1.打印 View 所有子视图:
po [[self view]recursiveDescription]
2.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];
3.播放声音:
// 1. 获取音效资源的路径
NSString *path = [[NSBundle mainBundle]pathForResource:@"pour_milk" ofType:@"wav"];
// 2. 将路劲转化为 url
NSURL *tempUrl = [NSURL fileURLWithPath:path];
// 3. 用转化成的 url 创建一个播放器
NSError *error = nil;
AVAudioPlayer *play = [[AVAudioPlayer alloc]initWithContentsOfURL:tempUrl error:&error];
self.player = play;
// 4. 播放
[play play];
4.修改 UITextField 中 Placeholder 的文字颜色:
[text setValue:[UIColor redColor] forKeyPath:@"_placeholderLabel.textColor"];
5.判断 view 是不是指定视图的子视图:
BOOL isView = [textView isDescendantOfView:self.view];
6.判断对象是否遵循了某协议:
if ([self.selectedController conformsToProtocol:@protocol(RefreshPtotocol)])
{
[self.selectedController performSelector:@selector(onTriggerRefresh)];
}
7.系统键盘通知消息:
1、UIKeyboardWillShowNotification- 将要弹出键盘
2、UIKeyboardDidShowNotification- 显示键盘
3、UIKeyboardWillHideNotification- 将要隐藏键盘
4、UIKeyboardDidHideNotification- 键盘已经隐藏
5、UIKeyboardWillChangeFrameNotification- 键盘将要改变 frame
6、UIKeyboardDidChangeFrameNotification- 键盘已经改变 frame
8.关闭 navigationController 的滑动返回手势:
self.navigationController.interactivePopGestureRecognizer.enabled = NO;
9.设置状态栏背景为任意的颜色:
-(void)setStatusColor
{
UIView *statusBarView = [[UIView alloc] initWithFrame:CGRectMake(0, 0,[UIScreen mainScreen].bounds.size.width, 20)];
statusBarView.backgroundColor = [UIColor orangeColor];
[self.view addSubview:statusBarView];
}
10.Label 行间距:
-(void)test
{
NSMutableAttributedString *attributedString =
[[NSMutableAttributedString alloc] initWithString:self.contentLabel.text];
NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
[paragraphStyle setLineSpacing:3];
// 调整行间距
[attributedString addAttribute:NSParagraphStyleAttributeName
value:paragraphStyle
range:NSMakeRange(0, [self.contentLabel.text length])];
self.contentLabel.attributedText = attributedString;
}
11.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
12.iOS 中的一些手势:
轻击手势（TapGestureRecognizer）
轻扫手势（SwipeGestureRecognizer）
长按手势（LongPressGestureRecognizer）
拖动手势（PanGestureRecognizer）
捏合手势（PinchGestureRecognizer）
旋转手势（RotationGestureRecognizer）
13.字符串去除所有的空格:
[str stringByReplacingOccurrencesOfString:@" " withString:@""]
14.字符串去除首尾的空格:
[str stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]];
15.数组的排序(升序、降序及乱序):
#pragma mark -- 数组排序方法（升序）
- (void)arraySortASC {
//定义一个数字数组
// NSArray *array = @[@"B",@"E",@"A",@"D",@"C"];
//对数组进行排序
NSArray *result = [array sortedArrayUsingComparator:^NSComparisonResult(id _Nonnull obj1, id _Nonnull obj2) {
NSLog(@"%@~%@",obj1,obj2); //3~4 2~1 3~1 3~2
return [obj1 compare:obj2]; //升序
}];
NSLog(@"result=%@",result);
}
#pragma mark -- 数组排序方法（降序）
- (void)arraySortDESC{
//定义一个数字数组
NSArray *array = @[@(3),@(4),@(2),@(1)];
//对数组进行排序
NSArray *result = [array sortedArrayUsingComparator:^NSComparisonResult(id _Nonnull obj1, id _Nonnull obj2) {
NSLog(@"%@~%@",obj1,obj2); //3~4 2~1 3~1 3~2
return [obj2 compare:obj1]; //降序
}];
NSLog(@"result=%@",result);
}
#pragma mark -- 数组排序方法（乱序）
- (void)arraySortBreak{
//定义一个数字数组
NSArray *array = @[@(3),@(4),@(2),@(1),@(5),@(6),@(0)];
//对数组进行排序
NSArray *result = [array sortedArrayUsingComparator:^NSComparisonResult(id _Nonnull obj1, id _Nonnull obj2) {
NSLog(@"%@~%@",obj1,obj2);
//乱序
if (arc4random_uniform(2) == 0) {
return [obj2 compare:obj1]; //降序
}
else{
return [obj1 compare:obj2]; //升序
}
}];
NSLog(@"result=%@",result);
}
16.解决ios11的下移问题:
//解决ios11的下移问题
if ([_YDHomeTableView respondsToSelector:@selector(setContentInsetAdjustmentBehavior:)])
{
if (@available(iOS 11.0, *))
{
_YDHomeTableView.contentInsetAdjustmentBehavior = UIScrollViewContentInsetAdjustmentNever;
}
else {}
}
17.获取子视图所在的父视图:
-(UIViewController *)getViewController
{
UIViewController *VC = nil;
UIResponder *responder = self.nextResponder;
while (responder) {
if ([responder isKindOfClass:[UIViewController class]]) {
VC = (UIViewController *)responder;
break;
}
responder = responder.nextResponder;
}
return VC;
}
18.iOS获取汉字的拼音:
+(NSString *)transform:(NSString *)chinese
{
//将NSString装换成NSMutableString
NSMutableString *pinyin = [chinese mutableCopy];
//将汉字转换为拼音(带音标)
CFStringTransform((__bridge CFMutableStringRef)pinyin, NULL, kCFStringTransformMandarinLatin, NO);
NSLog(@"%@", pinyin);
//去掉拼音的音标
CFStringTransform((__bridge CFMutableStringRef)pinyin, NULL, kCFStringTransformStripCombiningMarks, NO);
NSLog(@"%@", pinyin);
//返回最近结果
return pinyin;
}
19.改变UITableViewHeaderFooterView的背景色:
-(instancetype)initWithReuseIdentifier:(NSString *)reuseIdentifier
{
self = [super initWithReuseIdentifier:reuseIdentifier];
if (self) {
[self.contentView setBackgroundColor:[[UIColor whiteColor] colorWithAlphaComponent:0.5]];
self.backgroundView = ({
UIView * view = [[UIView alloc] initWithFrame:self.bounds];
view.backgroundColor = [[UIColor whiteColor] colorWithAlphaComponent:0.5];
view;
});
}
return self;
}
20.Base64编码与NSString对象或NSData对象的转换:
// Create NSData object
NSData *nsdata = [@"iOS Developer Tips encoded in Base64"
dataUsingEncoding:NSUTF8StringEncoding];
// Get NSString from NSData object in Base64
NSString *base64Encoded = [nsdata base64EncodedStringWithOptions:0];
// Print the Base64 encoded string
NSLog(@"Encoded: %@", base64Encoded);
// Let's go the other way...
// NSData from the Base64 encoded str
NSData *nsdataFromBase64String = [[NSData alloc]
initWithBase64EncodedString:base64Encoded options:0];
// Decoded NSString from the NSData
NSString *base64Decoded = [[NSString alloc]
initWithData:nsdataFromBase64String encoding:NSUTF8StringEncoding];
NSLog(@"Decoded: %@", base64Decoded);
21.UIImage 占用内存大小:
UIImage *image = [UIImage imageNamed:@"aa"];
NSUInteger size = CGImageGetHeight(image.CGImage) * CGImageGetBytesPerRow(image.CGImage);
22.GCD timer定时器:
dispatch_queue_t queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
dispatch_source_t timer = dispatch_source_create(DISPATCH_SOURCE_TYPE_TIMER, 0, 0,queue);
dispatch_source_set_timer(timer,dispatch_walltime(NULL, 0),1.0*NSEC_PER_SEC, 0); //每秒执行
dispatch_source_set_event_handler(timer, ^{
//@"倒计时结束，关闭"
dispatch_source_cancel(timer);
dispatch_async(dispatch_get_main_queue(), ^{
});
});
dispatch_resume(timer);
23.计算文件大小:
//文件大小
- (long long)fileSizeAtPath:(NSString *)path
{
NSFileManager *fileManager = [NSFileManager defaultManager];
if ([fileManager fileExistsAtPath:path])
{
long long size = [fileManager attributesOfItemAtPath:path error:nil].fileSize;
return size;
}
return 0;
}
//文件夹大小
- (long long)folderSizeAtPath:(NSString *)path
{
NSFileManager *fileManager = [NSFileManager defaultManager];
long long folderSize = 0;
if ([fileManager fileExistsAtPath:path])
{
NSArray *childerFiles = [fileManager subpathsAtPath:path];
for (NSString *fileName in childerFiles)
{
NSString *fileAbsolutePath = [path stringByAppendingPathComponent:fileName];
if ([fileManager fileExistsAtPath:fileAbsolutePath])
{
long long size = [fileManager attributesOfItemAtPath:fileAbsolutePath error:nil].fileSize;
folderSize += size;
}
}
}
return folderSize;
}
24.字符串中是否含有中文:
+(BOOL)checkIsChinese:(NSString *)string
{
for (int i=0; i<string.length; i++)
{
unichar ch = [string characterAtIndex:i];
if (0x4E00 <= ch && ch <= 0x9FA5)
{
return YES;
}
}
return NO;
}
25.禁止手机睡眠:
[UIApplication sharedApplication].idleTimerDisabled = YES;
26.去除数组中重复的对象:
NSArray *newArr = [oldArr valueForKeyPath:@"distinctUnionOfObjects.self"];
27.给view截图:
UIGraphicsBeginImageContextWithOptions(view.bounds.size, YES, 0.0);
[view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
28.获取window的方法:
+(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;
}
29.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;
}
30.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];
}
31.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";
case 0x89:
return @"png";
case 0x47:
return @"gif";
case 0x49:
case 0x4D:
return @"tiff";
case 0x52:
if ([data length] < 12) {
return nil;
}
NSString *testString = [[NSString alloc] initWithData:[data subdataWithRange:NSMakeRange(0, 12)] encoding:NSASCIIStringEncoding];
if ([testString hasPrefix:@"RIFF"]
&& [testString hasSuffix:@"WEBP"])
{
return @"webp";
}
return nil;
}
return nil;
}
32.圆形图片:
-(instancetype)circleImage
{
// 开启图形上下文
UIGraphicsBeginImageContext(self.size);
// 获得上下文
CGContextRef ctx = UIGraphicsGetCurrentContext();
// 矩形框
CGRect rect = CGRectMake(0, 0, self.size.width, self.size.height);
// 添加一个圆
CGContextAddEllipseInRect(ctx, rect);
// 裁剪(裁剪成刚才添加的图形形状)
CGContextClip(ctx);
// 往圆上面画一张图片
[self drawInRect:rect];
// 获得上下文中的图片
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
// 关闭图形上下文
UIGraphicsEndImageContext();
return image;
}
33.验证身份证号:
-(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];
}
34.给imageView添加倒影:
CGRect frame = self.frame;
frame.origin.y += (frame.size.height + 1);
UIImageView *reflectionImageView = [[UIImageView alloc] initWithFrame:frame];
self.clipsToBounds = TRUE;
reflectionImageView.contentMode = self.contentMode;
[reflectionImageView setImage:self.image];
reflectionImageView.transform = CGAffineTransformMakeScale(1.0, -1.0);
CALayer *reflectionLayer = [reflectionImageView layer];
CAGradientLayer *gradientLayer = [CAGradientLayer layer];
gradientLayer.bounds = reflectionLayer.bounds;
gradientLayer.position = CGPointMake(reflectionLayer.bounds.size.width / 2, reflectionLayer.bounds.size.height * 0.5);
gradientLayer.colors = [NSArray arrayWithObjects:
(id)[[UIColor clearColor] CGColor],
(id)[[UIColor colorWithRed:1.0 green:1.0 blue:1.0 alpha:0.3] CGColor], nil];
gradientLayer.startPoint = CGPointMake(0.5,0.5);
gradientLayer.endPoint = CGPointMake(0.5,1.0);
reflectionLayer.mask = gradientLayer;
[self.superview addSubview:reflectionImageView];
35.获取视频的第一帧图片:
NSURL *url = [NSURL URLWithString:filepath];
AVURLAsset *asset1 = [[AVURLAsset alloc] initWithURL:url options:nil];
AVAssetImageGenerator *generate1 = [[AVAssetImageGenerator alloc] initWithAsset:asset1];
generate1.appliesPreferredTrackTransform = YES;
NSError *err = NULL;
CMTime time = CMTimeMake(1, 2);
CGImageRef oneRef = [generate1 copyCGImageAtTime:time actualTime:NULL error:&err];
UIImage *one = [[UIImage alloc] initWithCGImage:oneRef];
return one;
36.删除UIButton的所有点击事件:
[testButton removeTarget:nil action:nil forControlEvents:UIControlEventAllEvents];
37.删除某个view所有的子视图:
[[self.view subviews] makeObjectsPerformSelector:@selector(removeFromSuperview)];
38.UITextView中打开或禁用复制，剪切，选择，全选等功能:
// 继承UITextView重写这个方法
-(BOOL)canPerformAction:(SEL)action withSender:(id)sender
{
// 返回NO为禁用，YES为开启
// 粘贴
if (action == @selector(paste:)) return NO;
// 剪切
if (action == @selector(cut:)) return NO;
// 复制
if (action == @selector(copy:)) return NO;
// 选择
if (action == @selector(select:)) return NO;
// 选中全部
if (action == @selector(selectAll:)) return NO;
// 删除
if (action == @selector(delete:)) return NO;
// 分享
if (action == @selector(share)) return NO;
return [super canPerformAction:action withSender:sender];
}
39.字符串反转:
//第一种：
- (NSString *)reverseWordsInString:(NSString *)str
{
NSMutableString *newString = [[NSMutableString alloc] initWithCapacity:str.length];
for (NSInteger i = str.length - 1; i >= 0 ; i --)
{
unichar ch = [str characterAtIndex:i];
[newString appendFormat:@"%c", ch];
}
return newString;
}
//第二种：
- (NSString*)reverseWordsInString:(NSString*)str
{
NSMutableString *reverString = [NSMutableString stringWithCapacity:str.length];
[str enumerateSubstringsInRange:NSMakeRange(0, str.length) options:NSStringEnumerationReverse | NSStringEnumerationByComposedCharacterSequences usingBlock:^(NSString *substring, NSRange substringRange, NSRange enclosingRange, BOOL *stop) {
[reverString appendString:substring];
}];
return reverString;
}
40.UIView设置部分圆角（左上，右上，左下，右下）:
CGRect rect = view.bounds;
CGSize radio = CGSizeMake(30, 30);//圆角尺寸
UIRectCorner corner = UIRectCornerTopLeft|UIRectCornerTopRight;//这是圆角位置
UIBezierPath *path = [UIBezierPath bezierPathWithRoundedRect:rect byRoundingCorners:corner cornerRadii:radio];
CAShapeLayer *masklayer = [[CAShapeLayer alloc]init];//创建shapelayer
masklayer.frame = view.bounds;
masklayer.path = path.CGPath;//设置路径
view.layer.mask = masklayer;
41.禁用emoji:
- (NSString *)disable_emoji:(NSString *)text
{
NSRegularExpression *regex = [NSRegularExpression regularExpressionWithPattern:@"[^\\u0020-\\u007E\\u00A0-\\u00BE\\u2E80-\\uA4CF\\uF900-\\uFAFF\\uFE30-\\uFE4F\\uFF00-\\uFFEF\\u0080-\\u009F\\u2000-\\u201f\r\n]" options:NSRegularExpressionCaseInsensitive error:nil];
NSString *modifiedString = [regex stringByReplacingMatchesInString:text options:0 range:NSMakeRange(0, [text length]) withTemplate:@""];
return modifiedString;
}
42.UIAlertController颜色字号更改:
NSMutableAttributedString *attTitle = [[NSMutableAttributedString alloc]initWithString:@"标题1" attributes:@{NSForegroundColorAttributeName:[UIColor blueColor],NSFontAttributeName:[UIFont systemFontOfSize:17]}];
NSMutableAttributedString *attMessage = [[NSMutableAttributedString alloc]initWithString:@"message" attributes:@{NSForegroundColorAttributeName:[UIColor purpleColor],NSFontAttributeName:[UIFont systemFontOfSize:14]}];
UIAlertController *action = [UIAlertController alertControllerWithTitle:@"标题1" message:@"message" preferredStyle:UIAlertControllerStyleActionSheet];
[action setValue:attTitle forKey:@"attributedTitle"];
[action setValue:attMessage forKey:@"attributedMessage"];
UIAlertAction *alert1 = [UIAlertAction actionWithTitle:@"拍照" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
[self loadCamera];
}];
[alert1 setValue:[UIColor cyanColor] forKey:@"titleTextColor"];
[action addAction:alert1];
UIAlertAction *alert2 = [UIAlertAction actionWithTitle:@"从相册选择照片" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
[self loadPhotoLibraryPhoto];
}];
[alert2 setValue:[UIColor brownColor] forKey:@"titleTextColor"];
[action addAction:alert2];
UIAlertAction *cancelAlert = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:^(UIAlertAction * _Nonnull action) {
}];
[cancelAlert setValue:[UIColor redColor] forKey:@"titleTextColor"];
[action addAction:cancelAlert];
[self presentViewController:action animated:YES completion:nil];
43.UILabel下划线:
UILabel *testLabel = [[UILabel alloc]initWithFrame:CGRectMake(0, 120, 200, 30)];
testLabel.backgroundColor = [UIColor lightGrayColor];
testLabel.textAlignment = NSTextAlignmentCenter;
NSString *cstrTitle = @"This is an attributed string.下划线";
NSDictionary *attribtDic = @{NSUnderlineStyleAttributeName: [NSNumber numberWithInteger:NSUnderlineStyleSingle]};
NSMutableAttributedString *attribtStr = [[NSMutableAttributedString alloc]initWithString:cstrTitle attributes:attribtDic];
testLabel.attributedText = attribtStr;
[self.view addSubview:testLabel];
44.view添加虚线边框:
CAShapeLayer *border = [CAShapeLayer layer];
border.strokeColor = [UIColor colorWithRed:67/255.0f green:37/255.0f blue:83/255.0f alpha:1].CGColor;
border.fillColor = nil;
border.lineDashPattern = @[@4, @2];
border.path = [UIBezierPath bezierPathWithRect:view.bounds].CGPath;
border.frame = view.bounds;
[view.layer addSublayer:border];
45.UIImage和base64互转:
-(NSString *)encodeToBase64String:(UIImage *)image {
return [UIImagePNGRepresentation(image) base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];
}
-(UIImage *)decodeBase64ToImage:(NSString *)strEncodeData {
NSData *data = [[NSData alloc]initWithBase64EncodedString:strEncodeData options:NSDataBase64DecodingIgnoreUnknownCharacters];
return [UIImage imageWithData:data];
}
46.UILabel显示不同颜色字体和行间距:
NSMutableAttributedString *attrString = [[NSMutableAttributedString alloc] initWithString:label.text];
//行间距
NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc] init];
[style setLineSpacing:20];
[attrString addAttribute:NSParagraphStyleAttributeName value:style range:NSMakeRange(0, label.text.length)];
//不同颜色
[string addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:NSMakeRange(0,5)];
[string addAttribute:NSForegroundColorAttributeName value:[UIColor greenColor] range:NSMakeRange(5,6)];
[string addAttribute:NSForegroundColorAttributeName value:[UIColor blueColor] range:NSMakeRange(11,5)];
label.attributedText = attrString;
47.判断一个字符串是否为数字:
NSString *testString = @"123wo";
NSCharacterSet *notDigits = [[NSCharacterSet decimalDigitCharacterSet] invertedSet];
if ([testString rangeOfCharacterFromSet:notDigits].location == NSNotFound)
{
// 是数字
} else
{
// 不是数字
}
48.获取当前导航控制器下前一个控制器:
-(UIViewController *)backViewController
{
NSInteger myIndex = [self.navigationController.viewControllers indexOfObject:self];
if ( myIndex != 0 && myIndex != NSNotFound ) {
return [self.navigationController.viewControllers objectAtIndex:myIndex-1];
} else {
return nil;
}
}
49.让导航控制器pop回指定的控制器:
NSMutableArray *allViewControllers = [NSMutableArray arrayWithArray:[self.navigationController viewControllers]];
for (UIViewController *subVC in allViewControllers) {
if ([subVC isKindOfClass:[CommunityViewController class]]) {
[self.navigationController popToViewController:subVC animated:NO];
}
}
50.UIWebView添加单击手势不响应:
UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(webViewClick)];
tap.delegate = self;
[self.webView addGestureRecognizer:tap];
//因为webView本身有一个单击手势，所以再添加会造成手势冲突，从而不响应。需要绑定手势代理，遵循UIGestureRecognizerDelegate并实现下边的代理方法
-(BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{
return YES;
}
51.设置UITextField光标位置:
//index要设置的光标位置
-(void)cursorLocation:(UITextField *)textField index:(NSInteger)index
{
NSRange range = NSMakeRange(index, 0);
UITextPosition *start = [textField positionFromPosition:[textField beginningOfDocument] offset:range.location];
UITextPosition *end = [textField positionFromPosition:start offset:range.length];
[textField setSelectedTextRange:[textField textRangeFromPosition:start toPosition:end]];
}
52.去除webView黑底:
[webView setBackgroundColor:[UIColor clearColor]];
[webView setOpaque:NO];
for (UIView *subView in [webView subviews])
{
if ([subView isKindOfClass:[UIScrollView class]])
{
for (UIView *v2 in subView.subviews)
{
if ([v2 isKindOfClass:[UIImageView class]])
{
v2.hidden = YES;
}
}
}
}
53.解决openUrl延时问题:
//方法一
dispatch_async(dispatch_get_main_queue(), ^{
UIApplication *application = [UIApplication sharedApplication];
if ([application respondsToSelector:@selector(openURL:options:completionHandler:)]) {
[application openURL:URL options:@{}
completionHandler:nil];
} else {
[application openURL:URL];
}
});
// 方法二
[self performSelector:@selector(redirectToURL:) withObject:url afterDelay:0.1];
-(void)redirectToURL
{
UIApplication *application = [UIApplication sharedApplication];
if ([application respondsToSelector:@selector(openURL:options:completionHandler:)]) {
[application openURL:URL options:@{}
completionHandler:nil];
} else {
[application openURL:URL];
}
}
54.UITextField 只能输入数字和字母:
[[NSNotificationCenter defaultCenter] addObserver:self
selector:@selector(textFieldChanged:)
name:UITextFieldTextDidChangeNotification
object:nil];
监听name:UITextFieldTextDidChangeNotification 和 - (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string 来实现。
- (BOOL)validatePasswordString:(NSString *)resultMStr
{
BOOL result = YES;
switch (self.mode) {
case HXSChangePasswordLogin: {
NSString *regex = @"^[a-zA-Z0-9]+$";
NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];
result = [pred evaluateWithObject:resultMStr];
break;
}
case HXSChangePasswordPay: {
NSString *regex = @"^[0-9]+$";
NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];
result = [pred evaluateWithObject:resultMStr];
break;
}
}
return result;
}
55.退出app:
- (void)exitApplication{
AppDelegate *app = (AppDelegate *)[UIApplication sharedApplication].delegate;
UIWindow *window = app.window;
[UIView animateWithDuration:0.5f animations:^{
window.alpha = 0;
window.frame = CGRectMake(0, window.bounds.size.width, 0, 0);
} completion:^(BOOL finished) {
exit(0);
}];
}
56.返回当前星期几:
- (NSString*)toWeekString
{
static NSCalendar *calendar;
if (calendar == nil) {
calendar =
[[NSCalendar alloc] initWithCalendarIdentifier:NSGregorianCalendar];
}
unsigned unitFlags = NSWeekdayCalendarUnit;
NSDateComponents *comps = [calendar components:unitFlags fromDate:self];
NSArray *weekArr =
[NSArray arrayWithObjects:@"日",@"一",@"二",@"三",@"四",@"五",@"六", nil];
return [NSString stringWithFormat:@"星期%@",
[weekArr objectAtIndex:[comps weekday]-1]];
}
57.tableview中隐藏没有内容的cell:
self.tableView.tableFooterView = [[UIView alloc] init];
58.像Safari一样滑动时隐藏navigationbar:
self.navigationController.hidesBarsOnSwipe = YES;
59.ScrollView莫名其妙不能在viewController划到顶:
self.automaticallyAdjustsScrollViewInsets = NO;
60.点击self.view就让键盘收起:
-(void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
[self.view endEditing:YES];
}
61.用UIImagePickerController会导致我的statusbar的样式变成黑色:
-(void)navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewController animated:(BOOL)animated
{
[[UIApplication sharedApplication] setStatusBarStyle:UIStatusBarStyleLightContent];
}
62.navigationbar变成透明的而不是带模糊的效果:
[self.navigationBar setBackgroundImage:[UIImage new] forBarMetrics:UIBarMetricsDefault];
self.navigationBar.shadowImage = [UIImage new];
self.navigationBar.translucent = YES;
63.改变uitextfield placeholder的颜色和位置:
-(void) drawPlaceholderInRect:(CGRect)rect
{
[[UIColor blueColor] setFill];
[self.placeholder drawInRect:rect withFont:self.font lineBreakMode:UILineBreakModeTailTruncation alignment:self.textAlignment];
}
64.左右抖动动画:
//1.创建核心动画
CAKeyframeAnimation *keyAnima = [CAKeyframeAnimation animation];
//2.告诉系统执行什么动画。
keyAnima.keyPath = @"transform.rotation"; keyAnima.values = @[@(-M_PI_4 /90.0 * 5),@(M_PI_4 /90.0 * 5),@(-M_PI_4 /90.0 * 5)];
//3.执行完之后不删除动画
keyAnima.removedOnCompletion = NO;
//4.执行完之后保存最新的状态
keyAnima.fillMode = kCAFillModeForwards;
//5.动画执行时间
keyAnima.duration = 0.2;
//6.设置重复次数。
keyAnima.repeatCount = MAXFLOAT;
//7.添加核心动画
[self.iconView.layer addAnimation:keyAnima forKey:nil];
65.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);
66.强制横屏:
#pragma mark - 强制横屏代码
-(BOOL)shouldAutorotate
{
//是否支持转屏
return NO;
}
-(UIInterfaceOrientationMask)supportedInterfaceOrientations
{
//支持哪些转屏方向
return UIInterfaceOrientationMaskLandscape;
}
-(UIInterfaceOrientation)preferredInterfaceOrientationForPresentation
{
return UIInterfaceOrientationLandscapeRight;
}
-(BOOL)prefersStatusBarHidden
{
return NO;
}
67.应用程序的生命周期:
//1.启动但还没进入状态保存 ：
-(BOOL)application:(UIApplication *)application willFinishLaunchingWithOptions:(NSDictionary *)launchOptions
//2.基本完成程序准备开始运行：
-(BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
//3.当应用程序将要入非活动状态执行，应用程序不接收消息或事件，比如来电话了：
-(void)applicationWillResignActive:(UIApplication *)application
//4.当应用程序入活动状态执行，这个刚好跟上面那个方法相反：
-(void)applicationDidBecomeActive:(UIApplication *)application
//5.当程序被推送到后台的时候调用。所以要设置后台继续运行，则在这个函数里面设置即可：
-(void)applicationDidEnterBackground:(UIApplication *)application
//6.当程序从后台将要重新回到前台时候调用，这个刚好跟上面的那个方法相反：
-(void)applicationWillEnterForeground:(UIApplication *)application
//7.当程序将要退出是被调用，通常是用来保存数据和一些退出前的清理工作：
-(void)applicationWillTerminate:(UIApplication *)application
68.视图的生命周期:
1. alloc 创建对象，分配空间
2. init (initWithNibName) 初始化对象，初始化数据
3. loadView 从nib载入视图 ，除非你没有使用xib文件创建视图
4. viewDidLoad 载入完成，可以进行自定义数据以及动态创建其他控件
5. viewWillAppear视图将出现在屏幕之前，马上这个视图就会被展现在屏幕上了
6. viewDidAppear 视图已在屏幕上渲染完成
7. viewWillDisappear 视图将被从屏幕上移除之前执行
8. viewDidDisappear 视图已经被从屏幕上移除，用户看不到这个视图了
9. dealloc 视图被销毁，此处需要对你在init和viewDidLoad中创建的对象进行释放
viewVillUnload－ 当内存过低，即将释放时调用；viewDidUnload－当内存过低，释放一些不需要的视图时调用。
69.设置按钮字体居右:
btn.contentHorizontalAlignment = UIControlContentHorizontalAlignmentRight;
70.单选:
-(void)ButtonAction:(UIButton*)btn
{
NSPredicate*pre = [NSPredicatepredicateWithFormat:@"SELF.isSelected == YES"];
NSArray *selectArray = [_buttonArrayfilteredArrayUsingPredicate:pre];
[selectArrayenumerateObjectsUsingBlock:^(UIButton*_Nonnullobj,NSUIntegeridx,BOOL*_Nonnullstop) {
obj.selected=NO;
obj.backgroundColor= [UIColorwhiteColor];
obj.layer.borderColor=SAColorByRGB(235,235,235).CGColor;
}];
btn.selected=YES;
}
71.label字体自适应:
label.adjustsFontSizeToFitWidth = YES;
72.注册截屏通知:
[[NSNotificationCenterdefaultCenter]addObserver:self selector:@selector(userDidTakeScreenshot:) name:UIApplicationUserDidTakeScreenshotNotification object:nil];
//截屏响应
-(void)userDidTakeScreenshot:(NSNotification*)notification
{
[selfperformSelector:@selector(showNotification)withObject:nilafterDelay:0.5];
}
-(void)showNotification
{
[SANotificationViewshowNotificationViewWithContent:NSLocalizedString(@"已截屏，是要吐槽么？",nil)type:SANotificationViewTypeScreenShotsdidClick:nil];
}
73.取消searchbar背景色:
-(UISearchBar*)searchBar
{
if(!_searchBar) {
_searchBar= [[UISearchBaralloc]init];
_searchBar.backgroundImage= [selfimageWithColor:[UIColorclearColor]size:CGSizeMake(4,4)];
_searchBar.barStyle=UIBarStyleDefault;
_searchBar.layer.cornerRadius=5;
_searchBar.clipsToBounds=YES;
_searchBar.backgroundColor=SAColorByRGB(243.0,243.0,243.0);
_searchBar.placeholder=NSLocalizedString(@"搜索",nil);
UITextField*field = [_searchBarvalueForKey:@"_searchField"];
field.backgroundColor=SAColorByRGB(243.0,243.0,243.0);
field.textColor=SAColorByRGB(51.0,51.0,51.0);
field.font= [UIFontsystemFontOfSize:12];
UIImage*image = [UIImageimageNamed:@"icon_search"];
UIImageView*iconView = [[UIImageViewalloc]initWithImage:image];
iconView.contentMode=UIViewContentModeCenter;
iconView.frame=CGRectMake(0,0, image.size.width,28);
field.leftView= iconView;
[[NSNotificationCenterdefaultCenter]addObserver:selfselector:@selector(didChange:)name:UITextFieldTextDidChangeNotificationobject:nil];
}
return_searchBar;
}
-(UIImage*)imageWithColor:(UIColor*)color size:(CGSize)size
{
CGRectrect = CGRectMake(0,0, size.width, size.height);
UIGraphicsBeginImageContext(rect.size);
CGContextRefcontext = UIGraphicsGetCurrentContext();
CGContextSetFillColorWithColor(context, [colorCGColor]);
CGContextFillRect(context, rect);
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
74.判断手机号:
NSString *phoneRegex = @"(\\\\+\\\\d+)?1[34578]\\\\d{9}$";
NSPredicate *phoneTest = [NSPredicatepredicateWithFormat:@"SELF MATCHES %@", phoneRegex];
return [phoneTestevaluateWithObject:string];
75.判断邮箱:
NSString *emailRegex = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\\\.[A-Za-z]{2,4}";
76.改变图片透明度:
-(UIImage*)sa_imageWithAlpha:(CGFloat)alpha
{
if(alpha>1.0) {
alpha =1.0;
}
if(alpha<=0.0) {
alpha =0.0;
}
UIGraphicsBeginImageContextWithOptions(self.size,NO,0.0f);
CGContextRefctx =UIGraphicsGetCurrentContext();
CGRectarea =CGRectMake(0,0,self.size.width,self.size.height);
CGContextScaleCTM(ctx,1, -1);
CGContextTranslateCTM(ctx,0, -area.size.height);
CGContextSetBlendMode(ctx,kCGBlendModeMultiply);
CGContextSetAlpha(ctx, alpha);
CGContextDrawImage(ctx, area,self.CGImage);
UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return newImage;
}
77.任意改变图片尺寸:
-(UIImage*)sa_imageWithSize:(CGSize)size
{
UIGraphicsBeginImageContext(CGSizeMake(size.width, size.height));
[selfdrawInRect:CGRectMake(0,0, size.width, size.height)];
UIImage*resizedImage =UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return resizedImage;
}
78.等比例放缩图片:
-(UIImage*)sa_imageStretchWithScale:(CGFloat)scale
{
UIGraphicsBeginImageContext(CGSizeMake(self.size.width* scale,self.size.height* scale));
[selfdrawInRect:CGRectMake(0,0,self.size.width* scale,self.size.height* scale)];
UIImage*scaledImage =UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return scaledImage;
}
79.图片压缩（返回NSData 压缩比例0.0~1.0）:
-(NSData*)sa_imageCompressReturnDataWithRatio:(CGFloat)ratio
{
//UIImageJPEGRepresentation和UIImagePNGRepresentation
if(ratio>1.0) {
ratio =1.0;
}
if(ratio<=0) {
ratio =0.0;
}
NSData*compressedData =UIImageJPEGRepresentation(self, ratio);
return compressedData;
}
80.图片压缩 （返回UIImage 压缩比例0.0~1.0）:
-(UIImage*)sa_imageCompressReturnImageWithRatio:(CGFloat)ratio {
//UIImageJPEGRepresentation和UIImagePNGRepresentation
if(ratio>1.0) {
ratio =1.0;
}
if(ratio<=0) {
ratio =0.0;
}
NSData*compressedData =UIImageJPEGRepresentation(self, ratio);
UIImage*compressedImage = [UIImageimageWithData:compressedData];
return compressedImage;
}
81.将UIView转化成图片:
-(UIImage*)sa_getImageFromView:(UIView*)theView
{
UIGraphicsBeginImageContextWithOptions(theView.bounds.size,YES, theView.layer.contentsScale);
[theView.layerrenderInContext:UIGraphicsGetCurrentContext()];
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return image;
}
82.两张图片叠加、合成:
-(UIImage*)sa_integrateImageWithRect:(CGRect)rect andAnotherImage:(UIImage*)anotherImage anotherImageRect:(CGRect)anotherRect integratedImageSize:(CGSize)size
{
UIGraphicsBeginImageContext(size);
[selfdrawInRect:rect];
[anotherImagedrawInRect:anotherRect];
UIImage*integratedImage =UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return integratedImage;
}
83.图片添加水印:
/**
图片添加水印
@param markImage水印图片
@param imgRect水印图片对于原图片的rect
@param alpha水印图片透明度
@param markStr水印文字
@param strRect水印文字对于原图片的rect
@param attribute水印文字的设置颜色、字体大小
@return添加水印后的图片
*/
-(UIImage*)sa_imageWaterMark:(UIImage*)markImage imageRect:(CGRect)imgRect markImageAlpha:(CGFloat)alpha markString:(NSString*)markStr stringRect:(CGRect)strRect stringAttribute:(NSDictionary*)attribute
{
UIGraphicsBeginImageContext(self.size);
[selfdrawInRect:CGRectMake(0,0,self.size.width,self.size.height)blendMode:kCGBlendModeNormalalpha:1.0];
if(markImage)
{
[markImagedrawInRect:imgRectblendMode:kCGBlendModeNormalalpha:alpha];
}
if(markStr) {
//UILabel convertto UIImage
UILabel*markStrLabel = [[UILabelalloc]initWithFrame:CGRectMake(0,0, strRect.size.width, strRect.size.height)];
markStrLabel.textAlignment=NSTextAlignmentCenter;
markStrLabel.numberOfLines=0;
markStrLabel.attributedText= [[NSAttributedStringalloc]initWithString:markStrattributes:attribute];
UIImage*image = [selfsa_getImageFromView:markStrLabel];
[imagedrawInRect:strRectblendMode:kCGBlendModeNormalalpha:1.0];;
}
UIImage*waterMarkedImage =UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
return waterMarkedImage;
}
84.UITableView的Group样式下顶部空白处理:
//分组列表头部空白处理
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 0, 0.1)];
self.tableView.tableHeaderView = view;
85.两种方法删除NSUserDefaults所有记录:
//方法一
NSString *appDomain = [[NSBundle mainBundle] bundleIdentifier];
[[NSUserDefaults standardUserDefaults] removePersistentDomainForName:appDomain];
//方法二
- (void)resetDefaults
{
NSUserDefaults * defs = [NSUserDefaults standardUserDefaults];
NSDictionary * dict = [defs dictionaryRepresentation];
for (id key in dict)
{
[defs removeObjectForKey:key];
}
[defs synchronize];
}
86.防止scrollView手势覆盖侧滑手势:
[scrollView.panGestureRecognizerrequireGestureRecognizerToFail:self.navigationController.interactivePopGestureRecognizer];
87.获取到webview的高度:
CGFloat height = [[self.webView stringByEvaluatingJavaScriptFromString:@"document.body.offsetHeight"] floatValue];
88.WebView长按保存图片:
加一个长按手势，在响应里：
NSString *imgURL = [NSString stringWithFormat:@"document.elementFromPoint(%f, %f).src", touchPoint.x, touchPoint.y];
NSString *urlToSave = [self.webView stringByEvaluatingJavaScriptFromString:imgURL];
89.cell右边标志符的颜色改变:
self.accessoryType = UITableViewCellAccessoryCheckmark;
self.tintColor = [UIColor colorWithRed:140.0/255.0 green:197.0/255.0 blue:66.0/255.0 alpha:1];
90.设置启动页的时间:
[NSThread sleepForTimeInterval:3.0];//设置启动页面时间
91.数组元素按字母排序:
_enStateArr = [_stateDic allKeys];
_enStateArr = [_enStateArr sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2){
NSComparisonResult result = [obj1 compare:obj2];
return result==NSOrderedDescending;
}];
92.四舍五入:
-(float)roundFloat:(float)price
{
return (floorf(price*100 + 0.5))/100;
}
93.红外线感应器的使用（多用于电话接听界面）:
//允许临近检测，物体接近屏幕屏幕变黑且不可操作
[UIDevice currentDevice].proximityMonitoringEnabled = YES;
94.解决ScrollView滑动卡顿的问题:
/** 解决scrollView 滑动卡顿问题 */
[self performSelector:@selector(test1) withObject:nil afterDelay:4 inModes:@[NSDefaultRunLoopMode]];
95.删除重用的cell的所有子视图，从而得到一个没有特殊格式的cell，供其他cell重用:
if (cell == nil)
{
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:identifier];
}
else
{
//删除cell的所有子视图
while ([cell.contentView.subviews lastObject] != nil)
{
[(UIView*)[cell.contentView.subviews lastObject] removeFromSuperview];
}
}
96.iOS单例创建:
+(instancetype)shareManager
{
static User *user = nil;
static dispatch_once_t onceToken;
dispatch_once(&onceToken, ^{
user = [[User alloc] init];
});
return user;
}
97.bounds 和 Frame区别:
先看到下面的代码你肯定就明白了一些：
-(CGRect)frame{
return CGRectMake(self.frame.origin.x,self.frame.origin.y,self.frame.size.width,self.frame.size.height);
}
-(CGRect)bounds{
return CGRectMake(0,0,self.frame.size.width,self.frame.size.height);
}
很明显，bounds的原点是(0,0)点（就是view本身的坐标系统，默认永远都是0，0点，除非人为setbounds），而frame的原点却是任意的（相对于父视图中的坐标位置）。
98.设置键盘在tableView滚动的时候消失掉:
//设置键盘在tableview滚动的时候消失.
tableView.keyboardDismissMode = UIScrollViewKeyboardDismissModeOnDrag;
99.UILabel修改行距,首行缩进:
UILabel修改文字行距,首行缩进
lineSpacing: 行间距
firstLineHeadIndent：首行缩进
font: 字体
textColor: 字体颜色
－(NSDictionary *)settingAttributesWithLineSpacing:(CGFloat)lineSpacing FirstLineHeadIndent:(CGFloat)firstLineHeadIndent Font:(UIFont *)font TextColor:(UIColor *)textColor
{
//分段样式
NSMutableParagraphStyle *paragraphStyle = [[NSMutableParagraphStyle alloc] init];
//行间距
paragraphStyle.lineSpacing = lineSpacing;
//首行缩进
paragraphStyle.firstLineHeadIndent = firstLineHeadIndent;
//富文本样式
NSDictionary *attributeDic = @{
NSFontAttributeName : font,
NSParagraphStyleAttributeName : paragraphStyle,
NSForegroundColorAttributeName : textColor
};
return attributeDic;
}
100.在当前屏幕获取第一响应:
UIWindow * keyWindow = [[UIApplication sharedApplication] keyWindow];
UIView * firstResponder = [keyWindow performSelector:@selector(firstResponder)];
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