说明

1. PlaceHolderImageView基于SDWebImage编写

2. 给定一个图片的urlString,以及一个placeholderImage就可以优雅的显示图片加载效果

效果

源码

PlaceholderImageView.h/.m

// // PlaceholderImageView.h // SDWebImageViewPlaceHorder // // Created by YouXianMing on 16/9/14. // Copyright © 2016年 YouXianMing. All rights reserved. // #import <UIKit/UIKit.h> @interface PlaceholderImageView : UIView /** * Picture's url string. */ @property (nonatomic, strong) NSString *urlString; /** * The placeholder's image. */ @property (nonatomic, strong) UIImage *placeholderImage; /** * Default is UIViewContentModeScaleAspectFill. */ @property (nonatomic) UIViewContentMode placeholderImageContentMode; /** * Default is UIViewContentModeScaleAspectFill. */ @property (nonatomic) UIViewContentMode contentImageContentMode; @end

ImageCell.h/.m

// // ImageCell.h // SDWebImageViewPlaceHorder // // Created by YouXianMing on 16/9/14. // Copyright © 2016年 YouXianMing. All rights reserved. // #import <UIKit/UIKit.h> #import "PlaceholderImageView.h" @interface ImageCell : UITableViewCell @property (nonatomic, strong) PlaceholderImageView *placeholderImageView; @end // // ImageCell.m // SDWebImageViewPlaceHorder // // Created by YouXianMing on 16/9/14. // Copyright © 2016年 YouXianMing. All rights reserved. //

#import "ImageCell.h"

@implementation ImageCell - (instancetype)initWithStyle:(UITableViewCellStyle)style reuseIdentifier:(NSString *)reuseIdentifier { if (self = [super initWithStyle:style reuseIdentifier:reuseIdentifier]) { self.selectionStyle = UITableViewCellSelectionStyleNone; self.placeholderImageView = [[PlaceholderImageView alloc] initWithFrame:CGRectMake(0, 0, 150.f, 150.f)]; self.placeholderImageView.placeholderImage = [UIImage imageNamed:@"1"]; [self addSubview:self.placeholderImageView]; } return self; } @end

ViewController.m

// // ViewController.m // SDWebImageViewPlaceHorder // // Created by YouXianMing on 16/9/14. // Copyright © 2016年 YouXianMing. All rights reserved. // #import "ViewController.h" #import "UIImageView+WebCache.h" #import "PlaceholderImageView.h" #import "ImageCell.h" @interface ViewController () <UITableViewDelegate, UITableViewDataSource> @property (nonatomic, strong) UITableView *tableView; @property (nonatomic, strong) NSArray *pictures; @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; self.pictures = @[@"https://pic.cnblogs.com/avatar/607542/20151017230728.png", @"https://pic.cnblogs.com/face/607741/20140226202001.png", @"https://pic.cnblogs.com/face/815231/20150923160245.png", @"https://pic.cnblogs.com/face/993558/20160729092113.png", @"https://pic.cnblogs.com/face/894202/20160217151952.png", @"https://pic.cnblogs.com/face/968459/20160709111712.png", @"https://pic.cnblogs.com/face/145865/20160210174306.png", @"https://pic.cnblogs.com/face/796658/20151026090914.png", @"https://pic.cnblogs.com/face/933887/20160629214007.png", @"https://pic.cnblogs.com/face/125303/20130313094252.png", @"https://pic.cnblogs.com/face/976232/20160730173456.png", @"https://pic.cnblogs.com/face/969708/20160602120239.png", @"https://pic.cnblogs.com/face/954541/20160705113740.png", @"https://pic.cnblogs.com/face/799942/20150818204115.png"]; PlaceholderImageView *pImageView = [[PlaceholderImageView alloc] initWithFrame:CGRectMake(0, 0, 150.f, 150.f)]; [self.view addSubview:pImageView]; pImageView.urlString = @"https://pic.cnblogs.com/avatar/607542/20151017230728.png"; self.tableView = [[UITableView alloc] initWithFrame:self.view.bounds]; self.tableView.delegate = self; self.tableView.dataSource = self; self.tableView.rowHeight = 150.f; [self.view addSubview:self.tableView]; [self.tableView registerClass:[ImageCell class] forCellReuseIdentifier:@"ImageCell"]; } - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section { return _pictures.count; } - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath { ImageCell *cell = [tableView dequeueReusableCellWithIdentifier:@"ImageCell"]; cell.placeholderImageView.urlString = _pictures[indexPath.row]; return cell; } @end

以上所述是小编给大家介绍的ioS程序开发之使用PlaceholderImageView实现优雅的图片加载效果，希望对大家有所帮助，如果大家有任何疑问请给我们留言，小编会及时回复大家的。在此也非常感谢大家对查字典教程网的支持！