iOS－－小知識點
一. 顏色漸變
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繪制簡單圖形
//獲取上下文 CGContextRef
context=UIGraphicsGetCurrentContext(); //設置繪制地區的顏色
CGContextSetRGBFillColor(context, 1, 0, 0, 1); //設置繪制的位置和大小
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. 可變數組與不可變數組之間的轉換
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. 對控件的旋轉，平移，縮放，復位
//平移
CGAffineTransform transForm = _pingyibu.transform;
_pingyibu.transform=CGAffineTransformTranslate(transForm, 100, 0);
//旋轉
_pingyibu.transform = CGAffineTransformRotate(transForm, M_PI_4);
//縮放按鈕
_pingyibu.transform = CGAffineTransformScale(transForm, 1.2, 1.2);
//初始化復位
_pingyibu.transform = CGAffineTransformIdentity;
七. 設置label的行間距
NSMutableAttributedString *attributedString = [[NSMutableAttributedString alloc] initWithString:_xuanzhuanla.text];
NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
[paragraphStylesetLineSpacing:3]; //調整行間距
[attributedString addAttribute:NSParagraphStyleAttributeName value:paragraphStyle range:NSMakeRange(0,[_xuanzhuanla.text length])];
_xuanzhuanla.attributedText = attributedString;
八. 讓應用直接閃退
AppDelegate *app = [UIApplication sharedApplication].delegate;
UIWindow *window = app.window;
[UIView animateWithDuration:1.0f animations:^{
window.alpha = 0;
} completion:^(BOOL finished) {
exit(0);
}];
九. 手機震動
AudioServicesPlaySystemSound(kSystemSoundID_Vibrate);
十一. label自適應高度
CGRect rect = [la.text boundingRectWithSize:CGSizeMake(WIDTH-70, MAXFLOAT) options:NSStringDrawingUsesLineFragmentOrigin|NSStringDrawingUsesFontLeading attributes:@{NSFontAttributeName:la.font} context:nil];
十三. image轉換成data類型
NSData *data=UIImagePNGRepresentation(image);
NSData *data=UIImageJPEGRepresentation(image, 1.0);
十四. 獲取當前時間和時間戳
//當前時間NSDate *senddate=[NSDate date];
NSDateFormatter *dateformatter=[[NSDateFormatter alloc] init];
[dateformattersetDateFormat:@"YYYY-MM-dd HH:mm:ss"];
NSString *locationString=[dateformatter stringFromDate:senddate];
//當前時間戳
NSDate* dat = [NSDate dateWithTimeIntervalSinceNow:0];
NSTimeInterval a=[dat timeIntervalSince1970];
NSString *timeString = [NSString stringWithFormat:@"%f", a];
long s = [timeString intValue];
十五. 對比時間差
-(int)max:(NSDate *)datatime {
//創建日期格式化對象
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];
//取兩個日期對象的時間間隔：
//這里的NSTimeInterval 并不是對象，是基本型，其實是double類型，是由c定義的:typedef double NSTimeInterval;
NSTimeInterval time=[date timeIntervalSinceDate:datatime];
int days=((int)time)/(3600*24);
return days;
}
十六. 使提示框消失（定時）
[alu dismissWithClickedButtonIndex:0 animated:NO];
十七. 設置self.title的顏色
UIColor *color = [UIColor whiteColor];
NSDictionary * dict=[NSDictionary dictionaryWithObject:colorforKey:UITextAttributeTextColor];
self.navigationController.navigationBar.titleTextAttributes = dict;
十八. 請求定位權限以及定位屬性
//定位管理器
_locationManager = [[CLLocationManager alloc]init];
//如果沒有授權則請求用戶授權
if([CLLocationManager authorizationStatus]==kCLAuthorizationStatusNotDetermined){
[_locationManager requestWhenInUseAuthorization];
} else if([CLLocationManager authorizationStatus]==kCLAuthorizationStatusAuthorizedWhenInUse){
//設置代理
_locationManager.delegate=self;
//設置定位精度
_locationManager.desiredAccuracy = kCLLocationAccuracyBest;
//定位頻率,每隔多少米定位一次
CLLocationDistance distance=10.0;
_locationManager.distanceFilter = distance;
//啟動跟蹤定位
[_locationManager startUpdatingLocation];
}
十九. 通過經緯度計算距離
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(@"距離:%f",kilometers);
if(kilometers >= 10) {
JuLi=YES;
}else{
JuLi=NO;
}
return JuLi;
二十. 彈出效果
/** 彈出對話框的動畫 動畫時長
@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. 設置TextField左右視圖
-(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. 常用宏定義
#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. 獲取版本號提示版本更新
-(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%@, 已經發布",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. 獲取設備或APP信息
//返回應用程序名稱
+(NSString *) getAppName{ NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
return[infoDictionary objectForKey:@"CFBundleDisplayName"];
}
//返回應用版本號+(NSString *) getAppVersion{ NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
return[infoDictionary objectForKey:@"CFBundleShortVersionString"];
}
+(NSString *) getAppBundleVersion{
NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
return [infoDictionary objectForKey:@"CFBundleVersion"];
}
//設備型號
+(NSString *) getSystemName{
return [[UIDevice currentDevice] systemName];
}
//設備版本號
+(NSString *) getSystemVersion{
return[[UIDevice currentDevice] systemVersion];
}
二十五. 內存泄漏分析
靜態分析內存泄露 使用Xcode自帶的Analyze功能
（Product-> Analyze）（Shift + Command + B），對代碼進行靜態分析，
對于內存泄露（Potential Memory Leak）, 未使用局部變量(dead store)，
邏輯錯誤(Logic Flaws)以及API使用問題(API-usage)等明確的展示出來。
靜態分析的內存泄露情況比較簡單，開發者都能很快的解決。這里不做贅述。
動態分析內存泄露 使用Xcode自帶的Profile功能
（Product-> Profile）（Command + i）彈出工具框，
選擇Leaks打開，選擇運行設備點左上角的Record錄制按鈕，
項目就會在已選好的設備上運行，并開始錄制內存檢測情況。
選Leaks查看泄露情況，在Leaks的詳細菜單Details選項里選調用樹Call Tree，
可查看所有內存泄露發生在哪些地方。
再在右側的齒輪設置-Call Tree-勾選Hide System Libraries，
則可直接看內存泄露發生的函數名、方法名。
點擊函數名、方法名，可直接跳到函數方法的細節，
可以看到哪一句代碼出現了內存泄露，以及泄露了多少內存。
接下來就要回到Xcode，找到出現內存泄露的函數方法，仔細分析如何出現的內存泄露;
一般使用ARC，按照上面一提到的內存理解和編碼習慣是不會出現內存泄露的。
但我們在開發過程中，經常要使用第三方的一些類庫，特別是涉及到加密的類庫，
用c或c++來編碼的加密解密方法，會出現內存泄露。
此時，我們要明白這些內存分配，需要手動釋放。
要一步一步看，哪里分配了內存，在使用完之后一定要記得釋放free它。
二十六. block循環利用導致內存泄漏
A *a = [[A alloc] init];
a.finishBlock = ^(NSDictionary paraments){
[adoSomething];
};
//對于這種在block塊里引用對象a的情況，要在創建對象a時加修飾符block來防止循環引用。
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中調用用self的方法、屬性、變量時，可以這樣寫
__weak typeof(self) weakSelf = self;
//在block中使用weakSelf。
__weak typeof(self) weakSelf = self;
[bdoSomethingWithFinishBlock:^{
weakSelf.text = @"內存檢測";
[weakSelfdoSomething];
}];
二十七. label 的空格屬性和局部字段顏色
//設置 label 的 autoresizingMask 為 NO ,可以使用空格間隔字符串!
NSMutableAttributedString *hintString=[[NSMutableAttributedString alloc]initWithString:@"點擊注冊按鈕服務協議"];
//獲取要調整顏色的文字位置,調整顏色
NSRange range1=[[hintString string]rangeOfString:@"注冊"];
[hintString addAttribute:NSForegroundColorAttributeName value:[UIColor greenColor] range:range1];
NSRange range2=[[hintString string]rangeOfString:@"服務協議"];
[hintString addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:range2];
hintLabel.attributedText=hintString;
二十八. 過濾特殊字符
// 定義一個特殊字符的集合
NSCharacterSet *set= [NSCharacterSet characterSetWithCharactersInString: @"@／：；（）￥「」＂、[]{}#%-*+=_\\|~＜＞$€^?'@#$%^&*()_+'\""];
// 過濾字符串的特殊字符
NSString *newString = [trimString stringByTrimmingCharactersInSet:set];
二十九. 設置滑動的時候隱藏 navigationbar
//第1種:
navigationController.hidesBarsOnSwipe = Yes
//第2種: 當我們的手離開屏幕時候隱藏
- (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這個量，在上滑和下滑時，變化極?。ㄐ担且驗榉较虿煌?，有正負之分，這就很好處理了。
三十. 屏幕截圖
// 1. 開啟一個與圖片相關的圖形上下文
UIGraphicsBeginImageContextWithOptions(self.view.bounds.size,NO,0.0);
// 2. 獲取當前圖形上下文
CGContextRef ctx = UIGraphicsGetCurrentContext();=
// 3. 獲取需要截取的view的layer
[self.view.layer renderInContext:ctx];
// 4. 從當前上下文中獲取圖片
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
// 5. 關閉圖形上下文
UIGraphicsEndImageContext();
// 6. 把圖片保存到相冊
UIImageWriteToSavedPhotosAlbum(image, nil, nil, nil);
三十一. 去掉 tabbar 和 navgationbar 的黑線
//去掉tabBar頂部線條
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. 判斷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. 解決父視圖和子視圖的手勢沖突問題
/** 解決手勢沖突 */
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch {
if([touch.view isDescendantOfView:cicView]) {
returnNO;
}
returnYES;
}
三十四. 獲取當前連接的Wi-Fi的名稱
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. 跨控制器跳轉返回
for(UIViewController *controllerinself.navigationController.viewControllers) {
if([controller isKindOfClass:[@“你要返回的控制器類名” class]])
{
[self.navigationController popToViewController:controller animated:YES];
}
}
三十六. layer.cornerRadius 圓角流暢性的優化
loginBtn.layer.rasterizationScale = [UIScreen mainScreen].scale;
三十七. 導航欄和下方視圖間隔距離消失
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. 移動工程不需要配置路徑
創建.pch文件時 , BuildSetting 中的 Prefix Header 中的路徑開頭可以寫 $(SRCROOT)/工程地址,
這樣寫的好處可以使你的挪動代碼不用手動更換路徑!
四十. 判斷兩個數組是否相同
NSArray *array1 = [NSArray arrayWithObjects:@"a", @"b", @"c", nil];
NSArray *array2 = [NSArray arrayWithObjects:@"d", @"a", @"c", nil];
bool bol =false;
//創建倆新的數組
NSMutableArray *oldArr = [NSMutableArray arrayWithArray:array1];
NSMutableArray *newArr = [NSMutableArray arrayWithArray:array2];
//對數組1排序
[oldArr sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {
return obj1 > obj2;
}];
//對數組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(@" ------------- 兩個數組的內容相同！");
}else{
NSLog(@"-=-------------兩個數組的內容不相同！");
}
四十一. block
對于block，都應該使用copy來聲明，
原因是block來捕獲上下文的信息
[官方文檔]
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. 計算一段NSString在視圖中渲染出來的尺寸
+ (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. 獲取相應的字體類型名
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約束TTTAttributedLabel的時候，
初始化TTTAttributedLabel需要設置frame為CGRectZero，
否則約束會不生效。
SVProgressHUD如果要自定義一些屬性，
比如loading狀態轉圈的顏色，
必須先設置style為SVProgressHUDStyleCustom，
這樣自定義的狀態才會生效。
四十六. 打印View所有子視圖
po [[self view]recursiveDescription]
四十七. layoutSubviews調用的調用時機
* 當視圖第一次顯示的時候會被調用
* 當這個視圖顯示到屏幕上了,點擊按鈕
* 添加子視圖也會調用這個方法
* 當本視圖的大小發生改變的時候是會調用的
* 當子視圖的frame發生改變的時候是會調用的
* 當刪除子視圖的時候是會調用的
四十八. UIImageView填充模式
@"UIViewContentModeScaleToFill", // 拉伸自適應填滿整個視圖
@"UIViewContentModeScaleAspectFit", // 自適應比例大小顯示
@"UIViewContentModeScaleAspectFill", // 原始大小顯示
@"UIViewContentModeRedraw", // 尺寸改變時重繪
@"UIViewContentModeCenter", // 中間
@"UIViewContentModeTop", // 頂部
@"UIViewContentModeBottom", // 底部
@"UIViewContentModeLeft", // 中間貼左
@"UIViewContentModeRight", // 中間貼右
@"UIViewContentModeTopLeft", // 貼左上
@"UIViewContentModeTopRight", // 貼右上
@"UIViewContentModeBottomLeft", // 貼左下
@"UIViewContentModeBottomRight", // 貼右下
四十九. MRC和ARC混編設置方式
在XCode中targets的build phases選項下Compile Sources下選擇 不需要arc編譯的文件
雙擊輸入 -fno-objc-arc 即可
MRC工程中也可以使用ARC的類，
方法如下：
在XCode中targets的build phases選項下Compile Sources下選擇要使用arc編譯的文件
雙擊輸入 -fobjc-arc 即可
五十. 解決tableview的分割線短一截
-(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字體顏色和大小
textField.placeholder = @"username is in here!";
[textFieldsetValue:[UIColor redColor]forKeyPath:@"_placeholderLabel.textColor"];
[textFieldsetValue:[UIFont boldSystemFontOfSize:16]forKeyPath:@"_placeholderLabel.font"];
五十二. 修改狀態欄字體顏色
//只能設置兩種顏色，黑色和白色，系統默認黑色
//設置為白色方法：
（1）在plist里面添加Status bar style，值為UIStatusBarStyleLightContent（白色）或UIStatusBarStyleDefault（黑 色）
（2）在Info.plist中設置UIViewControllerBasedStatusBarAppearance 為NO
五十三.調用相機后狀態欄消失
[[UIApplication sharedApplication]setStatusBarHidden:NO animated:NO];
[[UIApplication sharedApplication]setStatusBarStyle:UIStatusBarStyleBlackTranslucent animated:YES];
五十四. 修改UIAlertController字體顏色
//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:@"提示內容"];
[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"];
}
//修改按鈕字體顏色
UIAlertAction *defaultAction = [UIAlertAction actionWithTitle:@"Default"style:UIAlertActionStyleDefault handler:nil];
[alertController addAction:defaultAction];
if(cancelAction valueForKey:@"titleTextColor") {
[cancelActionsetValue:[UIColor redColor]forKey:@"titleTextColor"];
}
五十五. 使用鑰匙串保存設備唯一ID
//下載并倒入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. 獲取設備型號
//引入頭文件
#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. 減少發布之后過多的NSLog帶來的性能影響
#if defined(DEBUG)||defined(_DEBUG)NSLog(@"測試代碼");
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. 獲取label的行數和每行的內容
- (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.鍵盤透明
[UITextField alloc].keyboardAppearance = UIKeyboardAppearanceAlert;
六十二.狀態欄的網絡活動風火輪是否旋轉,默認為NO
[UIApplication sharedApplication].networkActivityIndicatorVisible = NO;
六十三.開啟右滑返回
self.navigationController.interactivePopGestureRecognizer.delegete = nil;
六十四.MD5加密
#import "NSString+MD5.h"#import
- (NSString *)stringToMD5:(NSString *)str {
//1.首先將字符串轉換成UTF-8編碼, 因為MD5加密是基于C語言的,所以要先把字符串轉化成C語言的字符串
const char *fooData = [str UTF8String];
//2.然后創建一個字符串數組,接收MD5的值
unsigned char result[CC_MD5_DIGEST_LENGTH];
//3.計算MD5的值, 這是官方封裝好的加密方法:把我們輸入的字符串轉換成16進制的32位數,然后存儲到result中
CC_MD5(fooData, (CC_LONG)strlen(fooData), result);
/** 第一個參數:要加密的字符串 第二個參數: 獲取要加密字符串的長度 第三個參數: 接收結果的數組 */
//4.創建一個字符串保存加密結果
NSMutableString *saveResult = [NSMutableString string];
//5.從result 數組中獲取加密結果并放到 saveResult中
for (int i = 0; i < CC_MD5_DIGEST_LENGTH; i++) {
[saveResult appendFormat:@"%02x", result];
}
/** x表示十六進制，%02X 意思是不足兩位將用0補齊，如果多余兩位則不影響
NSLog("%02X", 0x888);
//888
NSLog("%02X", 0x4);
//04
*/
return saveResult;}
六十五.導航欄返回按鈕顏色設置 及 文字變成<
-(void)UIBarButtonBackItemSet{
[[UIBarButtonItem appearance]setBackButtonTitlePositionAdjustment:UIOffsetMake(0, -60)forBarMetrics:UIBarMetricsDefault];
self.navigationController.navigationBar.barStyle = UIStatusBarStyleDefault;
[self.navigationController.navigationBarsetTintColor:[UIColor whiteColor]];}
六十六.字符串中包含雙引號和反斜杠處理
NSString *testStr = @"你好，\"你好\"";
NSLog(@"%@",testStr);
//輸出結果為：你好，"你好"
NSString *testStr = @"不好，\\不好\\\\";
NSLog(@"%@",testStr);
//輸出結果為：不好，\不好\\
