如何在iOS中切片图像和伸缩

Question

我需要拉伸图像左右中心半圆保持原样。中心还需要半圈

我尝试过切片概念，并尝试下面的代码

UIImage *image = self.imgBGBottom.image;
CGFloat capWidth =  floorf(image.size.width / 2) - 50;
CGFloat capHeight =  0;
UIImage *capImage = [image resizableImageWithCapInsets:
                     UIEdgeInsetsMake(capHeight, capWidth, capHeight, capWidth)];

[self.imgBGBottom setImage:capImage];

但它对我不起作用

请帮帮我。提前谢谢。

Answer 1

您正在使用功能，请使用- (UIImage *)stretchableImageWithLeftCapWidth:(NSInteger)leftCapWidth topCapHeight:(NSInteger)topCapHeight代替- (UIImage *)resizableImageWithCapInsets:(UIEdgeInsets)capInsets。

设置顶部左帽以拉伸图像，如下面的代码所述。

<强>目标C

UIImage *image = [UIImage imageNamed:@"test"];

CGFloat capTop =  50;  // top cap to keep half round as is
CGFloat capLeft = 5; // To repeat it or stretch equally.
UIImage *capImage = [image stretchableImageWithLeftCapWidth:capLeft topCapHeight:capTop];

<强>夫特

let image =  UIImage(named: "stretchableImage")

let capTop:Int =  50;  // top cap to keep half round as is
let capLeft:Int = 5; // To repeat it or stretch equally.
let capImage = image?.stretchableImage(withLeftCapWidth: capLeft, topCapHeight: capTop)

Alternet Solution

使用以下功能也可以实现相同的结果。

<强>目标C

UIImage *stretchedImage = [image resizableImageWithCapInsets:
                 UIEdgeInsetsMake(50, 50, 0, 50)];

<强>夫特

var stretchedImage = image?.resizableImage(withCapInsets: UIEdgeInsets(top: 50, left: 50, bottom: 0, right: 50), resizingMode: .stretch) 

  

注意：保持可伸缩图像尽可能小，否则无法使用较小的图像容器（ImageView，Button等）正确拉伸。你可以减少高度和现有图像的宽度。

Answer 2

试试这个

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