iOS开发的小技巧

时间:2024-04-05 16:06:04

转自简书:http://www.jianshu.com/p/50b63a221f09  http://www.jianshu.com/p/08f194e9904c

原作者:叶孤城___

self.tableView.tableFooterView = [[UIView alloc] init];
试过的都说好.

加完这句之后就变成了这样.

iOS开发的小技巧

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<UIGestureRecognizerDelegate>)self;

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

self.automaticallyAdjustsScrollViewInsets = NO;

键盘事件写的好烦躁,都想摔键盘了,怎么办?

  1. 买个结实的键盘.
  2. 使用IQKeyboardManager(github上可搜索),用完之后腰也不疼了,腿也不酸了.

为什么我的app老是不流畅,到底哪里出了问题?

如图

iOS开发的小技巧

这个神器叫做:KMCGeigerCounter
快去github搬运吧.

怎么在不新建一个Cell的情况下调整separaLine的位置?

_myTableView.separatorInset = UIEdgeInsetsMake(0, 100, 0, 0);

怎么点击self.view就让键盘收起,需要添加一个tapGestures么?

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
[self.view endEditing:YES];
}

怎么给每个ViewController设定默认的背景图片?

使用基类啊,少年.

想在代码里改在xib里添加的layoutAttributes,但是怎么用代码找啊?

像拉button一样的拉你的约束.nslayoutattribute也是可以拉线的.

怎么像safari一样滑动的时候隐藏navigationbar?

navigationController.hidesBarsOnSwipe = Yes

导航条返回键带的title太讨厌了,怎么让它消失!

[[UIBarButtonItem appearance] setBackButtonTitlePositionAdjustment:UIOffsetMake(0, -60)
forBarMetrics:UIBarMetricsDefault];

CoreData用起来好烦,语法又臭又长,怎么办?

MagicalRecord

CollectionView 怎么实现tableview那种悬停的header?

CSStickyHeaderFlowLayout

文/叶孤城___(简书作者)
原文链接:http://www.jianshu.com/p/50b63a221f09
著作权归作者所有,转载请联系作者获得授权,并标注“简书作者”。

能不能只用一个pan手势来代替UISwipegesture的各个方向?

- (void)pan:(UIPanGestureRecognizer *)sender
{ typedef NS_ENUM(NSUInteger, UIPanGestureRecognizerDirection) {
UIPanGestureRecognizerDirectionUndefined,
UIPanGestureRecognizerDirectionUp,
UIPanGestureRecognizerDirectionDown,
UIPanGestureRecognizerDirectionLeft,
UIPanGestureRecognizerDirectionRight
}; static UIPanGestureRecognizerDirection direction = UIPanGestureRecognizerDirectionUndefined; switch (sender.state) { case UIGestureRecognizerStateBegan: { if (direction == UIPanGestureRecognizerDirectionUndefined) { CGPoint velocity = [sender velocityInView:recognizer.view]; BOOL isVerticalGesture = fabs(velocity.y) > fabs(velocity.x); if (isVerticalGesture) {
if (velocity.y > 0) {
direction = UIPanGestureRecognizerDirectionDown;
} else {
direction = UIPanGestureRecognizerDirectionUp;
}
} else {
if (velocity.x > 0) {
direction = UIPanGestureRecognizerDirectionRight;
} else {
direction = UIPanGestureRecognizerDirectionLeft;
}
}
} break;
} case UIGestureRecognizerStateChanged: {
switch (direction) {
case UIPanGestureRecognizerDirectionUp: {
[self handleUpwardsGesture:sender];
break;
}
case UIPanGestureRecognizerDirectionDown: {
[self handleDownwardsGesture:sender];
break;
}
case UIPanGestureRecognizerDirectionLeft: {
[self handleLeftGesture:sender];
break;
}
case UIPanGestureRecognizerDirectionRight: {
[self handleRightGesture:sender];
break;
}
default: {
break;
}
}
break;
} case UIGestureRecognizerStateEnded: {
direction = UIPanGestureRecognizerDirectionUndefined;
break;
} default:
break;
} }

拉伸图片的时候怎么才能让图片不变形?

  1. UIImage *image = [[UIImage imageNamed:@"xxx"] stretchableImageWithLeftCapWidth:10 topCapHeight:10];
    (刚才有人提醒这个已经deprecated了哈,现在的方法叫resizableImageWithCapInsets).

  2. iOS开发的小技巧

怎么播放GIF的时候这么卡,有没有好点的库?

FlipBoard出品的太适合你了。https://github.com/Flipboard/FLAnimatedImage

怎么一句话添加上拉刷新?

https://github.com/samvermette/SVPullToRefresh

[tableView addPullToRefreshWithActionHandler:^{
// prepend data to dataSource, insert cells at top of table view
// call [tableView.pullToRefreshView stopAnimating] when done
} position:SVPullToRefreshPositionBottom];

怎么把tableview里cell的小对勾的颜色改成别的颜色?

_mTableView.tintColor = [UIColor redColor];

iOS开发的小技巧

本来我的statusbar是lightcontent的,结果用UIImagePickerController会导致我的statusbar的样式变成黑色,怎么办?

- (void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated
{
[[UIApplication sharedApplication] setStatusBarStyle:UIStatusBarStyleLightContent];
}

怎么把我的navigationbar弄成透明的而不是带模糊的效果?

[self.navigationBar setBackgroundImage:[UIImage new]
forBarMetrics:UIBarMetricsDefault];
self.navigationBar.shadowImage = [UIImage new];
self.navigationBar.translucent = YES;

怎么改变uitextfield placeholder的颜色和位置?

继承uitextfield,重写这个方法
- (void) drawPlaceholderInRect:(CGRect)rect {
[[UIColor blueColor] setFill];
[self.placeholder drawInRect:rect withFont:self.font lineBreakMode:UILineBreakModeTailTruncation alignment:self.textAlignment];

文/叶孤城___(简书作者)
原文链接:http://www.jianshu.com/p/08f194e9904c
著作权归作者所有,转载请联系作者获得授权,并标注“简书作者”。