I can't understand why I can't set the uimageview from url from the example below:
NSData *data = [NSData dataWithContentsOfURL:[NSURL URLWithString:#"http://a4.mzstatic.com/us/r30/Music/08/e9/14/mzi.lmcnwrii.60x60-50.jpg"]];
UIImage *image = [UIImage imageWithData:data];
self.imgAlbum1 = [[UIImageView alloc] initWithImage:image];
it works fine by browsing the image, IBOutlet is ok, even setting uiimage from imagenamed doesn't work
I tried to recreate the contorl in the storyboard but nothing...
any tips are appreciated
Presumably imgAlbum1 is an outlet to your existing image view.
Instead of that last line, which tries to create a new image view without displaying it anywhere, you probably want:
self.imgAlbum1.image = image;
Edit: If your imgAlbum1 is an IBOutlet, you probably set it as a WEAK property. If that is the case, the image will never show up. In order to use alloc, your property would have to be a STRONG property.
Since you are probably using a WEAK outlet, try using self.imgAlbum1 as the other poster suggested. The reason this will work though, is because you're just updating the image, not the actual imageView object (weak properties, when you re-alloc will essentially destroy the object completely).
This is what I did which I tested and works just fine:
NSString *encodedString = [[NSString stringWithFormat:#"%#", #"us/r30/Music/08/e9/14/mzi.lmcnwrii.60x60-50.jpg"] stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
NSURL *imageURL = [NSURL URLWithString:[NSString stringWithFormat:#"http://a4.mzstatic.com/%#", encodedString]];
NSData *data = [NSData dataWithContentsOfURL:imageURL];
UIImage *image = [[UIImage alloc] initWithData:data];
UIImageView *imgAlbum1 = [[UIImageView alloc] initWithImage:image];
[self.view addSubview:imgAlbum1];
So the questions for me are:
Are you using a WEAK property for imgAlbum1 (ie: #property (nonatomic, weak) IBOutlet *imgAlbum1)? If so, don't set it to strong - rather, just use self.imgAlbum1.image = image;
Have you ensured you have an internet connection with the device you are using?
Is imgAlbum1 an IBOutlet to a UIImageView ? If so, is it hidden (or hidden by a layer)?
Are you on the right view controller?
etc.
Otherwise, the code seems fine.
Related
I've searched through all similar questions but I couldn't find the answer. I'm completely stumped on this... I have a class that extends UIImageView. So here's my .h file:
#interface Paper : UIImageView {
#public
CGFloat drag;
}
#property (nonatomic, assign) CGFloat drag;
#end
I'm synthesizing drag properly in my implementation.
Now, in my ViewController, I create and initialize a Paper object like so:
NSString *tempPath = [[NSBundle mainBundle] pathForResource:#"picture" ofType:#"png"];
UIImage *tempImage = [[UIImage alloc] initWithContentsOfFile:tempPath];
Paper *tempPaper = [[UIImageView alloc] initWithImage: tempImage];
The object is created right, I can later display it as a subview and all that jazz, but when I try to change my custom property immediately after the above using a line like:
tempPaper.drag = 1.0;
or
[tempPaper setDrag:1.0];
I get [UIImageView setDrag:]: unrecognized selector sent to instance as an error. I have tried every different method I've found but it won't allow me to set the value of my custom properties (the non-UIImageView ones) for the Paper class. What is it I'm missing? I've spent 2 hours on this and it's driving me nuts, I don't see what's wrong.
I've also tried initializing drag in Paper's initWithImage method, but it doesn't work either.
Paper *tempPaper = [[Paper alloc] initWithImage: tempImage];
Create object of Paper class instaed of UIImageView.
Paper *tempPaper = [[Paper alloc] initWithImage: tempImage];
i have this scroll view, that I'm loading into him few images from URL.
the problem is that the scroll view don't show any of them until that all loaded.
i want to show every image the moment i finished loading her.
my code looks like this:
-(void)loadPhotosToLeftscroll{
for (int count = 0 ; count < [leftPhotoArray count]; count++) {
NSLog(#"nextPhotoHight: %f",nextLeftPhotoHight);
NSMutableDictionary *photoDict;
photoDict = [leftPhotoArray objectAtIndex:count];
float photoHight = [[photoDict objectForKey:#"photos_height"]floatValue];
float photoWide= [[photoDict objectForKey:#"photos_width"]floatValue];
NSString *photoPath = [photoDict objectForKey:#"photos_path"];
NSData * imageData = [[NSData alloc] initWithContentsOfURL: [NSURL URLWithString:photoPath]];
UIImage *image = [[UIImage alloc] initWithData:imageData];
UIImageView *photoView = [[UIImageView alloc]initWithFrame:CGRectMake(10 , nextLeftPhotoHight, photoWide, photoHight )];
[photoView setImage:image];
[photoView.layer setMasksToBounds:YES];
[photoView.layer setCornerRadius:6];
nextLeftPhotoHight = photoView.frame.size.height + photoView.frame.origin.y + 10;
[leftBlockScroll addSubview:photoView];
}
}
You better use a asynchronous way to do that.
Relative topic is NSURLConnection, UIImageView.
I have done something similar before.
1. Create a new model inherit to UIView
2. This model will have a UIImageView, NSData
3. When u init the model, pass in a URL
4. Use NSURLConnection to send out AsynchroizedRequest
5. By using NSURLConnection delegate, you will finally get the Data of the image
6. Init a UIImage with these data
7. Init The UIImageView with this Image
8. Add this imageview to this model or directly pointing this model to the imageview
Feel free to ask for more detail :)
I m loading lots of rather large images in my viewcontroller, using
NSUInteger nimages = 0;
for (; ; nimages++) {
NSString *nameOfImage_ = #"someName";
NSString *imageName = [NSString stringWithFormat:#"%#%d.jpg", nameOfImage_, (nimages + 1)];
image = [UIImage imageNamed:imageName];
if (image == nil) {
break;
}
UIImageView *imageView = [[UIImageView alloc] initWithImage:image];
//some other stuff....
[imageView release];
}
the usual unloading occurs in - (void)viewDidUnload and - (void)dealloc
with self.image = nil; and [image release];
It seems after a few "loading" and "unloading" the cache still grows to the point of no return!!
:)
and the app crashes...
any ideas??? how do i empty my cache? and where?
thanks
EDIT:
ok this is what i was doing wrong.
Apparently this piece of code fixes the whole caching problem:
image = [[UIImage imageNamed:imageName] autorelease];
with autorelease being the key here.
thanks for the replies...
Thank you all for your suggestions.
Solution:
Used ARC and imageWithContentsOffFile to initialize the Images.
image = [UIImage imageWithContentsOfFile: [[NSBundle mainBundle] pathForResource:imageName ofType:nil]];
And Yes, imageNamed is only good for... well for nothing big...
image = [[UIImage imageNamed:imageName] autorelease];
This is incorrect. In keeping with the memory management rules, you shouldn't be releasing (or autoreleasing) the image because you didn't allocate or retain it. "imageNamed" doesn't contain "alloc", "new", "copy", or "retain".
As some of the other answers explain, you should load your images with a different method if you want more control over the memory they use.
imageNamed is an awful way to load images in reality, it never releases loaded images unless forced and keeps them in the cache forever. You should implement your own, more intelligent cache. A simple NSMutableDictionary gives the same functionality but with more flexibility.
For a more in-depth discussion you can read this: http://www.alexcurylo.com/blog/2009/01/13/imagenamed-is-evil/
Use another method to initialize you image. imageNamed caches.
Instead of using using imageNamed you can use imageWithContentsOfFile:
Or check this article
link 0
link 1
I'm trying to use a url as a UIImage in the OpenFlow API.
NSString *imageUrl = [[[newsEntries objectAtIndex:0] objectForKey: #"still"] retain];
NSURL *url2 = [NSURL URLWithString:imageUrl];
NSData *photoData = [NSData dataWithContentsOfURL:url2];
UIImage *imageUI = [UIImage imageWithData:photoData]
UIImageView *myImage = [UIImageView initWithFrame:imageUI];
[(AFOpenFlowView *)self.view setImage:[UIImage imageNamed:myImage]];
[imageUr release];
[(AFOpenFlowView *)self.view setNumberOfImages:3];
I have tried it like this, but no success. The only way I got this API working was using the imageNamed type. The initwithData has no success.
So how can I change this NSString to finally become a imageNamed method?
A UIImageView is different from a UIImage.
Change this line: [(AFOpenFlowView *)self.view setImage:[UIImage imageNamed:myImage]];
To this: [(AFOpenFlowView *)self.view setImage:[UIImage imageNamed:imageUI]];
and it should work.
You have several significant errors here. It appears that you may need to read about C/Objective-C and types.
It sounds like you are asserting that, specifically, the line
UIImage *imageUI = [UIImage imageWithData:photoData]
is not working. The code up to that point actually looks okay (though it is not necessary to retain and then release the imageUrl variable.
Once you have created your UIImage, you should be able to pass it directly to your AFOpenFlowView:
[(AFOpenFlowView*)self.view setImage:imageUI forIndex:0];
The line
UIImageView *myImage = [UIImageView initWithFrame:imageUI];
has two errors (and is unnecessary anyway). First, -initWithFrame takes a CGRect as its argument, not a UIImage. UIImageView does have an initialization method -initWithImage, which is probably what you intended. But either way, methods that start with "init" are instance methods, not class methods, so you have to call them on actual instances of a UIImageView, like this:
UIImageView *myImage = [[UIImageView alloc] initWithImage:imageUI];
Note that this will leak memory unless you autorelease or release it.
The following line, you correctly try to give a UIImage to your AFOpenFlowView, but you attempt to create that UIImage by passing a UIImageView to the +imageNamed method. +imageNamed takes an NSString that contains the name of the image, and passing anything else to it won't work.
You must always be aware of what kind of object a method is expecting to receive, and make sure you find some way to give it that kind of thing.
Probably what you are looking for here is something like this:
NSString *imageUrl = [[newsEntries objectAtIndex:0] objectForKey: #"still"];
NSString *imageName = [imageUrl lastPathComponent];
[(AFOpenFlowView *)self.view setImage:[UIImage imageNamed:imageName]];
i asked this question yesterday but it doesnt seem to have asked properly so im trying again
in my app im parsing in an xml file , in that file there is a path for an image to download
an in my tableview controler i have this to download the image and display it in the cell
NSURL *url = [NSURL URLWithString:aStory.picture];
NSData *data = [NSData dataWithContentsOfURL:url];
UIImage *img = [[UIImage alloc] initWithData:data];
im then pushing another view controller on the top and displaying some text in a text view , but i also want to take the image from the cell selected and put that in there too , but everything i try does not work.
any ideas on how i can do this
Thanks in advance
Richard
You need to create a property in the target ViewController to hold the image
UIImage *myDownloadedImage;
}
#property (nonatomic, assign) UIImage *myDownloadedImage;
and then when you are about to push you add the image to the controller
myNextViewController.myDownloadedImage = img;
[self.navigationController pushViewController:myNextViewController animated:YES];
Now you have access to the image to do as you wish