Add watermark text on IOS images (watermark text on Weibo images) and ios watermarks

Add watermark text on IOS images (watermark text on Weibo) and ios watermark

Create a category (you can go to Baidu if you don't know how to create it ).

Class Object. h file name: UIImage + watermark

# Import <UIKit/UIKit. h>

@ Interface UIImage (watermark)

// Define a method

-(UIImage *) watermarkImage :( NSString *) text;

@ End

. M file implementation

# Import "UIImage + watermark. h"

@ Implementation UIImage (watermark)

-(UIImage *) watermarkImage :( NSString *) text {

// 1. Obtain the context

UIGraphicsBeginImageContext (self. size );

// 2. Draw an image

[SelfdrawInRect: CGRectMake (0, 0, self. size. width, self. size. height)];

// 3. Draw watermark text

CGRect rect = CGRectMake (0, self. size. height-20, self. size. width, 20 );

NSMutableParagraphStyle * style = [[NSMutableParagraphStyledefaultParagraphStyle] mutableCopy];

Style. alignment = NSTextAlignmentCenter;

// Text attributes

NSDictionary * dic = @{

NSFontAttributeName: [UIFontsystemFontOfSize: 13],

NSParagraphStyleAttributeName: style,

NSForegroundColorAttributeName: [UIColorwhiteColor]

};

// Draw the text

[Text drawInRect: rectwithAttributes: dic];

// 4. Obtain the drawn Image

UIImage * watermarkImage = UIGraphicsGetImageFromCurrentImageContext ();

// 5. Draw the ending Image

UIGraphicsEndImageContext ();

Return watermarkImage;

}

@ End

Then add a UIImageView import category (UIImage + watermark) file to the viewController view.

# Import "ViewController. h"

# Import "UIImage + watermark. h"

@ Interface ViewController ()

@ End

@ Implementation ViewController

-(Void) viewDidLoad {

[SuperviewDidLoad];

UIImage * image = [UIImageimageNamed: @ "baymax.jpg"];

// Call the objective method implementation function

UIImage * img = [image watermarkImage: @ "@ "];

UIImageView * imageView = [[UIImageViewalloc] initWithImage: img];

// ImageView. frame = self. view. bounds;

[Self. viewaddSubview: imageView];

}

-(Void) didReceiveMemoryWarning {

[SuperdidReceiveMemoryWarning];

// Dispose of any resources that can be recreated.

}

@ End