画板
#import "DrawView.h"
@interface DrawView ()
@property(nonatomic,retain)NSMutableArray * paths;
@property(nonatomic,retain)UIBezierPath *path;
@end
@implementation DrawView
-(NSMutableArray*)paths
{
if (!_paths)
{
_paths=[NSMutableArray array];
}
return _paths;
}
-(instancetype)initWithFrame:(CGRect)frame
{
if (self==[super initWithFrame:frame])
{
UIPanGestureRecognizer*pan=[[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(pan:)];
[self addGestureRecognizer:pan];
}
return self;
}
-(void)pan:(UIPanGestureRecognizer*)pan
{
//获取当前手指触摸点
CGPoint currentP = [pan locationInView:self];
//获取开始点
if (pan.state == UIGestureRecognizerStateBegan)
{
_path = [UIBezierPath bezierPath];
//设置路径的起点
[_path moveToPoint:currentP];
//保存描述好的路径
[self.paths addObject:_path];
}
// 手指拖动 添加线到当前触摸点
[_path addLineToPoint:currentP];
//重绘
[self setNeedsDisplay];
}
//只要调用这个方法，就会把之前绘制的东西全部清掉，重新绘制
- (void)drawRect:(CGRect)rect
{
for (UIBezierPath*path in self.paths)
{
[path stroke];
}
}
图片裁剪
@interface CompanyViewController ()
@property(nonatomic,retain)UIImageView*imageView;
@property(nonatomic,assign)CGPoint startP;
@property(nonatomic,retain)UIView*clipView;
@end
@implementation CompanyViewController
- (void)viewDidLoad
{
[super viewDidLoad];
self.view.backgroundColor=[UIColor whiteColor];
self.title=@"图片裁剪";
_imageView=[[UIImageView alloc]initWithFrame:self.view.bounds];
_imageView.image=[UIImage imageNamed:@"qidong"];
[self.view addSubview:_imageView];
_clipView=[[UIView alloc]init];
_clipView.backgroundColor=[[UIColor blackColor] colorWithAlphaComponent:0.3];
[self.view addSubview:_clipView];
UIPanGestureRecognizer*pan = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(pan:)];
[self.view addGestureRecognizer:pan];
}
-(void)pan:(UIPanGestureRecognizer*)pan
{
if (pan.state == UIGestureRecognizerStateBegan)
{
_startP = [pan locationInView:_imageView];
}
else if (pan.state == UIGestureRecognizerStateChanged)
{
CGPoint endA = [pan locationInView:_imageView];
CGFloat w = endA.x - _startP.x;
CGFloat h = endA.y - _startP.y;
//获取截取范围
CGRect clipRect = CGRectMake(_startP.x, _startP.y, w, h);
//生成截屏的view
self.clipView.frame = clipRect;
}
else if (pan.state == UIGestureRecognizerStateEnded)
{
//图片裁剪，生成一张新的图片
//开启上下文
//如果不透明，默认超出裁剪区域会变成黑色，通常都是透明
UIGraphicsBeginImageContextWithOptions(_imageView.bounds.size, NO, 0);
//设置裁剪区域
UIBezierPath *path = [UIBezierPath bezierPathWithRect:_clipView.frame];
[path addClip];
//获取上下文
CGContextRef context = UIGraphicsGetCurrentContext();
//把控件上的内容渲染到上下文
[_imageView.layer renderInContext:context];
//生成一张新的图片
_imageView.image = UIGraphicsGetImageFromCurrentImageContext();
//关闭
UIGraphicsEndImageContext();
}
}
图片擦除
@interface CompanyViewController ()
@property(nonatomic,retain)UIImageView*imageView;
@end
@implementation CompanyViewController
- (void)viewDidLoad
{
[super viewDidLoad];
self.view.backgroundColor=[UIColor whiteColor];
self.title=@"图片水印";
_imageView=[[UIImageView alloc]initWithFrame:self.view.bounds];
_imageView.image=[UIImage imageNamed:@""];
[self.view addGestureRecognizer:_imageView];
UIPanGestureRecognizer*pan = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(pan:)];
[self.view addGestureRecognizer:pan];
}
-(void)pan:(UIPanGestureRecognizer*)pan
{
//获取当前点
CGPoint curentP = [pan locationInView:self.view];
//获取擦除的矩形范围
CGFloat wh = 30;
CGFloat x = curentP.x - wh*0.5;
CGFloat y = curentP.y - wh*0.5;
CGRect rect = CGRectMake(x, y, wh, wh);
//开启上下文
UIGraphicsBeginImageContextWithOptions(self.view.bounds.size, NO, 0);
//获取上下文
CGContextRef context = UIGraphicsGetCurrentContext();
//控件的layer渲染上去
[_imageView.layer renderInContext:context];
//擦除图片
CGContextClearRect(context, rect);
//生存一张图片
UIImage * image = UIGraphicsGetImageFromCurrentImageContext();
_imageView.image = image;
//关闭上下文
UIGraphicsEndImageContext();
}
方形图片生产圆形头像
+(UIImage*)imageWithCilpImage:(UIImage*)image borderWidth:(CGFloat)borderWidth borderColor:(UIColor*)color
{
//图片的宽度和高度
CGFloat imageWH = image.size.width;
//圆形的宽度和高度
CGFloat ovalWH = imageWH + 2*borderWidth;
//开启上下文
UIGraphicsBeginImageContextWithOptions(CGSizeMake(ovalWH, ovalWH), NO, 0);
//画大圆
UIBezierPath * path=[UIBezierPath bezierPathWithOvalInRect:CGRectMake(0, 0, ovalWH, ovalWH)];
//设置圆环颜色
[color set];
//颜色填充
[path fill];
//设置裁剪区域
UIBezierPath *clipPath = [UIBezierPath bezierPathWithOvalInRect:CGRectMake(borderWidth, borderWidth, imageWH, imageWH)];
//图片剪切
[clipPath addClip];
//绘制图片
[image drawAtPoint:CGPointMake(borderWidth, borderWidth)];
//获取图片
UIImage *clipImage = UIGraphicsGetImageFromCurrentImageContext();
//关闭上下文
UIGraphicsEndImageContext();
return clipImage;
}
手机截屏
+(UIImage*)imageWithCaputureView:(UIView*)view
{
//开启位图上下文
UIGraphicsBeginImageContextWithOptions(view.bounds.size, NO, 0);
//获取上下文
CGContextRef context = UIGraphicsGetCurrentContext();
//把控件上的图层渲染到上下文,layer只能渲染
[view.layer renderInContext:context];
//生成一张图片
UIImage * image = UIGraphicsGetImageFromCurrentImageContext();
//关闭上下文
UIGraphicsEndImageContext();
return image;
}
图片水印
+(UIImage*)imageWithWaterImage:(UIImage*)image waterTitle:(NSString*)title waterAttributes:(NSDictionary*)attributes
{
//0.获取上下文，之前的上下文都是在view的drawRect方法中获取（跟view相关联的上下文layer上下文）
//此时我们需要绘制图片到新的图片上，因此需要用到位图上下文
//怎么获取位图上下文，注意位图上下文的获取方式跟layer上下文不一样，位图上下文需要我们手动创建。
//开启一个位图上下文，注意位图上下文跟view无关联，所以不需要drawRect
//size:位图上下文的尺寸（新图片的尺寸）
//opaque:不透明度 YES:不透明 NO:透明 一般都是透明的上下文
//scale:缩放比例 0:不缩放
UIGraphicsBeginImageContextWithOptions(image.size,NO, 0);
//1.绘制原生的图片
[image drawAtPoint:CGPointZero];
//2.给原生的图片添加文字
NSString*str = title;
[str drawAtPoint:CGPointMake(image.size.width-80, image.size.height-30) withAttributes:attributes];
//3.从上下文获取生成的图片
UIImage*imageWater = UIGraphicsGetImageFromCurrentImageContext();
//4.关闭上下文
UIGraphicsEndImageContext();
return imageWater;
}