Avoid white background in UIImageView

Question

I have .png images, and my backgrounds are white. I wanted a quick solution to transform the white background in a transparent background (code solution) as the app bg is grey and not white. I already tried CSS (pixate) but it doesn't work.

-(void)getImageFromeRequestedUrl:(NSString*)urlRequested {
NSString *userName = @"userName";
NSString *password = @"passWord";
NSMutableURLRequest *urlRequest = [[NSMutableURLRequest alloc] initWithURL:[NSURL URLWithString:urlRequested]];
NSString *basicAuthCredentials = [NSString stringWithFormat:@"%@:%@", userName, password];
NSString *authValue = [NSString stringWithFormat:@"Basic %@", AFBase64EncodedStringFromString(basicAuthCredentials)];
[urlRequest setValue:authValue forHTTPHeaderField:@"Authorization"];
AFHTTPRequestOperation *requestOperation = [[AFHTTPRequestOperation alloc] initWithRequest:urlRequest];
requestOperation.responseSerializer = [AFImageResponseSerializer serializer];
[requestOperation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
    NSLog(@"Response: %@", responseObject);
    self.image.image = responseObject;
    self.image.frame = CGRectMake(0, 0, 300, 300);
    self.image.center = self.image.superview.center;
    self.image.backgroundColor = [UIColor clearColor];

} failure:^(AFHTTPRequestOperation *operation, NSError *error) {
    NSLog(@"Image error: %@", error);
}];
[requestOperation start];
}

I'm confused why you would try setting css pixate when css has absolutely nothing to do with objective-c and there is no way of setting any css. That one line confuses the hell out of me and gives the impression there is something you're not telling us. — Popeye, Oct 07 '14 at 14:08
possible duplicate of [UIKit. How to set Transparent color?](http://stackoverflow.com/questions/985694/uikit-how-to-set-transparent-color) — Cy-4AH, Oct 07 '14 at 14:09
@Popeye I'm using Pixate, which is a Framework that let you use CSS in iOs ! — Nicolas Charvoz, Oct 07 '14 at 14:14
You should be telling us that. That is some vital information that we would need to know. Just putting CSS (Pixate) means nothing to some of us. — Popeye, Oct 07 '14 at 14:15

score 1 · Answer 1 · edited Jun 20 '20 at 09:12

1

Issue

Your imageView backgroundColor I think is white, because is white by default. Also when you open your transparent .png images in a photoViewer their background looks white, but it's not like that. If you have a tool like PhotoShop, you can open it and see the difference.

Solution

To deal with transparent png images in UIImageView you need to set the imageView background color to transparent.

The clear color makes the imageView background transparent:

UIImageView *imageView = [[UIImageView alloc] init];
imageView.backgroundColor = [UIColor clearColor];

Also try to change your view the background color to another color than white, if your white part changes color, then the image is transparent, and the configurations are made ok.

edited Jun 20 '20 at 09:12

Community

1
1

answered Oct 07 '14 at 14:02

E-Riddie

14,660
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doesn't change anything. – Nicolas Charvoz Oct 07 '14 at 14:07
Now you don't have transparent images, and you want to make it by code? Then this question needs to be somewhere else, where you need to make extra algorithms, or read how to lose the background of a png image. I use photoshop to deal with those. – E-Riddie Oct 07 '14 at 14:10

score 1 · Accepted Answer · answered Oct 07 '14 at 14:18

If what you mean is that actual physical image background is white then here is possible solution using UIImageView. But bear in mind that this will work only if background is really white (as in rgb #ffffff). Also, if some other element in the image is white, it will also be colored (or in your case, disappear). Oh, and you need at least iOS7.

UIImage *yourImage = ...
UIImageView *yourImageView = ...
...
yourImageView.image = [yourImage imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
yourImageView.tintColor = [UIColor clearColor];

But it would be much better if you just modified actual image in some graphics program yourself.

score 0 · Answer 3 · answered Oct 07 '14 at 14:27

0

You may need to also set the opaque property to NO

answered Oct 07 '14 at 14:27

DeFrenZ

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Avoid white background in UIImageView

3 Answers3

Issue

Solution