Question

我正在使用vfr-reader库编写PDF阅读器。要在横向中显示两个页面，我将每个页面呈现为自己的视图，然后将这两个视图添加到容器视图，然后将容器视图添加到滚动视图。每个视图的autoresizingMask设置为UIViewAutoresizingNone，contentMode设置为UIViewContentModeRedraw，autoresizingSubviews设置为所有视图的“NO”。

但仍然不知何故容器视图被自动调整以适应滚动视图的高度，我不知道这是在哪里发生的。我关心这个，因为，当自动化容器视图时，它的宽度变得比屏幕宽度大，并且我无法通过单次滑动滚动到接下来的两个页面（需要两次滑动），这很糟糕。我错过了什么？

编辑如果它有帮助的话会添加一些来。在ViewController中，我创建了一个Scroll View，其中包含以下选项：

theScrollView = [[ReaderScrollView alloc] initWithFrame:viewRect];
theScrollView.scrollsToTop = NO;
theScrollView.pagingEnabled = YES;
theScrollView.delaysContentTouches = NO;
theScrollView.showsVerticalScrollIndicator = NO;
theScrollView.showsHorizontalScrollIndicator = NO;
theScrollView.contentMode = UIViewContentModeRedraw;
theScrollView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
theScrollView.backgroundColor = [UIColor clearColor];
theScrollView.userInteractionEnabled = YES;
theScrollView.autoresizesSubviews = NO;
theScrollView.delegate = self;
[self.view addSubview:theScrollView];

当我正在绘制页面时，我正在向Scroll View添加一个UIView，这是以这种方式启动的：

if ((self = [super initWithFrame:frame]))
{
    self.autoresizesSubviews = YES;
    self.userInteractionEnabled = YES;
    self.contentMode = UIViewContentModeRedraw;
    self.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;       
    self.backgroundColor = [UIColor clearColor];

    theScrollView = [[ReaderScrollView alloc] initWithFrame:self.bounds]; // Not sure about this part - why is the 2nd scroll view added?
// this is the way its done in vfr reader

    theScrollView.scrollsToTop = NO;
    theScrollView.delaysContentTouches = NO;
    theScrollView.showsVerticalScrollIndicator = NO;
    theScrollView.showsHorizontalScrollIndicator = NO;
    theScrollView.contentMode = UIViewContentModeRedraw;
    theScrollView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;
    theScrollView.backgroundColor = [UIColor clearColor];
    theScrollView.userInteractionEnabled = YES;
    theScrollView.autoresizesSubviews = NO;
    theScrollView.bouncesZoom = YES;
    theScrollView.delegate = self;

    theContentView = [[ReaderContentPage alloc] initWithURL:fileURL page:page password:phrase landscape:(BOOL)isLandscape position:FALSE];
    CGRect viewRect = CGRectZero;
    viewRect.size.width = theContentView.bounds.size.width;
    viewRect.size.height = theContentView.bounds.size.height;    


    if( isLandscape){
        NSLog(@"Landscape detected in content view");
        if (theContentView == NULL)
        {
            theContentView = [[ReaderContentPage alloc] initWithURL:fileURL page:(page+1) password:phrase landscape:(BOOL)isLandscape position:FALSE];
            theContentView2 = NULL;
            viewRect.size.width = theContentView.bounds.size.width;
            viewRect.size.height = theContentView.bounds.size.height;    
        } else {
            if (page == 1)
                theContentView2 = NULL;
            else
                theContentView2 = [[ReaderContentPage alloc] initWithURL:fileURL page:(page+1) password:phrase landscape:(BOOL)isLandscape position:TRUE];
            if (theContentView2 != NULL)
               viewRect.size.width = theContentView.bounds.size.width*2;
        }            

    }       
    if (theContentView != nil) // Must have a valid and initialized content view
    {

        theContainerView = [[UIView alloc] initWithFrame:viewRect];


        theContainerView.autoresizesSubviews = NO;
        theContainerView.userInteractionEnabled = NO;
        theContainerView.contentMode = UIViewContentModeRedraw;            
        theContainerView.autoresizingMask = UIViewAutoresizingNone;
        theContainerView.backgroundColor = [UIColor whiteColor];


        theScrollView.contentSize = theContentView.bounds.size; // Content size same as view size


        theScrollView.contentOffset = CGPointMake((0.0f - CONTENT_INSET), (0.0f - CONTENT_INSET));
        theScrollView.contentInset = UIEdgeInsetsMake(CONTENT_INSET, CONTENT_INSET, CONTENT_INSET, CONTENT_INSET);

        theThumbView = [[ReaderContentThumb alloc] initWithFrame:theContentView.bounds]; // Page thumb view           

        [theContainerView addSubview:theThumbView]; // Add the thumb view to the container view

        [theContainerView addSubview:theContentView]; // Add the content view to the container view

        if(( isLandscape) && (theContentView2 != NULL)){            
             [theContainerView addSubview:theContentView2]; // Add the content view to the container view

        }           



        [theScrollView addSubview:theContainerView]; // Add the container view to the scroll view

        [self updateMinimumMaximumZoom]; // Update the minimum and maximum zoom scales

        theScrollView.zoomScale = theScrollView.minimumZoomScale; // Zoom to fit
    }

    [self addSubview:theScrollView]; // Add the scroll view to the parent container view   

    [theScrollView addObserver:self forKeyPath:@"frame" options:NSKeyValueObservingOptionNew context:NULL];

    self.tag = page; // Tag the view with the page number
}

return self;

以这种方式创建ReaderContentPage：

if ((self = [super initWithFrame:frame]))
    {
        self.autoresizesSubviews = NO;

        self.userInteractionEnabled = NO;
        self.clearsContextBeforeDrawing = NO;
        self.contentMode = UIViewContentModeRedraw;     
        self.autoresizingMask = UIViewAutoresizingNone;
        self.backgroundColor = [UIColor clearColor];

        view = self; // Return self
    }

Answer 1

在班级updateMinimumMaximumZoom中的ReaderContentView函数中：

使用单一视图计算适合屏幕的缩放比例，但在横向上应该从theContainerView计算。

尝试替换此代码

CGFloat zoomScale = ZoomScaleThatFits(targetRect.size, theContentView.bounds.size);

带

CGFloat zoomScale = ZoomScaleThatFits(targetRect.size, theContainerView.bounds.size);

Answer 2

UIScrollView中有一个contentMode属性，将其更改为UIViewContentModeCenter或其他内容以防止调整大小。

如何防止UIView调整大小以适应ScrollView高度（禁用自动调整大小）？

2 个答案: