嗨,VSN 首先从您的图像视图中剪切选定的部分
使用此代码
- (void)viewDidLoad
{
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
self.view.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"tactile_noise.png"]];
self.imageCropper = [[BJImageCropper alloc] initWithImage:[UIImage imageNamed:@"gavandme.jpg"] andMaxSize:CGSizeMake(1024, 600)];
[self.view addSubview:self.imageCropper];
self.imageCropper.center = self.view.center;
self.imageCropper.imageView.layer.shadowColor = [[UIColor blackColor] CGColor];
self.imageCropper.imageView.layer.shadowRadius = 3.0f;
self.imageCropper.imageView.layer.shadowOpacity = 0.8f;
self.imageCropper.imageView.layer.shadowOffset = CGSizeMake(1, 1);
[self.imageCropper addObserver:self forKeyPath:@"crop" options:NSKeyValueObservingOptionNew context:nil];
if (SHOW_PREVIEW) {
self.preview = [[UIImageView alloc] initWithFrame:CGRectMake(10,10,self.imageCropper.crop.size.width * 0.1, self.imageCropper.crop.size.height * 0.1)];
self.preview.image = [self.imageCropper getCroppedImage];
self.preview.clipsToBounds = YES;
self.preview.layer.borderColor = [[UIColor whiteColor] CGColor];
self.preview.layer.borderWidth = 2.0;
[self.view addSubview:self.preview];
}
}
检查这个例子
https://github.com/barrettj/BJImageCropper/downloads
或要裁剪选定的图像部分,请这样做
// Create the image from a png file
UIImage *image = [UIImage imageNamed:@"prgBinary.jpg"];
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
// Get size of current image
CGSize size = [image size];
// Frame location in view to show original image
[imageView setFrame:CGRectMake(0, 0, size.width, size.height)];
[[self view] addSubview:imageView];
[imageView release];
// Create rectangle that represents a cropped image
// from the middle of the existing image
CGRect rect = CGRectMake(size.width / 4, size.height / 4 ,
(size.width / 2), (size.height / 2));
// Create bitmap image from original image data,
// using rectangle to specify desired crop area
CGImageRef imageRef = CGImageCreateWithImageInRect([image CGImage], rect);
UIImage *img = [UIImage imageWithCGImage:imageRef];
CGImageRelease(imageRef);
// Create and show the new image from bitmap data
imageView = [[UIImageView alloc] initWithImage:img];
[imageView setFrame:CGRectMake(0, 200, (size.width / 2), (size.height / 2))];
[[self view] addSubview:imageView];
[imageView release];
参考这个
http://mobiledevelopertips.com/graphics/how-to-crop-an-image.html
或者要调整 uiiamgeview 的大小,请这样做
- (UIImage *)resizeImage:(UIImage*)image newSize:(CGSize)newSize
{
CGRect newRect = CGRectIntegral(CGRectMake(0, 0, newSize.width, newSize.height));
CGImageRef imageRef = image.CGImage;
UIGraphicsBeginImageContextWithOptions(newSize, NO, 0);
CGContextRef context = UIGraphicsGetCurrentContext();
// Set the quality level to use when rescaling
CGContextSetInterpolationQuality(context, kCGInterpolationHigh);
CGAffineTransform flipVertical = CGAffineTransformMake(1, 0, 0, -1, 0, newSize.height);
CGContextConcatCTM(context, flipVertical);
// Draw into the context; this scales the image
CGContextDrawImage(context, newRect, imageRef);
// Get the resized image from the context and a UIImage
CGImageRef newImageRef = CGBitmapContextCreateImage(context);
UIImage *newImage = [UIImage imageWithCGImage:newImageRef];
CGImageRelease(newImageRef);
UIGraphicsEndImageContext();
return newImage;
}
裁剪或调整图像大小以应用UIPanGestureRecognizer
UIPanGestureRecognizer *panRecognizer = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(move:)];
[panRecognizer setMinimumNumberOfTouches:1];
[panRecognizer setMaximumNumberOfTouches:1];
[panRecognizer setDelegate:self];
[holderView addGestureRecognizer:panRecognizer];
-(void)move:(id)sender {
[[[(UITapGestureRecognizer*)sender view] layer] removeAllAnimations];
[self.view bringSubviewToFront:[(UIPanGestureRecognizer*)sender view]];
CGPoint translatedPoint = [(UIPanGestureRecognizer*)sender translationInView:self.view];
if([(UIPanGestureRecognizer*)sender state] == UIGestureRecognizerStateBegan) {
firstX = [[sender view] center].x;
firstY = [[sender view] center].y;
}
translatedPoint = CGPointMake(firstX+translatedPoint.x, firstY+translatedPoint.y);
[[sender view] setCenter:translatedPoint];
if([(UIPanGestureRecognizer*)sender state] == UIGestureRecognizerStateEnded) {
CGFloat finalX = translatedPoint.x + (.35*[(UIPanGestureRecognizer*)sender velocityInView:self.view].x);
CGFloat finalY = translatedPoint.y + (.35*[(UIPanGestureRecognizer*)sender velocityInView:self.view].y);
if(UIDeviceOrientationIsPortrait([[UIDevice currentDevice] orientation])) {
if(finalX < 0) {
finalX = 0;
}
else if(finalX > 768) {
finalX = 768;
}
if(finalY < 0) {
finalY = 0;
}
else if(finalY > 1024) {
finalY = 1024;
}
}
else {
if(finalX < 0) {
finalX = 0;
}
else if(finalX > 1024) {
finalX = 768;
}
if(finalY < 0) {
finalY = 0;
}
else if(finalY > 768) {
finalY = 1024;
}
}
[UIView beginAnimations:nil context:NULL];
[UIView setAnimationDuration:.35];
[UIView setAnimationCurve:UIViewAnimationCurveEaseOut];
[[sender view] setCenter:CGPointMake(finalX, finalY)];
[UIView commitAnimations];
}
}