【iOS Code #2】iOS常用代码小结

目录

1. 图片拉伸

2. 获取App基本信息

3. 获取渐变颜色图片

4. 图片合成文字

5. 合成图片

6. 旋转图片

7. 获取当前屏幕最顶层的ViewController

---

内容

1. 图片拉伸

/// 拉伸leftCapWidth右边，topCapHeight下边1个像素的位置，其余地方不动
- (UIImage *)stretchableImageWithLeftCapWidth:(NSInteger)leftCapWidth topCapHeight:(NSInteger)topCapHeight;

2. 获取App基本信息

/// 1. 获取设备名称
NSString *deviceName = [[UIDevice currentDevice] name];

/// 2. 获取系统版本号
NSString *sysVersion = [[UIDevice currentDevice] systemVersion];

/// 3. 获取设备唯一标识符
NSString *deviceUUID = [[[UIDevice currentDevice] identifierForVendor] UUIDString];

/// 4. 获取设备的型号
NSString *deviceModel = [[UIDevice currentDevice] model];

NSDictionary *infoDic = [[NSBundle mainBundle] infoDictionary];
// 5. 获取App的版本号
NSString *appVersion = [infoDic objectForKey:@"CFBundleShortVersionString"];
// 6. 获取App的build版本
NSString *appBuildVersion = [infoDic objectForKey:@"CFBundleVersion"];
// 7. 获取App的名称
NSString *appName = [infoDic objectForKey:@"CFBundleDisplayName"];

3. 获取渐变颜色图片

+ (UIImage *)gradientImageWithColors:(NSArray *)colors rect:(CGRect)rect {
    if (!colors.count || CGRectEqualToRect(rect, CGRectZero)) {
        return nil;
    }

    CAGradientLayer *gradientLayer = [CAGradientLayer layer];

    gradientLayer.frame = rect;
    gradientLayer.startPoint = CGPointMake(0, 0);
    gradientLayer.endPoint = CGPointMake(1, 0);
    NSMutableArray *mutColors = [NSMutableArray arrayWithCapacity:colors.count];
    for (UIColor *color in colors) {
        [mutColors addObject:(__bridge id)color.CGColor];
    }
    gradientLayer.colors = mutColors;

    UIGraphicsBeginImageContextWithOptions(gradientLayer.frame.size, gradientLayer.opaque, 0);
    [gradientLayer renderInContext:UIGraphicsGetCurrentContext()];
    UIImage *outputImage = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    NSString * path = NSHomeDirectory();
    NSString * imgPath =[path stringByAppendingString:@"/Documents/222.png"];
    NSLog(@"imgPath %@",imgPath);
    [UIImagePNGRepresentation(outputImage) writeToFile:imgPath atomically:YES];
    return outputImage;
}

3. 图片合成文字

/// 图片合成文字
/// @param text 文字
/// @param fontSize 大小
/// @param textColor 颜色
/// @param textFrame 文字位置
/// @param image 原始图片
/// @param viewFrame 图片所在view的位置
+ (UIImage *)imageWithText:(NSString *)text
                  textFont:(NSInteger)fontSize
                 textColor:(UIColor *)textColor
                 textFrame:(CGRect)textFrame
               originImage:(UIImage *)image
    imageLocationViewFrame:(CGRect)viewFrame {
    
    if (!text)      {  return image;   }
    if (!fontSize)  {  fontSize = 17;   }
    if (!textColor) {  textColor = [UIColor blackColor];   }
    if (!image)     {  return nil;  }
    if (viewFrame.size.height==0 || viewFrame.size.width==0 || textFrame.size.width==0 || textFrame.size.height==0 ){return nil;}

    NSString *mark = text;
    CGFloat height = [mark sizeWithPreferWidth:textFrame.size.width font:[UIFont systemFontOfSize:fontSize]].height; // 此分类方法要导入头文件
    if ((height + textFrame.origin.y) > viewFrame.size.height) { // 文字高度超出父视图的宽度
        height = viewFrame.size.height - textFrame.origin.y;
    }
    
    UIGraphicsBeginImageContext(viewFrame.size);
    [image drawInRect:CGRectMake(0, 0, viewFrame.size.width, viewFrame.size.height)];
    NSDictionary *attr = @{NSFontAttributeName: [UIFont systemFontOfSize:fontSize], NSForegroundColorAttributeName : textColor };
    //位置显示
    [mark drawInRect:CGRectMake(textFrame.origin.x, textFrame.origin.y, textFrame.size.width, height) withAttributes:attr];
    
    UIImage *aimg = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return aimg;
}

5. 合成图片

/// 合成后的图片 (以坐标为参考点，不准确)
/// @param imageArray 图片数组  第一张图片位画布，所以最大
/// @param frameArray 坐标数组
+ (UIImage *)composeImageWithArray:(NSArray<UIImage *> *)imageArray frameArray:(NSArray *)frameArray {
    if (imageArray.count == 0) {  return nil;  }
    if (imageArray.count == 1) {  return imageArray.firstObject;  }
    if (imageArray.count != frameArray.count) {  return nil;  }
    
    __block UIImage *image0;
    [imageArray enumerateObjectsUsingBlock:^(UIImage * _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
        if (obj.size.width == 0) {
            *stop = YES;
            image0 = idx == 0 ? obj : [imageArray objectAtIndex:idx - 1];
        }
    }];
    if (image0) {
        return image0;
    }
    
    NSMutableArray *arrayImages = imageArray.mutableCopy;
    NSMutableArray *arrayFrames = frameArray.mutableCopy;
    
    NSString *string = arrayFrames.firstObject;
    CGRect fristRect = CGRectFromString(string);
    UIImage *img0 = arrayImages.firstObject;
    CGFloat w0 = fristRect.size.width;
    CGFloat h0 = fristRect.size.height;
    // 以第一张的图大小为画布创建上下文
    UIGraphicsBeginImageContext(CGSizeMake(w0, h0));
    [img0 drawInRect:CGRectMake(0, 0, w0, h0)];// 先把第一张图片 画到上下文中
    
    
    for (int i = 1; i < arrayImages.count; i ++) {
        NSString *string2 = [arrayFrames objectAtIndex:i];
        CGRect secondRect = CGRectFromString(string2);
        UIImage *img1 = [arrayImages objectAtIndex:1];
        [img1 drawInRect:secondRect];// 再把小图放在上下文中
    }
    
    UIImage *resultImg = UIGraphicsGetImageFromCurrentImageContext();// 从当前上下文中获得最终图片
    UIGraphicsEndImageContext();// 关闭上下文
    return resultImg;
}

/// 合成后的图片 (以坐标为参考点，准确)
/// @param mainImage 第一张图片位画布
/// @param viewFrame 第一张图片所在View的frame（获取压缩比用）
/// @param imgArray 子图片数组
/// @param frameArray 子图片坐标数组
+ (UIImage *)composeImageOnMainImage:(UIImage * _Nonnull)mainImage
                  mainImageViewFrame:(CGRect)viewFrame
                      subImageArray:(NSArray * _Nonnull)imgArray
                 subImageFrameArray:(NSArray * _Nonnull)frameArray {
    if (!mainImage) {   return nil; }
    if (viewFrame.size.width == 0 || viewFrame.size.height == 0) {   return nil; }
    if (imgArray.count == 0) {  return nil;  }
    if (imgArray.count == 1) {  return imgArray.firstObject;  }
    if (imgArray.count != frameArray.count) {  return nil;  }
    
    // 此处拿到缩放比例
    CGFloat widthScale = mainImage.size.width / viewFrame.size.width;
    CGFloat heightScale = mainImage.size.height / viewFrame.size.height;

    UIGraphicsBeginImageContext(CGSizeMake(mainImage.size.width, mainImage.size.height));
    [mainImage drawInRect:CGRectMake(0, 0, mainImage.size.width, mainImage.size.height)];
    int i = 0;
    for (UIImage *img in imgArray) {
        NSString *string = [frameArray objectAtIndex:i];
        CGRect fristRect = CGRectFromString(string);
        [img drawInRect:CGRectMake(fristRect.origin.x * widthScale, fristRect.origin.y * heightScale, fristRect.size.width, fristRect.size.height)];
        i+=1;
    }
    
    UIImage *resultImg = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
        return resultImg == nil ? mainImage : resultImg;
}

6. 旋转图片

+ (UIImage *)image:(UIImage *)image rotation:(UIImageOrientation)orientation
{
    long double rotate = 0.0;
    CGRect rect;
    float translateX = 0;
    float translateY = 0;
    float scaleX = 1.0;
    float scaleY = 1.0;
    
    switch (orientation) {
        case UIImageOrientationLeft:
            rotate = M_PI_2;
            rect = CGRectMake(0, 0, image.size.height, image.size.width);
            translateX = 0;
            translateY = -rect.size.width;
            scaleY = rect.size.width/rect.size.height;
            scaleX = rect.size.height/rect.size.width;
            break;
        case UIImageOrientationRight:
            rotate = 33 * M_PI_2;
            rect = CGRectMake(0, 0, image.size.height, image.size.width);
            translateX = -rect.size.height;
            translateY = 0;
            scaleY = rect.size.width/rect.size.height;
            scaleX = rect.size.height/rect.size.width;
            break;
        case UIImageOrientationDown:
            rotate = M_PI;
            rect = CGRectMake(0, 0, image.size.width, image.size.height);
            translateX = -rect.size.width;
            translateY = -rect.size.height;
            break;
        default:
            rotate = 0.0;
            rect = CGRectMake(0, 0, image.size.width, image.size.height);
            translateX = 0;
            translateY = 0;
            break;
    }
    
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();
    //做CTM变换
    CGContextTranslateCTM(context, 0.0, rect.size.height);
    CGContextScaleCTM(context, 1.0, -1.0);
    CGContextRotateCTM(context, rotate);
    CGContextTranslateCTM(context, translateX, translateY);
    
    CGContextScaleCTM(context, scaleX, scaleY);
    //绘制图片
    CGContextDrawImage(context, CGRectMake(0, 0, rect.size.width, rect.size.height), image.CGImage);
    
    UIImage *newPic = UIGraphicsGetImageFromCurrentImageContext();
    
    return newPic;
}

7. 获取当前屏幕最顶层的ViewController

// UIViewController+TopViewController.h

+ (UIViewController * )topViewController {
    UIViewController *resultVC;
    resultVC = [self recursiveTopViewController:[[UIApplication sharedApplication].keyWindow rootViewController]];
    while (resultVC.presentedViewController) {
        resultVC = [self recursiveTopViewController:resultVC.presentedViewController];
    }
    return resultVC;
}

+ (UIViewController * )recursiveTopViewController:(UIViewController *)vc {
    if ([vc isKindOfClass:[UINavigationController class]]) {
        return [self recursiveTopViewController:[(UINavigationController *)vc topViewController]];
    } else if ([vc isKindOfClass:[UITabBarController class]]) {
        return [self recursiveTopViewController:[(UITabBarController *)vc selectedViewController]];
    } else {
        return vc;
    }
    return nil;
}

使用

UIViewController *vc = [UIViewController toViewController];