在应用程序中，我需要显示否。滚动条中的图像（计数未知）。我将所有图像直接放在滚动条中。但是开始接收内存警告级别2.请建议我如何操作。还有其他办法吗？ 您还可以参考以下链接以更好地了解问题。
https://www.dropbox.com/sh/h0vwnhhx1acfcb5/W2TQ638udh
-(void) getPortraitScrollReady
{
UIImageView *imageView;
NSString *imageName;
int x=0;
for (NSNumber *numberObject in tagList)
{
imageName = [[NSString alloc] initWithFormat: @"%@", [self getImage:[numberObject intValue]]];
imageView = [[UIImageView alloc ] initWithFrame: CGRectMake(x, 0, 320, 320)];
imageView.image = [self thumbWithSideOfLength:320 pathForMain:imageName]; // a function that returns an image;
[scrollPortrait addSubview:imageView];
[imageName release];
[imageView release];
x+=320;
}
scrollPortrait.contentSize = CGSizeMake(x, 320);
int pageNo =[self indexofObject:imageNo inArray:tagList];
[scrollPortrait setContentOffset:CGPointMake(pageNo*320, 0) animated:NO];
}
答案 0 :(得分：2)
根据方便将所有图像保存在Array / MutableArray中。
采用Scrollview，在滚动视图中，使用5-UIImageViews显示数组中的图像。将UIScrollView的长度与5-UIImageViews匹配。
当在任何方向上完成滚动时，然后以相反的方向'释放'UIImageView＆amp;在滚动方向上“分配”一个新的UIImageVIew。
这就是我在项目中所做的。 .h文件内容
IBOutlet UIScrollView *scrlView;
UIImageView *imgView1;
UIImageView *imgView2;
UIImageView *imgView3;
UIImageView *imgView4;
UIImageView *imgView5;
NSMutableArray *imgGallery;
NSInteger mCount;
NSInteger centerImg;
CGFloat imgFrameHeight;
CGFloat imgView1X;
CGFloat imgView2X;
CGFloat imgView3X;
CGFloat imgView4X;
CGFloat imgView5X;
CGFloat previousOffsetX;
CGFloat currentOffsetX;
.m文件内容
- (void)photoGallery
{
imgGallery = [[NSMutableArray alloc] initWithCapacity:10];
[imgGallery addObject:[UIImage imageNamed:@"1.png"]];
[imgGallery addObject:[UIImage imageNamed:@"2.png"]];
[imgGallery addObject:[UIImage imageNamed:@"3.png"]];
[imgGallery addObject:[UIImage imageNamed:@"4.png"]];
[imgGallery addObject:[UIImage imageNamed:@"5.png"]];
[imgGallery addObject:[UIImage imageNamed:@"6.png"]];
[imgGallery addObject:[UIImage imageNamed:@"7.png"]];
[imgGallery addObject:[UIImage imageNamed:@"8.png"]];
[imgGallery addObject:[UIImage imageNamed:@"9.png"]];
}
- (void)photoScroller
{
CGFloat appFrameHeight = self.view.frame.size.height;
CGFloat navFrameHeight = self.navigationController.navigationBar.frame.size.height;
CGFloat tabFrameHeight = self.tabBarController.tabBar.frame.size.height;
imgFrameHeight = appFrameHeight - (navFrameHeight+tabFrameHeight);
mCount = [imgGallery count];
[scrlView setContentSize:CGSizeMake(320 * mCount, imgFrameHeight)];
CGFloat offsetX = ((320 * mCount)/2) - 160;
[scrlView setContentOffset:CGPointMake(offsetX, 0)];
imgView1 = [[UIImageView alloc] initWithFrame:CGRectMake(offsetX - (320*2), 0, 320, imgFrameHeight)];
imgView2 = [[UIImageView alloc] initWithFrame:CGRectMake(offsetX - 320, 0, 320, imgFrameHeight)];
imgView3 = [[UIImageView alloc] initWithFrame:CGRectMake(offsetX, 0, 320, imgFrameHeight)];
imgView4 = [[UIImageView alloc] initWithFrame:CGRectMake(offsetX + 320, 0, 320, imgFrameHeight)];
imgView5 = [[UIImageView alloc] initWithFrame:CGRectMake(offsetX + (320*2), 0, 320, imgFrameHeight)];
int center = mCount/2;
int tmp = center * 2;
int remainder = mCount - tmp;
if (remainder != 0) {
centerImg = center;
} else {
centerImg = center - remainder;
}
imgView1.image = [imgGallery objectAtIndex:(centerImg-2)];
imgView2.image = [imgGallery objectAtIndex:(centerImg-1)];
imgView3.image = [imgGallery objectAtIndex:centerImg];
imgView4.image = [imgGallery objectAtIndex:(centerImg+1)];
imgView5.image = [imgGallery objectAtIndex:(centerImg+2)];
[scrlView addSubview:imgView1];
[scrlView addSubview:imgView2];
[scrlView addSubview:imgView3];
[scrlView addSubview:imgView4];
[scrlView addSubview:imgView5];
}
以下是调整UIImageViews的代码
- (void)scrollViewWillBeginDragging:(UIScrollView *)scrollView
{
imgView1X = imgView1.frame.origin.x;
imgView2X = imgView2.frame.origin.x;
imgView3X = imgView3.frame.origin.x;
imgView4X = imgView4.frame.origin.x;
imgView5X = imgView5.frame.origin.x;
CGPoint previousOffset = [scrlView contentOffset];
previousOffsetX = previousOffset.x;
}
- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
//get the current offset
CGPoint currentOffset = [scrollView contentOffset];
currentOffsetX = currentOffset.x;
//NSLog(NSStringFromCGPoint(currentOffset));
//calculate offset X of RIGHT ImageView to be shifted
CGFloat identifyRightIV = previousOffsetX +640;
//calcualte new LEFT offset X for shifting the previously calcualted RIGHT ImageView
CGFloat newLX = identifyRightIV - (320*5);
//calculate offset X of LEFT ImageView to be shifted
CGFloat identifyLeftIV = previousOffsetX -640;
//calcualte new RIGHT offset X for shifting the previously calcualted LEFT ImageView
CGFloat newRX = identifyLeftIV + (320*5);
//index of new LEFT Image in an array imgGallery
int newImageL = newLX / 320;
//index of new RIGHT Image in an array imgGallery
int newImageR = newRX / 320;
//if scrolled to left
if (newLX >= 0) // Is shifting is necessary? i.e. if new LEFT offsetX is greater than lowest offsetX(0) of scrollview
{
if (currentOffsetX == (previousOffsetX-320))
{
if (imgView1X == identifyRightIV) {
imgView1.frame = CGRectMake(newLX, 0, 320, imgFrameHeight);
imgView1.image = [imgGallery objectAtIndex:newImageL];
}
else if (imgView2X == identifyRightIV) {
imgView2.frame = CGRectMake(newLX, 0, 320, imgFrameHeight);
imgView2.image = [imgGallery objectAtIndex:newImageL];
}
else if (imgView3X == identifyRightIV) {
imgView3.frame = CGRectMake(newLX, 0, 320, imgFrameHeight);
imgView3.image = [imgGallery objectAtIndex:newImageL];
}
else if (imgView4X == identifyRightIV) {
imgView4.frame = CGRectMake(newLX, 0, 320, imgFrameHeight);
imgView4.image = [imgGallery objectAtIndex:newImageL];
}
else if (imgView5X == identifyRightIV) {
imgView5.frame = CGRectMake(newLX, 0, 320, imgFrameHeight);
imgView5.image = [imgGallery objectAtIndex:newImageL];
}
}
}
//if scrolled to right
if (newRX < (mCount*320)) // Is shifting is necessary? i.e. if new RIGHT offsetX is less than highest offsetX of scrollview
{
if (currentOffsetX == (previousOffsetX+320))
{
if (imgView1X == identifyLeftIV) {
imgView1.frame = CGRectMake(newRX, 0, 320, imgFrameHeight);
imgView1.image = [imgGallery objectAtIndex:newImageR];
}
else if (imgView2X == identifyLeftIV) {
imgView2.frame = CGRectMake(newRX, 0, 320, imgFrameHeight);
imgView2.image = [imgGallery objectAtIndex:newImageR];
}
else if (imgView3X == identifyLeftIV) {
imgView3.frame = CGRectMake(newRX, 0, 320, imgFrameHeight);
imgView3.image = [imgGallery objectAtIndex:newImageR];
}
else if (imgView4X == identifyLeftIV) {
imgView4.frame = CGRectMake(newRX, 0, 320, imgFrameHeight);
imgView4.image = [imgGallery objectAtIndex:newImageR];
}
else if (imgView5X == identifyLeftIV) {
imgView5.frame = CGRectMake(newRX, 0, 320, imgFrameHeight);
imgView5.image = [imgGallery objectAtIndex:newImageR];
}
}
}
}
由于在整个生命周期中只有5-UIImageViews将在App＆amp;所有图像都是安全的阵列。
答案 1 :(得分：1)
尝试第一个问题的代码：
scrl=[[UIScrollView alloc]initWithFrame:CGRectMake(10, 92, 300, 370)];
//scrl.backgroundColor=[UIColor blackColor];
scrl.delegate=self;
scrl.showsHorizontalScrollIndicator=NO;
scrl.showsVerticalScrollIndicator=NO;
scrl.pagingEnabled=YES;
scrl.layer.cornerRadius = 5.0f;
scrl.layer.masksToBounds = YES;
scrl.layer.borderWidth = 5;
scrl.layer.borderColor = [UIColor blackColor].CGColor;
int i, x=0,y=0;
for (i=0; i<[imageName count]; i++)
{
imagBack=[[UIImageView alloc] initWithFrame:CGRectMake(x,y,300, 370)];
imagBack.image=[UIImage imageNamed:[imageName objectAtIndex:i]];
[scrl addSubview:imagBack];
x =x+300;
}
scrl.contentSize=CGSizeMake(x,370);
[self.view addSubview:scrl];
- ＆GT;第2期，你使用图片进行压缩（.png格式）图片是，试试这个：
[self imageWithImage:image CovertToSize:CGSizeMake(46, 44)];
NSData* imageData = UIImageJPEGRepresentation(image, 1.0f);//10 % quality compressed
保存图片时调用此方法：
-(UIImage *)imageWithImage:(UIImage *)image CovertToSize:(CGSize)size {
UIGraphicsBeginImageContext(size);
[image drawInRect:CGRectMake(0, 0, size.width, size.height)];
destImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return destImage;
}