iPhone:CATiledLayer/UIScrollView 缩放后不会滚动,仅缩放到锚点

发布于 2024-08-31 15:42:51 字数 1898 浏览 3 评论 0原文

问题是...我正在使用 CA Tiled Layer 来显示大 jpg。视图加载正常,当我滚动时,它工作正常。但是,一旦我放大或缩小一次,它就会滚动到左上角(到锚点)并且根本不会滚动。缩放效果很好,但我就是无法滚动。

这是我的代码:

#import <QuartzCore/QuartzCore.h>
#import "PracticeViewController.h"

@implementation practiceViewController
//@synthesize image;

- (void)viewDidLoad
{


    NSString *path = [[NSBundle mainBundle] pathForResource:@"H-5" ofType:@"jpg"]; 
    NSData *data = [NSData dataWithContentsOfFile:path];
    image = [UIImage imageWithData:data];

    CGRect pageRect = CGRectMake(0,  0,  image.size.width, image.size.height);  


    CATiledLayer *tiledLayer = [CATiledLayer layer];
    tiledLayer.anchorPoint = CGPointMake(0.0f, 1.0f);
    tiledLayer.delegate = self;
    tiledLayer.tileSize = CGSizeMake(1000, 1000);
    tiledLayer.levelsOfDetail = 6; 
    tiledLayer.levelsOfDetailBias = 0;
    tiledLayer.bounds = pageRect; 
    tiledLayer.transform = CATransform3DMakeScale(1.0f, -1.0f, 0.3f);

    myContentView = [[UIView alloc] initWithFrame:self.view.bounds];
    [myContentView.layer addSublayer:tiledLayer];

    UIScrollView *scrollView = [[UIScrollView alloc] initWithFrame:self.view.bounds];
    scrollView.delegate = self;
    scrollView.contentSize = pageRect.size;
    scrollView.minimumZoomScale = .2;   
    scrollView.maximumZoomScale = 1; 
    [scrollView addSubview:myContentView];
    [self.view addSubview:scrollView];


}

- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView
{
    return myContentView;
}

- (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx
{
    NSString *path = [[NSBundle mainBundle] pathForResource:@"H-5" ofType:@"jpg"]; 
    NSData *data = [NSData dataWithContentsOfFile:path];
    image = [UIImage imageWithData:data];

    CGRect imageRect = CGRectMake (0.0, 0.0, image.size.width, image.size.height);
    CGContextDrawImage (ctx, imageRect, [image CGImage]);
}

@end

Here is the problem... I am using CA Tiled Layer to display a large jpg. The view loads okay, and when I go to scroll around, it works fine. However, as soon as I zoom in or out once, it scrolls to the top left (to the anchor point) and will not scroll at all. The zooming works fine, but I just cannot scroll.

Here is my code:

#import <QuartzCore/QuartzCore.h>
#import "PracticeViewController.h"

@implementation practiceViewController
//@synthesize image;

- (void)viewDidLoad
{


    NSString *path = [[NSBundle mainBundle] pathForResource:@"H-5" ofType:@"jpg"]; 
    NSData *data = [NSData dataWithContentsOfFile:path];
    image = [UIImage imageWithData:data];

    CGRect pageRect = CGRectMake(0,  0,  image.size.width, image.size.height);  


    CATiledLayer *tiledLayer = [CATiledLayer layer];
    tiledLayer.anchorPoint = CGPointMake(0.0f, 1.0f);
    tiledLayer.delegate = self;
    tiledLayer.tileSize = CGSizeMake(1000, 1000);
    tiledLayer.levelsOfDetail = 6; 
    tiledLayer.levelsOfDetailBias = 0;
    tiledLayer.bounds = pageRect; 
    tiledLayer.transform = CATransform3DMakeScale(1.0f, -1.0f, 0.3f);

    myContentView = [[UIView alloc] initWithFrame:self.view.bounds];
    [myContentView.layer addSublayer:tiledLayer];

    UIScrollView *scrollView = [[UIScrollView alloc] initWithFrame:self.view.bounds];
    scrollView.delegate = self;
    scrollView.contentSize = pageRect.size;
    scrollView.minimumZoomScale = .2;   
    scrollView.maximumZoomScale = 1; 
    [scrollView addSubview:myContentView];
    [self.view addSubview:scrollView];


}

- (UIView *)viewForZoomingInScrollView:(UIScrollView *)scrollView
{
    return myContentView;
}

- (void)drawLayer:(CALayer *)layer inContext:(CGContextRef)ctx
{
    NSString *path = [[NSBundle mainBundle] pathForResource:@"H-5" ofType:@"jpg"]; 
    NSData *data = [NSData dataWithContentsOfFile:path];
    image = [UIImage imageWithData:data];

    CGRect imageRect = CGRectMake (0.0, 0.0, image.size.width, image.size.height);
    CGContextDrawImage (ctx, imageRect, [image CGImage]);
}

@end

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梦中楼上月下 2024-09-07 15:42:51

请参阅上面列出的问题

See the above listed question

~没有更多了~
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