给定两个 UIViews
有边框 UIPanGestureRecognizers
附在他们身上。
如果我拖动... UIView
左边 UIView
在右边,这是通常的行为。
寻找最简单的方法来实现这个功能!
一种方法是使用多个UIPanGestureRecognizers。同胞 层和 zPosition
. 为了达到效果,你要添加两个图层,一个是边框,一个是内容。而边框层有一个较小的 zPosition
比内容。当然,也可以用它来移动图层。UIPanGestureRecognizer
.
Swift。
import UIKit
class MergingView: UIView {
let borderLayer = CALayer()
let backgroundLayer = CALayer()
override func layoutSubviews() {
super.layoutSubviews()
addGestureRecognizer(UIPanGestureRecognizer(target: self, action: #selector(handlePan(_:))))
borderLayer.borderWidth = 5
borderLayer.frame = frame
borderLayer.zPosition = 10
borderLayer.borderColor = UIColor.black.cgColor
superview?.layer.addSublayer(borderLayer)
backgroundLayer.frame = CGRect(x: frame.origin.x + 5, y: frame.origin.y + 5, width: frame.width - 10, height: frame.height - 10)
backgroundLayer.zPosition = 20
backgroundLayer.backgroundColor = UIColor.white.cgColor
superview?.layer.addSublayer(backgroundLayer);
}
@objc func handlePan(_ recognizer: UIPanGestureRecognizer) {
CATransaction.begin()
CATransaction.setValue(kCFBooleanTrue, forKey: kCATransactionDisableActions)
let translation = recognizer.translation(in: self)
frame = self.frame.offsetBy(dx: translation.x, dy: translation.y)
recognizer.setTranslation(CGPoint.zero, in: self)
borderLayer.frame = borderLayer.frame.offsetBy(dx: translation.x, dy: translation.y)
backgroundLayer.frame = backgroundLayer.frame.offsetBy(dx: translation.x, dy: translation.y)
CATransaction.commit()
}
}
Objective-C头。
#import <UIKit/UIKit.h>
@interface MVMergingView : UIView
@end
Objective-C实现。
#import "MVMergingView.h"
@interface MVMergingView ()
@property (strong) CALayer *borderLayer;
@property (strong) CALayer *backgroundLayer;
@end
@implementation MVMergingView
- (void)layoutSubviews {
[super layoutSubviews];
[self addGestureRecognizer:[[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(handlePan:)]];
CALayer *borderLayer = [CALayer layer];
borderLayer.borderWidth = 5.f;
borderLayer.frame = self.frame;
borderLayer.zPosition = 10;
borderLayer.borderColor = UIColor.blackColor.CGColor;
self.borderLayer = borderLayer;
[self.superview.layer addSublayer:borderLayer];
CALayer *backgroundLayer = [CALayer layer];
backgroundLayer.frame = CGRectMake(self.frame.origin.x + 5.f, self.frame.origin.y + 5.f, self.frame.size.width - 10, self.frame.size.height - 10);
backgroundLayer.zPosition = 20;
backgroundLayer.backgroundColor = UIColor.whiteColor.CGColor;
self.backgroundLayer = backgroundLayer;
[self.superview.layer addSublayer:backgroundLayer];
}
- (void)handlePan:(UIPanGestureRecognizer *)recognizer {
[CATransaction begin];
[CATransaction setValue:(id)kCFBooleanTrue forKey:kCATransactionDisableActions];
CGPoint translation = [recognizer translationInView:self];
self.frame = CGRectOffset(self.frame, translation.x, translation.y);
[recognizer setTranslation:CGPointZero inView:self];
self.borderLayer.frame = CGRectOffset(self.borderLayer.frame, translation.x, translation.y);
self.backgroundLayer.frame = CGRectOffset(self.backgroundLayer.frame, translation.x, translation.y);
[CATransaction commit];
}
@end
似乎你要求 "合并 "而不是重叠,只是因为有边界才存在。如果没有边界,那么就不需要任何合并,你只需要把它们重叠起来。所以问题就变成了如何处理边界的问题。
我在想也许你可以有一个特殊的UIView子类(MergingView
?),它将作为2个视图的父视图:一个边框视图和一个内容视图。现在边框和内容分别在不同的视图中,"合并 "变得微不足道。
当我们放下 A
在...之上 B
,我们要做的就是把A的边框视图和内容视图给B(所以它们现在是B的子视图),然后把B的边框视图都发到后面。
然后你就可以继续和B进行更多的合并,程序是一样的。
这是否适合你的用例?如果需要,很乐意发代码。