iOS开发常用的代码

string = [[array valueForKey:@"description"]
componentsJoinedByString:@","];

17. TabController
随意切换
tab bar
：

[self.tabBarController setSelectedIndex:tabIndex];

或者

self.tabBarController.selectedIndex = tabIndex;

或者实现下面的
delegate
来扑捉
tab bar
的事件：

代码
-(BOOL) tabBarController:(UITabBarController *)tabBarController
shouldSelectViewController:(UIViewController *)viewController
{

if ([viewController.tabBarItem.title isEqualToString:
NSLocalizedString(@"Logout",nil)])
{

[self showLogout];

return NO;

}

return YES;}

18.
自定义
View
之间切换动画：

代码

- (void) pushController: (UIViewController*) controller

withTransition: (UIViewAnimationTransition) transition
{

[UIView beginAnimations:nil context:NULL];

[self pushViewController:controller animated:NO];

[UIView setAnimationDuration:.5];

[UIView setAnimationBeginsFromCurrentState:YES];

[UIView setAnimationTransition:transition forView:self.view cache:YES];

[UIView commitAnimations];
}

CATransition *transition = [CATransition animation];
transition.duration = kAnimationDuration;
transition.timingFunction = [CAMediaTimingFunction
functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
transition.type = kCATransitionPush;
transition.subtype = kCATransitionFromTop;
transitioning = YES;
transition.delegate = self;
[self.navigationController.view.layer addAnimation:transition forKey:nil];

self.navigationController.navigationBarHidden = NO;
[self.navigationController pushViewController:tableViewController
animated:YES];

20.
计算字符串长度：

CGFloat w = [title sizeWithFont:[UIFont fontWithName:@"Arial"
size:18]].width;

23.
在使用
UISearchBar
时，将背景色设定为
clearColor
，或者将
translucent
设
为
YES
，
都不能使背景透明，
经过一番研究，
发现了一种超级简单和实用的方法：

1

[[searchbar.subviews objectAtIndex:0]removeFromSuperview];

背景完全消除了，只剩下搜索框本身了。

24.

图像与缓存

:

UIImageView *wallpaper = [[UIImageView alloc] initWithImage:

[UIImage imageNamed:@"icon.png"]]; //
会缓存图片

UIImageView *wallpaper = [[UIImageView alloc] initWithImage:

[UIImage imageWithContentsOfFile:@"icon.png"]]; //
不会缓存图片

25. iphone-
常用的对视图图层
(layer)
的操作

对图层的操作：

(1.
给图层添加背景图片：

myView.layer.contents = (id)[UIImage
imageNamed:@"view_BG.png"].CGImage;

(2.
将图层的边框设置为圆脚

myWebView.layer.cornerRadius = 8;
myWebView.layer.masksToBounds = YES;

(3.
给图层添加一个有色边框

myWebView.layer.borderWidth = 5;
myWebView.layer.borderColor = [[UIColor colorWithRed:0.52 green:0.09
blue:0.07 alpha:1] CGColor];

将多个字符替换成空

NSCharacterSet *cs = [NSCharacterSet
characterSetWithCharactersInString:@"1234567890|"];
NSString
*resultstr
=
[[yourstr
componentsSeparatedByCharactersInSet:cs]
componentsJoinedByString:@" "];



































































































string = [[array valueForKey:@"description"]
componentsJoinedByString:@","];

17. TabController
随意切换
tab bar
：

[self.tabBarController setSelectedIndex:tabIndex];

或者

self.tabBarController.selectedIndex = tabIndex;

或者实现下面的
delegate
来扑捉
tab bar
的事件：

代码
-(BOOL) tabBarController:(UITabBarController *)tabBarController
shouldSelectViewController:(UIViewController *)viewController
{

if ([viewController.tabBarItem.title isEqualToString:
NSLocalizedString(@"Logout",nil)])
{

[self showLogout];

return NO;

}

return YES;}

18.
自定义
View
之间切换动画：

代码

- (void) pushController: (UIViewController*) controller

withTransition: (UIViewAnimationTransition) transition
{





[UIView beginAnimations:nil context:NULL];

[self pushViewController:controller animated:NO];

[UIView setAnimationDuration:.5];

[UIView setAnimationBeginsFromCurrentState:YES];

[UIView setAnimationTransition:transition forView:self.view cache:YES];

[UIView commitAnimations];
}

CATransition *transition = [CATransition animation];
transition.duration = kAnimationDuration;
transition.timingFunction = [CAMediaTimingFunction
functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
transition.type = kCATransitionPush;
transition.subtype = kCATransitionFromTop;
transitioning = YES;
transition.delegate = self;
[self.navigationController.view.layer addAnimation:transition forKey:nil];

self.navigationController.navigationBarHidden = NO;
[self.navigationController pushViewController:tableViewController
animated:YES];





20.
计算字符串长度：

CGFloat w = [title sizeWithFont:[UIFont fontWithName:@"Arial"
size:18]].width;

23.
在使用
UISearchBar
时，将背景色设定为
clearColor
，或者将
translucent
设
为
YES
，
都不能使背景透明，
经过一番研究，
发现了一种超级简单和实用的方法：

1

[[searchbar.subviews objectAtIndex:0]removeFromSuperview];

背景完全消除了，只剩下搜索框本身了。

24.

图像与缓存

:

UIImageView *wallpaper = [[UIImageView alloc] initWithImage:

[UIImage imageNamed:@"icon.png"]]; //
会缓存图片

UIImageView *wallpaper = [[UIImageView alloc] initWithImage:

[UIImage imageWithContentsOfFile:@"icon.png"]]; //
不会缓存图片





25. iphone-
常用的对视图图层
(layer)
的操作

对图层的操作：

(1.
给图层添加背景图片：

myView.layer.contents = (id)[UIImage
imageNamed:@"view_BG.png"].CGImage;

(2.
将图层的边框设置为圆脚

myWebView.layer.cornerRadius = 8;
myWebView.layer.masksToBounds = YES;

(3.
给图层添加一个有色边框

myWebView.layer.borderWidth = 5;
myWebView.layer.borderColor = [[UIColor colorWithRed:0.52 green:0.09
blue:0.07 alpha:1] CGColor];

将多个字符替换成空





NSCharacterSet *cs = [NSCharacterSet
characterSetWithCharactersInString:@"1234567890|"];
NSString
*resultstr
=
[[yourstr
componentsSeparatedByCharactersInSet:cs]
componentsJoinedByString:@" "];