如何设置 a 的边框UIImage？
问问题
110713 次
16 回答
243
使用 OS > 3.0，您可以这样做：
//you need this import
#import <QuartzCore/QuartzCore.h>
[imageView.layer setBorderColor: [[UIColor blackColor] CGColor]];
[imageView.layer setBorderWidth: 2.0];
于 2010-06-10T21:00:28.710 回答
69
您可以通过创建一个新图像来做到这一点（也在您的其他帖子中回答了这个问题）：
- (UIImage*)imageWithBorderFromImage:(UIImage*)source;
{
CGSize size = [source size];
UIGraphicsBeginImageContext(size);
CGRect rect = CGRectMake(0, 0, size.width, size.height);
[source drawInRect:rect blendMode:kCGBlendModeNormal alpha:1.0];
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetRGBStrokeColor(context, 1.0, 0.5, 1.0, 1.0);
CGContextStrokeRect(context, rect);
UIImage *testImg = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return testImg;
}
此代码将在图像周围产生粉红色边框。但是，如果您只想显示边框，则使用图层UIImageView并设置其边框。
于 2009-08-31T19:14:43.233 回答
37
#import <QuartzCore/CALayer.h>
UIImageView *imageView = [UIImageView alloc]init];
imageView.layer.masksToBounds = YES;
imageView.layer.borderColor = [UIColor blackColor].CGColor;
imageView.layer.borderWidth = 1;
此代码可用于添加UIImageView视图边框。
于 2012-03-22T09:51:10.107 回答
13
imageView_ProfileImage.layer.cornerRadius =10.0f;
imageView_ProfileImage.layer.borderColor = [[UIColor blackColor] CGColor];
imageView_ProfileImage.layer.borderWidth =.4f;
imageView_ProfileImage.layer.masksToBounds = YES;
于 2015-02-24T13:26:56.777 回答
11
如果您知道图像的尺寸，那么向 UIImageView 的图层添加边框是 AFAIK 的最佳解决方案。事实上，你可以简单地将你的 imageView 设置为 x,y,image.size.width,image.size.height
如果您有一个固定大小的 ImageView，其中动态加载的图像正在调整大小（或缩放到 AspectFit），那么您的目标是将 imageview 的大小调整为新调整大小的图像。
执行此操作的最短方法：
// containerView is my UIImageView
containerView.layer.borderWidth = 7;
containerView.layer.borderColor = [UIColor colorWithRed:0.22 green:0.22 blue:0.22 alpha:1.0].CGColor;
// this is the key command
[containerView setFrame:AVMakeRectWithAspectRatioInsideRect(image.size, containerView.frame)];
但是要使用 AVMakeRectWithAspectRatioInsideRect，你需要添加这个
#import <AVFoundation/AVFoundation.h>
import 语句到您的文件中，并在您的项目中包含 AVFoundation 框架（与 SDK 捆绑在一起）。
于 2013-01-11T21:44:29.890 回答
8
您不能添加边框，但这会产生相同的效果。您还可以将本示例中名为 blackBG 的 UIView 制作为带有边框图像和空白中间的 UIImageView，然后您将拥有自定义图像边框，而不仅仅是黑色。
UIView *blackBG = [[UIView alloc] initWithFrame:CGRectMake(0,0,100,100)];
blackBG.backgroundColor = [UIColor blackColor];
UIImageView *myPicture = [[UIImageView alloc] initWithImage:
[UIImage imageNamed: @"myPicture.jpg"]];
int borderWidth = 10;
myPicture.frame = CGRectMake(borderWidth,
borderWidth,
blackBG.frame.size.width-borderWidth*2,
blackBG.frame.size.height-borderWidth*2)];
[blackBG addSubview: myPicture];
于 2009-08-31T02:53:14.040 回答
6
所有这些答案都可以正常工作，但在图像中添加一个矩形。假设您有一个形状（在我的例子中是蝴蝶）并且您想添加一个边框（红色边框）：
我们需要两个步骤： 1) 获取图像，转换为 CGImage，传递给使用 CoreGraphics 在上下文中绘制屏幕外的函数，并返回一个新的 CGImage
2）转回uiimage并绘制：
// remember to release object!
+ (CGImageRef)createResizedCGImage:(CGImageRef)image toWidth:(int)width
andHeight:(int)height
{
// create context, keeping original image properties
CGColorSpaceRef colorspace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate(NULL, width,
height,
8
4 * width,
colorspace,
kCGImageAlphaPremultipliedFirst
);
CGColorSpaceRelease(colorspace);
if(context == NULL)
return nil;
// draw image to context (resizing it)
CGContextSetInterpolationQuality(context, kCGInterpolationDefault);
CGSize offset = CGSizeMake(2,2);
CGFloat blur = 4;
CGColorRef color = [UIColor redColor].CGColor;
CGContextSetShadowWithColor ( context, offset, blur, color);
CGContextDrawImage(context, CGRectMake(0, 0, width, height), image);
// extract resulting image from context
CGImageRef imgRef = CGBitmapContextCreateImage(context);
CGContextRelease(context);
return imgRef;
}
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
CGRect frame = CGRectMake(0,0,160, 122);
UIImage * img = [UIImage imageNamed:@"butterfly"]; // take low res OR high res, but frame should be the low-res one.
imgV = [[UIImageView alloc]initWithFrame:frame];
[imgV setImage: img];
imgV.center = self.view.center;
[self.view addSubview: imgV];
frame.size.width = frame.size.width * 1.3;
frame.size.height = frame.size.height* 1.3;
CGImageRef cgImage =[ViewController createResizedCGImage:[img CGImage] toWidth:frame.size.width andHeight: frame.size.height ];
imgV2 = [[UIImageView alloc]initWithFrame:frame];
[imgV2 setImage: [UIImage imageWithCGImage:cgImage] ];
// release:
if (cgImage) CGImageRelease(cgImage);
[self.view addSubview: imgV2];
}
我添加了一只普通蝴蝶和一只红边大蝴蝶。
于 2012-04-08T17:25:57.063 回答
5
可以给 UIImageView 添加边框，然后根据图片大小改变 UIimageView 的大小：
#import <QuartzCore/QuartzCore.h>
// adding border to the imageView
[imageView.layer setBorderColor: [[UIColor whiteColor] CGColor]];
[imageView.layer setBorderWidth: 2.0];
// resize the imageView to fit the image size
CGSize size = [image size];
float factor = size.width / self.frame.size.width;
if (factor < size.height / self.frame.size.height) {
factor = size.height / self.frame.size.height;
}
CGRect rect = CGRectMake(0, 0, size.width/factor, size.height/factor);
imageView.frame = rect;
确保将 imageView 的原点设置为中心
于 2011-06-22T05:57:00.663 回答
2
您可以操作图像本身，但更好的方法是简单地添加一个包含 UIImageView 的 UIView，并将背景更改为黑色。然后将该容器视图的大小设置为比 UIImageView 大一点。
于 2009-08-31T02:45:50.290 回答
2
另一种方法是直接从设计师那里做。
选择您的图像并进入“显示身份检查器”。
在这里您可以手动添加“用户定义的运行时属性”：
layer.borderColor
layer.borderWidth
于 2015-01-15T13:59:00.910 回答
1
//你需要导入
QuartzCore/QuartzCore.h
& 然后为边框中的 ImageView
[imageView.layer setBorderColor: [[UIColor blackColor] CGColor]];
[imageView.layer setBorderWidth: 2.0];
[imageView.layer setCornerRadius: 5.0];
于 2013-10-20T11:58:04.733 回答
1
此功能将返回带有黑色边框的图像试试这个..希望这会对你有所帮助
- (UIImage *)addBorderToImage:(UIImage *)image frameImage:(UIImage *)blackBorderImage
{
CGSize size = CGSizeMake(image.size.width,image.size.height);
UIGraphicsBeginImageContext(size);
CGPoint thumbPoint = CGPointMake(0,0);
[image drawAtPoint:thumbPoint];
UIGraphicsBeginImageContext(size);
CGImageRef imgRef = blackBorderImage.CGImage;
CGContextDrawImage(UIGraphicsGetCurrentContext(), CGRectMake(0, 0, size.width,size.height), imgRef);
UIImage *imageCopy = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
CGPoint starredPoint = CGPointMake(0, 0);
[imageCopy drawAtPoint:starredPoint];
UIImage *imageC = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return imageC;
}
于 2013-01-12T08:57:49.443 回答
1
在 Swift 3 中，您可以对 UIImage 本身执行以下操作：
let size = CGSize(width: image.size.width, height: image.size.height)
UIGraphicsBeginImageContext(size)
let rect = CGRect(x: 0, y: 0, width: size.width, height: size.height)
image?.draw(in: rect, blendMode: .normal, alpha: 1.0)
let context = UIGraphicsGetCurrentContext()
context?.setStrokeColor(red: 0, green: 0, blue: 0, alpha: 1)
context?.stroke(rect)
let newImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
self.imageView.image = newImage
于 2017-01-18T23:21:00.523 回答
1
对于那些在 UIImage 上寻找即插即用解决方案的人，我将 CodyMace 的答案写为扩展。
用法：let outlined = UIImage(named: "something")?.outline()
extension UIImage {
func outline() -> UIImage? {
let size = CGSize(width: self.size.width, height: self.size.height)
UIGraphicsBeginImageContext(size)
let rect = CGRect(x: 0, y: 0, width: size.width, height: size.height)
self.draw(in: rect, blendMode: .normal, alpha: 1.0)
let context = UIGraphicsGetCurrentContext()
context?.setStrokeColor(red: 0, green: 0, blue: 0, alpha: 1)
context?.stroke(rect)
let newImage = UIGraphicsGetImageFromCurrentImageContext()
UIGraphicsEndImageContext()
return newImage
}
}
于 2017-07-05T19:48:56.747 回答
1
我创建了一个为 imageView h 添加边框的类。使用此类而不是 UIImageView。我给出了 4 的填充。您可以根据自己的意愿给出。
class UIBorderImageView: UIView {
private lazy var imageView: UIImageView = {
let imageView = UIImageView()
imageView.contentMode = .scaleAspectFit
imageView.translatesAutoresizingMaskIntoConstraints = false
return imageView
}()
override init(frame: CGRect) {
super.init(frame: frame)
self.backgroundColor = UIColor.White()
self.layer.borderColor = UIColor.GreyMedium().cgColor
self.layer.borderWidth = 1.0
self.layer.cornerRadius = 4.0
self.layer.masksToBounds = true
self.setUpViews()
}
required init?(coder aDecoder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
private func setUpViews(){
self.addSubview(imageView)
self.addConstraintsWithFormat(format: "H:|-4-[v0]-4-|", views: imageView)
self.addConstraintsWithFormat(format: "V:|-4-[v0]-4-|", views: imageView)
}
func configureImageViewWith(image:UIImage){
self.imageview.image = image
}}
于 2018-06-21T15:18:13.307 回答
-1
我使用这种方法在图像外添加边框。boderWidth您可以在常量中自定义边框宽度。
斯威夫特 3
func addBorderToImage(image : UIImage) -> UIImage {
let bgImage = image.cgImage
let initialWidth = (bgImage?.width)!
let initialHeight = (bgImage?.height)!
let borderWidth = Int(Double(initialWidth) * 0.10);
let width = initialWidth + borderWidth * 2
let height = initialHeight + borderWidth * 2
let data = malloc(width * height * 4)
let context = CGContext(data: data,
width: width,
height: height,
bitsPerComponent: 8,
bytesPerRow: width * 4,
space: (bgImage?.colorSpace)!,
bitmapInfo: CGImageAlphaInfo.premultipliedLast.rawValue);
context?.draw(bgImage!, in: CGRect(x: CGFloat(borderWidth), y: CGFloat(borderWidth), width: CGFloat(initialWidth), height: CGFloat(initialHeight)))
context?.setStrokeColor(UIColor.white.cgColor)
context?.setLineWidth(CGFloat(borderWidth))
context?.move(to: CGPoint(x: 0, y: 0))
context?.addLine(to: CGPoint(x: 0, y: height))
context?.addLine(to: CGPoint(x: width, y: height))
context?.addLine(to: CGPoint(x: width, y: 0))
context?.addLine(to: CGPoint(x: 0, y: 0))
context?.strokePath()
let cgImage = context?.makeImage()
let uiImage = UIImage(cgImage: cgImage!)
free(data)
return uiImage;
}
于 2017-09-20T11:32:16.127 回答