圖片+捏手勢識別器

Question

我已經通過編程方式不使用故事板創建了一個視圖內的圖像視圖。我爲該視圖添加了捏手勢識別器......但它應該以特定的比例以各種方式捏住圖像？有沒有辦法做到這一點？

-(void)handlePinchWithGestureRecognizer:(UIPinchGestureRecognizer *)pinchGestureRecognizer{ 

CGFloat lastScale = 1.0; 
if([pinchGestureRecognizer state] == UIGestureRecognizerStateBegan) { 
    // Reset the last scale, necessary if there are multiple objects with different scales 
    lastScale = [pinchGestureRecognizer scale]; 
} 

if ([pinchGestureRecognizer state] == UIGestureRecognizerStateBegan || 
    [pinchGestureRecognizer state] == UIGestureRecognizerStateChanged) { 

    CGFloat currentScale = [[[pinchGestureRecognizer view].layer valueForKeyPath:@"transform.scale"] floatValue]; 

    // Constants to adjust the max/min values of zoom 
    const CGFloat kMaxScale = 2.0; 
    const CGFloat kMinScale = 1.0; 

    CGFloat newScale = 1 - (lastScale - [pinchGestureRecognizer scale]); 
    newScale = MIN(newScale, kMaxScale/currentScale); 
    newScale = MAX(newScale, kMinScale/currentScale); 
    self.documentImageView.transform = CGAffineTransformScale(self.documentImageView.transform, newScale, newScale); 

    lastScale = [pinchGestureRecognizer scale]; // Store the previous scale factor for the next pinch gesture call 
} 
} 
- (void)viewDidAppear:(BOOL)animated { 
[super viewDidAppear:animated]; 

UIPinchGestureRecognizer *pinchGestureRecognizer = [[UIPinchGestureRecognizer alloc] initWithTarget:self action:@selector(handlePinchWithGestureRecognizer:)]; 
[self.documentImage addGestureRecognizer:pinchGestureRecognizer]; 
} 

//

- (void)setExtractedImageForTableView:(UIImage *)extractedImage { 
self.documentImageView.image = nil; 
self.documentImageView = nil; 
self.documentImageView = [[UIImageView alloc] initWithImage:extractedImage]; 
self.documentImageView.contentMode = UIViewContentModeScaleAspectFit; 
if (!CGSizeEqualToSize(extractedImage.size, CGSizeZero)) { 
    self.documentImageView.frame = CGRectMake(CGRectGetMinX(self.view.frame), CGRectGetMinY(self.tableView.frame) + 70, CGRectGetWidth(self.view.frame), (extractedImage.size.height/extractedImage.size.width) * CGRectGetWidth(self.view.frame)); 
    self.segmentedView.frame = self.documentImage.frame; 
    [self.segmentedView addSubview:self.segment]; 
    [self.segmentedView addSubview:self.documentImageView]; 
    [self.tableView.tableHeaderView addSubview:self.segment]; 
    [self.tableView.tableHeaderView addSubview:self.documentImageView]; 
    CGRect frame = self.documentImageView.frame; 
    frame.size.height = self.documentImageView.frame.size.height + 100; 
    self.tableView.frame = CGRectMake(0, 0, 400, 300); 
    self.tableView.tableHeaderView.frame = frame; 
} 
} 

Answer 1

我覺得你只是錯過添加以下行

[self.documentImageView setUserInteractionEnabled:YES]; 

希望這會工作。