用CollectionView画了一个课程表界面，但是在上下滑动以后前面的第几节课的标号会出现“残影”。
UICollectionViewCell *cell = [collectionView dequeueReusableCellWithReuseIdentifier:@"cell" forIndexPath:indexPath];
UILabel *classNum = [[UILabel alloc]initWithFrame:CGRectMake(0, 0, 25, CellHieght)];
if (indexPath.row == 0) {
cell.backgroundColor = [UIColor whiteColor];
classNum.text = [NSString stringWithFormat:@"%ld", indexPath.section + 1];
classNum.font = [UIFont systemFontOfSize:12];
classNum.textAlignment = NSTextAlignmentCenter;
[cell addSubview:classNum];
}
else{
cell.backgroundColor = [UIColor lightGrayColor];
}
return cell;
还请各位指教，个人感觉应该是没有reuse的问题
GitHub地址在这： https://github.com/DavidHu0921/ClassBoxForCityDLUT
问题代码在Controller/ClassCalendar/test里面
iOS 开发实用技术导航
NSHipster 中文版
› http://nshipster.cn/
cocos2d 开源 2D 游戏引擎
› http://www.cocos2d-iphone.org/
CocoaPods
› http://cocoapods.org/
Google Analytics for Mobile 统计解决方案
› http://code.google.com/mobile/analytics/
WWDC
› https://developer.apple.com/wwdc/
Design Guides and Resources
› https://developer.apple.com/design/
Transcripts of WWDC sessions
› http://asciiwwdc.com
Cocoa with Love
› http://cocoawithlove.com/
Cocoa Dev Central
› http://cocoadevcentral.com/
NSHipster
› http://nshipster.com/
Style Guides
› Google Objective-C Style Guide
› NYTimes Objective-C Style Guide
Useful Tools and Services
› Charles Web Debugging Proxy
› Smore
This topic created in 4024 days ago, the information mentioned may be changed or developed.
 |
1
DavidHu OP 唉？Markdown语法为什么不稳定啊，打了tab还是不显示成代码格式……
|
 |
3
ycge234 May 8, 2015  1
1）不使用可复用的cell
2）每次遍历cell删除所有子节点 |
 |
4
Elethom May 8, 2015 1
不想解釋，請回去看基礎部分。Reuse 機制你都不清楚。
|
 |
5
PhilCai May 8, 2015 via iPhone 1
[cell addSubview:classNum];就是这句话
|
 |
6
cheng4741 May 8, 2015 1
你这复用的什么鬼，每次复用cell都重新加个lable上来
|
 |
9
engin May 9, 2015 1
对你的label做一个标记tag，不用每次都充分添加。
``` NSInteger numberLabelTag = 1024; UILabel *classNum = (UILabel*)[cell viewWithTag:numberLabelTag]; if (indexPath.row == 0) { if (nil==classNum) { classNum = [[UILabel alloc]initWithFrame:CGRectMake(0, 0, 25, CellHieght)]; classNum.tag = numberLabelTag; [cell addSubview:classNum]; } cell.backgroundColor = [UIColor yourColor]; cell.backgroundColor = [UIColor whiteColor]; classNum.text = [NSString stringWithFormat:@"%ld", indexPath.section + 1]; classNum.font = [UIFont systemFontOfSize:12]; classNum.textAlignment = NSTextAlignmentCenter; } else{ classNum.hidden = YES; cell.backgroundColor = [UIColor lightGrayColor]; } ``` |
 |
10
newtonisaac May 10, 2015 via iPad
@engin 兄台iOS哪里学的？
|
|
11
DavidHu OP @engin 这样会造成滚动后前面的数字消失。我目前的办法是新建一个cell，然后引入，再添加到collection 里面，在else里面写一句classNum.text = nil，就没有问题了。
感谢回复 |
|
13
engin May 10, 2015
@newtonisaac 《iOS三天速成》 —_—
|
Select Language