iOS开发-简单的图片查看器

现在你只要拿着手机，不管你Android还是iOS，新闻类的App不可避免都有一个功能就是图片查看，做个专题，查看一下内容，App Store中也有专门针对图片浏览的App，鉴于目前所知有限，无法做到那么高大上的App，简单的做个美女查看的Demo。没有太多的功能，上一张，下一张，标签，图片，简简单的，深刻的感觉到知识就是力量，目前知识有限的结果就是Demo简单，且学且珍惜吧。

1.新建项目(如果不会可以参考本人之前的文章)，然后在StoryBoard中进行布局,将Girl文件夹中的图片拖入项目中；

2.将UIImageView，UILabel，UIButton拖入StoryBoard中，并且设置背景图片；

设置背景图片:

3.ViewController.h中定义成员变量:

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController

@property (weak, nonatomic) IBOutlet UIImageView *imageView;

@property (weak, nonatomic) IBOutlet UILabel *pageLabel;

@end

4.上一张和下一张的事件代码:

定义一个图片数组:

@interface ViewController ()
@property NSArray *imageArr;
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
     _imageArr=@[@"girl0.jpg",@"girl1.jpg",@"girl2.jpg"];
}

上一张的代码:

//显示上一张
- (IBAction)preview:(id)sender {
    NSInteger currentIndex=[[[_pageLabel text] substringToIndex:1] integerValue];
    NSInteger allCount=[_imageArr count];

    if (currentIndex==1) {
        currentIndex=allCount;
    }else{
        currentIndex=currentIndex-1;
    }
    //设置标签
    [_pageLabel setText:[NSString stringWithFormat:@"%ld/%ld",currentIndex,(long)allCount]];
    //获取图片的名称
    NSString *imageName=[NSString stringWithFormat:@"girl%ld.jpg",(long)currentIndex-1];

    UIImage *image=[UIImage imageNamed:imageName];
    [_imageView setImage:image];

}

　下一张代码:

//显示下一张
- (IBAction)nextView:(id)sender {
    //截取标签上面的数字
    NSInteger currentIndex=[[[_pageLabel text] substringToIndex:1] integerValue];
    NSInteger allCount=[_imageArr count];
    if (currentIndex==allCount) {
        currentIndex=0;
    }
    NSString *imageName=[NSString stringWithFormat:@"girl%ld.jpg",(long)currentIndex];

    [_pageLabel setText:[NSString stringWithFormat:@"%ld/%ld",currentIndex+1,(long)allCount]];
    UIImage *image=[UIImage imageNamed:imageName];
    [_imageView setImage:image];

}

以上的代码基本上都是OC基础，UIImage设置图片的时候只需要传递一下图片名称即可，不需要传递路径；

　5.最终效果如下:

效果很简单，就是在上一张和下一张到临界点的时候判断一下，两者的代码类似，其实可以封装一下，周末愉快；

ViewController.m中的代码:

//
//  ViewController.m
//  MyPicture
//
//  Created by keso on 15/1/17.
//  Copyright (c) 2015年 keso. All rights reserved.
//

#import "ViewController.h"

@interface ViewController ()
@property NSArray *imageArr;
@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.
     _imageArr=@[@"girl0.jpg",@"girl1.jpg",@"girl2.jpg"];
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}
//显示上一张
- (IBAction)preview:(id)sender {
    NSInteger currentIndex=[[[_pageLabel text] substringToIndex:1] integerValue];
    NSInteger allCount=[_imageArr count];

    if (currentIndex==1) {
        currentIndex=allCount;
    }else{
        currentIndex=currentIndex-1;
    }
    //设置标签
    [_pageLabel setText:[NSString stringWithFormat:@"%ld/%ld",currentIndex,(long)allCount]];
    //获取图片的名称
    NSString *imageName=[NSString stringWithFormat:@"girl%ld.jpg",(long)currentIndex-1];

    UIImage *image=[UIImage imageNamed:imageName];
    [_imageView setImage:image];

}
//显示下一张
- (IBAction)nextView:(id)sender {
    //截取标签上面的数字
    NSInteger currentIndex=[[[_pageLabel text] substringToIndex:1] integerValue];
    NSInteger allCount=[_imageArr count];
    if (currentIndex==allCount) {
        currentIndex=0;
    }
    NSString *imageName=[NSString stringWithFormat:@"girl%ld.jpg",(long)currentIndex];

    [_pageLabel setText:[NSString stringWithFormat:@"%ld/%ld",currentIndex+1,(long)allCount]];
    UIImage *image=[UIImage imageNamed:imageName];
    [_imageView setImage:image];

}

@end