ios - 如何使用添加的 UIBezierPath 保存图像？

Question

我想用我愚蠢的绘图保存图像，但是当我保存图像时，只有原始图像被保存。

我期望的图像是这样的:

这是我的图片保存代码:

UIImageWriteToSavedPhotosAlbum(_imgShow.image,
                                   nil,
                                   nil,
                                   nil);

这是我的 UIImageView 自定义类:

    -(void)awakeFromNib
{
//    drawingView=[[UIView alloc]initWithFrame:self.bounds];
//    drawingView.backgroundColor=[UIColor clearColor];
//    [self addSubview:drawingView];
    clearBeizer=[[NSMutableArray alloc]init];
    [self updateMask];
}
-(void)updateMask
{
    CALayer *maskLayer=[CALayer layer];
    maskLayer.geometryFlipped=YES;
    maskLayer.contents=(id)self.image.CGImage;
    switch (self.contentMode)
    {
        case UIViewContentModeScaleToFill:
            maskLayer.contentsGravity = kCAGravityResize;
            break;
        case UIViewContentModeScaleAspectFit:
            maskLayer.contentsGravity = kCAGravityResizeAspect;
            break;
        case UIViewContentModeScaleAspectFill:
            maskLayer.contentsGravity = kCAGravityResizeAspectFill;
            break;
        case UIViewContentModeCenter:
            maskLayer.contentsGravity = kCAGravityCenter;
            break;
        case UIViewContentModeTop:
            maskLayer.contentsGravity = kCAGravityTop;
            break;
        case UIViewContentModeBottom:
            maskLayer.contentsGravity = kCAGravityBottom;
            break;
        case UIViewContentModeLeft:
            maskLayer.contentsGravity = kCAGravityLeft;
            break;
        case UIViewContentModeRight:
            maskLayer.contentsGravity = kCAGravityRight;
            break;
        case UIViewContentModeTopLeft:
            maskLayer.contentsGravity = kCAGravityTopLeft;
            break;
        case UIViewContentModeTopRight:
            maskLayer.contentsGravity = kCAGravityTopRight;
            break;
        case UIViewContentModeBottomLeft:
            maskLayer.contentsGravity = kCAGravityBottomLeft;
            break;
        case UIViewContentModeBottomRight:
            maskLayer.contentsGravity = kCAGravityBottomRight;
            break;
        default:
            break;

    }
    maskLayer.frame=self.bounds;
//    drawingView.layer.mask=maskLayer;
    self.layer.mask=maskLayer;

}
-(void)setImage:(UIImage *)image
{
    [super setImage:image];
    [self updateMask];
}
-(void)layoutSubviews
{
    [super layoutSubviews];
//    drawingView.frame=self.bounds;
//    drawingView.layer.mask.frame=drawingView.bounds;
    self.frame=self.bounds;
    self.layer.mask.frame=self.bounds;
}
-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [[event allTouches] anyObject];
    startingPoint = [touch locationInView:self];

}
-(void)touchesMoved:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event
{
    UITouch *touch = [[event allTouches] anyObject];
    touchPoint = [touch locationInView:self];

    if (!CGPointEqualToPoint(startingPoint, CGPointZero))
    {
        UIBezierPath *path = [UIBezierPath bezierPath];
        [path moveToPoint:CGPointMake(touchPoint.x,touchPoint.y)];
        [path addLineToPoint:CGPointMake(startingPoint.x,startingPoint.y)];

        CAShapeLayer *shapeLayer = [CAShapeLayer layer];
        shapeLayer.path = [path CGPath];
        shapeLayer.strokeColor = [[UIColor blueColor] CGColor];
        if([UIDevice currentDevice].userInterfaceIdiom ==UIUserInterfaceIdiomPad)
        {
            shapeLayer.lineWidth = 7.0;
        }
        else
        {
            shapeLayer.lineWidth = 5.0;

        }

        shapeLayer.fillColor = [[UIColor redColor] CGColor];
        [self.layer addSublayer:shapeLayer];
        [clearBeizer addObject:shapeLayer];
    }
    startingPoint=touchPoint;

    //    [arrLayer addObject:shapeLayer];
    NSLog(@"Touch moving point =x : %f Touch moving point =y : %f", touchPoint.x, touchPoint.y);
}

这是我的自定义类。

Answer 1

您只是在更改图像的渲染，而不是图像本身的数据，然后写入该数据并期望它反射(reflect) View 的渲染。

您可以使用 snapshotViewAfterScreenUpdates:结果来自this question管理您实际想要实现的目标。