1、绘制手势截屏
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具体实现代码见 GitHub 源码 QExtension
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QTouchClipView.h
@interface QTouchClipView : UIView/**
* 创建手势截屏视图控件,获取截屏结果
*
* @param view 截取图片的视图控件
* @param result 手势截屏结果
*
* @return 手势截屏视图控件
*/
+ (instancetype)q_touchClipViewWithView:(UIView *)view
clipResult:(void (^)(UIImage * _Nullable image))result;@end -
QTouchClipView.m
@interface QTouchClipView ()/// 截取图片的视图控件
@property (nonatomic, strong) UIView *baseView;/// 滑动手势结果
@property (nonatomic, copy) void (^resultBlock)(UIImage * _Nullable);/// 触摸开始结束点
@property (nonatomic, assign) CGPoint startP;
@property (nonatomic, assign) CGPoint endP;@end@implementation QTouchClipView/// 创建手势截屏视图控件,获取截屏结果
+ (instancetype)q_touchClipViewWithView:(UIView *)baseView
clipResult:(void (^)(UIImage * _Nullable image))result { QTouchClipView *clipView = [[self alloc] initWithFrame:baseView.frame]; clipView.baseView = baseView;
clipView.resultBlock = result; return clipView;
}/// 初始化
- (instancetype)initWithFrame:(CGRect)frame { if (self = [super initWithFrame:frame]) {
self.backgroundColor = [[UIColor blackColor] colorWithAlphaComponent:0.5];
}
return self;
}/// 触摸开始
- (void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(nullable UIEvent *)event { // 获取触摸起始点位置
CGPoint startPoint = [touches.anyObject locationInView:self];
self.startP = startPoint;
}/// 触摸移动
- (void)touchesMoved:(NSSet<UITouch *> *)touches withEvent:(nullable UIEvent *)event { // 获取触摸点位置
CGPoint touchPoint = [touches.anyObject locationInView:self];
self.endP = touchPoint; // 刷新视图
[self setNeedsDisplay];
}/// 触摸结束
- (void)touchesEnded:(NSSet<UITouch *> *)touches withEvent:(nullable UIEvent *)event { // 截取屏幕图片
UIGraphicsBeginImageContextWithOptions(self.baseView.bounds.size, NO, 0); CGContextRef ctx = UIGraphicsGetCurrentContext();
[self.baseView.layer renderInContext:ctx]; UIImage *image = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); // 切割图片
CGFloat x = self.startP.x;
CGFloat y = self.startP.y;
CGFloat w = self.endP.x - x;
CGFloat h = self.endP.y - y; CGRect cutRect = CGRectMake(x * 2, y * 2, w * 2, h * 2); CGImageRef cgImage = CGImageCreateWithImageInRect(image.CGImage, cutRect);
UIImage *newImage = [[UIImage alloc] initWithCGImage:cgImage];
CGImageRelease(cgImage); // 返回截取结果
if (self.resultBlock) {
self.resultBlock(newImage);
} // 移除截取视图控件
[self removeFromSuperview];
self.startP = CGPointZero;
self.endP = CGPointZero; // 刷新视图
[self setNeedsDisplay];
}/// 触摸取消
- (void)touchesCancelled:(NSSet *)touches withEvent:(nullable UIEvent *)event {
[self touchesEnded:touches withEvent:event];
}/// 绘制触摸区域
- (void)drawRect:(CGRect)rect { CGFloat x = self.startP.x;
CGFloat y = self.startP.y;
CGFloat w = self.endP.x - x;
CGFloat h = self.endP.y - y; CGRect clipRect = CGRectMake(x, y, w, h); UIBezierPath *path = [UIBezierPath bezierPathWithRect:clipRect];
[[[UIColor whiteColor] colorWithAlphaComponent:0.2] setFill];
[path fill];
}@end -
ViewController.m
// 创建手势截屏视图
QTouchClipView *touchClipView = [QTouchClipView q_touchClipViewWithView:self.imageView
clipResult:^(UIImage * _Nullable image) { // 获取处理截屏结果
if (image) {
UIImageWriteToSavedPhotosAlbum(image, self, @selector(image:didFinishSavingWithError:contextInfo:), nil);
}
}];// 添加手势截屏视图
[self.view addSubview:touchClipView]; -
效果