iOS开发改变光标颜色苹果怎么设置光标变圆

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kekenai 2023-09-28 10:28:45

文章标签 iOS开发改变光标颜色 hive html 加载 文章分类 iOS 移动开发

链接：http://www.jianshu.com/p/9fcd37c0ea05

7、播放一张张连续的图片

// 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

8、加载gif图片

推荐使用这个框架 FLAnimatedImage

9、防止离屏渲染为image添加圆角

// 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;
}

16、将一个view保存为pdf格式

- (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);
}

20、键盘上方增加工具栏

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;

21、copy一个view

因为UIView没有实现copy协议，因此找不到copyWithZone方法，使用copy的时候导致崩溃
但是我们可以通过归档再解档实现copy，这相当于对视图进行了一次深拷贝，代码如下

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

22、在image上绘制文字并生成新的image

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();

23、判断一个view是否为另一个view的子视图

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

25、UICollectionView自动滚动到某行

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

27、判断某一行的cell是否已经显示

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

29、动画修改label上的文字

// 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;
                     }];

32、设置UIImage的透明度

// 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;

33、Attempt to mutate immutable object with insertString:atIndex:

这个错是因为你拿字符串调用insertString:atIndex:方法的时候，调用对象不是NSMutableString，应该先转成这个类型再调用

34、UIWebView添加单击手势不响应

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;
}

38、在UITextView中显示html文本

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;

39、监听scrollView是否滚动到了顶部／底部

-(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
    }
}

41、选中textField或者textView所有文本(我这里以textView为例)

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

42、从导航控制器中删除某个控制器

// 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];
    }
}

43、隐藏UITextView/UITextField光标

textField.tintColor = [UIColor clearColor];

44、当UITextView/UITextField中没有文字时，禁用回车键

textField.enablesReturnKeyAutomatically = YES;

48、仿苹果抖动动画

#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];
}

49、修改UISearBar内部背景颜色

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

50、UITextView滚动到顶部

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

53、UITextField文字周围增加边距

// 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;
}

54、监听UISlider拖动状态

// 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;
    }
}

55、设置UITextField光标位置

// 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]];
}

56、去除webView底部黑色

[webView setBackgroundColor:[UIColor clearColor]];
    [webView setOpaque:NO];

    for (UIView *v1 in [webView subviews])
    {
        if ([v1 isKindOfClass:[UIScrollView class]])
        {
            for (UIView *v2 in v1.subviews)
            {
                if ([v2 isKindOfClass:[UIImageView class]])
                {
                    v2.hidden = YES;
                }
            }
        }
    }

57、获取collectionViewCell在屏幕中的frame

UICollectionViewLayoutAttributes *attributes = [collectionView layoutAttributesForItemAtIndexPath:indexPath];
CGRect cellRect = attributes.frame;
CGRect cellFrameInSuperview = [collectionView convertRect:cellRect toView:[cv superview]];

59、解决当UIScrollView上有UIButton的时候，触摸到button滑动不了的问题

// 子类化UIScrollView，并重写以下方法
- (instancetype)initWithFrame:(CGRect)frame {
    if (self = [super initWithFrame:frame]) {
        self.delaysContentTouches = NO;
    }

    return self;
}

- (BOOL)touchesShouldCancelInContentView:(UIView *)view {
    if ([view isKindOfClass:UIButton.class]) {
        return YES;
    }

    return [super touchesShouldCancelInContentView:view];
}

60、UITextView中的文字添加阴影效果

- (void)setTextLayer:(UITextView *)textView color:(UIColor *)color
{
    CALayer *textLayer = ((CALayer *)[textView.layer.sublayers objectAtIndex:0]);
    textLayer.shadowColor = color.CGColor;
    textLayer.shadowOffset = CGSizeMake(0.0f, 1.0f);
    textLayer.shadowOpacity = 1.0f;
    textLayer.shadowRadius = 1.0f;
}

66、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];
    }
}

67、页面跳转实现翻转动画

// modal方式
    TestViewController *vc = [[TestViewController alloc] init];
    vc.view.backgroundColor = [UIColor redColor];
    vc.modalTransitionStyle = UIModalTransitionStyleCoverVertical;
    [self presentViewController:vc animated:YES completion:nil];

// push方式
    TestViewController *vc = [[TestViewController alloc] init];
    vc.view.backgroundColor = [UIColor redColor];
    [UIView beginAnimations:@"View Flip" context:nil];
    [UIView setAnimationDuration:0.80];
    [UIView setAnimationCurve:UIViewAnimationCurveEaseInOut];
    [UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight forView:self.navigationController.view cache:NO];
    [self.navigationController pushViewController:vc animated:YES];
    [UIView commitAnimations];

68、tableView实现无限滚动

- (void)scrollViewDidScroll:(UIScrollView *)scrollView
{
    CGFloat actualPosition = scrollView.contentOffset.y;
    CGFloat contentHeight = scrollView.contentSize.height - scrollView.frame.size.height;
    if (actualPosition >= contentHeight) {
        [self.dataArr addObjectsFromArray:self.dataArr];
        [self.tableView reloadData];
    }
}

69、代码方式调整屏幕亮度

// brightness属性值在0-1之间，0代表最小亮度，1代表最大亮度
[[UIScreen mainScreen] setBrightness:0.5];

72、删除UISearchBar系统默认边框

// 方法一
    searchBar.searchBarStyle = UISearchBarStyleMinimal;

    // 方法二
    [searchBar setBackgroundImage:[[UIImage alloc]init]];

    // 方法三
    searchBar.barTintColor = [UIColor whiteColor];

73、为UICollectionViewCell设置圆角和阴影

cell.contentView.layer.cornerRadius = 2.0f;
cell.contentView.layer.borderWidth = 1.0f;
cell.contentView.layer.borderColor = [UIColor clearColor].CGColor;
cell.contentView.layer.masksToBounds = YES;

cell.layer.shadowColor = [UIColor lightGrayColor].CGColor;
cell.layer.shadowOffset = CGSizeMake(0, 2.0f);
cell.layer.shadowRadius = 2.0f;
cell.layer.shadowOpacity = 1.0f;
cell.layer.masksToBounds = NO;
cell.layer.shadowPath = [UIBezierPath bezierPathWithRoundedRect:cell.bounds cornerRadius:cell.contentView.layer.cornerRadius].CGPath;

74、让正在滑动的scrollView停止滚动(不是禁止，而是暂时停止滚动)

[scrollView setContentOffset:scrollView.contentOffset animated:NO];

77、如何防止添加多个NSNotification观察者？

// 解决方案就是添加观察者之前先移除下这个观察者
[[NSNotificationCenter defaultCenter] removeObserver:observer name:name object:object];
        [[NSNotificationCenter defaultCenter] addObserver:observer selector:selector name:name object:object];

78、将一个xib添加到另外一个xib上

// 假设你的自定义view名字为CustomView，你需要在CustomView.m中重写 `- (instancetype)initWithCoder:(NSCoder *)aDecoder` 方法，代码如下：
- (instancetype)initWithCoder:(NSCoder *)aDecoder {
    if ((self = [super initWithCoder:aDecoder])) {
        [self addSubview:[[[NSBundle mainBundle] loadNibNamed:@"CustomView" owner:self options:nil] objectAtIndex:0]];
    }
    return self;
}

将一个xib添加到另外一个xib上.png

81、获取字符串中的数字

- (NSString *)getNumberFromStr:(NSString *)str
{
    NSCharacterSet *nonDigitCharacterSet = [[NSCharacterSet decimalDigitCharacterSet] invertedSet];
    return [[str componentsSeparatedByCharactersInSet:nonDigitCharacterSet] componentsJoinedByString:@""];
}

    NSLog(@"%@", [self getNumberFromStr:@"a0b0c1d2e3f4fda8fa8fad9fsad23"]); // 00123488923

82、为UIView的某个方向添加边框

// 添加UIView分类

// UIView+WZB.h
#import <UIKit/UIKit.h>


/**
 边框方向

 - WZBBorderDirectionTop: 顶部
 - WZBBorderDirectionLeft: 左边
 - WZBBorderDirectionBottom: 底部
 - WZBBorderDirectionRight: 右边
 */
typedef NS_ENUM(NSInteger, WZBBorderDirectionType) {
    WZBBorderDirectionTop = 0,
    WZBBorderDirectionLeft,
    WZBBorderDirectionBottom,
    WZBBorderDirectionRight
};

@interface UIView (WZB)


/**
 为UIView的某个方向添加边框

 @param direction 边框方向
 @param color 边框颜色
 @param width 边框宽度
 */
- (void)wzb_addBorder:(WZBBorderDirectionType)direction color:(UIColor *)color width:(CGFloat)width;

@end

// UIView+WZB.m
#import "UIView+WZB.h"

@implementation UIView (WZB)

- (void)wzb_addBorder:(WZBBorderDirectionType)direction color:(UIColor *)color width:(CGFloat)width
{
    CALayer *border = [CALayer layer];
    border.backgroundColor = color.CGColor;
    switch (direction) {
        case WZBBorderDirectionTop:
        {
            border.frame = CGRectMake(0.0f, 0.0f, self.bounds.size.width, width);
        }
            break;
        case WZBBorderDirectionLeft:
        {
            border.frame = CGRectMake(0.0f, 0.0f, width, self.bounds.size.height);
        }
            break;
        case WZBBorderDirectionBottom:
        {
            border.frame = CGRectMake(0.0f, self.bounds.size.height - width, self.bounds.size.width, width);
        }
            break;
        case WZBBorderDirectionRight:
        {
            border.frame = CGRectMake(self.bounds.size.width - width, 0, width, self.bounds.size.height);
        }
            break;

        default:
            break;
    }
    [self.layer addSublayer:border];
}

83、通过属性设置UISwitch、UIProgressView等控件的宽高

mySwitch.transform = CGAffineTransformMakeScale(5.0f, 5.0f);

progressView.transform = CGAffineTransformMakeScale(5.0f, 5.0f);

84、自动搜索功能，用户连续输入的时候不搜索，用户停止输入的时候自动搜索(我这里设置的是0.5s，可根据需求更改)

// 输入框文字改变的时候调用
-(void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText{
    // 先取消调用搜索方法
    [NSObject cancelPreviousPerformRequestsWithTarget:self selector:@selector(searchNewResult) object:nil];
    // 0.5秒后调用搜索方法
    [self performSelector:@selector(searchNewResult) withObject:nil afterDelay:0.5];
}

85、修改UISearchBar的占位文字颜色

// 方法一（推荐使用）
    UITextField *searchField = [searchBar valueForKey:@"_searchField"];
    [searchField setValue:[UIColor blueColor] forKeyPath:@"_placeholderLabel.textColor"];

86、某个界面多个事件同时响应引起的问题(比如，两个button同时按push到新界面，两个都会响应，可能导致push重叠)

// UIView有个属性叫做exclusiveTouch，设置为YES后，其响应事件会和其他view互斥(有其他view事件响应的时候点击它不起作用)
view.exclusiveTouch = YES;

// 一个一个设置太麻烦了，可以全局设置
[[UIView appearance] setExclusiveTouch:YES];

// 或者只设置button
[[UIButton appearance] setExclusiveTouch:YES];

87、修改tabBar的frame

// 子类化UITabBarViewController，我这里以修改tabBar高度为例，重写viewWillLayoutSubviews方法
#import "WZBTabBarViewController.h"

@interface WZBTabBarViewController ()

@end

@implementation WZBTabBarViewController
- (void)viewWillLayoutSubviews {

    CGRect tabFrame = self.tabBar.frame;
    tabFrame.size.height = 100;
    tabFrame.origin.y = self.view.frame.size.height - 100;
    self.tabBar.frame = tabFrame;
}
@end

88、修改键盘背景颜色

// 设置某个键盘颜色
    textField.keyboardAppearance = UIKeyboardAppearanceAlert;

// 设置工程中所有键盘颜色
[[UITextField appearance] setKeyboardAppearance:UIKeyboardAppearanceAlert];

92、设置UIButton高亮时的背景颜色

// 方法一、子类化UIButton，重写setHighlighted:方法，代码如下
#import "WZBButton.h"

@implementation WZBButton

- (void)setHighlighted:(BOOL)highlighted {
    [super setHighlighted:highlighted];

    UIColor *normalColor = [UIColor greenColor];
    UIColor *highlightedColor = [UIColor redColor];
    self.backgroundColor = highlighted ? highlightedColor : normalColor;

}

// 方法二、利用setBackgroundImage:forState:方法
[button setBackgroundImage:[self imageWithColor:[UIColor blueColor]] forState:UIControlStateHighlighted];

- (UIImage *)imageWithColor:(UIColor *)color {
    CGRect rect = CGRectMake(0.0f, 0.0f, 1.0f, 1.0f);
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();

    CGContextSetFillColorWithColor(context, [color CGColor]);
    CGContextFillRect(context, rect);

    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();

    return image;
}

93、关于图片拉伸

推荐看这个博客，讲的很详细

96、让push跳转动画像modal跳转动画那样效果(从下往上推上来)

- (void)push
{
TestViewController *vc = [[TestViewController alloc] init];
    vc.view.backgroundColor = [UIColor redColor];
    CATransition* transition = [CATransition animation];
    transition.duration = 0.4f;
    transition.type = kCATransitionMoveIn;
    transition.subtype = kCATransitionFromTop;
    [self.navigationController.view.layer addAnimation:transition forKey:kCATransition];
    [self.navigationController pushViewController:vc animated:NO];
}

- (void)pop
{
CATransition* transition = [CATransition animation];
    transition.duration = 0.4f;
    transition.type = kCATransitionReveal;
    transition.subtype = kCATransitionFromBottom;
    [self.navigationController.view.layer addAnimation:transition forKey:kCATransition];
    [self.navigationController popViewControllerAnimated:NO];
}

97、上传图片太大，压缩图片

-(UIImage *)resizeImage:(UIImage *)image
{
    float actualHeight = image.size.height;
    float actualWidth = image.size.width;
    float maxHeight = 300.0;
    float maxWidth = 400.0;
    float imgRatio = actualWidth/actualHeight;
    float maxRatio = maxWidth/maxHeight;
    float compressionQuality = 0.5;//50 percent compression

    if (actualHeight > maxHeight || actualWidth > maxWidth)
    {
        if(imgRatio < maxRatio)
        {
            //adjust width according to maxHeight
            imgRatio = maxHeight / actualHeight;
            actualWidth = imgRatio * actualWidth;
            actualHeight = maxHeight;
        }
        else if(imgRatio > maxRatio)
        {
            //adjust height according to maxWidth
            imgRatio = maxWidth / actualWidth;
            actualHeight = imgRatio * actualHeight;
            actualWidth = maxWidth;
        }
        else
        {
            actualHeight = maxHeight;
            actualWidth = maxWidth;
        }
    }

    CGRect rect = CGRectMake(0.0, 0.0, actualWidth, actualHeight);
    UIGraphicsBeginImageContext(rect.size);
    [image drawInRect:rect];
    UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
    NSData *imageData = UIImageJPEGRepresentation(img, compressionQuality);
    UIGraphicsEndImageContext();

    return [UIImage imageWithData:imageData];

}

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85、修改UISearchBar的占位文字颜色

86、某个界面多个事件同时响应引起的问题(比如，两个button同时按push到新界面，两个都会响应，可能导致push重叠)

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88、修改键盘背景颜色

92、设置UIButton高亮时的背景颜色

93、关于图片拉伸

96、让push跳转动画像modal跳转动画那样效果(从下往上推上来)

97、上传图片太大，压缩图片

51CTO博客

iOS开发改变光标颜色苹果怎么设置光标变圆

iOS开发改变光标颜色苹果怎么设置光标变圆