196,6 +196,12 @@ dropDown.customCellConfiguration = { (index: Index, item: String, cell: DropDown
 
 For a complete example, don't hesitate to check the demo app and code.
 
+To avoid NIBs use 
+```swift
+dropDown.cellClass = CellClassName.self
+```
+Where `CellClassName` is subclass of `DropDownCustomCell`.
+
 ### Events
 
 ```swift