个人经常用到又经常忘记的代码，记录在这里，不用一遍遍的去网上查。
UITableview
刷新
//一个section刷新
NSIndexSet *indexSet=[[NSIndexSet alloc]initWithIndex:2];
[tableview reloadSections:indexSet withRowAnimation:UITableViewRowAnimationAutomatic];
//一个cell刷新
NSIndexPath *indexPath=[NSIndexPath indexPathForRow:3 inSection:0];
[tableView reloadRowsAtIndexPaths:[NSArray arrayWithObjects:indexPath,nil] withRowAnimation:UITableViewRowAnimationNone];
滑动到某个位置
NSIndexPath *scrollIndexPath = [NSIndexPath indexPathForRow:10 inSection:0];
[[self tableView] scrollToRowAtIndexPath:scrollIndexPath atScrollPosition:UITableViewScrollPositionTop animated:YES];
UIView
移除
//移除当前视图子视图
[self.subviews makeObjectsPerformSelector:@selector(removeFromSuperview)];
坐标转换
// 将像素point由point所在视图转换到目标视图view中，返回在目标视图view中的像素值
- (CGPoint)convertPoint:(CGPoint)point toView:(UIView *)view;
// 将像素point从view中转换到当前视图中，返回在当前视图中的像素值
- (CGPoint)convertPoint:(CGPoint)point fromView:(UIView *)view;
// 将rect由rect所在视图转换到目标视图view中，返回在目标视图view中的rect
- (CGRect)convertRect:(CGRect)rect toView:(UIView *)view;
// 将rect从view中转换到当前视图中，返回在当前视图中的rect
- (CGRect)convertRect:(CGRect)rect fromView:(UIView *)view;
例把UITableViewCell中的subview(btn)的frame转换到 controllerA中
// controllerA 中有一个UITableView, UITableView里有多行UITableVieCell，cell上放有一个button
// 在controllerA中实现:
CGRect rc = [cell convertRect:cell.btn.frame toView:self.view];
或
CGRect rc = [self.view convertRect:cell.btn.frame fromView:cell];
// 此rc为btn在controllerA中的rect
或当已知btn时：
CGRect rc = [btn.superview convertRect:btn.frame toView:self.view];
或
CGRect rc = [self.view convertRect:btn.frame fromView:btn.superview];
UIScrollow
GCD
Message
//延迟函数 终止调用
[self performSelector:@selector(returnTextField1) withObject:nil afterDelay:5];
[NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(returnTextField1) object:nil];
阻止锁屏
[UIApplication sharedApplication].idleTimerDisabled = YES;
设置单个圆角
//可以分别设置四个角
UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:self.bounds
byRoundingCorners:UIRectCornerTopLeft|UIRectCornerTopRight
cornerRadii:CGSizeMake(self.frame.size.width, 30.0)];
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.frame = self.bounds;
maskLayer.path = maskPath.CGPath;
self.layer.mask = maskLayer;
UINavigationController 设置返回按钮标题
UIBarButtonItem *btnBack = [[UIBarButtonItem alloc]
initWithTitle:@"返回"
style:UIBarButtonItemStylePlain
target:self
action:nil];
self.navigationController.navigationBar.topItem.backBarButtonItem=btnBack;
