Merge pull request #15 from dreipol/feature/image_tint

Image manipulation & constraint improvements
dreipol · Mar 10, 2021 · cf0ec8e · cf0ec8e
2 parents 0ebca4e + c83eb88
commit cf0ec8e
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Showing 3 changed files with 112 additions and 23 deletions.
diff --git a/Sources/dreiKit/UIImage+Manipulation.swift b/Sources/dreiKit/UIImage+Manipulation.swift
@@ -0,0 +1,64 @@
+//
+//  UIImage+Manipulation.swift
+//  dreiKit
+//
+//  Created by Samuel Bichsel on 05.03.21.
+//
+
+import UIKit.UIImage
+
+public extension UIImage {
+    func withTintByMultiply(with color: UIColor) -> UIImage {
+        UIGraphicsBeginImageContextWithOptions(size, false, UIScreen.main.scale); defer { UIGraphicsEndImageContext() }
+        guard let context = UIGraphicsGetCurrentContext(), let cgImage = cgImage else {
+            return self
+        }
+
+        // flip the image
+        context.scaleBy(x: 1.0, y: -1.0)
+        context.translateBy(x: 0.0, y: -size.height)
+
+        // multiply blend mode
+        context.setBlendMode(.multiply)
+
+        let rect = CGRect(x: 0, y: 0, width: size.width, height: size.height)
+        context.clip(to: rect, mask: cgImage)
+        color.setFill()
+        context.fill(rect)
+
+        // create UIImage
+        guard let newImage = UIGraphicsGetImageFromCurrentImageContext() else {
+            return self
+        }
+
+        return newImage
+    }
+
+    //   https://stackoverflow.com/questions/20021478/add-transparent-space-around-a-uiimage
+    func withPadding(_ padding: CGFloat) -> UIImage? {
+        return withPadding(x: padding, y: padding)
+    }
+
+    func withPadding(x: CGFloat, y: CGFloat) -> UIImage? {
+        let newWidth = size.width + 2 * x
+        let newHeight = size.height + 2 * y
+        let newSize = CGSize(width: newWidth, height: newHeight)
+        UIGraphicsBeginImageContextWithOptions(newSize, false, 0); defer { UIGraphicsEndImageContext() }
+        let origin = CGPoint(x: (newWidth - size.width) / 2, y: (newHeight - size.height) / 2)
+        draw(at: origin)
+        return UIGraphicsGetImageFromCurrentImageContext()
+    }
+
+    func doubleHeight() -> UIImage {
+        let newHeight = size.height * 2
+        let newSize = CGSize(width: size.width, height: newHeight)
+        UIGraphicsBeginImageContextWithOptions(newSize, false, 0); defer { UIGraphicsEndImageContext() }
+        let origin = CGPoint(x: 0, y: 0)
+        draw(at: origin)
+        guard let newImage = UIGraphicsGetImageFromCurrentImageContext() else {
+            return self
+        }
+
+        return newImage
+    }
+}
diff --git a/Sources/dreiKit/UIView+AutoLayout.swift b/Sources/dreiKit/UIView+AutoLayout.swift
@@ -8,12 +8,23 @@
 
 import UIKit
 
-public extension UIView {
+public struct FillConstraints {
+    public var leading: NSLayoutConstraint
+    public var trailing: NSLayoutConstraint
+    public var top: NSLayoutConstraint
+    public var bottom: NSLayoutConstraint
+
+    public var all: [NSLayoutConstraint] { [leading, trailing, top, bottom] }
+}
 
+public extension UIView {
     class func autoLayout() -> Self {
-        let view = self.init(frame: .zero)
-        view.translatesAutoresizingMaskIntoConstraints = false
-        return view
+        return self.init(frame: .zero).autolayout()
+    }
+
+    func autolayout() -> Self {
+        translatesAutoresizingMaskIntoConstraints = false
+        return self
     }
 
     func activateConstraints(
@@ -34,7 +45,7 @@ public extension UIView {
             widthAnchor.constraint(equalTo: view.widthAnchor),
             topAnchor.constraint(equalTo: view.topAnchor),
             heightAnchor.constraint(equalTo: view.heightAnchor),
-            ])
+        ])
     }
 
     func fitVerticalScrollView() {
@@ -46,31 +57,40 @@ public extension UIView {
             widthAnchor.constraint(equalTo: view.widthAnchor),
             topAnchor.constraint(equalTo: view.topAnchor),
             bottomAnchor.constraint(equalTo: view.bottomAnchor),
-            ])
+        ])
     }
 
-    func fillSuperview(edgeInsets: NSDirectionalEdgeInsets = .zero) {
+    func createFillSuperview(edgeInsets: NSDirectionalEdgeInsets = .zero) -> FillConstraints {
         guard let view = superview else {
-            return
+            fatalError("superview is not set")
         }
-        NSLayoutConstraint.activate([
-            leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: edgeInsets.leading),
-            trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -edgeInsets.trailing),
-            topAnchor.constraint(equalTo: view.topAnchor, constant: edgeInsets.top),
-            bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: -edgeInsets.bottom),
-            ])
+        return FillConstraints(
+            leading: leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: edgeInsets.leading),
+            trailing: trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -edgeInsets.trailing),
+            top: topAnchor.constraint(equalTo: view.topAnchor, constant: edgeInsets.top),
+            bottom: bottomAnchor.constraint(equalTo: view.bottomAnchor, constant: -edgeInsets.bottom)
+        )
     }
 
-    func fillSuperviewMargins(edgeInsets: NSDirectionalEdgeInsets = .zero) {
+    func fillSuperview(edgeInsets: NSDirectionalEdgeInsets = .zero) {
+        NSLayoutConstraint.activate(createFillSuperview(edgeInsets: edgeInsets))
+    }
+
+    func createFillSuperviewMargins(edgeInsets: NSDirectionalEdgeInsets = .zero) -> FillConstraints {
         guard let view = superview else {
-            return
+            fatalError("superview is not set")
         }
-        NSLayoutConstraint.activate([
-            leadingAnchor.constraint(equalTo: view.layoutMarginsGuide.leadingAnchor, constant: edgeInsets.leading),
-            trailingAnchor.constraint(equalTo: view.layoutMarginsGuide.trailingAnchor, constant: -edgeInsets.trailing),
-            topAnchor.constraint(equalTo: view.layoutMarginsGuide.topAnchor, constant: edgeInsets.top),
-            bottomAnchor.constraint(equalTo: view.layoutMarginsGuide.bottomAnchor, constant: -edgeInsets.bottom),
-            ])
+
+        return FillConstraints(
+            leading: leadingAnchor.constraint(equalTo: view.layoutMarginsGuide.leadingAnchor, constant: edgeInsets.leading),
+            trailing: trailingAnchor.constraint(equalTo: view.layoutMarginsGuide.trailingAnchor, constant: -edgeInsets.trailing),
+            top: topAnchor.constraint(equalTo: view.layoutMarginsGuide.topAnchor, constant: edgeInsets.top),
+            bottom: bottomAnchor.constraint(equalTo: view.layoutMarginsGuide.bottomAnchor, constant: -edgeInsets.bottom)
+        )
+    }
+
+    func fillSuperviewMargins(edgeInsets: NSDirectionalEdgeInsets = .zero) {
+        NSLayoutConstraint.activate(createFillSuperviewMargins(edgeInsets: edgeInsets))
     }
 
     func fillWithLowTrailingPriority() {
@@ -106,7 +126,12 @@ public extension UIView {
     var layoutHeight: CGFloat {
         return systemLayoutSizeFitting(UIView.layoutFittingCompressedSize).height
     }
+}
 
+public extension NSLayoutConstraint {
+    static func activate(_ constraints: FillConstraints) {
+        activate(constraints.all)
+    }
 }
 
 public protocol ViewInit: class {

diff --git a/dreiKit.podspec b/dreiKit.podspec
@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name             = "dreiKit"
-  s.version          = "1.0.4"
+  s.version          = "1.0.5"
   s.summary          = "A short description of dreiKit."
   s.homepage         = "https://github.com/dreipol/dreiKit"
   s.license          = { type: 'MIT', file: 'LICENSE' }