IOS 开发常见功能代码集
2017-06-28 本文已影响48人
leonardni
文章结构
- 动画切换window的根控制器
- 打开APP权限设置
- 给一个view截图
- 设置navigationBar上的title颜色和大小
- 颜色转图片
- 自定义NSLog
- 修改textField的placeholder的字体颜色、大小
- 控制屏幕旋转，在控制器中写
11.长按复制功能
12.判断图片类型
13.获取手机和app信息
17.移除字符串中的空格和换行- 获取一个视频的第一帧图片
19.获取视频的时长
20.当tableView占不满一屏时，去除下边多余的单元格
21.从NSURL中拿到链接字符串
22.删除某个view所有的子视图- 删除NSUserDefaults所有记录
- 自定义cell选中背景颜色
- UIview设置渐变色
27.layoutSubviews方法什么时候调用？- 摇一摇功能
- UIImage和base64互转
- 为一个view添加虚线边框
- UITextView中打开或禁用复制，剪切，选择，全选等功能
- 判断当前控制器是否显示
1. 动画切换window的根控制器
// options是动画选项
[UIView transitionWithView:[UIApplication sharedApplication].keyWindow
duration:0.5f options:UIViewAnimationOptionTransitionCrossDissolve animations:^{
BOOL oldState = [UIView areAnimationsEnabled];
[UIView setAnimationsEnabled:NO];
[UIApplication sharedApplication].keyWindow.rootViewController = [RootViewController new];
[UIView setAnimationsEnabled:oldState];
} completion:^(BOOL finished) {
}];
2. 打开APP权限设置
// 跳进app设置
if (UIApplicationOpenSettingsURLString != NULL) {
NSURL *url = [NSURL URLWithString:UIApplicationOpenSettingsURLString];
[[UIApplication sharedApplication] openURL:url];
}
3. 给一个view截图
UIGraphicsBeginImageContextWithOptions(view.bounds.size, YES, 0.0);
[view.layer renderInContext:UIGraphicsGetCurrentContext()];
UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
4. 设置navigationBar上的title颜色和大小
[self.navigationController.navigationBar setTitleTextAttributes:@{NSForegroundColorAttributeName : [UIColor youColor], NSFontAttributeName : [UIFont systemFontOfSize:15]}];
5. 颜色转图片
+ (UIImage *)cl_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;
}
6. 自定义NSLog
#ifdef DEBUG
#define NSLog(fmt, ...) NSLog((@"%s [Line %d] " fmt), __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__)
#else
#define NSLog(...)
#endif
7. 随机颜色
+ (UIColor *)RandomColor {
NSInteger aRedValue = arc4random() % 255;
NSInteger aGreenValue = arc4random() % 255;
NSInteger aBlueValue = arc4random() % 255;
UIColor *randColor = [UIColor colorWithRed:aRedValue / 255.0f green:aGreenValue / 255.0f blue:aBlueValue / 255.0f alpha:1.0f];
return randColor;
}
8. 修改textField的placeholder的字体颜色、大小
[textField setValue:[UIColor redColor] forKeyPath:@"_placeholderLabel.textColor"];
[textField setValue:[UIFont boldSystemFontOfSize:16] forKeyPath:@"_placeholderLabel.font"];
9.统一收起键盘
[[[UIApplication sharedApplication] keyWindow] endEditing:YES];
10. 控制屏幕旋转，在控制器中写
/** 是否支持自动转屏 */
- (BOOL)shouldAutorotate {
return YES;
}
/** 支持哪些屏幕方向 */
- (UIInterfaceOrientationMask)supportedInterfaceOrientations {
return UIInterfaceOrientationMaskLandscapeLeft | UIInterfaceOrientationMaskLandscapeRight;
}
/** 默认的屏幕方向（当前ViewController必须是通过模态出来的UIViewController（模态带导航的无效）方式展现出来的，才会调用这个方法） */
- (UIInterfaceOrientation)preferredInterfaceOrientationForPresentation {
return UIInterfaceOrientationLandscapeLeft | UIInterfaceOrientationLandscapeRight;
}
11.长按复制功能
- (void)viewDidLoad
{
[self.view addGestureRecognizer:[[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(pasteBoard:)]];
}
- (void)pasteBoard:(UILongPressGestureRecognizer *)longPress {
if (longPress.state == UIGestureRecognizerStateBegan) {
UIPasteboard *pasteboard = [UIPasteboard generalPasteboard];
pasteboard.string = @"需要复制的文本";
}
}
12.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;
}
13.获取手机和app信息
NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
CFShow(infoDictionary);
// app名称
NSString *app_Name = [infoDictionary objectForKey:@"CFBundleDisplayName"];
// app版本
NSString *app_Version = [infoDictionary objectForKey:@"CFBundleShortVersionString"];
// app build版本
NSString *app_build = [infoDictionary objectForKey:@"CFBundleVersion"];
//手机序列号
NSString* identifierNumber = [[UIDevice currentDevice] uniqueIdentifier];
NSLog(@"手机序列号: %@",identifierNumber);
//手机别名： 用户定义的名称
NSString* userPhoneName = [[UIDevice currentDevice] name];
NSLog(@"手机别名: %@", userPhoneName);
//设备名称
NSString* deviceName = [[UIDevice currentDevice] systemName];
NSLog(@"设备名称: %@",deviceName );
//手机系统版本
NSString* phoneVersion = [[UIDevice currentDevice] systemVersion];
NSLog(@"手机系统版本: %@", phoneVersion);
//手机型号
NSString* phoneModel = [[UIDevice currentDevice] model];
NSLog(@"手机型号: %@",phoneModel );
//地方型号 （国际化区域名称）
NSString* localPhoneModel = [[UIDevice currentDevice] localizedModel];
NSLog(@"国际化区域名称: %@",localPhoneModel );
NSDictionary *infoDictionary = [[NSBundle mainBundle] infoDictionary];
// 当前应用名称
NSString *appCurName = [infoDictionary objectForKey:@"CFBundleDisplayName"];
NSLog(@"当前应用名称：%@",appCurName);
// 当前应用软件版本 比如：1.0.1
NSString *appCurVersion = [infoDictionary objectForKey:@"CFBundleShortVersionString"];
NSLog(@"当前应用软件版本:%@",appCurVersion);
// 当前应用版本号码 int类型
NSString *appCurVersionNum = [infoDictionary objectForKey:@"CFBundleVersion"];
NSLog(@"当前应用版本号码：%@",appCurVersionNum);
14. image圆角
- (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;
}
15. 导入自定义字体库
- 找到你想用的字体的 ttf 格式，拖入工程
- 在工程的plist中增加一行数组，“Fonts provided by application”
- 为这个key添加一个item，value为你刚才导入的ttf文件名
- 直接使用即可：label.font = [UIFont fontWithName:@"你刚才导入的ttf文件名" size:20.0]；
16. 获得灰度图
+ (UIImage*)covertToGrayImageFromImage:(UIImage*)sourceImage
{
int width = sourceImage.size.width;
int height = sourceImage.size.height;
CGColorSpaceRef colorSpace = CGColorSpaceCreateDeviceGray();
CGContextRef context = CGBitmapContextCreate (nil,width,height,8,0,colorSpace,kCGImageAlphaNone);
CGColorSpaceRelease(colorSpace);
if (context == NULL) {
return nil;
}
CGContextDrawImage(context,CGRectMake(0, 0, width, height), sourceImage.CGImage);
CGImageRef contextRef = CGBitmapContextCreateImage(context);
UIImage *grayImage = [UIImage imageWithCGImage:contextRef];
CGContextRelease(context);
CGImageRelease(contextRef);
return grayImage;
}
17.移除字符串中的空格和换行
+ (NSString *)removeSpaceAndNewline:(NSString *)str {
NSString *temp = [str stringByReplacingOccurrencesOfString:@" " withString:@""];
temp = [temp stringByReplacingOccurrencesOfString:@"\r" withString:@""];
temp = [temp stringByReplacingOccurrencesOfString:@"\n" withString:@""];
return temp;
}
18. 获取一个视频的第一帧图片
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;
19.获取视频的时长
+ (NSInteger)getVideoTimeByUrlString:(NSString *)urlString {
NSURL *videoUrl = [NSURL URLWithString:urlString];
AVURLAsset *avUrl = [AVURLAsset assetWithURL:videoUrl];
CMTime time = [avUrl duration];
int seconds = ceil(time.value/time.timescale);
return seconds;
}
20.当tableView占不满一屏时，去除下边多余的单元格
self.tableView.tableHeaderView = [UIView new];
self.tableView.tableFooterView = [UIView new];
21.从NSURL中拿到链接字符串
NSString *urlString = myURL.absoluteString;
22.删除某个view所有的子视图
[[someView subviews]
makeObjectsPerformSelector:@selector(removeFromSuperview)];
23. 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];
}
// 方法三
[[NSUserDefaults standardUserDefaults] setPersistentDomain:[NSDictionary dictionary] forName:[[NSBundle mainBundle] bundleIdentifier]];
24.禁用系统滑动返回功能
- (void)viewDidAppear:(BOOL)animated
{
[super viewDidAppear:animated];
if ([self.navigationController respondsToSelector:@selector(interactivePopGestureRecognizer)]) {self.navigationController.interactivePopGestureRecognizer.delegate = self;
}
}
- (void)viewWillDisappear:(BOOL)animated {
[super viewWillDisappear:animated];
if ([self.navigationController respondsToSelector:@selector(interactivePopGestureRecognizer)]) {self.navigationController.interactivePopGestureRecognizer.delegate = nil;
}
}
- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
return NO;
}
25. 自定义cell选中背景颜色
UIView *bgColorView = [[UIView alloc] init];
bgColorView.backgroundColor = [UIColor redColor];
[cell setSelectedBackgroundView:bgColorView];
26. UIview设置渐变色
UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 100)];
[self.view addSubview:view];
CAGradientLayer *gradient = [CAGradientLayer layer];
gradient.frame = view.bounds;
gradient.colors = [NSArray arrayWithObjects:(id)[[UIColor blackColor] CGColor], (id)[[UIColor whiteColor] CGColor], nil];
[view.layer insertSublayer:gradient atIndex:0];
27.layoutSubviews方法什么时候调用？
1、init方法不会调用
2、addSubview方法等时候会调用
3、bounds改变的时候调用
4、scrollView滚动的时候会调用scrollView的layoutSubviews方法(所以不建议在scrollView的layoutSubviews方法中做复杂逻辑)
5、旋转设备的时候调用
6、子视图被移除的时候调用
参考请看：http://blog.logichigh.com/2011/03/16/when-does-layoutsubviews-get-called/
28. 摇一摇功能
1、打开摇一摇功能
[UIApplication sharedApplication].applicationSupportsShakeToEdit = YES;
2、让需要摇动的控制器成为第一响应者
[self becomeFirstResponder];
3、实现以下方法
// 开始摇动
- (void)motionBegan:(UIEventSubtype)motion withEvent:(UIEvent *)event
// 取消摇动
- (void)motionCancelled:(UIEventSubtype)motion withEvent:(UIEvent *)event
// 摇动结束
- (void)motionEnded:(UIEventSubtype)motion withEvent:(UIEvent *)event
29. 修改UISegmentedControl的字体样式
[segment setTitleTextAttributes:@{NSFontAttributeName : [UIFont systemFontOfSize:15.0f]} forState:UIControlStateNormal];
30. UIImage和base64互转
// view分类方法
- (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];
}
31. 为一个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];
32. 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];
}
33. 判断当前控制器是否显示
- (BOOL)isCurrentViewOnScreen {
return self.isViewLoaded && self.view.window;
}
