iOS－－小知识点
一. 颜色渐变
CAGradientLayer *gradientLayer = [CAGradientLayer layer];
gradientLayer.colors = @[(__bridge id)[UIColor whiteColor].CGColor, (__bridge id)[UIColor grayColor].CGColor, (__bridge id)[UIColor whiteColor].CGColor];
gradientLayer.locations = @[@0.0, @0.5, @1.0];
gradientLayer.startPoint = CGPointMake(0, 0);
gradientLayer.endPoint = CGPointMake(1.0, 0);
gradientLayer.frame = CGRectMake(0, 100, 300, 2);
[self.view.layer addSublayer:gradientLayer];
三. 使用drowRect绘制简单图形
//获取上下文 CGContextRef
context=UIGraphicsGetCurrentContext(); //设置绘制地区的颜色
CGContextSetRGBFillColor(context, 1, 0, 0, 1); //设置绘制的位置和大小
CGContextFillRect(context, CGRectMake(0, 100, 100, 100));
NSString * text=@"文字";
UIFont * font=[UIFont systemFontOfSize:14];
[text drawAtPoint:CGPointMake(0, 200) withAttributes:font.fontDescriptor.fontAttributes];
UIImage *img=[UIImage imageNamed:@""];
[img drawInRect:CGRectMake(0, 300, 100, 100)];
四. 可变数组与不可变数组之间的转换
NSMutableArray * mutablearray=[[NSMutableArray alloc]initWithCapacity:0];
NSArray *copyarray=[mutablearray copy];
copyarray=@[@"1",@"2",@"3"];
NSArray *array = [[NSArray alloc]init];
NSMutableArray *copymutablearray=[array mutableCopy];
[copymutablearraysetObject:@"加入到第一位"atIndexedSubscript:0];
[copymutablearray addObject:@"排序加入"];
[copymutablearray addObjectsFromArray:copyarray];
五. 快速求和，最大值，最小值，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];
六. 对控件的旋转，平移，缩放，复位
//平移
CGAffineTransform transForm = _pingyibu.transform;
_pingyibu.transform=CGAffineTransformTranslate(transForm, 100, 0);
//旋转
_pingyibu.transform = CGAffineTransformRotate(transForm, M_PI_4);
//缩放按钮
_pingyibu.transform = CGAffineTransformScale(transForm, 1.2, 1.2);
//初始化复位
_pingyibu.transform = CGAffineTransformIdentity;
七. 设置label的行间距
NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:_xuanzhuanla.text];
NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
[paragraphStylesetLineSpacing:3]; //调整行间距
[attributedString addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0,[_xuanzhuanla.text length])];
_xuanzhuanla.attributedText = attributedString;
八. 让应用直接闪退
AppDelegate *app = [UIApplication sharedApplication].delegate;
UIWindow *window = app.window;
[UIView animateWithDuration:1.0f animations:^{
window.alpha = 0;
} completion:^(BOOL finished) {
exit(0);
}];
九. 手机震动
AudioServicesPlaySystemSound(kSystemSoundID_Vibrate);
十一. label自适应高度
CGRect rect = [la.text boundingRectWithSize:CGSizeMake(WIDTH-70, MAXFLOAT) options:NSStringDrawingUsesLineFragmentOrigin|NSStringDrawingUsesFontLeading attributes:@{NSFontAttributeName:la.font} context:nil];
十三. image转换成data类型
NSData *data=UIImagePNGRepresentation(image);
NSData *data=UIImageJPEGRepresentation(image, 1.0);
十四. 获取当前时间和时间戳
//当前时间NSDate *senddate=[NSDate date];
NSDateFormatter *dateformatter=[[NSDateFormatter alloc] init];
[dateformattersetDateFormat:@"YYYY-MM-dd HH:mm:ss"];
NSString *locationString=[dateformatter stringFromDate:senddate];
//当前时间戳
NSDate* dat = [NSDate dateWithTimeIntervalSinceNow:0];
NSTimeInterval a=[dat timeIntervalSince1970];
NSString *timeString = [NSString stringWithFormat:@"%f", a];
long s = [timeString intValue];
十五. 对比时间差
-(int)max:(NSDate *)datatime {
//创建日期格式化对象
NSDateFormatter *dateFormatter=[[NSDateFormatter alloc] init];
[dateFormattersetDateFormat:@"YYYY-MM-dd hh:mm:ss"];
NSDate *senddate=[NSDate date];
NSString *locationString=[dateFormatter stringFromDate:senddate];
NSDate *date=[dateFormatter dateFromString:locationString];
//取两个日期对象的时间间隔：
//这里的NSTimeInterval 并不是对象，是基本型，其实是double类型，是由c定义的:typedef double NSTimeInterval;
NSTimeInterval time=[date timeIntervalSinceDate:datatime];
int days=((int)time)/(3600*24);
return days;
}
十六. 使提示框消失（定时）
[alu dismissWithClickedButtonIndex:0 animated:NO];
十七. 设置self.title的颜色
UIColor *color = [UIColor whiteColor];
NSDictionary * dict=[NSDictionary dictionaryWithObject:colorforKey:UITextAttributeTextColor];
self.navigationController.navigationBar.titleTextAttributes = dict;
十八. 请求定位权限以及定位属性
//定位管理器
_locationManager = [[CLLocationManager alloc]init];
//如果没有授权则请求用户授权
if([CLLocationManager authorizationStatus]==kCLAuthorizationStatusNotDetermined){
[_locationManager requestWhenInUseAuthorization];
} else if([CLLocationManager authorizationStatus]==kCLAuthorizationStatusAuthorizedWhenInUse){
//设置代理
_locationManager.delegate=self;
//设置定位精度
_locationManager.desiredAccuracy = kCLLocationAccuracyBest;
//定位频率,每隔多少米定位一次
CLLocationDistance distance=10.0;
_locationManager.distanceFilter = distance;
//启动跟踪定位
[_locationManager startUpdatingLocation];
}
十九. 通过经纬度计算距离
BOOL JuLi = NO;
CLLocation *orig = [[CLLocation alloc] initWithLatitude:oldlat longitude:oldlong];
CLLocation* dist = [[CLLocation alloc] initWithLatitude:nowlat longitude:nowlong];
CLLocationDistance kilometers = [orig distanceFromLocation:dist];
NSLog(@"距离:%f",kilometers);
if(kilometers >= 10) {
JuLi=YES;
}else{
JuLi=NO;
}
return JuLi;
二十. 弹出效果
/** 弹出对话框的动画 动画时长
@param changeOutView
@param dur
/*
-(void)exChangeOut:(UIView *)changeOutView dur:(CFTimeInterval)dur{
CAKeyframeAnimation *animation;
animation = [CAKeyframeAnimation animationWithKeyPath:@"transform"];
animation.duration = dur;
animation.delegate = self;
animation.removedOnCompletion = NO;
animation.fillMode = kCAFillModeForwards;
NSMutableArray *values = [NSMutableArray array];
[values addObject:[NSValue valueWithCATransform3D:CATransform3DMakeScale(0.1, 0.1, 1.0)]];
[values addObject:[NSValue valueWithCATransform3D:CATransform3DMakeScale(1.2, 1.2, 1.0)]];
[values addObject:[NSValue valueWithCATransform3D:CATransform3DMakeScale(0.9, 0.9, 0.9)]];
[values addObject:[NSValue valueWithCATransform3D:CATransform3DMakeScale(1.0, 1.0, 1.0)]];
animation.values = values;
animation.timingFunction = [CAMediaTimingFunctionfunctionWithName: @"easeInEaseOut"]; [changeOutView.layer addAnimation:animationforKey:nil];
}
二十一. 设置TextField左右视图
-(id)initWithFrame:(CGRect)frame drawingLeft:(UIImageView *)icon drawingRight:(UIButton *)bu{
self = [super initWithFrame:frame];
if(self) {
self.leftView = icon;
self.leftViewMode = UITextFieldViewModeAlways;
self.rightView= bu;
self.rightViewMode=UITextFieldViewModeAlways;
}
return self;
}
-(CGRect)leftViewRectForBounds:(CGRect)bounds{
CGRect iconRect = [super leftViewRectForBounds:bounds];
iconRect.origin.x += 5;
return iconRect;
}
-(CGRect)rightViewRectForBounds:(CGRect)bounds{
CGRect burect = [super rightViewRectForBounds:bounds];
burect.origin.x +=-10;
return burect;
}
二十二. 常用宏定义
#define PUSH(x) AppDelegate *appdelegate=(AppDelegate *)[UIApplication sharedApplication].delegate;[(UINavigationController*)appdelegate.window.rootViewController pushViewController:x animated:YES];
#define POP AppDelegate *appdelegate=(AppDelegate *)[UIApplication sharedApplication].delegate;[(UINavigationController*)appdelegate.window.rootViewController popViewControllerAnimated:YES];
#define POPROOT OGPAppDelegate *appdelegate=(OGPAppDelegate *)[UIApplication sharedApplication].delegate;[(UINavigationController*)appdelegate.window.rootViewController popToRootViewControllerAnimated:YES];
#define IOS7 ([[UIDevice currentDevice].systemVersion floatValue] >= 7.0f)#define IPHONE_4INCH ([UIScreen mainScreen].bounds.size.height > 480.0f)
#define RANDOM_COLOR [UIColor colorWithRed:arc4random_uniform(256) / 255.0 green:arc4random_uniform(256) / 255.0 blue:arc4random_uniform(256) / 255.0 alpha:1]
二十三. 获取版本号提示版本更新
-(void)VersionButton{
NSString * string=[NSString stringWithContentsOfURL:[NSURL URLWithString:@"http://itunes.apple.com/lookup?id=??????????"] encoding:NSUTF8StringEncoding error:nil];
if(string!=nil && [string length] > 0 && [string rangeOfString:@"version"].length==7) {
[self checkenAppUpdate:string];
}
}
-(void)checkenAppUpdate:(NSString *)appinfo{
NSString *version=[[[NSBundle mainBundle] infoDictionary] objectForKey:@"CFBundleVersion"];
NSString *appInfo1=[appinfo substringFromIndex:[appinfo rangeOfString:@"\"version\":"].location+10];
appInfo1 = [[appInfo1 substringToIndex:[appInfo1 rangeOfString:@","].location] stringByReplacingOccurrencesOfString:@"\""withString:@""];
if(![appInfo1 isEqualToString:version]) {
UIAlertView * alert=[[UIAlertView alloc]initWithTitle:@"" message [NSString stringWithFormat:@"新版本%@, 已经发布",appInfo1] delegate:self cancelButtonTitle:@"知道了"otherButtonTitles: nil];
alert.delegate=self;
[alert addButtonWithTitle:@"前往更新"];
[alert show];
alert.tag=20;
}
}
-(void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex {
if(buttonIndex==1 & alertView.tag==20) {
NSString *url=@"https://appsto.re/cn/-naScb.i";
[[UIApplication sharedApplication] openURL:[NSURL URLWithString:url]];
}
}
二十四. 获取设备或APP信息
//返回应用程序名称
+(NSString *) getAppName{ NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
return[infoDictionary objectForKey:@"CFBundleDisplayName"];
}
//返回应用版本号+(NSString *) getAppVersion{ NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
return[infoDictionary objectForKey:@"CFBundleShortVersionString"];
}
+(NSString *) getAppBundleVersion{
NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
return [infoDictionary objectForKey:@"CFBundleVersion"];
}
//设备型号
+(NSString *) getSystemName{
return [[UIDevice currentDevice] systemName];
}
//设备版本号
+(NSString *) getSystemVersion{
return[[UIDevice currentDevice] systemVersion];
}
二十五. 内存泄漏分析
静态分析内存泄露 使用Xcode自带的Analyze功能
（Product-> Analyze）（Shift + Command + B），对代码进行静态分析，
对于内存泄露（Potential Memory Leak）, 未使用局部变量(dead store)，
逻辑错误(Logic Flaws)以及API使用问题(API-usage)等明确的展示出来。
静态分析的内存泄露情况比较简单，开发者都能很快的解决。这里不做赘述。
动态分析内存泄露 使用Xcode自带的Profile功能
（Product-> Profile）（Command + i）弹出工具框，
选择Leaks打开，选择运行设备点左上角的Record录制按钮，
项目就会在已选好的设备上运行，并开始录制内存检测情况。
选Leaks查看泄露情况，在Leaks的详细菜单Details选项里选调用树Call Tree，
可查看所有内存泄露发生在哪些地方。
再在右侧的齿轮设置-Call Tree-勾选Hide System Libraries，
则可直接看内存泄露发生的函数名、方法名。
点击函数名、方法名，可直接跳到函数方法的细节，
可以看到哪一句代码出现了内存泄露，以及泄露了多少内存。
接下来就要回到Xcode，找到出现内存泄露的函数方法，仔细分析如何出现的内存泄露;
一般使用ARC，按照上面一提到的内存理解和编码习惯是不会出现内存泄露的。
但我们在开发过程中，经常要使用第三方的一些类库，特别是涉及到加密的类库，
用c或c++来编码的加密解密方法，会出现内存泄露。
此时，我们要明白这些内存分配，需要手动释放。
要一步一步看，哪里分配了内存，在使用完之后一定要记得释放free它。
二十六. block循环利用导致内存泄漏
A *a = [[A alloc] init];
a.finishBlock = ^(NSDictionary paraments){
[adoSomething];
};
//对于这种在block块里引用对象a的情况，要在创建对象a时加修饰符block来防止循环引用。
block A *a = [[A alloc] init];
a.finishBlock = ^(NSDictionary paraments){
[a doSomething];
};
//或
A __block a = [[A alloc] init];
a.finishBlock = ^(NSDictionary paraments){
[a doSomething];
};
//或者，需要在block中调用用self的方法、属性、变量时，可以这样写
__weak typeof(self) weakSelf = self;
//在block中使用weakSelf。
__weak typeof(self) weakSelf = self;
[bdoSomethingWithFinishBlock:^{
weakSelf.text = @"内存检测";
[weakSelfdoSomething];
}];
二十七. label 的空格属性和局部字段颜色
//设置 label 的 autoresizingMask 为 NO ,可以使用空格间隔字符串!
NSMutableAttributedString *hintString=[[NSMutableAttributedString alloc]initWithString:@"点击注册按钮服务协议"];
//获取要调整颜色的文字位置,调整颜色
NSRange range1=[[hintString string]rangeOfString:@"注册"];
[hintString addAttribute:NSForegroundColorAttributeName value:[UIColor greenColor] range:range1];
NSRange range2=[[hintString string]rangeOfString:@"服务协议"];
[hintString addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:range2];
hintLabel.attributedText=hintString;
二十八. 过滤特殊字符
// 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];
二十九. 设置滑动的时候隐藏 navigationbar
//第1种:
navigationController.hidesBarsOnSwipe = Yes
//第2种: 当我们的手离开屏幕时候隐藏
- (void)scrollViewWillEndDragging:(UIScrollView *)scrollView withVelocity:(CGPoint)velocity targetContentOffset:(inout CGPoint *)targetContentOffset {
if(velocity.y > 0){
[self.navigationControllersetNavigationBarHidden:YES animated:YES];
} else {
[self.navigationControllersetNavigationBarHidden:NO animated:YES];
}
}
//velocity.y这个量，在上滑和下滑时，变化极小（小数），但是因为方向不同，有正负之分，这就很好处理了。
三十. 屏幕截图
// 1. 开启一个与图片相关的图形上下文
UIGraphicsBeginImageContextWithOptions(self.view.bounds.size,NO,0.0);
// 2. 获取当前图形上下文
CGContextRef ctx = UIGraphicsGetCurrentContext();=
// 3. 获取需要截取的view的layer
[self.view.layer renderInContext:ctx];
// 4. 从当前上下文中获取图片
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
// 5. 关闭图形上下文
UIGraphicsEndImageContext();
// 6. 把图片保存到相册
UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);
三十一. 去掉 tabbar 和 navgationbar 的黑线
//去掉tabBar顶部线条
CGRect rect = CGRectMake(0, 0, 1, 1); UIGraphicsBeginImageContext(rect.size);
CGContextRef context = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, [[UIColor clearColor] CGColor]);
CGContextFillRect(context, rect);
UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
[self.tabBarsetBackgroundImage:img];
[self.tabBarsetShadowImage:img];
//[self.navigationController.navigationBarsetBackgroundImage:img];
//self.navigationController.navigationBar.shadowImage = ima;
self.tabBar.backgroundColor = SLIVERYCOLOR;
三十二. 判断字符串中是否含有中文
-(BOOL)isChinese:(NSString *)str{
NSString *match=@"(^[\u4e00-\u9fa5]+$)";
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"SELF matches %@", match];
return [predicate evaluateWithObject:str];
}
三十三. 解决父视图和子视图的手势冲突问题
/** 解决手势冲突 */
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
if([touch.view isDescendantOfView:cicView]) {
returnNO;
}
returnYES;
}
三十四. 获取当前连接的Wi-Fi的名称
NSString *wifiName = @"Not Found";
CFArrayRef myArray = CNCopySupportedInterfaces();
if(myArray != nil) {
CFDictionaryRef myDict = CNCopyCurrentNetworkInfo(CFArrayGetValueAtIndex(myArray, 0));
if(myDict != nil) {
NSDictionary *dict = (NSDictionary*)CFBridgingRelease(myDict);
wifiName = [dict valueForKey:@"SSID"];
}
}
三十五. 跨控制器跳转返回
for(UIViewController *controllerinself.navigationController.viewControllers) {
if([controller isKindOfClass:[@“你要返回的控制器类名” class]])
{
[self.navigationController popToViewController:controller animated:YES];
}
}
三十六. layer.cornerRadius 圆角流畅性的优化
loginBtn.layer.rasterizationScale = [UIScreen mainScreen].scale;
三十七. 导航栏和下方视图间隔距离消失
self.automaticallyAdjustsScrollViewInsets=YES;
三十八. 毛玻璃效果(ios8.0以后的版本)
UIVisualEffectView *visualEffectView = [[UIVisualEffectView alloc] initWithEffect:[UIBlurEffect effectWithStyle:UIBlurEffectStyleLight]];
visualEffectView.frame = CGRectMake(0, 0, 320*[FlexibleFrame ratio], 180*[FlexibleFrame ratio]);
visualEffectView.alpha = 1.0;
三十九. 移动工程不需要配置路径
创建.pch文件时 , BuildSetting 中的 Prefix Header 中的路径开头可以写 $(SRCROOT)/工程地址,
这样写的好处可以使你的挪动代码不用手动更换路径!
四十. 判断两个数组是否相同
NSArray *array1 = [NSArray arrayWithObjects:@"a", @"b", @"c", nil];
NSArray *array2 = [NSArray arrayWithObjects:@"d", @"a", @"c", nil];
bool bol =false;
//创建俩新的数组
NSMutableArray *oldArr = [NSMutableArray arrayWithArray:array1];
NSMutableArray *newArr = [NSMutableArray arrayWithArray:array2];
//对数组1排序
[oldArr sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {
return obj1 > obj2;
}];
//对数组2排序
[newArr sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {
return obj1 > obj2;
}];
if(newArr.count == oldArr.count) {
bol =true;
for(int16_t i = 0; i < oldArr.count; i++) {
id c1 = [oldArr objectAtIndex:i];
id newc = [newArr objectAtIndex:i];
if(![newc isEqualToString:c1]) {
bol =false;break;
}
}
}
if(bol) {
NSLog(@" ------------- 两个数组的内容相同！");
}else{
NSLog(@"-=-------------两个数组的内容不相同！");
}
四十一. block
对于block，都应该使用copy来声明，
原因是block来捕获上下文的信息
[官方文档]
https://link.juejin.im/?target=https%3A%2F%2Fdeveloper.apple.com%2Flibrary%2Fios%2Fdocumentation%2FCocoa%2FConceptual%2FProgrammingWithObjectiveC%2FWorkingwithBlocks%2FWorkingwithBlocks.html%23%2F%2Fapple_ref%2Fdoc%2Fuid%2FTP40011210-CH8-SW12
四十三. 计算一段NSString在视图中渲染出来的尺寸
+ (CGSize)sizeOfString:(NSString *)textString font:(UIFont *)font bound:(CGSize)bound {
NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
paragraphStyle.lineBreakMode = NSLineBreakByWordWrapping;
paragraphStyle.alignment = NSTextAlignmentLeft;
if(font == nil) {
font = [UIFont systemFontOfSize:[UIFont systemFontSize]]; }
NSDictionary * attributes = @{NSFontAttributeName : font, NSParagraphStyleAttributeName : paragraphStyle};
NSAttributedString* attributedString = [[NSAttributedString alloc] initWithString:textString attributes:attributes];
return [TTTAttributedLabel sizeThatFitsAttributedString:attributedString withConstraints:CGSizeMake(bound.width, 999) limitedToNumberOfLines:0];
}
四十四. 获取相应的字体类型名
for(NSString *fontfamilynamein[UIFont familyNames]) {
NSLog(@"Family:'%@'",fontfamilyname);
for(NSString *fontName in [UIFont fontNamesForFamilyName:fontfamilyname]) {
NSLog(@"\tfont:'%@'",fontName);
}
NSLog(@"~~~~~~~~");
}
四十五. Masonry和SVProgreaaHUD需要注意
使用Masonry约束TTTAttributedLabel的时候，
初始化TTTAttributedLabel需要设置frame为CGRectZero，
否则约束会不生效。
SVProgressHUD如果要自定义一些属性，
比如loading状态转圈的颜色，
必须先设置style为SVProgressHUDStyleCustom，
这样自定义的状态才会生效。
四十六. 打印View所有子视图
po [[self view]recursiveDescription]
四十七. layoutSubviews调用的调用时机
* 当视图第一次显示的时候会被调用
* 当这个视图显示到屏幕上了,点击按钮
* 添加子视图也会调用这个方法
* 当本视图的大小发生改变的时候是会调用的
* 当子视图的frame发生改变的时候是会调用的
* 当删除子视图的时候是会调用的
四十八. UIImageView填充模式
@"UIViewContentModeScaleToFill", // 拉伸自适应填满整个视图
@"UIViewContentModeScaleAspectFit", // 自适应比例大小显示
@"UIViewContentModeScaleAspectFill", // 原始大小显示
@"UIViewContentModeRedraw", // 尺寸改变时重绘
@"UIViewContentModeCenter", // 中间
@"UIViewContentModeTop", // 顶部
@"UIViewContentModeBottom", // 底部
@"UIViewContentModeLeft", // 中间贴左
@"UIViewContentModeRight", // 中间贴右
@"UIViewContentModeTopLeft", // 贴左上
@"UIViewContentModeTopRight", // 贴右上
@"UIViewContentModeBottomLeft", // 贴左下
@"UIViewContentModeBottomRight", // 贴右下
四十九. MRC和ARC混编设置方式
在XCode中targets的build phases选项下Compile Sources下选择 不需要arc编译的文件
双击输入 -fno-objc-arc 即可
MRC工程中也可以使用ARC的类，
方法如下：
在XCode中targets的build phases选项下Compile Sources下选择要使用arc编译的文件
双击输入 -fobjc-arc 即可
五十. 解决tableview的分割线短一截
-(void)viewDidLayoutSubviews {
if([self.tableView respondsToSelector:@selector(setSeparatorInset:)]) {
[self.tableViewsetSeparatorInset:UIEdgeInsetsMake(0,0,0,0)];
} if ([self.tableView respondsToSelector:@selector(setLayoutMargins:)]) {
[self.tableViewsetLayoutMargins:UIEdgeInsetsMake(0,0,0,0)];
}
}
-(void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cellforRowAtIndexPath:(NSIndexPath *)indexPath {
if([cell respondsToSelector:@selector(setSeparatorInset:)]) {
[cellsetSeparatorInset:UIEdgeInsetsZero];
} if ([cell respondsToSelector:@selector(setLayoutMargins:)]){
[cellsetLayoutMargins:UIEdgeInsetsZero];
}
}
五十一. 修改textFieldplaceholder字体颜色和大小
textField.placeholder = @"username is in here!";
[textFieldsetValue:[UIColor redColor]forKeyPath:@"_placeholderLabel.textColor"];
[textFieldsetValue:[UIFont boldSystemFontOfSize:16]forKeyPath:@"_placeholderLabel.font"];
五十二. 修改状态栏字体颜色
//只能设置两种颜色，黑色和白色，系统默认黑色
//设置为白色方法：
（1）在plist里面添加Status bar style，值为UIStatusBarStyleLightContent（白色）或UIStatusBarStyleDefault（黑 色）
（2）在Info.plist中设置UIViewControllerBasedStatusBarAppearance 为NO
五十三.调用相机后状态栏消失
[[UIApplication sharedApplication]setStatusBarHidden:NO animated:NO];
[[UIApplication sharedApplication]setStatusBarStyle:UIStatusBarStyleBlackTranslucent animated:YES];
五十四. 修改UIAlertController字体颜色
//修改title
NSMutableAttributedString *alertControllerStr = [[NSMutableAttributedString alloc] initWithString:@"提示"];
[alertControllerStr addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:NSMakeRange(0, 2)];
[alertControllerStr addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:17] range:NSMakeRange(0, 2)];
if(alertController valueForKey:@"attributedTitle") {
[alertControllersetValue:alertControllerStrforKey:@"attributedTitle"];
}
//修改message
NSMutableAttributedString *alertControllerMessageStr = [[NSMutableAttributedString alloc] initWithString:@"提示内容"];
[alertControllerMessageStr addAttribute:NSForegroundColorAttributeName value:[UIColor greenColor] range:NSMakeRange(0, 4)];
[alertControllerMessageStr addAttribute:NSFontAttributeName value:[UIFont systemFontOfSize:20] range:NSMakeRange(0, 4)];
if(alertController valueForKey:@"attributedMessage") {
[alertControllersetValue:alertControllerMessageStrforKey:@"attributedMessage"];
}
//修改按钮字体颜色
UIAlertAction *defaultAction = [UIAlertAction actionWithTitle:@"Default"style:UIAlertActionStyleDefault handler:nil];
[alertController addAction:defaultAction];
if(cancelAction valueForKey:@"titleTextColor") {
[cancelActionsetValue:[UIColor redColor]forKey:@"titleTextColor"];
}
五十五. 使用钥匙串保存设备唯一ID
//下载并倒入SSKeyChain的.h和.m文件，并添加Security.framework框架
+ (NSString *)getDeviceId{
NSString * currentDeviceUUIDStr = [SSKeychain passwordForService:@" "account:@"uuid"];
if(currentDeviceUUIDStr == nil || [currentDeviceUUIDStr isEqualToString:@""]) {
NSUUID * currentDeviceUUID = [UIDevice currentDevice].identifierForVendor;
currentDeviceUUIDStr = currentDeviceUUID.UUIDString;
currentDeviceUUIDStr = [currentDeviceUUIDStr stringByReplacingOccurrencesOfString:@"-"withString:@""];
currentDeviceUUIDStr = [currentDeviceUUIDStr lowercaseString];
[SSKeychainsetPassword: currentDeviceUUIDStrforService:@" "account:@"uuid"];
}
return currentDeviceUUIDStr;
}
五十六. 获取设备型号
//引入头文件
#include #include
+ (NSString *)getCurrentDeviceModel{
int mib[2];
size_t len;
char *machine;
mib[0] = CTL_HW;
mib[1] = HW_MACHINE;
sysctl(mib, 2, NULL, &len, NULL, 0);
machine = malloc(len);
sysctl(mib, 2, machine, &len, NULL, 0);
NSString *platform = [NSString stringWithCString:machine encoding:NSASCIIStringEncoding];
free(machine);
//iPhone
if([platform isEqualToString:@"iPhone1,1"])return@"iPhone2G";
if([platform isEqualToString:@"iPhone1,2"])return@"iPhone3G";
if([platform isEqualToString:@"iPhone2,1"])return@"iPhone3GS";
if([platform isEqualToString:@"iPhone3,1"])return@"iPhone4";
if([platform isEqualToString:@"iPhone3,2"])return@"iPhone4";
if([platform isEqualToString:@"iPhone3,3"])return@"iPhone4";
if([platform isEqualToString:@"iPhone4,1"])return@"iPhone4S";
if([platform isEqualToString:@"iPhone5,1"])return@"iPhone5";
if([platform isEqualToString:@"iPhone5,2"])return@"iPhone5";
if([platform isEqualToString:@"iPhone5,3"])return@"iPhone5c";
if([platform isEqualToString:@"iPhone5,4"])return@"iPhone5c";
if([platform isEqualToString:@"iPhone6,1"])return@"iPhone5s";
if([platform isEqualToString:@"iPhone6,2"])return@"iPhone5s";
if([platform isEqualToString:@"iPhone7,2"])return@"iPhone6";
if([platform isEqualToString:@"iPhone7,1"])return@"iPhone6Plus";
if([platform isEqualToString:@"iPhone8,1"])return@"iPhone6s";
if([platform isEqualToString:@"iPhone8,2"])return@"iPhone6sPlus";
if([platform isEqualToString:@"iPhone8,3"])return@"iPhoneSE";
if([platform isEqualToString:@"iPhone8,4"])return@"iPhoneSE";
if([platform isEqualToString:@"iPhone9,1"])return@"iPhone7";
if([platform isEqualToString:@"iPhone9,2"])return@"iPhone7Plus";
//iPod Touch
if([platform isEqualToString:@"iPod1,1"])return@"iPodTouch";
if([platform isEqualToString:@"iPod2,1"])return@"iPodTouch2G";
if([platform isEqualToString:@"iPod3,1"])return@"iPodTouch3G";
if([platform isEqualToString:@"iPod4,1"])return@"iPodTouch4G";
if([platform isEqualToString:@"iPod5,1"])return@"iPodTouch5G";
if([platform isEqualToString:@"iPod7,1"])return@"iPodTouch6G";
//iPad
if([platform isEqualToString:@"iPad1,1"])return@"iPad";
if([platform isEqualToString:@"iPad2,1"])return@"iPad2";
if([platform isEqualToString:@"iPad2,2"])return@"iPad2";
if([platform isEqualToString:@"iPad2,3"])return@"iPad2";
if([platform isEqualToString:@"iPad2,4"])return@"iPad2";
if([platform isEqualToString:@"iPad3,1"])return@"iPad3";
if([platform isEqualToString:@"iPad3,2"])return@"iPad3";
if([platform isEqualToString:@"iPad3,3"])return@"iPad3";
if([platform isEqualToString:@"iPad3,4"])return@"iPad4";
if([platform isEqualToString:@"iPad3,5"])return@"iPad4";
if([platform isEqualToString:@"iPad3,6"])return@"iPad4";
//iPad Air
if([platform isEqualToString:@"iPad4,1"])return@"iPadAir";
if([platform isEqualToString:@"iPad4,2"])return@"iPadAir";
if([platform isEqualToString:@"iPad4,3"])return@"iPadAir";
if([platform isEqualToString:@"iPad5,3"])return@"iPadAir2";
if([platform isEqualToString:@"iPad5,4"])return@"iPadAir2";
//iPad mini
if([platform isEqualToString:@"iPad2,5"])return@"iPadmini1G";
if([platform isEqualToString:@"iPad2,6"])return@"iPadmini1G";
if([platform isEqualToString:@"iPad2,7"])return@"iPadmini1G";
if([platform isEqualToString:@"iPad4,4"])return@"iPadmini2";
if([platform isEqualToString:@"iPad4,5"])return@"iPadmini2";
if([platform isEqualToString:@"iPad4,6"])return@"iPadmini2";
if([platform isEqualToString:@"iPad4,7"])return@"iPadmini3";
if([platform isEqualToString:@"iPad4,8"])return@"iPadmini3";
if([platform isEqualToString:@"iPad4,9"])return@"iPadmini3";
if([platform isEqualToString:@"iPad5,1"])return@"iPadmini4";
if([platform isEqualToString:@"iPad5,2"])return@"iPadmini4";
if([platform isEqualToString:@"i386"])return@"iPhoneSimulator";
if([platform isEqualToString:@"x86_64"])return@"iPhoneSimulator";
return platform;
}
五十七. 减少发布之后过多的NSLog带来的性能影响
#if defined(DEBUG)||defined(_DEBUG)NSLog(@"测试代码");
NSLog(@"Test Coding");
#endif
五十八. 去掉字符串的前后空格（基本用在textfield）
NSString *textName = [self.nameCell.textField.text stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
五十九. 截取字符串到指定字符的位置
NSString *string = @"abcdefghijklmn";
NSRange range = [string rangeOfString:@"h"];
string = [string substringToIndex:range.location];
六十. 获取label的行数和每行的内容
- (NSArray *)getLinesArrayOfStringInLabel:(UILabel *)label {
NSString *text = [label text];
UIFont *font = [label font];
CGRect rect = [label frame];
CTFontRef myFont = CTFontCreateWithName(( CFStringRef)([font fontName]), [font pointSize], NULL);
NSMutableAttributedString *attStr = [[NSMutableAttributedString alloc] initWithString:text];
[attStr addAttribute:(NSString *)kCTFontAttributeName value:(__bridge id)myFont range:NSMakeRange(0, attStr.length)];
CFRelease(myFont);
CTFramesetterRef frameSetter = CTFramesetterCreateWithAttributedString(( CFAttributedStringRef)attStr);
CGMutablePathRef path = CGPathCreateMutable(); CGPathAddRect(path, NULL, CGRectMake(0,0,rect.size.width,100000));
CTFrameRef frame = CTFramesetterCreateFrame(frameSetter, CFRangeMake(0, 0), path, NULL);
NSArray *lines = ( NSArray *)CTFrameGetLines(frame);
NSMutableArray *linesArray = [[NSMutableArray alloc]init];
for(id lineinlines) {
CTLineRef lineRef = (__bridge CTLineRef )line;
CFRange lineRange = CTLineGetStringRange(lineRef);
NSRange range = NSMakeRange(lineRange.location, lineRange.length);
NSString *lineString = [text substringWithRange:range]; CFAttributedStringSetAttribute((CFMutableAttributedStringRef)attStr, lineRange, kCTKernAttributeName, (CFTypeRef)([NSNumber numberWithFloat:0.0]));
CFAttributedStringSetAttribute((CFMutableAttributedStringRef)attStr, lineRange, kCTKernAttributeName, (CFTypeRef)([NSNumber numberWithInt:0.0]));
// NSLog(@"''''''''''''''''''%@",lineString);
[linesArray addObject:lineString];
}
CGPathRelease(path);
CFRelease( frame );
CFRelease(frameSetter);
return(NSArray *)linesArray;
}
六十一.键盘透明
[UITextField alloc].keyboardAppearance = UIKeyboardAppearanceAlert;
六十二.状态栏的网络活动风火轮是否旋转,默认为NO
[UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
六十三.开启右滑返回
self.navigationController.interactivePopGestureRecognizer.delegete = nil;
六十四.MD5加密
#import "NSString+MD5.h"#import
- (NSString *)stringToMD5:(NSString *)str {
//1.首先将字符串转换成UTF-8编码, 因为MD5加密是基于C语言的,所以要先把字符串转化成C语言的字符串
const char *fooData = [str UTF8String];
//2.然后创建一个字符串数组,接收MD5的值
unsigned char result[CC_MD5_DIGEST_LENGTH];
//3.计算MD5的值, 这是官方封装好的加密方法:把我们输入的字符串转换成16进制的32位数,然后存储到result中
CC_MD5(fooData, (CC_LONG)strlen(fooData), result);
/** 第一个参数:要加密的字符串 第二个参数: 获取要加密字符串的长度 第三个参数: 接收结果的数组 */
//4.创建一个字符串保存加密结果
NSMutableString *saveResult = [NSMutableString string];
//5.从result 数组中获取加密结果并放到 saveResult中
for (int i = 0; i < CC_MD5_DIGEST_LENGTH; i++) {
[saveResult appendFormat:@"%02x", result];
}
/** x表示十六进制，%02X 意思是不足两位将用0补齐，如果多余两位则不影响
NSLog("%02X", 0x888);
//888
NSLog("%02X", 0x4);
//04
*/
return saveResult;}
六十五.导航栏返回按钮颜色设置 及 文字变成<
-(void)UIBarButtonBackItemSet{
[[UIBarButtonItem appearance]setBackButtonTitlePositionAdjustment:UIOffsetMake(0, -60)forBarMetrics:UIBarMetricsDefault];
self.navigationController.navigationBar.barStyle = UIStatusBarStyleDefault;
[self.navigationController.navigationBarsetTintColor:[UIColor whiteColor]];}
六十六.字符串中包含双引号和反斜杠处理
NSString *testStr = @"你好，\"你好\"";
NSLog(@"%@",testStr);
//输出结果为：你好，"你好"
NSString *testStr = @"不好，\\不好\\\\";
NSLog(@"%@",testStr);
//输出结果为：不好，\不好\\
