demo下载链接:https://share.weiyun.com/5sjcVi5
项目主要包含两个类 :GetScreenPointColor和UIImage+GetPointColor
-
GetScreenPointColor获取触摸点并截图 -
UIImage+GetPointColor获取图片某一点的颜色
GetScreenPointColor中包括3个方法:
-
getClickedColorWithTouches:withEvent:
当有一个或多个手指触摸事件在当前视图或window窗体中响应 -
getClickedPointWithTouches:withEvent:
获取当前点坐标 -
fullScreenshots:
获取截屏
GetScreenPointColor.h
定义枚举:
typedef enum : NSUInteger {
coordinate_window,
coordinate_current,
} Coordinate;
定义属性及方法:
@property (nonatomic, assign) Coordinate coordinate;
//当有一个或多个手指触摸事件在当前视图或window窗体中响应
- (UIColor *)getClickedColorWithTouches:(NSSet *)touches withEvent:(UIEvent *)event;
//获取当前点坐标
- (CGPoint)getClickedPointWithTouches:(NSSet *)touches withEvent:(UIEvent *)event;
//获取截屏
-(UIImage *)fullScreenshots;
GetScreenPointColor.m
定义属性
@property (nonatomic, strong) UIImage *screenImage;
getClickedColorWithTouches:withEvent:方法
//当有一个或多个手指触摸事件在当前视图或window窗体中响应
- (UIColor *)getClickedColorWithTouches:(NSSet *)touches withEvent:(UIEvent *)event
{
self.coordinate = coordinate_window;
CGPoint point = [self getClickedPointWithTouches:touches withEvent:event];
self.screenImage = [self fullScreenshots];
UIColor *currentColor = [self.screenImage colorAtPixel:point];
return currentColor;
}
getClickedPointWithTouches:withEvent:方法
//获取当前点坐标
- (CGPoint)getClickedPointWithTouches:(NSSet *)touches withEvent:(UIEvent *)event
{
//返回与当前接收者有关的所有的触摸对象
NSSet *allTouches = [event allTouches];
//视图中的所有对象
UITouch *touch = [allTouches anyObject];
CGPoint point = CGPointMake(0, 0);
if (self.coordinate == coordinate_current)
{
//返回触摸点在当前坐标系中的当前坐标
point = [touch locationInView:[touch view]];
}
if (self.coordinate == coordinate_window)
{
//返回触摸点在windows中的当前坐标
point = [touch locationInView:[touch window]];
}
return point;
}
fullScreenshots方法
//获取截屏
-(UIImage *)fullScreenshots
{
UIWindow *screenWindow = [[UIApplication sharedApplication] keyWindow];
UIGraphicsBeginImageContext(screenWindow.frame.size);//全屏截图，包括window
[screenWindow.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *viewImage = UIGraphicsGetImageFromCurrentImageContext();
return viewImage;
}
UIImage+GetPointColor.h
- (UIColor *)colorAtPixel:(CGPoint)point;
UIImage+GetPointColor.m
- (UIColor *)colorAtPixel:(CGPoint)point
{
//判断给定的点是否被一个CGRect包含
if (!CGRectContainsPoint(CGRectMake(0.0f, 0.0f, self.size.width, self.size.height), point))
{
return nil;
}
//颜色空间DeviceRGB
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
/*
data 指向要渲染的绘制内存的地址。这个内存块的大小至少是（bytesPerRow*height）个字节
width bitmap的宽度,单位为像素
height bitmap的高度,单位为像素
bitsPerComponent 内存中像素的每个组件的位数.例如，对于32位像素格式和RGB 颜色空间，你应该将这个值设为8
bytesPerRow bitmap的每一行在内存所占的比特数
colorspace bitmap上下文使用的颜色空间
bitmapInfo 指定bitmap是否包含alpha通道，像素中alpha通道的相对位置，像素组件是整形还是浮点型等信息的字符串。
*/
int bytesPerPixel = 4;
int bytesPerRow = bytesPerPixel * 1;
NSUInteger bitsPerComponent = 8;
unsigned char pixelData[4] = {0, 0, 0, 0};
CGContextRef context = CGBitmapContextCreate(pixelData, 1, 1, bitsPerComponent, bytesPerRow, colorSpace, kCGImageAlphaPremultipliedLast | kCGBitmapByteOrder32Big);
CGColorSpaceRelease(colorSpace);
CGContextSetBlendMode(context, kCGBlendModeCopy);
CGContextTranslateCTM(context, -point.x, point.y - self.size.height);
CGContextDrawImage(context, CGRectMake(0.0f, 0.0f, self.size.width, self.size.height), self.CGImage);
CGContextRelease(context);
CGFloat red = (CGFloat)pixelData[0] / 255.0f;
CGFloat green = (CGFloat)pixelData[1] / 255.0f;
CGFloat blue = (CGFloat)pixelData[2] / 255.0f;
CGFloat alpha = (CGFloat)pixelData[3] / 255.0f;
return [UIColor colorWithRed:red green:green blue:blue alpha:alpha];
}
在 ViewController 中的使用:
- (void)viewDidLoad
{
[super viewDidLoad];
UIImage *imgTest = [UIImage imageNamed:@"test.jpeg"];
UIImageView *imgViewTest = [[UIImageView alloc] initWithFrame:CGRectMake(50, 50, 300, 300)];
imgViewTest.image = imgTest;
imgViewTest.userInteractionEnabled = YES;
[self.view addSubview:imgViewTest];
self.viewShow = [[UIView alloc] initWithFrame:CGRectMake(50, 400, 100, 100)];
self.viewShow.layer.borderColor = [UIColor redColor].CGColor;
self.viewShow.layer.borderWidth = 1.0f;
[self.view addSubview:self.viewShow];
self.labX = [[UILabel alloc] initWithFrame:CGRectMake(CGRectGetMaxX(self.viewShow.frame) + 5, self.viewShow.frame.origin.y, 200, self.viewShow.frame.size.height / 2)];
[self.view addSubview:self.labX];
self.labX.text = @"X:";
self.labY = [[UILabel alloc] initWithFrame:CGRectMake(self.labX.frame.origin.x, CGRectGetMaxY(self.labX.frame), self.labX.frame.size.width, self.labX.frame.size.height)];
[self.view addSubview:self.labY];
self.labY.text = @"Y";
}
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
GetScreenPointColor *screen = [[GetScreenPointColor alloc] init];
screen.coordinate = coordinate_window;
CGPoint pointCurrent = [screen getClickedPointWithTouches:touches withEvent:event];
UIColor *colorCurrent = [screen getClickedColorWithTouches:touches withEvent:event];
self.viewShow.backgroundColor = colorCurrent;
self.labX.text = [NSString stringWithFormat:@"X:%.2f",pointCurrent.x];
self.labY.text = [NSString stringWithFormat:@"Y:%.2f",pointCurrent.y];
}
运行效果:https://share.weiyun.com/5Iewt73