implement optional priorities to constraint extension methods

deltachat-ios/Extensions/UIView+Extensions.swift

@@ -60,8 +60,8 @@ internal extension UIView {
         return constraintAlignTopTo(view, paddingTop: 0.0)
     }
 
-    func constraintAlignTopTo(_ view: UIView, paddingTop: CGFloat = 0.0) -> NSLayoutConstraint {
-        return NSLayoutConstraint(
+    func constraintAlignTopTo(_ view: UIView, paddingTop: CGFloat = 0.0, priority: UILayoutPriority? = .none) -> NSLayoutConstraint {
+        let constraint = NSLayoutConstraint(
             item: self,
             attribute: .top,
             relatedBy: .equal,
@@ -69,10 +69,14 @@ internal extension UIView {
             attribute: .top,
             multiplier: 1.0,
             constant: paddingTop)
+        if let priority = priority {
+            constraint.priority = priority
+        }
+        return constraint
     }
 
-    func constraintAlignBottomTo(_ view: UIView, paddingBottom: CGFloat = 0.0) -> NSLayoutConstraint {
-        return NSLayoutConstraint(
+    func constraintAlignBottomTo(_ view: UIView, paddingBottom: CGFloat = 0.0, priority: UILayoutPriority? = .none) -> NSLayoutConstraint {
+        let constraint = NSLayoutConstraint(
             item: self,
             attribute: .bottom,
             relatedBy: .equal,
@@ -80,10 +84,14 @@ internal extension UIView {
             attribute: .bottom,
             multiplier: 1.0,
             constant: -paddingBottom)
+        if let priority = priority {
+            constraint.priority = priority
+        }
+        return constraint
     }
 
-    func constraintAlignLeadingTo(_ view: UIView, paddingLeading: CGFloat = 0.0) -> NSLayoutConstraint {
-        return NSLayoutConstraint(
+    func constraintAlignLeadingTo(_ view: UIView, paddingLeading: CGFloat = 0.0, priority: UILayoutPriority? = .none) -> NSLayoutConstraint {
+        let constraint = NSLayoutConstraint(
             item: self,
             attribute: .leading,
             relatedBy: .equal,
@@ -91,10 +99,14 @@ internal extension UIView {
             attribute: .leading,
             multiplier: 1.0,
             constant: paddingLeading)
+        if let priority = priority {
+            constraint.priority = priority
+        }
+        return constraint
     }
 
-    func constraintAlignTrailingTo(_ view: UIView, paddingTrailing: CGFloat = 0.0) -> NSLayoutConstraint {
-        return NSLayoutConstraint(
+    func constraintAlignTrailingTo(_ view: UIView, paddingTrailing: CGFloat = 0.0, priority: UILayoutPriority? = .none) -> NSLayoutConstraint {
+        let constraint = NSLayoutConstraint(
             item: self,
             attribute: .trailing,
             relatedBy: .equal,
@@ -102,10 +114,14 @@ internal extension UIView {
             attribute: .trailing,
             multiplier: 1.0,
             constant: -paddingTrailing)
+        if let priority = priority {
+            constraint.priority = priority
+        }
+        return constraint
     }
 
-    func constraintToBottomOf(_ view: UIView, paddingTop: CGFloat = 0.0) -> NSLayoutConstraint {
-        return NSLayoutConstraint(
+    func constraintToBottomOf(_ view: UIView, paddingTop: CGFloat = 0.0, priority: UILayoutPriority? = .none) -> NSLayoutConstraint {
+        let constraint = NSLayoutConstraint(
             item: self,
             attribute: .top,
             relatedBy: .equal,
@@ -113,10 +129,14 @@ internal extension UIView {
             attribute: .bottom,
             multiplier: 1.0,
             constant: paddingTop)
+        if let priority = priority {
+            constraint.priority = priority
+        }
+        return constraint
     }
 
-    func constraintToTrailingOf(_ view: UIView, paddingLeading: CGFloat = 0.0) -> NSLayoutConstraint {
-        return NSLayoutConstraint(
+    func constraintToTrailingOf(_ view: UIView, paddingLeading: CGFloat = 0.0, priority: UILayoutPriority? = .none) -> NSLayoutConstraint {
+        let constraint = NSLayoutConstraint(
             item: self,
             attribute: .leading,
             relatedBy: .equal,
@@ -124,35 +144,55 @@ internal extension UIView {
             attribute: .trailing,
             multiplier: 1.0,
             constant: paddingLeading)
+        if let priority = priority {
+            constraint.priority = priority
+        }
+        return constraint
     }
 
 
-    func constraintCenterXTo(_ view: UIView, paddingX: CGFloat = 0.0) -> NSLayoutConstraint {
-        return NSLayoutConstraint(item: self,
+    func constraintCenterXTo(_ view: UIView, paddingX: CGFloat = 0.0, priority: UILayoutPriority? = .none) -> NSLayoutConstraint {
+        let constraint = NSLayoutConstraint(item: self,
                                   attribute: .centerX,
                                   relatedBy: .equal,
                                   toItem: view,
                                   attribute: .centerX,
                                   multiplier: 1.0,
                                   constant: paddingX)
+        if let priority = priority {
+            constraint.priority = priority
+        }
+        return constraint
     }
 
-    func constraintCenterYTo(_ view: UIView, paddingY: CGFloat = 0.0) -> NSLayoutConstraint {
-        return NSLayoutConstraint(item: self,
+    func constraintCenterYTo(_ view: UIView, paddingY: CGFloat = 0.0, priority: UILayoutPriority? = .none) -> NSLayoutConstraint {
+        let constraint = NSLayoutConstraint(item: self,
                                   attribute: .centerY,
                                   relatedBy: .equal,
                                   toItem: view,
                                   attribute: .centerY,
                                   multiplier: 1.0,
                                   constant: paddingY)
+        if let priority = priority {
+            constraint.priority = priority
+        }
+        return constraint
     }
 
-    func constraintHeightTo(_ height: CGFloat) -> NSLayoutConstraint {
-        return heightAnchor.constraint(equalToConstant: height)
+    func constraintHeightTo(_ height: CGFloat, priority: UILayoutPriority? = .none) -> NSLayoutConstraint {
+        let constraint = heightAnchor.constraint(equalToConstant: height)
+        if let priority = priority {
+            constraint.priority = priority
+        }
+        return constraint
     }
 
-    func constraintWidthTo(_ width: CGFloat) -> NSLayoutConstraint {
-       return  widthAnchor.constraint(equalToConstant: width)
+    func constraintWidthTo(_ width: CGFloat, priority: UILayoutPriority? = .none) -> NSLayoutConstraint {
+        let constraint = widthAnchor.constraint(equalToConstant: width)
+        if let priority = priority {
+            constraint.priority = priority
+        }
+        return constraint
     }
 
     func fillSuperview() {