李明的博客

Objective-C中类型转换先后顺序

使用NSThread有三种创建进程的方式:1) 创建一个新的进程，需要运行start才能启动  NSThread *newThread = [NSThread alloc]initWithTarget:<#(nonnull id)#> selector:<#(nonnull SEL)#> object:<#(nullable id)#>];例如: NSThrea...

一个View，两个背景色，交替出现：#import "ViewController.h"@interface ViewController (){ UIView *_contentView;}@end@implementation ViewController- (void)viewDidLoad { [super viewDidLoad]; _conte...

代码：#import "AnimatedViewController.h"@interface AnimatedViewController (){ UIView * _colorView;}@end@implementation AnimatedViewController- (void)viewDidLoad { [super viewDidLoad]; ...

一：新建一个项目工程并导入一些图片：二：代码：#import "ViewController.h"@interface ViewController ()@end@implementation ViewController- (void)viewDidLoad { [super viewDidLoad]; UIImageView *imageView = [[UI...

当在Objective-C项目中中使用CoreData时，由于部分数据字段默认是支持Swift的，现在要把Swift修改成Objective-C.The “Swift Language Version” (SWIFT_VERSION) build setting must be set to a supported value for targets which use Swift. This s...

OC中的Callback有四种类型：下面是第一种：NSRunloop////  BNRLogger.h//  TOCRunloopa////#import <Foundation/Foundation.h>@interface BNRLogger : NSObject@property (nonatomic) NSDate *lastTime;- (NSString *)lastTim...

#import "ViewController.h"#import <AVFoundation/AVFoundation.h>@interface ViewController (){    AVAudioPlayer * _player;    __weak IBOutlet UILabel *timeLabel;    NSTimer * _timer;}@end@implemen...

#import <Foundation/Foundation.h>int main(int argc, const char * argv[]) {    @autoreleasepool {        // insert code here...//https://www.baidu.com/img/bd_logo1.png//        NSURL *url = [NSUR...

#import <Foundation/Foundation.h>int main(int argc, const char * argv[]) {    @autoreleasepool {        // insert code here...//https://www.baidu.com/img/bd_logo1.png//        NSURL *url = [NSUR...

使用线程锁控制多线程同步进行：#import "ViewController.h"@interface ViewController ()@property (nonatomic) int leftTicketCount; //剩余票数@end@implementation ViewController- (void)viewDidLoad { [super viewDid...

开发环境: Xcode 9.2 开发语言：ObjectiveC第一步：创建一个工程，然后新建一个Property List文件.第二步： 编码如下：#import "ViewController.h"@interface ViewController ()@end@implementation ViewController- (void)viewDidLoad {    [super vi...

使用Xcode 9.2 开发语言：Objective-C测试一：1）创建一个工程。#import "ViewController.h"@interface ViewController ()@end@implementation ViewController- (void)viewDidLoad { [super viewDidLoad]; //获取沙盒目录 ...

Objective-C中的NSlog格式化字符串

实现加载图片的方式：#import "ViewController.h"@interface ViewController ()@end@implementation ViewController@synthesize tableIndexData;- (void)viewDidLoad { self.tableIndexData = [[NSArray alloc] i...

使用Alert弹窗案例：代码：#import "ViewController.h"@interface ViewController ()@property (weak, nonatomic) IBOutlet UITextField *inputName;@property (weak, nonatomic) IBOutlet UITextField *inputPassword;...

OC中的NSMutableArray的使用案例代码： #import <Foundation/Foundation.h> int main(int argc, const char * argv[]) { @autoreleasepool { NSMutableArray *arra = [[NSMutableArray al...

OC中的NSDictionary的使用例子：代码： #import <Foundation/Foundation.h> int main(int argc, const char * argv[]) { @autoreleasepool { NSArray *keys = [@"one two three four five" ...

OC中熟组的使用例子：#import <Foundation/Foundation.h>int main(int argc, const char * argv[]) { @autoreleasepool { // insert code here...// NSLog(@"Hello, World!"); NSArray *...

创建一个工程，使用两种方式来进行数据归档。@interface ViewController ()@end@implementation ViewController- (void)viewDidLoad {    [super viewDidLoad];        NSString *path = NSHomeDirectory();        NSLog(@"Path is  : %@...

代码：@implementation ViewController- (void)viewDidLoad { [super viewDidLoad]; NSArray *pathStr = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); ...

在Objective-C实现数据的持久化- (void)viewDidLoad { [super viewDidLoad]; //使用NSUserDefaults实例化一个对象 NSUserDefaults *defaultdata = [NSUserDefaults standardUserDefaults]; //存储一个键值和数据 [def...

1) 当读文件-文件不存在时：#import <Foundation/Foundation.h>int main(int argc, const char * argv[]) {    @autoreleasepool {        // insert code here...//        NSMutableString *str = [[NSMutableString st...

#import <Foundation/Foundation.h>int main(int argc, const char * argv[]) {    @autoreleasepool {        // insert code here...//        NSMutableString *str = [[NSMutableString stringWithUTF8Str...

////  Flower.h//  TOCNSDictionarya////#import <Foundation/Foundation.h>@interface Flower : NSObject@property (nonatomic) NSString *name;@property (nonatomic) int numOfslider;@end#import "Flower....

#import <Foundation/Foundation.h>int main(int argc, const char * argv[]) {    @autoreleasepool {        // insert code here...//        NSDate *now = [NSDate date];        NSDate *now = [[NSDate...

#import <Foundation/Foundation.h>int main(int argc, const char * argv[]) {    @autoreleasepool {        // insert code here...        NSDate *now = [NSDate date];        //时间指针格式        NSLog(@"...

#import <Foundation/Foundation.h>int main(int argc, const char * argv[]) {    @autoreleasepool {        // insert code here...        NSDate *now = [NSDate date];        //时间指针格式        NSLog(@"...

当用户修改MAC系统的时间时，通知程序。在.m文件中加入方法:#import "BNRLogger.h"@implementation BNRLogger- (NSString *)lastTimerString{ static NSDateFormatter *dateFormatter = nil; if(!dateFormatter) { dateFor...

#import "ViewController.h"@interface ViewController ()@end@implementation ViewController- (void)viewDidLoad {    [superviewDidLoad];    void(^printS

经三次测试DispatchQueue中的class优先级顺序是 :background default unspecified import UIKitclass ViewController: UIViewController {    override func viewDidLoad() {        s

//写文件        //        return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));        NSMutableString *mystring = [[NSMutableStringalloc] init];        NSError

#include 和#import都是先要求预处理器读取某个文件，然后将读入的内容添加至输出结果。 通常使用这两个指令来导入头文件(.h文件）。两者的差别：#import会确保预处理器只导入特定的文件一次。#include则允许多次导入同一个文件.文件名加上双引号或尖括号. 如果是双引号，那么编译器会先在项目目录下查找相应的头文件。如果是尖括号，那么编译器会先在预先设好的标准目录下

NSDateFormatter代表一个日期格式器，它的功能就是完成NSDate与NSString之间的转换。使用NSDateFormatter完成NSDate与NSString之间转换的步骤如下:1. 创建一个NSDateFormatter对象2. 调用NSDateFormatter的setDateStyle:,setTimeStyle:方法设置格式化日期，时间的风格。

#import <Foundation/Foundation.h>int main(int argc, const char * argv[]) {    @autoreleasepool {        // insert code here...//        NSLog(@"Hello, World!");        NSDate *currentTime = nil;...

#import <Foundation/Foundation.h>int main(int argc, const char * argv[]) {    @autoreleasepool {        // insert code here...        //直接赋值        NSString *myCountry = @"My Country is China"; ...

#import <Foundation/Foundation.h>int main(int argc, const char * argv[]) {    @autoreleasepool {        // insert code here...        //直接赋值        NSString *myCountry = @"My Country is China"; ...

#import <Foundation/Foundation.h>int main(int argc, const char * argv[]) {    @autoreleasepool {        // insert code here...//        NSLog(@"Hello, World!");        NSDictionary *mylist = @{@...

我们在Employee 加入类扩展。 实现属性和方法的私有化。////  BNRPerson.h//  TOCClassa//#import <Foundation/Foundation.h>@interface BNRPerson : NSObject@property (nonatomic) float heightInMeters;@property (nonatomic) in...

main.m#import <Foundation/Foundation.h>#import "Person.h"int main(int argc, const char * argv[]) { @autoreleasepool { // insert code here... NSMutableArray *stocks = [[NS...