1。采用第三方开源代码：iCarousel，可实现图片的多种展示效果（@"直线", @"圆圈", @"反向圆圈", @"圆桶", @"反向圆桶", @"封面展示", @"封面展示2", @"纸牌"
），另需引入<QuartzCore.framework>
2。图片的移动，拖动：UIIMageView本身不支持移动，拖动，需重写来继承UIView来实现（DragImageView）。
主要代码如下 ：
1）ImageViewController.h:
#import <UIKit/UIKit.h>
#import "iCarousel.h"
@class DragImageView;
@interface ImageViewController : UIViewController <iCarouselDataSource,iCarouselDelegate,UIActionSheetDelegate>
{
DragImageView *image;//图片视图变量，可实现缩放，拖动
}
@property (nonatomic, retain) IBOutlet iCarousel *carousel;//与界面中的子视图UIView关联(放置在主视图底部)
@property (nonatomic, retain) IBOutlet UINavigationItem *navItem;//放置在主视图顶部，上面放置一个展示效果选择按钮
- (IBAction)switchCarouselType;//切换图片列表展示效果
@end
2）ImageViewController.m:
#import "ImageViewController.h"
#import "DragImageView.h"
#define ITEM_SPACING 200
@implementation ImageViewController
@synthesize carousel;
@synthesize navItem;
//取得沙盒目录
-(NSString *)dataFilePath {
NSArray *paths =NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask, YES);
NSString *documentsDirectory = [paths objectAtIndex:0];
return documentsDirectory;
}
- (void)dealloc
{
[self.carousel release];
[self.navItem release];
[image release];
[super dealloc];
}
//初始加载- (void)viewDidLoad
{
[super viewDidLoad];
carousel.delegate = self;
carousel.dataSource = self;
carousel.type = iCarouselTypeCoverFlow;
navItem.title = @"封面展示";
UIScrollView *scrollview=[[UIScrollView alloc] initWithFrame:CGRectMake(0, 50, 768, 640)];
scrollview.pagingEnabled = YES;
DragImageView *drag=[[DragImageView alloc]initWithFrame:CGRectMake(0, 0, 768, 640)];
image=drag;
//取程序资料数据方式：【NSBundle mainBundle】
//[image setImage:[UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:[NSString stringWithFormat:@"0"] ofType:@"jpg"]]];
[image setImage:[UIImage imageWithContentsOfFile:[NSString stringWithFormat:@"%@/photo/0.jpg",[self dataFilePath]]]];
[scrollview addSubview:image];
[self.view addSubview:scrollview];
[scrollview release];
}
//切换图片展示效果
- (IBAction)switchCarouselType
{
UIActionSheet *sheet = [[UIActionSheet alloc] initWithTitle:@"选择类型" delegate:self cancelButtonTitle:nildestructiveButtonTitle:nil otherButtonTitles:@"直线", @"圆圈", @"反向圆圈", @"圆桶", @"反向圆桶", @"封面展示", @"封面展示2", @"纸牌", nil];
[sheet showInView:self.view];
[sheet release];
}
#pragma mark -
- (void)actionSheet:(UIActionSheet *)actionSheet didDismissWithButtonIndex:(NSInteger)buttonIndex
{
if (buttonIndex<0) return;
for (UIView *view in carousel.visibleItemViews)
{
view.alpha = 1.0;
}
[UIView beginAnimations:nil context:nil];
carousel.type = buttonIndex;
[UIView commitAnimations];
navItem.title = [actionSheet buttonTitleAtIndex:buttonIndex];
}
#pragma mark -
//图片列表允许显示图片的张数
- (NSUInteger)numberOfItemsInCarousel:(iCarousel *)carousel
{
return 20;
}
//图片列表加载每一个图片需调用此委托
- (UIView *)carousel:(iCarousel *)carousel viewForItemAtIndex:(NSUInteger)index
{
UILabel *lbl=[[UILabel alloc]init];
lbl.text=[NSString stringWithFormat:@"第%d张图片",index];
lbl.backgroundColor=[UIColor clearColor];
lbl.frame=CGRectMake(0, 0, 100, 30);
UIImage *imagetmp=[UIImage imageWithContentsOfFile:[NSString stringWithFormat:@"%@/photo/%d.jpg",[self dataFilePath],index]];
//UIImage *imagetmp=[UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:[NSString stringWithFormat:@"%d",index] ofType:@"jpg"]];
UIImage *imagesmall=[[UIImage alloc]init];
imagesmall=shrinkImage(imagetmp, CGSizeMake(180, 260));
UIView *view = [[UIImageView alloc] initWithImage:imagesmall];
view.frame=CGRectMake(70, 80, 180, 260);
[view addSubview:lbl];
[imagesmall release];
[lbl release];
return view;
}
//图片列表动画结束调用委托
- (void)carouselDidEndScrollingAnimation:(iCarousel *)carousels{
//此方法会将图片加载到缓存中，图片大或多时不要用，请用下面方法；
//UIImage *imagetmp=[UIImage imageNamed:@"0.jpg"];
//从沙盒目录中取图片（数据图片）
[image setImage:[UIImage imageWithContentsOfFile:[NSString stringWithFormat:@"%@/photo/%d.jpg",[selfdataFilePath],carousels.previousItemIndex]]];
//从项目目录中取图片（资源图片）
//UIImage *imagetmp=[UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:[NSString stringWithFormat:@"%d",[carousels previousItemIndex]] ofType:@"jpg"]];
//[image setImage:imagetmp];
}
//纸牌展示效果需调用此方法
- (CATransform3D)carousel:(iCarousel *)_carousel transformForItemView:(UIView *)view withOffset:(CGFloat)offset
{
view.alpha = 1.0 - fminf(fmaxf(offset, 0.0), 1.0);
CATransform3D transform = CATransform3DIdentity;
transform.m34 = self.carousel.perspective;
transform = CATransform3DRotate(transform, M_PI / 8.0, 0, 1.0, 0);
return CATransform3DTranslate(transform, 0.0, 0.0, offset * carousel.itemWidth);
}
//生成缩略图
static UIImage *shrinkImage(UIImage *original, CGSize size) {
CGFloat scale = [UIScreen mainScreen].scale;
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceRGB();
CGContextRef context = CGBitmapContextCreate(NULL, size.width * scale,
size.height * scale, 8, 0, colorSpace, kCGImageAlphaPremultipliedFirst);
CGContextDrawImage(context,
CGRectMake(0, 0, size.width * scale, size.height * scale),
original.CGImage);
CGImageRef shrunken = CGBitmapContextCreateImage(context);
UIImage *final = [UIImage imageWithCGImage:shrunken];
CGContextRelease(context);
CGImageRelease(shrunken);
return final;
}
3) DragImagView.h
#import <UIKit/UIKit.h>
@interface DragImageView : UIView
{
CGFloat lastDistance;
CGFloat imgStartWidth;
CGFloat imgStartHeight;
CGPoint beginPoint;
UIImageView *imageview;
}
-(void)setImage:(UIImage *)image;
@end
4）DragImageView.m
#import "DragImageView.h"
@implementation DragImageView
- (id)initWithFrame:(CGRect)frame
{
self = [super initWithFrame:frame];
if (self) {
// Initialization code
}
return self;
}
-(void)setImage:(UIImage *)image{
[imageview removeFromSuperview];
imageview=[[UIImageView alloc]initWithImage:image];
imageview.frame=CGRectMake(100, 0, 440, 700);
[self addSubview:imageview];
[imageview release];
imgStartWidth=imageview.frame.size.width;
imgStartHeight=imageview.frame.size.height;
}
-(void)dealloc{
[imageview release];
[super dealloc];
}
//手指事件：1个手动为拖动，2个以上手指为缩放
-(void)touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
CGPoint p1;
CGPoint p2;
CGFloat sub_x;
CGFloat sub_y;
CGFloat currentDistance;
CGRect imgFrame;
NSArray * touchesArr=[[event allTouches] allObjects];
NSLog(@"手指个数%d",[touchesArr count]);
if ([touchesArr count]>=2) {//缩放
p1=[[touchesArr objectAtIndex:0] locationInView:self];
p2=[[touchesArr objectAtIndex:1] locationInView:self];
sub_x=p1.x-p2.x;
sub_y=p1.y-p2.y;
currentDistance=sqrtf(sub_x*sub_x+sub_y*sub_y);
if (lastDistance>0) {
imgFrame=imageview.frame;
if (currentDistance>lastDistance+2) {
NSLog(@"放大");
imgFrame.size.width+=10;
if (imgFrame.size.width>1500) {
imgFrame.size.width=1500;
}
lastDistance=currentDistance;
}
if (currentDistance<lastDistance-2) {
NSLog(@"缩小");
imgFrame.size.width-=10;
if (imgFrame.size.width<50) {
imgFrame.size.width=50;
}
lastDistance=currentDistance;
}
if (lastDistance==currentDistance) {
imgFrame.size.height=imgStartHeight*imgFrame.size.width/imgStartWidth;
float addwidth=imgFrame.size.width-imageview.frame.size.width;
float addheight=imgFrame.size.height-imageview.frame.size.height;
imageview.frame=CGRectMake(imgFrame.origin.x-addwidth/2.0f, imgFrame.origin.y-addheight/2.0f, imgFrame.size.width, imgFrame.size.height);
}
}else {
lastDistance=currentDistance;
}
}
else//拖动
{
UITouch *touch = [[event touchesForView:self] anyObject];
CGPoint point = [touch locationInView:self];
imageview.center=CGPointMake(imageview.center.x+point.x-beginPoint.x, imageview.center.y+point.y-beginPoint.y);
beginPoint=point;
}
}
//手指触发开始委托事件
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event{
UITouch *touch = [[event touchesForView:self] anyObject];
beginPoint = [touch locationInView:self];
}
//手指触发结束委托事件
-(void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
lastDistance=0;
CGRect imgFrame;
imgFrame=imageview.frame;
if(imgFrame.size.width<340)//控制图片最小宽度不小于340
{
imgFrame=CGRectMake(imgFrame.origin.x-(128-imgFrame.size.width)/2.0f, imgFrame.origin.y-(180-imgFrame.size.height)/2.0f, 340,700);
}
if(imgFrame.origin.x>100)//控制左边距不大于100
{
imgFrame.origin.x=100;
}else if(imgFrame.origin.x<-100)//控制左边距不小于-100
{
imgFrame.origin.x=-100;
}
if(imgFrame.origin.y>50)//控制上边距不大于50
{
imgFrame.origin.y=50;
}else if(imgFrame.origin.y<-200) {//控制上边距不小于-200
imgFrame.origin.y=-200;
}
imageview.frame=imgFrame;
}
@end