基于多年 iOS 开发经验，本文总结多条实用技能，希望对大家有所助益。
1、禁止手机睡眠
[UIApplication sharedApplication].idleTimerDisabled = YES;
2、隐藏某行cell
(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
{
// 如果是你需要隐藏的那一行，返回高度为0
if(indexPath.row == YouWantToHideRow)
return 0;
return 44;
}
// 然后再你需要隐藏cell的时候调用
[self.tableView beginUpdates];
[self.tableView endUpdates];
3、禁用button高亮
button.adjustsImageWhenHighlighted = NO;
或者在创建的时候
UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
4、tableview遇到这种报错failed to obtain a cell from its dataSource
是因为你的cell被调用的早了。先循环使用了cell，后又创建cell。顺序错了。可能原因：
xib的cell没有注册
内存中已经有这个cell的缓存了(也就是说通过你的cellId找到的cell并不是你想要的类型)，这时候需要改下cell的标识
5、cocoa pods报这个错误：unable to access 'https://github.com/facebook/pop.git/': Operation timed out after 0 milliseconds with 0 out of 0 bytes received
解决办法：原因可能是网络问题，网络请求超时了，只需要重试就行了
6、cocoa pods 出现ERROR: While executing gem ... (Errno::EPERM)
解决办法：
https://segmentfault.com/q/1010000002926243
7、动画切换window的根控制器
// options是动画选项
[UIView transitionWithView:[UIApplication sharedApplication].keyWindow duration:0.5f options:UIViewAnimationOptionTransitionCrossDissolve animations:^{
BOOL oldState = [UIView areAnimationsEnabled];
[UIView setAnimationsEnabled:NO];
[UIApplication sharedApplication].keyWindow.rootViewController = [RootViewController new];
[UIView setAnimationsEnabled:oldState];
} completion:^(BOOL finished) {
}];
8、去除数组中重复的对象
NSArray *newArr = [oldArr valueForKeyPath:@“@distinctUnionOfObjects.self"];
9、编译的时候遇到 no such file or directory: ／users／apple／XXX
是因为编译的时候，在此路径下找不到这个文件，解决这个问题，首先是是要检查缺少的文件是不是在工程中，如果不在工程中，需要从本地拖进去，如果发现已经存在工程中了，或者拖进去还是报错，这时候需要去build phases中搜索这个文件，这时候很可能会搜出现两个相同的文件，这时候，有一个路径是正确的，删除另外一个即可。如果删除了还是不行，需要把两个都删掉，然后重新往工程里拖进这个文件即可
10、iOS8系统中，tableView最好实现下-tableView: heightForRowAtIndexPath:这个代理方法，要不然在iOS8中可能就会出现显示不全或者无法响应事件的问题
11、iOS8中实现侧滑功能的时候这个方法必须实现，要不然在iOS8中无法侧滑
// 必须写的方法，和editActionsForRowAtIndexPath配对使用，里面什么不写也行
(void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {
}
12、三个通知
NSSystemTimeZoneDidChangeNotification监听修改时间界面的两个按钮状态变化
UIApplicationSignificantTimeChangeNotification 监听用户改变时间 （只要点击自动设置按钮就会调用） NSSystemClockDidChangeNotification 监听用户修改时间（时间不同才会调用）
13、SDWebImage本地缓存有时候会害人。如果之前缓存过一张图片，即使下次服务器换了这张图片，但是图片url没换，用sdwebimage下载下来的还是以前那张,所以遇到这种问题，不要先去怼服务器，清空下缓存再试就好了。
14、上线前注意：
1）、删掉代码中所有的测试代码
2）、如果后台有审核模式，提醒后台开启此模式
3）、主流程再跑一跑
4）、全局搜索waring，检查所有标记waring的地方
15、跳进app权限设置
// 跳进app设置
if (UIApplicationOpenSettingsURLString != NULL) {
NSURL *url = [NSURL URLWithString:UIApplicationOpenSettingsURLString];
[[UIApplication sharedApplication] openURL:url];
}
}
16、给一个view截图
UIGraphicsBeginImageContextWithOptions(view.bounds.size, YES, 0.0);
[view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
17、开发中如果要动态修改tableView的tableHeaderView或者tableFooterView的高度，需要给tableView重新设置，而不是直接更改高度。正确的做法是重新设置一下tableView.tableFooterView = 更改过高度的view。为什么？其实在iOS8以上直接改高度是没有问题的，在iOS8中出现了contentSize不准确的问题，这是解决办法。
18、注意对象为nil的时候，调用此对象分类的方法不会执行。
19、collectionView的内容小于其宽高的时候是不能滚动的，设置可以滚动：
collectionView.alwaysBounceHorizontal = YES;
collectionView.alwaysBounceVertical = YES;
20、设置navigationBar上的title颜色和大小
[self.navigationController.navigationBar setTitleTextAttributes:@{NSForegroundColorAttributeName : [UIColor youColor], NSFontAttributeName : [UIFont systemFontOfSize:15]}]
21、颜色转图片
(UIImage *)cl_imageWithColor:(UIColor *)color {
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 *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
22、view设置圆角
define ViewBorderRadius(View, Radius, Width, Color)\
[View.layer setCornerRadius:(Radius)];
[View.layer setMasksToBounds:YES];
[View.layer setBorderWidth:(Width)];
[View.layer setBorderColor:[Color CGColor]] // view圆角
23、强／弱引用
define WeakSelf(type) __weak typeof(type) weak##type = type; // weak
define StrongSelf(type) __strong typeof(type) type = weak##type; // strong
24、由角度转换弧度
define DegreesToRadian(x) (M_PI * (x) / 180.0)
25、由弧度转换角度
define RadianToDegrees(radian) (radian*180.0)/(M_PI)
26、获取图片资源
define GetImage(imageName) [UIImage imageNamed:[NSString stringWithFormat:@"%@",imageName]]
27、获取temp
define PathTemp NSTemporaryDirectory()
28、获取沙盒 Document
define PathDocument [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject]
29、获取沙盒 Cache
define PathCache [NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES) firstObject]
30、GCD代码只执行一次
define kDISPATCH_ONCE_BLOCK(onceBlock) static dispatch_once_t onceToken; dispatch_once(&onceToken, onceBlock);
31、自定义NSLog
ifdef DEBUG
define NSLog(fmt, ...) NSLog((@"%s [Line %d] " fmt), PRETTY_FUNCTION, LINE, ##VA_ARGS)
else
define NSLog(...)
endif
32、Font
define FontL(s) [UIFont systemFontOfSize:s weight:UIFontWeightLight]
define FontR(s) [UIFont systemFontOfSize:s weight:UIFontWeightRegular]
define FontB(s) [UIFont systemFontOfSize:s weight:UIFontWeightBold]
define FontT(s) [UIFont systemFontOfSize:s weight:UIFontWeightThin]
define Font(s) FontL(s)
33、FORMAT
define FORMAT(f, ...) [NSString stringWithFormat:f, ## VA_ARGS]
34、在主线程上运行
define kDISPATCH_MAIN_THREAD(mainQueueBlock) dispatch_async(dispatch_get_main_queue(), mainQueueBlock);
35、开启异步线程
define kDISPATCH_GLOBAL_QUEUE_DEFAULT(globalQueueBlock) dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), globalQueueBlocl);
36、通知
define NOTIF_ADD(n, f) [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(f) name:n object:nil]
define NOTIF_POST(n, o) [[NSNotificationCenter defaultCenter] postNotificationName:n object:o]
define NOTIF_REMV() [[NSNotificationCenter defaultCenter] removeObserver:self]
37、随机颜色
(UIColor *)RandomColor {
NSInteger aRedValue = arc4random() % 255;
NSInteger aGreenValue = arc4random() % 255;
NSInteger aBlueValue = arc4random() % 255;
UIColor *randColor = [UIColor colorWithRed:aRedValue / 255.0f green:aGreenValue / 255.0f blue:aBlueValue / 255.0f alpha:1.0f];
return randColor;
}
38、获取window
+(UIWindow)getWindow {
UIWindow
win = nil; //[UIApplication sharedApplication].keyWindow;
for (id item in [UIApplication sharedApplication].windows) {
if ([item class] == [UIWindow class]) {
if (!((UIWindow*)item).hidden) {
win = item;
break;
}
}
}
return win;
}
39、修改textField的placeholder的字体颜色、大小
[textField setValue:[UIColor redColor] forKeyPath:@"_placeholderLabel.textColor"];
[textField setValue:[UIFont boldSystemFontOfSize:16] forKeyPath:@"_placeholderLabel.font"];
40、统一收起键盘
[[[UIApplication sharedApplication] keyWindow] endEditing:YES];
41、控制屏幕旋转，在控制器中写
/** 是否支持自动转屏 */
(BOOL)shouldAutorotate {
return YES;
}
/** 支持哪些屏幕方向 */
(UIInterfaceOrientationMask)supportedInterfaceOrientations {
return UIInterfaceOrientationMaskLandscapeLeft | UIInterfaceOrientationMaskLandscapeRight;
}
/** 默认的屏幕方向（当前ViewController必须是通过模态出来的UIViewController（模态带导航的无效）方式展现出来的，才会调用这个方法） */
(UIInterfaceOrientation)preferredInterfaceOrientationForPresentation {
return UIInterfaceOrientationLandscapeLeft | UIInterfaceOrientationLandscapeRight;
}
42、获取app缓存大小
(CGFloat)getCachSize {
NSUInteger imageCacheSize = [[SDImageCache sharedImageCache] getSize];
//获取自定义缓存大小
//用枚举器遍历 一个文件夹的内容
//1.获取 文件夹枚举器
NSString *myCachePath = [NSHomeDirectory() stringByAppendingPathComponent:@"Library/Caches"];
NSDirectoryEnumerator *enumerator = [[NSFileManager defaultManager] enumeratorAtPath:myCachePath];
__block NSUInteger count = 0;
//2.遍历
for (NSString *fileName in enumerator) {
NSString *path = [myCachePath stringByAppendingPathComponent:fileName];
NSDictionary *fileDict = [[NSFileManager defaultManager] attributesOfItemAtPath:path error:nil];
count += fileDict.fileSize;//自定义所有缓存大小
}
// 得到是字节 转化为M
CGFloat totalSize = ((CGFloat)imageCacheSize+count)/1024/1024;
return totalSize;
}
43、清理app缓存
(void)handleClearView {
//删除两部分
//1.删除 sd 图片缓存
//先清除内存中的图片缓存
[[SDImageCache sharedImageCache] clearMemory];
//清除磁盘的缓存
[[SDImageCache sharedImageCache] clearDisk];
//2.删除自己缓存
NSString *myCachePath = [NSHomeDirectory() stringByAppendingPathComponent:@"Library/Caches"];
[[NSFileManager defaultManager] removeItemAtPath:myCachePath error:nil];
}
44、模型转字典
static NSSet *classes;
(NSMutableDictionary *)getParameterDictionary {
NSMutableDictionary *dict = [NSMutableDictionary dictionary];
Class c = self.class;
while (c) {
unsigned count;
objc_property_t *properties = class_copyPropertyList([c class], &count);
for(int i=0;i<count;i++){NSString*key=[NSStringstringWithUTF8String:property_getName(properties[i])];dict[key]=[selfvalueForKey:key];}free(properties);// 获得父类c=class_getSuperclass(c);if([selfisClassFromFoundation:c])break;
}
return dict;
}
(BOOL)isClassFromFoundation:(Class)c
{
if (c == [NSObject class] || c == [NSManagedObject class]) return YES;
__block BOOL result = NO;
[[self foundationClasses] enumerateObjectsUsingBlock:^(Class foundationClass, BOOL *stop) {
if ([c isSubclassOfClass:foundationClass]) {
result = YES;
*stop = YES;
}
}];
return result;
}
(NSSet *)foundationClasses
{
if (classes == nil) {
// 集合中没有NSObject，因为几乎所有的类都是继承自NSObject，具体是不是NSObject需要特殊判断
classes = [NSSet setWithObjects:
[NSURL class],
[NSDate class],
[NSValue class],
[NSData class],
[NSError class],
[NSArray class],
[NSDictionary class],
[NSString class],
[NSAttributedString class], nil];
}
return classes;
}
45、交换两个方法实现
Class aClass = [self class];
SEL originalSelector=@selector(viewWillAppear:);SEL swizzledSelector=@selector(xxx_viewWillAppear:);Method originalMethod=class_getInstanceMethod(aClass,originalSelector);Method swizzledMethod=class_getInstanceMethod(aClass,swizzledSelector);BOOL didAddMethod=class_addMethod(aClass,originalSelector,method_getImplementation(swizzledMethod),method_getTypeEncoding(swizzledMethod));if(didAddMethod){class_replaceMethod(aClass,swizzledSelector,method_getImplementation(originalMethod),method_getTypeEncoding(originalMethod));}else{method_exchangeImplementations(originalMethod,swizzledMethod);}
46、打印百分号和引号
NSLog(@"%%");NSLog(@"\"");
47、几个常用权限判断
if([CLLocationManager authorizationStatus]==kCLAuthorizationStatusDenied){NSLog(@"没有定位权限");}AVAuthorizationStatus statusVideo=[AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeVideo];if(statusVideo==AVAuthorizationStatusDenied){NSLog(@"没有摄像头权限");}//是否有麦克风权限AVAuthorizationStatus statusAudio=[AVCaptureDevice authorizationStatusForMediaType:AVMediaTypeAudio];if(statusAudio==AVAuthorizationStatusDenied){NSLog(@"没有录音权限");}[PHPhotoLibrary requestAuthorization:^(PHAuthorizationStatus status){if(status==PHAuthorizationStatusDenied){NSLog(@"没有相册权限");}}];
48、获取手机型号
+(NSString*)getDeviceInfo{struct utsname systemInfo;uname(&systemInfo);NSString*platform=[NSString stringWithCString:systemInfo.machine encoding:NSASCIIStringEncoding];if([platform isEqualToString:@"iPhone1,1"])return@"iPhone 2G";if([platform isEqualToString:@"iPhone1,2"])return@"iPhone 3G";if([platform isEqualToString:@"iPhone2,1"])return@"iPhone 3GS";if([platform isEqualToString:@"iPhone3,1"])return@"iPhone 4";if([platform isEqualToString:@"iPhone3,2"])return@"iPhone 4";if([platform isEqualToString:@"iPhone3,3"])return@"iPhone 4";if([platform isEqualToString:@"iPhone4,1"])return@"iPhone 4S";if([platform isEqualToString:@"iPhone5,1"])return@"iPhone 5";if([platform isEqualToString:@"iPhone5,2"])return@"iPhone 5";if([platform isEqualToString:@"iPhone5,3"])return@"iPhone 5c";if([platform isEqualToString:@"iPhone5,4"])return@"iPhone 5c";if([platform isEqualToString:@"iPhone6,1"])return@"iPhone 5s";if([platform isEqualToString:@"iPhone6,2"])return@"iPhone 5s";if([platform isEqualToString:@"iPhone7,1"])return@"iPhone 6 Plus";if([platform isEqualToString:@"iPhone7,2"])return@"iPhone 6";if([platform isEqualToString:@"iPhone8,1"])return@"iPhone 6s";if([platform isEqualToString:@"iPhone8,2"])return@"iPhone 6s Plus";// 日行两款手机型号均为日本独占，可能使用索尼FeliCa支付方案而不是苹果支付if([platform isEqualToString:@"iPhone9,1"])return@"国行、日版、港行iPhone 7";if([platform isEqualToString:@"iPhone9,2"])return@"港行、国行iPhone 7 Plus";if([platform isEqualToString:@"iPhone9,3"])return@"美版、台版iPhone 7";if([platform isEqualToString:@"iPhone9,4"])return@"美版、台版iPhone 7 Plus";if([platform isEqualToString:@"iPhone8,4"])return@"iPhone SE";if([platform isEqualToString:@"iPod1,1"])return@"iPod Touch 1G";if([platform isEqualToString:@"iPod2,1"])return@"iPod Touch 2G";if([platform isEqualToString:@"iPod3,1"])return@"iPod Touch 3G";if([platform isEqualToString:@"iPod4,1"])return@"iPod Touch 4G";if([platform isEqualToString:@"iPod5,1"])return@"iPod Touch 5G";if([platform isEqualToString:@"iPad1,1"])return@"iPad 1G";if([platform isEqualToString:@"iPad2,1"])return@"iPad 2";if([platform isEqualToString:@"iPad2,2"])return@"iPad 2";if([platform isEqualToString:@"iPad2,3"])return@"iPad 2";if([platform isEqualToString:@"iPad2,4"])return@"iPad 2";if([platform isEqualToString:@"iPad2,5"])return@"iPad Mini 1G";if([platform isEqualToString:@"iPad2,6"])return@"iPad Mini 1G";if([platform isEqualToString:@"iPad2,7"])return@"iPad Mini 1G";if([platform isEqualToString:@"iPad3,1"])return@"iPad 3";if([platform isEqualToString:@"iPad3,2"])return@"iPad 3";if([platform isEqualToString:@"iPad3,3"])return@"iPad 3";if([platform isEqualToString:@"iPad3,4"])return@"iPad 4";if([platform isEqualToString:@"iPad3,5"])return@"iPad 4";if([platform isEqualToString:@"iPad3,6"])return@"iPad 4";if([platform isEqualToString:@"iPad4,1"])return@"iPad Air";if([platform isEqualToString:@"iPad4,2"])return@"iPad Air";if([platform isEqualToString:@"iPad4,3"])return@"iPad Air";if([platform isEqualToString:@"iPad4,4"])return@"iPad Mini 2G";if([platform isEqualToString:@"iPad4,5"])return@"iPad Mini 2G";if([platform isEqualToString:@"iPad4,6"])return@"iPad Mini 2G";if([platform isEqualToString:@"i386"])return@"iPhone Simulator";if([platform isEqualToString:@"x86_64"])return@"iPhone Simulator";returnplatform;
}
49、长按复制功能
(void)viewDidLoad
{
[self.view addGestureRecognizer:[[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(pasteBoard:)]];
}
(void)pasteBoard:(UILongPressGestureRecognizer *)longPress {
if (longPress.state == UIGestureRecognizerStateBegan) {
UIPasteboard *pasteboard = [UIPasteboard generalPasteboard];
pasteboard.string = @"需要复制的文本";
}
}
50、cocoapods升级
在终端执行 sudo gem install -n / usr / local / bin cocoapods --pre
51、设置启动页后，依然显示之前的
删除app，手机重启，重新安装
52、判断图片类型
//通过图片Data数据第一个字节 来获取图片扩展名
(NSString *)contentTypeForImageData:(NSData *)data
{
uint8_t c;
[data getBytes:&c length:1];
switch (c)
{
case 0xFF:
return @"jpeg";
case0x89:return@"png";case0x47:return@"gif";case0x49:case0x4D:return@"tiff";case0x52:if([data length]<12){returnnil;}NSString*testString=[[NSString alloc]initWithData:[data subdataWithRange:NSMakeRange(0,12)]encoding:NSASCIIStringEncoding];if([testString hasPrefix:@"RIFF"]&&[testString hasSuffix:@"WEBP"]){return@"webp";}returnnil;
}
return nil;
}
53、获取手机和app信息
NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
CFShow(infoDictionary);
// app名称
NSString *app_Name = [infoDictionary objectForKey:@"CFBundleDisplayName"];
// app版本
NSString *app_Version = [infoDictionary objectForKey:@"CFBundleShortVersionString"];
// app build版本
NSString *app_build = [infoDictionary objectForKey:@"CFBundleVersion"];
//手机序列号 NSString*identifierNumber=[[UIDevice currentDevice]uniqueIdentifier];NSLog(@"手机序列号: %@",identifierNumber);//手机别名： 用户定义的名称 NSString*userPhoneName=[[UIDevice currentDevice]name];NSLog(@"手机别名: %@",userPhoneName);//设备名称 NSString*deviceName=[[UIDevice currentDevice]systemName];NSLog(@"设备名称: %@",deviceName);//手机系统版本 NSString*phoneVersion=[[UIDevice currentDevice]systemVersion];NSLog(@"手机系统版本: %@",phoneVersion);//手机型号 NSString*phoneModel=[[UIDevice currentDevice]model];NSLog(@"手机型号: %@",phoneModel);//地方型号 （国际化区域名称） NSString*localPhoneModel=[[UIDevice currentDevice]localizedModel];NSLog(@"国际化区域名称: %@",localPhoneModel);NSDictionary*infoDictionary=[[NSBundle mainBundle]infoDictionary];// 当前应用名称 NSString*appCurName=[infoDictionary objectForKey:@"CFBundleDisplayName"];NSLog(@"当前应用名称：%@",appCurName);// 当前应用软件版本 比如：1.0.1 NSString*appCurVersion=[infoDictionary objectForKey:@"CFBundleShortVersionString"];NSLog(@"当前应用软件版本:%@",appCurVersion);// 当前应用版本号码 int类型 NSString*appCurVersionNum=[infoDictionary objectForKey:@"CFBundleVersion"];NSLog(@"当前应用版本号码：%@",appCurVersionNum);
54、获取一个类的所有属性
id LenderClass = objc_getClass("Lender");
unsigned int outCount, i;
objc_property_t *properties = class_copyPropertyList(LenderClass, &outCount);
for (i = 0; i < outCount; i++) {
objc_property_t property = properties[i];
fprintf(stdout, "%s %s\n", property_getName(property), property_getAttributes(property));
}
55、image圆角
(UIImage *)circleImage
{
// NO代表透明
UIGraphicsBeginImageContextWithOptions(self.size, NO, 1);
// 获得上下文
CGContextRef ctx = UIGraphicsGetCurrentContext();
// 添加一个圆
CGRect rect = CGRectMake(0, 0, self.size.width, self.size.height);
// 方形变圆形
CGContextAddEllipseInRect(ctx, rect);
// 裁剪
CGContextClip(ctx);
// 将图片画上去
[self drawInRect:rect];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
56、image拉伸
(UIImage *)resizableImage:(NSString *)imageName
{
UIImage *image = [UIImage imageNamed:imageName];
CGFloat imageW = image.size.width;
CGFloat imageH = image.size.height;
return [image resizableImageWithCapInsets:UIEdgeInsetsMake(imageH * 0.5, imageW * 0.5, imageH * 0.5, imageW * 0.5) resizingMode:UIImageResizingModeStretch];
}
57、JSON字符串转字典
(NSDictionary *)parseJSONStringToNSDictionary:(NSString *)JSONString {
NSData *JSONData = [JSONString dataUsingEncoding:NSUTF8StringEncoding];
NSDictionary *responseJSON = [NSJSONSerialization JSONObjectWithData:JSONData options:NSJSONReadingMutableLeaves error:nil];
return responseJSON;
}
58、身份证号验证
(BOOL)validateIdentityCard {
BOOL flag;
if (self.length <= 0) {
flag = NO;
return flag;
}
NSString *regex2 = @"^(\d{14}|\d{17})(\d|[xX])$";
NSPredicate *identityCardPredicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@",regex2];
return [identityCardPredicate evaluateWithObject:self];
}
59、获取设备mac地址
(NSString *)macAddress {
int mib[6];
size_t len;
char *buf;
unsigned char *ptr;
struct if_msghdr *ifm;
struct sockaddr_dl *sdl;
mib[0] = CTL_NET;
mib[1] = AF_ROUTE;
mib[2] = 0;
mib[3] = AF_LINK;
mib[4] = NET_RT_IFLIST;
if((mib[5] = if_nametoindex("en0")) == 0) {
printf("Error: if_nametoindex error\n");
return NULL;
}
if(sysctl(mib, 6, NULL, &len, NULL, 0) < 0) {
printf("Error: sysctl, take 1\n");
return NULL;
}
if((buf = malloc(len)) == NULL) {
printf("Could not allocate memory. Rrror!\n");
return NULL;
}
if(sysctl(mib, 6, buf, &len, NULL, 0) < 0) {
printf("Error: sysctl, take 2");
return NULL;
}
ifm = (struct if_msghdr *)buf;
sdl = (struct sockaddr_dl *)(ifm + 1);
ptr = (unsigned char *)LLADDR(sdl);
NSString *outstring = [NSString stringWithFormat:@"%02X:%02X:%02X:%02X:%02X:%02X",
*ptr, *(ptr+1), *(ptr+2), *(ptr+3), *(ptr+4), *(ptr+5)];
free(buf);
return outstring;
}
60、导入自定义字体库
1、找到你想用的字体的 ttf 格式，拖入工程
2、在工程的plist中增加一行数组，“Fonts provided by application”
3、为这个key添加一个item，value为你刚才导入的ttf文件名
4、直接使用即可：label.font = [UIFont fontWithName:@"你刚才导入的ttf文件名" size:20.0]；
61、拿到当前正在显示的控制器，不管是push进去的，还是present进去的都能拿到
(UIViewController )getVisibleViewControllerFrom:(UIViewController)vc {
if ([vc isKindOfClass:[UINavigationController class]]) {
return [self getVisibleViewControllerFrom:[((UINavigationController) vc) visibleViewController]];
}else if ([vc isKindOfClass:[UITabBarController class]]){
return [self getVisibleViewControllerFrom:[((UITabBarController
) vc) selectedViewController]];
} else {
if (vc.presentedViewController) {
return [self getVisibleViewControllerFrom:vc.presentedViewController];
} else {
return vc;
}
}
}
62、runtime为一个类动态添加属性
// 动态添加属性的本质是: 让对象的某个属性与值产生关联
objc_setAssociatedObject(self, WZBPlaceholderViewKey, placeholderView, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
63、获取runtime为一个类动态添加的属性
objc_getAssociatedObject(self, WZBPlaceholderViewKey);
64、KVO监听某个对象的属性
// 添加监听者
[self addObserver:self forKeyPath:property options:NSKeyValueObservingOptionNew context:nil];
// 当监听的属性值变化的时候会来到这个方法
(void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {
if ([keyPath isEqualToString:@"property"]) {
[self textViewTextChange];
} else {
}
}
65、Reachability判断网络状态
NetworkStatus status = [[Reachability reachabilityForInternetConnection] currentReachabilityStatus];
if (status == NotReachable) {
NSLog(@"当前设备无网络");
}
if (status == ReachableViaWiFi) {
NSLog(@"当前wifi网络");
}
if (status == ReachableViaWWAN) {
NSLog(@"当前蜂窝移动网络");
}
0人点赞
作者：一个萝卜X个坑
链接：https://www.jianshu.com/p/2392e90e6cdf
来源：简书
著作权归作者所有。商业转载请联系作者获得授权，非商业转载请注明出处。
网友评论