字符串反转
//第一种:
- (NSString *)reverseWordsInString:(NSString *)str
{
NSMutableString *newString = [[NSMutableString alloc] initWithCapacity:str.length];
for (NSInteger i = str.length - 1; i >= 0 ; i --)
{
unichar ch = [str characterAtIndex:i];
[newString appendFormat:@"%c", ch];
}
return newString;
}
//第二种:
- (NSString*)reverseWordsInString:(NSString*)str
{
NSMutableString *reverString = [NSMutableString stringWithCapacity:str.length];
[str enumerateSubstringsInRange:NSMakeRange(0, str.length) options:NSStringEnumerationReverse | NSStringEnumerationByComposedCharacterSequences usingBlock:^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop) {
[reverString appendString:substring];
}];
return reverString;
}
禁止锁屏
//第一种
[UIApplication sharedApplication].idleTimerDisabled = YES;
//第二种
[[UIApplication sharedApplication] setIdleTimerDisabled:YES];
模态推出透明界面
UIViewController *vc = [[UIViewController alloc] init];
UINavigationController *na = [[UINavigationController alloc] initWithRootViewController:vc];
if ([[[UIDevice currentDevice] systemVersion] floatValue] >= 8.0)
{
na.modalPresentationStyle = UIModalPresentationOverCurrentContext;
}
else
{
self.modalPresentationStyle=UIModalPresentationCurrentContext;
}
[self presentViewController:na animated:YES completion:nil];
iOS跳转到App Store下载应用评分
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"itms-apps://itunes.apple.com/WebObjects/MZStore.woa/wa/viewContentsUserReviews?type=Purple+Software&id=APPID"]];
手动更改iOS状态栏的颜色
- (void)setStatusBarBackgroundColor:(UIColor *)color
{
UIView *statusBar = [[[UIApplication sharedApplication] valueForKey:@"statusBarWindow"] valueForKey:@"statusBar"];
if ([statusBar respondsToSelector:@selector(setBackgroundColor:)])
{
statusBar.backgroundColor = color;
}
}
判断当前ViewController是push还是present的方式显示
NSArray *viewcontrollers=self.navigationController.viewControllers;
if (viewcontrollers.count > 1)
{
if ([viewcontrollers objectAtIndex:viewcontrollers.count - 1] == self)
{
//push方式
[self.navigationController popViewControllerAnimated:YES];
}
}
else
{
//present方式
[self dismissViewControllerAnimated:YES completion:nil];
}
获取实际使用的LaunchImage图片
- (NSString *)getLaunchImageName
{
CGSize viewSize = self.window.bounds.size;
// 竖屏
NSString *viewOrientation = @"Portrait";
NSString *launchImageName = nil;
NSArray* imagesDict = [[[NSBundle mainBundle] infoDictionary] valueForKey:@"UILaunchImages"];
for (NSDictionary* dict in imagesDict)
{
CGSize imageSize = CGSizeFromString(dict[@"UILaunchImageSize"]);
if (CGSizeEqualToSize(imageSize, viewSize) && [viewOrientation isEqualToString:dict[@"UILaunchImageOrientation"]])
{
launchImageName = dict[@"UILaunchImageName"];
}
}
return launchImageName;
}










