Question

即时通讯使用其他人的缩放手势代码进行缩放，效果很好，但在我的照片编辑应用中缩放我的图像，一旦用户按下完成缩放，我需要反映和保存更改或者说我需要的其他方式如果有人使用缩放比例，实际放大和裁剪的图像。我想我可以使用他们缩放的数量* uigraphicsbeginimagecontext的帧大小，但该策略不起作用，因为当用户缩放图像并点击完成按钮时图像被保存得更小，因为现在非常大的尺寸被挤进视图什么时候我真正想要的东西裁掉任何残羹剩饭而不做任何适合。

- (IBAction)pinchGest:(UIPinchGestureRecognizer *)sender{


if (sender.state == UIGestureRecognizerStateEnded
    || sender.state == UIGestureRecognizerStateChanged) {
    NSLog(@"sender.scale = %f", sender.scale);

    CGFloat currentScale = self.activeImageView.frame.size.width / self.activeImageView.bounds.size.width;
    CGFloat newScale = currentScale * sender.scale;

    if (newScale < .5) {
        newScale = .5;
    }
    if (newScale > 4) {
        newScale = 4;
    }

    CGAffineTransform transform = CGAffineTransformMakeScale(newScale, newScale);
    self.activeImageView.transform = transform;
    scalersOfficialChange = newScale;
    sender.scale = 1;

}
}

- (IBAction)doneMoverViewButtonPressed:(UIButton *)sender {
// turn off ability to move & scale
moverViewActive = NO;

NSLog(@"%f %f",dragOfficialChange.x,dragOfficialChange.y);
NSLog(@"%f",rotationOfficialChange);
NSLog(@"%f",scalersOfficialChange);


//problem area below...
CGSize newSize = CGSizeMake(self.activeImageView.bounds.size.width * scalersOfficialChange, self.activeImageView.bounds.size.height * scalersOfficialChange );

UIGraphicsBeginImageContext(newSize);

[self.activeImageView.image drawInRect:CGRectMake(dragOfficialChange.x, dragOfficialChange.y, self.layerContainerView.bounds.size.width, self.layerContainerView.bounds.size.height)];

self.activeImageView.image = UIGraphicsGetImageFromCurrentImageContext();


UIGraphicsEndImageContext();

[self hideMoveViewerAnimation];

//resets activeimageview coords
CGRect myFrame = self.layerContainerView.bounds;
myFrame.origin.x = 0;
myFrame.origin.y = 0;
self.activeImageView.frame = myFrame;

//reset changes values
dragOfficialChange.x = 0;
dragOfficialChange.y = 0;
rotationOfficialChange = 0;
scalersOfficialChange = 0;

}

Answer 1

首先，您能否更清楚地提出问题？我建议你想用矩形绘制你的图像，不想挤它，我是对的吗？

然后让我们试试这个方法：

//The method: drawInRect:(CGRect) will scale your pic and squeeze it to fit the Rect area
//So if you dont want to scale your pic, you can use the method below
[image drawAsPatternInRect：(CGRect)_rect];
//This method would not scale your image and cut the needless part

IOS UIImage Scale和Crop，放大实际上使图像更小？

1 个答案: