启用页面并更改设备旋转/方向的UIScrollView(MADNESS)

时间:2010-03-26 17:23:46

标签: objective-c cocoa-touch ios uiscrollview uiinterfaceorientation

我很难做到这一点。

我有一个UIScrollView,启用了分页功能。它由视图控制器(MainViewController)管理,每个页面由PageViewController管理,其视图作为scrollView的子视图添加到适当的偏移量。滚动是左右,适用于标准方向的iPhone应用程序。效果很好。基本上就像Apple提供的样本一样,也像iPhone提供的Weather应用程序一样。

然而,当我尝试支持其他方向时,事情并不能很好地发挥作用。我用这种方法支持MainViewController和PageViewController中的每个方向:

- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
     return YES;
}

然而,当我旋转设备时,我的页面变得非常歪斜,并且有很多绘图故障,特别是如果只加载了一些页面,然后我旋转,然后滚动更多等等...非常凌乱

我告诉我的观点是支持使用

自动调整大小
 theView.autoresizingMask = UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleHeight;

但无济于事。它似乎只是拉伸和扭曲了我的观点。

在我的MainViewController中,我添加了这一行,试图调整所有页面的视图:

- (void)didRotateFromInterfaceOrientation:(UIInterfaceOrientation)fromInterfaceOrientation {
self.scrollView.contentSize = CGSizeMake(self.scrollView.frame.size.width * ([self.viewControllers count]), self.scrollView.frame.size.height);

    for (int i = 0; i < [self.viewControllers count]; i++) {
        PageViewController *controller = [self.viewControllers objectAtIndex:i];
        if ((NSNull *)controller == [NSNull null])
            continue;

        NSLog(@"Changing frame: %d", i);
        CGRect frame = self.scrollView.frame;
        frame.origin.x = frame.size.width * i;
        frame.origin.y = 0;
        controller.view.frame = frame;
    }
}

但它没有多大帮助(因为我懒得加载视图,因此在执行时不一定都会加载它们。)

有什么方法可以解决这个问题吗?

4 个答案:

答案 0 :(得分:2)

如果我理解你的问题,那么这个优秀的WWDC演示会给出了答案:https://deimos.apple.com/WebObjects/Core.woa/BrowsePrivately/adc.apple.com.4092349126.04109539109.4144345585?i=1699219987(请注意,您必须是注册的iPhone开发人员才能访问这些视频)。

顺便说一下,是否有必要为UIScrollView中的每个页面都有一个单独的UIViewController(PageViewController)?为什么不让你的MainViewController处理这个。

在Interface Builder中构建UI时,旋转设备后调整视图(以及一般用户界面)的大小要容易得多。

我再次推荐上面链接的WWDC会话,因为它对页面滚动视图以及如何处理旋转提供了很多帮助。

祝你好运!

答案 1 :(得分:2)

我使用以下方法成功实现了这一目标:

.h文件代码:

@interface ScrollViewController2 : UIViewController <UIWebViewDelegate, UIScrollViewDelegate> {
NSMutableArray *views;
int currentPage;

IBOutlet UIScrollView *scrollView;
BOOL bolPageControlUsed;
int intCurrIndex;

NSMutableArray *arrayContentData;
NSMutableArray *viewControllers;
}

@property (nonatomic, retain) IBOutlet UIScrollView *scrollView;

@property (nonatomic, retain) NSMutableArray *arrayContentData;
@property (nonatomic, retain) NSMutableArray *viewControllers;
@property (nonatomic) BOOL bolPageControlUsed;
@property (nonatomic) int intCurrIndex;

-(void)bindPages;

- (void)setUpScrollView;
- (void)alignSubviews;

- (NSURLRequest *)getPageFromDocumentsDirectory:(NSString *)pstrPageName;

-(void)initiateScrollView;
-(void)loadScrollViewWithPage:(int)page;

=============================================== =============================================

.m文件

@synthesize scrollView;

@synthesize arrayContentData,viewControllers,bolPageControlUsed,intCurrIndex;

- (void)viewDidLoad {
[super viewDidLoad];

[self bindPages];

//[self setUpScrollView];

[self initiateScrollView];
}

#pragma mark -
#pragma mark Bind Pages
-(void)bindPages{
self.arrayContentData = [[NSMutableArray alloc] init];

[self.arrayContentData addObject:@"1.html"];
[self.arrayContentData addObject:@"2.html"];
[self.arrayContentData addObject:@"3.html"];
[self.arrayContentData addObject:@"4.html"];
[self.arrayContentData addObject:@"5.html"];
[self.arrayContentData addObject:@"6.html"];

[self.arrayContentData addObject:@"1.html"];
[self.arrayContentData addObject:@"2.html"];
[self.arrayContentData addObject:@"3.html"];
[self.arrayContentData addObject:@"4.html"];
[self.arrayContentData addObject:@"5.html"];
[self.arrayContentData addObject:@"6.html"];

[self.arrayContentData addObject:@"1.html"];
[self.arrayContentData addObject:@"2.html"];
[self.arrayContentData addObject:@"3.html"];
[self.arrayContentData addObject:@"4.html"];
[self.arrayContentData addObject:@"5.html"];
[self.arrayContentData addObject:@"6.html"];

[self.arrayContentData addObject:@"1.html"];
[self.arrayContentData addObject:@"2.html"];
[self.arrayContentData addObject:@"3.html"];
[self.arrayContentData addObject:@"4.html"];
[self.arrayContentData addObject:@"5.html"];
[self.arrayContentData addObject:@"6.html"];
}

#pragma mark - 
#pragma mark Get Filename from Document Directory
- (NSURLRequest *)getPageFromDocumentsDirectory:(NSString *)pstrPageName {
NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
NSString *documentDirectory = [paths objectAtIndex:0];
NSString *yourFilePath = [NSString stringWithFormat:@"%@/Html/%@", documentDirectory, pstrPageName];
NSURL *url = [NSURL fileURLWithPath:yourFilePath];
NSURLRequest *requestObj = [NSURLRequest requestWithURL:url];
return requestObj;
}


#pragma mark -
#pragma mark ScrollView Methods
-(void)initiateScrollView{
views = [[NSMutableArray alloc] initWithCapacity:[self.arrayContentData count]];

NSMutableArray *controllers = [[NSMutableArray alloc] init];
for (unsigned i = 0; i < [self.arrayContentData count]; i++) {
    [controllers addObject:[NSNull null]];
}
self.viewControllers = controllers;
[controllers release];

scrollView.contentSize = CGSizeMake([self.arrayContentData count]*scrollView.bounds.size.width,
                                    scrollView.bounds.size.height);
scrollView.delegate = self;

if(self.intCurrIndex == 0){
    [self loadScrollViewWithPage:self.intCurrIndex];
}
}
-(void)loadScrollViewWithPage:(int)page{
if (page < 0) return;
if (page >= [self.arrayContentData count]) return;

// replace the placeholder if necessary
NSString *strContentName = [self.arrayContentData objectAtIndex:page];

//UIImageView *controller = [viewControllers objectAtIndex:page];
UIWebView *controller = [viewControllers objectAtIndex:page];

if ((NSNull *)controller == [NSNull null]) {

    UIView *v = [[UIView alloc] initWithFrame:scrollView.bounds];
    v.backgroundColor = [UIColor colorWithHue:arc4random()/(float)0x100000000
                                   saturation:0.75
                                   brightness:1.0
                                        alpha:1.0];

    controller = [[UIWebView alloc] initWithFrame:v.bounds];
    controller.delegate = self;
    controller.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
    controller.center = CGPointMake(v.bounds.size.width/2, v.bounds.size.height/2);
    [controller loadRequest:[self getPageFromDocumentsDirectory:strContentName]];
    [v addSubview:controller];
    [controller release];

    [scrollView addSubview:v];

    [views addObject:v];
    [viewControllers replaceObjectAtIndex:page withObject:controller];
    [v release];
}

[self alignSubviews];

/*
// add the controller's view to the scroll view
if (nil == controller.superview) {
    CGRect frame = scrollView.frame;
    frame.origin.x = frame.size.width * page;
    //frame.origin.y = 0;
    controller.frame = frame;
    [scrollView addSubview:controller];
}*/
}
-(void)scrollViewDidScroll:(UIScrollView *)sender{
// We don't want a "feedback loop" between the UIPageControl and the scroll delegate in
// which a scroll event generated from the user hitting the page control triggers updates from
// the delegate method. We use a boolean to disable the delegate logic when the page control is used.
if (self.bolPageControlUsed) {
    // do nothing - the scroll was initiated from the page control, not the user dragging
    return;
}
// Switch the indicator when more than 50% of the previous/next page is visible

currentPage = scrollView.contentOffset.x / scrollView.bounds.size.width;
[self loadScrollViewWithPage:currentPage];
}

//在滚动动画结束时,重置滚动源自UIPageControl时使用的布尔值      - (void)scrollViewDidEndDecelerating:(UIScrollView *)scrollView {     self.bolPageControlUsed = NO;     }

#pragma mark -
#pragma mark setUp ScrollView
- (void)setUpScrollView {
// Set up some colorful content views
views = [[NSMutableArray alloc] initWithCapacity:[self.arrayContentData count]];

for (int i = 0; i < [self.arrayContentData count]; i++) {
    UIView *v = [[UIView alloc] initWithFrame:scrollView.bounds];
    v.backgroundColor = [UIColor colorWithHue:arc4random()/(float)0x100000000
                                   saturation:0.75
                                   brightness:1.0
                                        alpha:1.0];

    NSString *strContentName = [self.arrayContentData objectAtIndex:i];

    UIWebView *controller = [[UIWebView alloc] initWithFrame:v.bounds];
    controller.delegate = self;
    controller.autoresizingMask = UIViewAutoresizingFlexibleHeight | UIViewAutoresizingFlexibleWidth;
    controller.center = CGPointMake(v.bounds.size.width/2, v.bounds.size.height/2);
    [controller loadRequest:[self getPageFromDocumentsDirectory:strContentName]];
    [v addSubview:controller];
    [controller release];

    [scrollView addSubview:v];

    [views addObject:v];
    [v release];
}

[self alignSubviews];

[scrollView flashScrollIndicators];
}

#pragma mark -
#pragma mark Align Scroll Subviews
- (void)alignSubviews {
// Position all the content views at their respective page positions
scrollView.contentSize = CGSizeMake([self.arrayContentData count]*scrollView.bounds.size.width,
                                    scrollView.bounds.size.height);

NSUInteger i = 0;
for (UIView *v in views) {
    v.frame = CGRectMake(i * scrollView.bounds.size.width, 0,
                         scrollView.bounds.size.width, scrollView.bounds.size.height);

    for (UIWebView *w in v.subviews) {
        [w setFrame:v.bounds];
    }

    i++;
}
}

#pragma mark -
#pragma mark UIWebView delegate
- (void)webViewDidStartLoad:(UIWebView *)webView {
}
- (void)webViewDidFinishLoad:(UIWebView *)webView { 
}


#pragma mark -
#pragma mark Orientation
// Override to allow orientations other than the default portrait orientation.
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
// Return YES for supported orientations
return YES;
}
- (void)willRotateToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation
                            duration:(NSTimeInterval)duration {
currentPage = scrollView.contentOffset.x / scrollView.bounds.size.width;
}
- (void)willAnimateRotationToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
                                     duration:(NSTimeInterval)duration {
[self alignSubviews];
//NSLog(@"%f", currentPage * scrollView.bounds.size.width);
scrollView.contentOffset = CGPointMake(currentPage * scrollView.bounds.size.width, 0);
}

我希望,这对所有人都有帮助。

干杯。

答案 2 :(得分:1)

我并不完全确定我理解你的权利..然而,有些想法:

框架属性是一件事(A),视图内容如何显示在另一个(B)中。框架CGRect是超视图(父视图)中视图的(理论)边界。但是,视图不一定需要填充整个框架区域

关于(A): 这里我们有UIView的autoresizingMask属性来设置调整superview时调整框架大小的方式。更改方向时会发生这种情况。但是,您通常可以依赖默认设置(目前为我工作)。

关于(B): 视图内容在视图框架中的分布方式由UIView的属性contentMode指定。使用此属性,您可以设置纵横比需要保持不变。例如,将其设置为UIViewContentModeScaleAspectFit或其他内容..

见这里: http://developer.apple.com/iphone/library/documentation/UIKit/Reference/UIView_Class/UIView/UIView.html#//apple_ref/doc/uid/TP40006816-CH3-SW99

PS:我写了“理论”,因为你的视图内容也可能超过那些框架边界 - 它们只是在UIView的clipsToBounds属性设置为YES时限制视图。我认为这是一个错误,Apple默认将此设置为NO。

答案 3 :(得分:1)

除了Efrain所写的内容之外,请注意,如果视图转换不是标识转换 - ,则视图转换后,框架属性不是有效的。

当然,您认为您的观点需要处于新的偏移位置,对吗?