iOS开发经验总结

NSMutableAttributedString* attrString = [[NSMutableAttributedString  alloc] initWithString:label.text];    NSMutableParagraphStyle *style = [[NSMutableParagraphStyle alloc] init];
    [style setLineSpacing:20];
    [attrString addAttribute:NSParagraphStyleAttributeName value:style range:NSMakeRange(0, label.text.length)];    label.attributedText = attrString;

// 方法一、// 把参数放进一个数组／字典，直接把数组／字典当成一个参数传过去，具体方法实现的地方再解析这个数组／字典NSArray * array = 
    [NSArray arrayWithObjects: @"first", @"second", nil];
[self performSelector:@selector(fooFirstInput:) withObject: array afterDelay:15.0];// 方法二、// 使用NSInvocationSEL aSelector = NSSelectorFromString(@"doSoming:argument2:");
    NSInteger argument1 = 10;
    NSString *argument2 = @"argument2";    if([self respondsToSelector:aSelector]) {
        NSInvocation *inv = [NSInvocation invocationWithMethodSignature:[self methodSignatureForSelector:aSelector]];
        [inv setSelector:aSelector];
        [inv setTarget:self];
        [inv setArgument:&(argument1) atIndex:2];
        [inv setArgument:&(argument2) atIndex:3];
        [inv performSelector:@selector(invoke) withObject:nil afterDelay:15.0];
    }

NSMutableAttributedString * string = [[NSMutableAttributedString alloc] initWithString:label.text];
[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 = string;

if (CGRectEqualToRect(rect1, rect2)) { // 两个区域相等        // do some
    }    if (CGPointEqualToPoint(point1, point2)) { // 两个点相等        // do some
    }    if (CGSizeEqualToSize(size1, size2)) { // 两个size相等        // do some
    }

 NSDate* date1 = someDate; NSDate* date2 = someOtherDate; NSTimeInterval distanceBetweenDates = [date1 timeIntervalSinceDate:date2]; double secondsInAnHour = 3600;// 除以3600是把秒化成小时，除以60得到结果为相差的分钟数
 NSInteger hoursBetweenDates = distanceBetweenDates / secondsInAnHour;

// 方法一，每个分区只显示一行cell，分区头当作你想要的间距(注意，从数据源数组中取值的时候需要用indexPath.section而不是indexPath.row)- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{    return yourArry.count;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{    return 1;
}
-(CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section
{    return cellSpacingHeight;
}// 方法二，在cell的contentView上加个稍微低一点的view，cell上原本的内容放在你的view上，而不是contentView上，这样能伪造出一个间距来。// 方法三，自定义cell，重写setFrame：方法- (void)setFrame:(CGRect)frame
{
    frame.size.height -= 20;
    [super setFrame:frame];
}

// 加入现在有三张图片分别为animate_1、animate_2、animate_3// 方法一
    imageView.animationImages = @[[UIImage imageNamed:@"animate_1"], [UIImage imageNamed:@"animate_2"], [UIImage imageNamed:@"animate_3"]];
imageView.animationDuration = 1.0;// 方法二
    imageView.image = [UIImage animatedImageNamed:@"animate_" duration:1.0];// 方法二解释下，这个方法会加载animate_为前缀的，后边0-1024，也就是animate_0、animate_1一直到animate_1024

// image分类- (UIImage *)circleImage
{// NO代表透明UIGraphicsBeginImageContextWithOptions(self.size, NO, 1);// 获得上下文CGContextRef ctx = UIGraphicsGetCurrentContext();// 添加一个圆CGRect rect = CGRectMake(0, 0, self.size.width, self.size.height);// 方形变圆形CGContextAddEllipseInRect(ctx, rect);// 裁剪CGContextClip(ctx);// 将图片画上去[self drawInRect:rect];UIImage *image = UIGraphicsGetImageFromCurrentImageContext();UIGraphicsEndImageContext();return image;
}

// 打印字体for (id familyName in [UIFont familyNames]) {    NSLog(@"%@", familyName);    for (id fontName in [UIFont fontNamesForFamilyName:familyName]) NSLog(@"  %@", fontName);
}// 也可以进入这个网址查看 http://iosfonts.com/

NSInteger i = arc4random();

#define ARC4RANDOM_MAX      0x100000000double val = ((double)arc4random() / ARC4RANDOM_MAX);

[[NSNotificationCenter defaultCenter] 
      addObserver:self
      selector:@selector(videoPlayEnd)
      name:AVPlayerItemDidPlayToEndTimeNotification 
      object:nil];

 if (CGRectIntersectsRect(rect1, rect2)) {
}

NSCharacterSet *notDigits = [[NSCharacterSet decimalDigitCharacterSet] invertedSet];    if ([str rangeOfCharacterFromSet:notDigits].location == NSNotFound)
    {      // 是数字
    } else
    {      // 不是数字
    }

- (void)createPDFfromUIView:(UIView*)aView saveToDocumentsWithFileName:(NSString*)aFilename
{    NSMutableData *pdfData = [NSMutableData data];    UIGraphicsBeginPDFContextToData(pdfData, aView.bounds, nil);    UIGraphicsBeginPDFPage();    CGContextRef pdfContext = UIGraphicsGetCurrentContext();
    [aView.layer renderInContext:pdfContext];    UIGraphicsEndPDFContext();    NSArray* documentDirectories = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask,YES);    NSString* documentDirectory = [documentDirectories objectAtIndex:0];    NSString* documentDirectoryFilename = [documentDirectory stringByAppendingPathComponent:aFilename];
    [pdfData writeToFile:documentDirectoryFilename atomically:YES];    NSLog(@"documentDirectoryFileName: %@",documentDirectoryFilename);
}

child.center = [parent convertPoint:parent.center fromView:parent.superview];

- (UIViewController *)backViewController
{    NSInteger myIndex = [self.navigationController.viewControllers indexOfObject:self];    if ( myIndex != 0 && myIndex != NSNotFound ) {        return [self.navigationController.viewControllers objectAtIndex:myIndex-1];
    } else {        return nil;
    }
}

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);NSString *filePath = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"Image.png"];

[UIImagePNGRepresentation(image) writeToFile:filePath atomically:YES];

UIToolbar *keyboardDoneButtonView = [[UIToolbar alloc] init];
[keyboardDoneButtonView sizeToFit];UIBarButtonItem *doneButton = [[UIBarButtonItem alloc] initWithTitle:@"Done"
                                                               style:UIBarButtonItemStyleBordered target:self
                                                              action:@selector(doneClicked:)];
[keyboardDoneButtonView setItems:[NSArray arrayWithObjects:doneButton, nil]];
txtField.inputAccessoryView = keyboardDoneButtonView; 

id copyOfView = 
[NSKeyedUnarchiver unarchiveObjectWithData:[NSKeyedArchiver archivedDataWithRootObject:originalView]];

UIFont *font = [UIFont boldSystemFontOfSize:12];
    UIGraphicsBeginImageContext(image.size);
    [image drawInRect:CGRectMake(0,0,image.size.width,image.size.height)];
    CGRect rect = CGRectMake(point.x, point.y, image.size.width, image.size.height);
    [[UIColor whiteColor] set];
    [text drawInRect:CGRectIntegral(rect) withFont:font]; 
    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

// 如果myView是self.view本身，也会返回yesBOOL isSubView = [myView isDescendantOfView:self.view];

// 方法一、这种方法只适用于iOS8之后，如果是配iOS8之前用方法二
if ([str containsString:otherStr])  NSLog(@"包含");
// 方法二
NSRange range = [str rangeOfString:otherStr];
if (range.location != NSNotFound)  NSLog(@"包含");

// 重写viewDidLayoutSubviews方法-(void)viewDidLayoutSubviews {
   [super viewDidLayoutSubviews];
   [self.collectionView scrollToItemAtIndexPath:indexPath atScrollPosition:UICollectionViewScrollPositionCenteredVertically animated:NO];
}

// 但是据说这种方法会被App Store拒绝(慎用！)UIAlertController *alertVC = [UIAlertController alertControllerWithTitle:@"" message:@"" preferredStyle:UIAlertControllerStyleActionSheet];    NSMutableAttributedString *hogan = [[NSMutableAttributedString alloc] initWithString:@"我是一个大文本"];
    [hogan addAttribute:NSFontAttributeName
                  value:[UIFont systemFontOfSize:30]
                  range:NSMakeRange(4, 1)];
    [hogan addAttribute:NSForegroundColorAttributeName
                  value:[UIColor redColor]
                  range:NSMakeRange(4, 1)];
    [alertVC setValue:hogan forKey:@"attributedTitle"];    UIAlertAction *button = [UIAlertAction actionWithTitle:@"Label text" style:UIAlertActionStyleDefault handler:^(UIAlertAction *action){ }];    UIImage *accessoryImage = [UIImage imageNamed:@"1"];
    [button setValue:accessoryImage forKey:@"image"];
    [alertVC addAction:button];
    [self presentViewController:alertVC animated:YES completion:nil];

CGRect cellRect = [tableView rectForRowAtIndexPath:indexPath];BOOL completelyVisible = CGRectContainsRect(tableView.bounds, cellRect);

NSMutableArray *allViewControllers = [NSMutableArray arrayWithArray:[self.navigationController viewControllers]];for (UIViewController *aViewController in allViewControllers) {    if ([aViewController isKindOfClass:[RequiredViewController class]]) {
        [self.navigationController popToViewController:aViewController animated:NO];
    }
}

// 方法一CATransition *animation = [CATransition animation];
    animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
    animation.type = kCATransitionFade;
    animation.duration = 0.75;
    [self.label.layer addAnimation:animation forKey:@"kCATransitionFade"];    self.label.text = @"New";// 方法二[UIView transitionWithView:self.label
                      duration:0.25f
                       options:UIViewAnimationOptionTransitionCrossDissolve
                    animations:^{                        self.label.text = @"Well done!";

                    } completion:nil];// 方法三[UIView animateWithDuration:1.0
                     animations:^{                         self.label.alpha = 0.0f;                         self.label.text = @"newText";                         self.label.alpha = 1.0f;
                     }];

if ([dic objectForKey:@"yourKey"]) {    NSLog(@"有这个值");
} else {    NSLog(@"没有这个值");
}

UIInterfaceOrientation orientation = [UIApplication sharedApplication].statusBarOrientation;if(orientation == 0) //Default orientation 
    //默认else if(orientation == UIInterfaceOrientationPortrait)    //竖屏else if(orientation == UIInterfaceOrientationLandscapeLeft)    // 左横屏else if(orientation == UIInterfaceOrientationLandscapeRight)    //右横屏

// 方法一、添加UIImage分类- (UIImage *)imageByApplyingAlpha:(CGFloat) alpha {    UIGraphicsBeginImageContextWithOptions(self.size, NO, 0.0f);    CGContextRef ctx = UIGraphicsGetCurrentContext();    CGRect area = 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;
}// 方法二、如果没有奇葩需求，干脆用UIImageView设置透明度UIImageView *imageView = [[UIImageView alloc] initWithImage:[UIImage imageWithName:@"yourImage"]];
imageView.alpha = 0.5;

UITapGestureRecognizer *tap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(webViewClick)];
        tap.delegate = 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，并实现下边的代理方法- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer{    return YES;
}

// 需要导入#import <mach/mach.h>mach_port_t host_port;    mach_msg_type_number_t host_size;    vm_size_t pagesize;

    host_port = mach_host_self();
    host_size = sizeof(vm_statistics_data_t) / sizeof(integer_t);
    host_page_size(host_port, &pagesize);    vm_statistics_data_t vm_stat;    if (host_statistics(host_port, HOST_VM_INFO, (host_info_t)&vm_stat, &host_size) != KERN_SUCCESS) {
        NSLog(@"Failed to fetch vm statistics");
    }    /* Stats in bytes */
    natural_t mem_used = (vm_stat.active_count +
                          vm_stat.inactive_count +
                          vm_stat.wire_count) * pagesize;    natural_t mem_free = vm_stat.free_count * pagesize;    natural_t mem_total = mem_used + mem_free;
    NSLog(@"已用: %u 可用: %u 总共: %u", mem_used, mem_free, mem_total);

// 需要导入#import <CoreLocation/CoreLocation.h>CLLocation *locA = [[CLLocation alloc] initWithLatitude:34 longitude:113];
    CLLocation *locB = [[CLLocation alloc] initWithLatitude:31.05 longitude:121.76];// CLLocationDistance求出的单位为米
    CLLocationDistance distance = [locA distanceFromLocation:locB];

// 打开设置->通用[[UIApplication sharedApplication] openURL:[NSURL URLWithString:@"prefs:root=General"]];// 以下是设置其他界面prefs:root=General&path=Aboutprefs:root=General&path=ACCESSIBILITYprefs:root=AIRPLANE_MODEprefs:root=General&path=AUTOLOCKprefs:root=General&path=USAGE/CELLULAR_USAGEprefs:root=Brightnessprefs:root=Bluetoothprefs:root=General&path=DATE_AND_TIMEprefs:root=FACETIMEprefs:root=Generalprefs:root=General&path=Keyboardprefs:root=CASTLEprefs:root=CASTLE&path=STORAGE_AND_BACKUPprefs:root=General&path=INTERNATIONALprefs:root=LOCATION_SERVICESprefs:root=ACCOUNT_SETTINGSprefs:root=MUSICprefs:root=MUSIC&path=EQprefs:root=MUSIC&path=VolumeLimitprefs:root=General&path=Networkprefs:root=NIKE_PLUS_IPODprefs:root=NOTESprefs:root=NOTIFICATIONS_IDprefs:root=Phoneprefs:root=Photosprefs:root=General&path=ManagedConfigurationListprefs:root=General&path=Resetprefs:root=Sounds&path=Ringtoneprefs:root=Safariprefs:root=General&path=Assistantprefs:root=Soundsprefs:root=General&path=SOFTWARE_UPDATE_LINKprefs:root=STOREprefs:root=TWITTERprefs:root=FACEBOOKprefs:root=General&path=USAGE prefs:root=VIDEOprefs:root=General&path=Network/VPNprefs:root=Wallpaperprefs:root=WIFIprefs:root=INTERNET_TETHERINGprefs:root=Phone&path=Blockedprefs:root=DO_NOT_DISTURB

UITextView *textView = [[UITextView alloc] initWithFrame:CGRectMake(20, 30, 100, 199)];
    textView.backgroundColor = [UIColor redColor];
    [self.view addSubview:textView];    NSString *htmlString = @"<h1>Header</h1><h2>Subheader</h2><p>Some <em>text</em></p>![](http://blogs.babble.com/famecrawler/files/2010/11/mickey_mouse-1097.jpg)";    NSAttributedString *attributedString = [[NSAttributedString alloc] initWithData: [htmlString dataUsingEncoding:NSUnicodeStringEncoding] options: @{ NSDocumentTypeDocumentAttribute: NSHTMLTextDocumentType } documentAttributes: nil error: nil];
    textView.attributedText = attributedString;

-(void)scrollViewDidScroll: (UIScrollView*)scrollView
{    float scrollViewHeight = scrollView.frame.size.height;    float scrollContentSizeHeight = scrollView.contentSize.height;    float scrollOffset = scrollView.contentOffset.y;    if (scrollOffset == 0)
    {        // 滚动到了顶部
    }    else if (scrollOffset + scrollViewHeight == scrollContentSizeHeight)
    {        // 滚动到了底部
    }
}

- (void)setupSlider
{
    UISlider *slider = [[UISlider alloc] init];
    [self.view addSubview:slider];
    [slider addTarget:self action:@selector(sliderAction:) forControlEvents:UIControlEventValueChanged];
    slider.maximumValue = 100;
    slider.minimumValue = 0;
    slider.frame = CGRectMake(200, 20, 100, 30);
}

- (void)sliderAction:(UISlider *)slider
{
    [slider setValue:((int)((slider.value + 2.5) / 5) * 5) animated:NO];
}

[self.textView setSelectedTextRange:[self.textView textRangeFromPosition:self.textView.beginningOfDocument toPosition:self.textView.endOfDocument]]

// 方法一、知道这个控制器所处的导航控制器下标NSMutableArray *navigationArray = [[NSMutableArray alloc] initWithArray: self.navigationController.viewControllers];
[navigationArray removeObjectAtIndex: 2]; 
self.navigationController.viewControllers = navigationArray;// 方法二、知道具体是哪个控制器NSArray* tempVCA = [self.navigationController viewControllers];for(UIViewController *tempVC in tempVCA)
{    if([tempVC isKindOfClass:[urViewControllerClass class]])
    {
        [tempVC removeFromParentViewController];
    }
}

textField.tintColor = [UIColor clearColor];

textField.enablesReturnKeyAutomatically = YES;

// 我们一般用这个方法处理stringByAddingPercentEscapesUsingEncoding但是这个方法好想不会处理／和&这种特殊符号，这种情况就需要用下边这个方法处理@implementation NSString (NSString_Extended)- (NSString *)urlencode {    NSMutableString *output = [NSMutableString string];    const unsigned char *source = (const unsigned char *)[self UTF8String];    int sourceLen = strlen((const char *)source);    for (int i = 0; i < sourceLen; ++i) {        const unsigned char thisChar = source[i];        if (thisChar == ‘ ‘){
            [output appendString:@"+"];
        } else if (thisChar == ‘.‘ || thisChar == ‘-‘ || thisChar == ‘_‘ || thisChar == ‘~‘ || 
                   (thisChar >= ‘a‘ && thisChar <= ‘z‘) ||
                   (thisChar >= ‘A‘ && thisChar <= ‘Z‘) ||
                   (thisChar >= ‘0‘ && thisChar <= ‘9‘)) {
            [output appendFormat:@"%c", thisChar];
        } else {
            [output appendFormat:@"%%%02X", thisChar];
        }
    }    return output;
}

@implementation UILabel (TextRect)- (CGRect)boundingRectForCharacterRange:(NSRange)range
{    NSTextStorage *textStorage = [[NSTextStorage alloc] initWithAttributedString:[self attributedText]];    NSLayoutManager *layoutManager = [[NSLayoutManager alloc] init];
    [textStorage addLayoutManager:layoutManager];    NSTextContainer *textContainer = [[NSTextContainer alloc] initWithSize:[self bounds].size];
    textContainer.lineFragmentPadding = 0;
    [layoutManager addTextContainer:textContainer];    NSRange glyphRange;
    [layoutManager characterRangeForGlyphRange:range actualGlyphRange:&glyphRange];    return [layoutManager boundingRectForGlyphRange:glyphRange inTextContainer:textContainer];
}

NSString *result;    if([[[UIDevice currentDevice] systemVersion] floatValue] > 6.0)
    {
       result = [[NSUUID UUID] UUIDString];
    }    else
    {        CFUUIDRef uuidRef = CFUUIDCreate(NULL);        CFStringRef uuid = CFUUIDCreateString(NULL, uuidRef);        CFRelease(uuidRef);
        result = (__bridge_transfer NSString *)uuid;
    }

#define RADIANS(degrees) (((degrees) * M_PI) / 180.0)- (void)startAnimate {
    view.transform = CGAffineTransformRotate(CGAffineTransformIdentity, RADIANS(-5));

    [UIView animateWithDuration:0.25 delay:0.0 options:(UIViewAnimationOptionAllowUserInteraction | UIViewAnimationOptionRepeat | UIViewAnimationOptionAutoreverse) animations:^ {
                         view.transform = CGAffineTransformRotate(CGAffineTransformIdentity, RADIANS(5));
                     } completion:nil];
}

- (void)stopAnimate {
    [UIView animateWithDuration:0.25 delay:0.0 options:(UIViewAnimationOptionAllowUserInteraction | UIViewAnimationOptionBeginFromCurrentState | UIViewAnimationOptionCurveLinear) animations:^ {
                         view.transform = CGAffineTransformIdentity;
                     } completion:nil];
}

UITextField *textField = [_searchBar valueForKey:@"_searchField"];textField.backgroundColor = [UIColor redColor];

  // 方法一
    [self.textView scrollRangeToVisible:NSMakeRange(0, 0)];   
 // 方法二
    [self.textView setContentOffset:CGPointZero animated:YES];

    // 子类化UITextField，增加insert属性@interface WZBTextField : UITextField@property (nonatomic, assign) UIEdgeInsets insets;@end// 在.m文件重写下列方法- (CGRect)textRectForBounds:(CGRect)bounds {    CGRect paddedRect = UIEdgeInsetsInsetRect(bounds, self.insets);    if (self.rightViewMode == UITextFieldViewModeAlways || self.rightViewMode == UITextFieldViewModeUnlessEditing) {        return [self adjustRectWithWidthRightView:paddedRect];
    }    return paddedRect;
}

- (CGRect)placeholderRectForBounds:(CGRect)bounds {    CGRect paddedRect = UIEdgeInsetsInsetRect(bounds, self.insets);    if (self.rightViewMode == UITextFieldViewModeAlways || self.rightViewMode == UITextFieldViewModeUnlessEditing) {        return [self adjustRectWithWidthRightView:paddedRect];
    }    return paddedRect;
}

- (CGRect)editingRectForBounds:(CGRect)bounds {    CGRect paddedRect = UIEdgeInsetsInsetRect(bounds, self.insets);    if (self.rightViewMode == UITextFieldViewModeAlways || self.rightViewMode == UITextFieldViewModeWhileEditing) {        return [self adjustRectWithWidthRightView:paddedRect];
    }    return paddedRect;
}

- (CGRect)adjustRectWithWidthRightView:(CGRect)bounds {    CGRect paddedRect = bounds;
    paddedRect.size.width -= CGRectGetWidth(self.rightView.frame);    return paddedRect;
}

// 添加事件[slider addTarget:self action:@selector(sliderValurChanged:forEvent:) forControlEvents:UIControlEventValueChanged];// 实现方法- (void)sliderValurChanged:(UISlider*)slider forEvent:(UIEvent*)event {    UITouch *touchEvent = [[event allTouches] anyObject];    switch (touchEvent.phase) {        case UITouchPhaseBegan:            NSLog(@"开始拖动");            break;        case UITouchPhaseMoved:            NSLog(@"正在拖动");            break;        case UITouchPhaseEnded:            NSLog(@"结束拖动");            break;        default:            break;
    }
}

// textField需要设置的textField，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]];
}