ios 开发常用技巧

 

1.TableView不显示没内容的Cell怎么办?

self.tableView.tableFooterView = [[UIView alloc] init];

2.自定义了leftBarbuttonItem左滑返回手势失效了怎么办?

self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc]

initWithImage:img

style:UIBarButtonItemStylePlain

target:self

action:@selector(onBack:)];

self.navigationController.interactivePopGestureRecognizer.delegate = (id)self;

（最好在父控制器里写）

3.ScrollView莫名其妙不能在viewController划到顶怎么办?

self.automaticallyAdjustsScrollViewInsets = NO;

4.键盘事件写的好烦躁,都想摔键盘了,怎么办?

使用IQKeyboardManager(github上可搜索)

5.1、禁止手机睡眠

[UIApplication sharedApplication].idleTimerDisabled = YES;

6.隐藏某行cell

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath

{

// 如果是你需要隐藏的那一行，返回高度为0

if(indexPath.row == YouWantToHideRow)

return 0;

return 44;

}// 然后再你需要隐藏cell的时候调用

[self.tableView beginUpdates];

[self.tableView endUpdates];

7.禁用button高亮

button.adjustsImageWhenHighlighted = NO;

或者在创建的时候

UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];

8.画水印

// 画水印

- (void) setImage:(UIImage *)image withWaterMark:(UIImage *)mark inRect:(CGRect)rect

{

if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 4.0)

{

UIGraphicsBeginImageContextWithOptions(self.frame.size, NO, 0.0);

}

//原图

[image drawInRect:self.bounds];

//水印图

[mark drawInRect:rect];

UIImage *newPic = UIGraphicsGetImageFromCurrentImageContext();

UIGraphicsEndImageContext();

self.image = newPic;

}

9.cell去除选中效果

cell.selectionStyle = UITableViewCellSelectionStyleNone;

10.cell点按效果

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {

[tableView deselectRowAtIndexPath:indexPath animated:YES];

}

11.更多的小技巧在www.cocoachina.com/ios/20170626/19616.html