Question

我的笔尖中有两个UIImageviews，其中一个是根据UISlider的值调整大小代码是： -

-(IBAction)sliderChanged:(UISlider*)slider{
    CGFloat scaleFactor=slider.value;

    markerImage.transform = CGAffineTransformMakeScale(scaleFactor,scaleFactor);
}

正确调整大小，但是当我通过这些代码将这些图像合并在一起时

UIImage *backImage=backgroundImage.image;
UIImage *markImage=markerImage.image;

UIGraphicsBeginImageContext(backImage.size);

[backImage drawAtPoint:CGPointMake(0,0)];
[markImage drawAtPoint:CGPointMake(0,0)];

UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

我合并了原始大小的图片，也就是说，标记图像在结果图像中出现在相同的维度中如何以正确的比例绘制标记图像谢谢

Answer 1

而不是drawAtPoint:，请使用drawInRect:(CGRect)rect。此外，需要使用滑块值。

假设sliderValue介于0和1之间，

CGRect rect = CGRectMake(0,0, markerImage.size.width*sliderValue, markerImage.size.height*sliderValue);
[markImage drawInRect:rect];

修改

CGFloat width = markerImage.size.width*sliderValue; CGFloat height = markerImage.size.height*sliderValue; CGRect rect = CGRectMake((markerImage.size.width-width)/2,(markerImage.size.height-height)/2, width, height); [markImage drawInRect:rect];

图像调整大小问题 - iPhone

1 个答案: