iOS 常用技巧
1、递归查看 view 的子视图（私有方法，没有代码提示）
[self.view recursiveDescription]
2、
// 定义一个特殊字符的集合
NSCharacterSet *set = [NSCharacterSet characterSetWithCharactersInString:
@"@／：；（）¥「」＂、[]{}#%-*+=_\\|~＜＞$€^•'@#$%^&*()_+'\""];
// 过滤字符串的特殊字符
NSString *newString = [trimString stringByTrimmingCharactersInSet:set];
3、Transform 属性
//平移按钮
CGAffineTransform transForm = self.buttonView.transform;
self.buttonView.transform = CGAffineTransformTranslate(transForm, 10, 0);
//旋转按钮
CGAffineTransform transForm = self.buttonView.transform;
self.buttonView.transform = CGAffineTransformRotate(transForm, M_PI_4);
//缩放按钮
self.buttonView.transform = CGAffineTransformScale(transForm, 1.2, 1.2);
//初始化复位
self.buttonView.transform = CGAffineTransformIdentity;
4、去掉分割线多余15pt
首先在viewDidLoad方法加入以下代码：
if ([self.tableView respondsToSelector:@selector(setSeparatorInset:)]) {
[self.tableView setSeparatorInset:UIEdgeInsetsZero];
}
if ([self.tableView respondsToSelector:@selector(setLayoutMargins:)]) {
[self.tableView setLayoutMargins:UIEdgeInsetsZero];
}
然后在重写willDisplayCell方法
- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell
forRowAtIndexPath:(NSIndexPath *)indexPath{
if ([cell respondsToSelector:@selector(setSeparatorInset:)]) {
[cell setSeparatorInset:UIEdgeInsetsZero];
}
if ([cell respondsToSelector:@selector(setLayoutMargins:)]) {
[cell setLayoutMargins:UIEdgeInsetsZero];
}
}
5、计算耗时方法时间间隔
// 获取时间间隔
#define TICK CFAbsoluteTime start = CFAbsoluteTimeGetCurrent();
#define TOCK NSLog(@"Time: %f", CFAbsoluteTimeGetCurrent() - start)
6、Color颜色宏定义
// 随机颜色
#define RANDOM_COLOR [UIColor colorWithRed:arc4random_uniform(256) / 255.0 green:arc4random_uniform(256) / 255.0 blue:arc4random_uniform(256) / 255.0 alpha:1]
// 颜色(RGB)
#define RGBCOLOR(r, g, b) [UIColor colorWithRed:(r)/255.0f green:(g)/255.0f blue:(b)/255.0f alpha:1]
// 利用这种方法设置颜色和透明值，可不影响子视图背景色
#define RGBACOLOR(r, g, b, a) [UIColor colorWithRed:(r)/255.0f green:(g)/255.0f blue:(b)/255.0f alpha:(a)]
7、退出iOS应用
- (void)exitApplication {
AppDelegate *app = [UIApplication sharedApplication].delegate;
UIWindow *window = app.window;
[UIView animateWithDuration:1.0f animations:^{
window.alpha = 0;
} completion:^(BOOL finished) {
exit(0);
}];
}
8、NSArray 快速求总和 最大值 最小值 和 平均值
NSArray *array = [NSArray arrayWithObjects:@"2.0", @"2.3", @"3.0", @"4.0", @"10", nil];
CGFloat sum = [[array valueForKeyPath:@"@sum.floatValue"] floatValue];
CGFloat avg = [[array valueForKeyPath:@"@avg.floatValue"] floatValue];
CGFloat max =[[array valueForKeyPath:@"@max.floatValue"] floatValue];
CGFloat min =[[array valueForKeyPath:@"@min.floatValue"] floatValue];
NSLog(@"%f\n%f\n%f\n%f",sum,avg,max,min);
9、Debug栏打印时自动把Unicode编码转化成汉字
DXXcodeConsoleUnicodePlugin 插件
10、自动生成模型代码的插件
ESJsonFormat-for-Xcode
11、设置滑动的时候隐藏navigationbar
self.navigationController.hidesBarsOnSwipe = YES
12、隐藏导航栏上的返回字体
//Swift
UIBarButtonItem.appearance().setBackButtonTitlePositionAdjustment(UIOffsetMake(0, -60), forBarMetrics: .Default)
//OC
[[UIBarButtonItem appearance] setBackButtonTitlePositionAdjustment:UIOffsetMake(0, -60) forBarMetrics:UIBarMetricsDefault];
13、设置导航栏透明
//方法一:设置透明度
[[[self.navigationController.navigationBar subviews]objectAtIndex:0] setAlpha:0.1];
//方法二:设置背景图片
/**
* 设置导航栏,使其透明
*
*/
- (void)setNavigationBarColor:(UIColor *)color targetController:(UIViewController *)targetViewController{
//导航条的颜色 以及隐藏导航条的颜色targetViewController.navigationController.navigationBar.shadowImage = [[UIImage alloc]init];
CGRect rect=CGRectMake(0.0f, 0.0f, 1.0f, 1.0f); UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext(); CGContextSetFillColorWithColor(context, [color CGColor]); CGContextFillRect(context, rect);
UIImage *theImage = UIGraphicsGetImageFromCurrentImageContext(); UIGraphicsEndImageContext(); [targetViewController.navigationController.navigationBar setBackgroundImage:theImage forBarMetrics:UIBarMetricsDefault];
}
14、解决同时按两个按钮进两个view的问题
[button setExclusiveTouch:YES];
15、修改 textFieldplaceholder 字体颜色和大小
textField.placeholder = @"请输入手机号码";
[textField setValue:[UIColor redColor] forKeyPath:@"_placeholderLabel.textColor"];
[textField setValue:[UIFont boldSystemFontOfSize:13] forKeyPath:@"_placeholderLabel.font"];
16、UIImage 与字符串互转
//图片转字符串
-(NSString *)UIImageToBase64Str:(UIImage *) image
{
NSData *data = UIImageJPEGRepresentation(image, 1.0f);
NSString *encodedImageStr = [data base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];
return encodedImageStr;
}
//字符串转图片
-(UIImage *)Base64StrToUIImage:(NSString *)_encodedImageStr
{
NSData *_decodedImageData = [[NSData alloc] initWithBase64Encoding:_encodedImageStr];
UIImage *_decodedImage = [UIImage imageWithData:_decodedImageData];
return _decodedImage;
}
