保存並加載UIScrollView的位置

Question

我創建的應用程序使用UIScrollView滾動瀏覽圖像和加載新視圖並允許新圖層的新分層控件（像Photoshop分層一樣） - 由於某些原因，當我點擊回到圖層上，它會記住位置，但會創建一個新圖層....如何阻止這種情況發生，因此一旦選擇了圖層並選擇了一個圖像，當用戶返回它時會轉到上次加載的位置？

此外，作爲一個方面......我不能使用我的手勢識別或UIAlertView UIScrollView加載時？有誰知道爲什麼？

這裏是我的代碼....並提前:)

- layerControl:(NSInteger)index 
{ 
UIScrollView *scroll = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)]; 
scroll.pagingEnabled = YES; 
NSInteger viewCount = 15; 
for (int i = 0; i < viewCount; i++) { 
    CGFloat yOrigin = i * self.view.frame.size.width; 
    UIImageView *filterViewOverlay = [[UIImageView alloc] initWithFrame:CGRectMake(yOrigin, 0, self.view.frame.size.width, self.view.frame.size.height)]; 
    [filterViewOverlay setImage:[filterManager objectAtIndex:i]]; 
    [scroll addSubview:filterViewOverlay]; 
    [filterViewOverlay release]; 
} 
scroll.contentSize = CGSizeMake(self.view.frame.size.width * viewCount, self.view.frame.size.height); 
    [self.view addSubview:scroll]; 
[scroll release]; 

switch (index) 
{ 
    case 0: scroll = self.scroll1; 
    case 1: scroll = self.scroll2; 
    case 2: scroll = self.scroll3; 
    case 4: scroll = self.scroll4; 
    case 5: scroll = self.scroll5; 

} 

/* if (scroll == nil) 
{ 
    [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height)]; 
    scroll.pagingEnabled = YES; 
    NSInteger viewCount = 15; 
    for (int i = 0; i < viewCount; i++) { 
     CGFloat yOrigin = i * self.view.frame.size.width; 
     UIImageView *filterViewOverlay = [[UIImageView alloc] initWithFrame:CGRectMake(yOrigin, 0, self.view.frame.size.width, self.view.frame.size.height)]; 
     [filterViewOverlay setImage:[filterManager objectAtIndex:i]]; 
     [scroll addSubview:filterViewOverlay]; 
     //[filterViewOverlay release]; 
    } 
    scroll.contentSize = CGSizeMake(self.view.frame.size.width * viewCount, self.view.frame.size.height); 
    [self.view addSubview:scroll]; 
    [scroll autorelease]; */ 


} 
} 



//Method to add a filter to the page 
- (void)addFilter:(id)sender 
{ 
    UISegmentedControl *filterController = (UISegmentedControl *)sender; 

[self layerControl:[filterController selectedSegmentIndex]]; 
} 

- (UIImage*)saveImages 
{ 

UIImage *image = [UIImage imageNamed:@"UrbanPhoto##1"]; 

UIGraphicsBeginImageContext(self.view.bounds.size); 
[self.view.layer renderInContext:UIGraphicsGetCurrentContext()]; 
image = UIGraphicsGetImageFromCurrentImageContext(); 
UIGraphicsEndImageContext(); 

return image; 

} 

Answer 1

儘量節約UIScrollView.contentOffset值用戶行動前，然後在完成動作後恢復該值的感謝。