Why doesn't the cell show anything in this code:
UIActivityIndicatorView *spinner = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
[cell.imageView addSubview:spinner];
[spinner startAnimating];
cell.textLabel.text=#"Carregando...";
[spinner release];
I'm doing this inside tableView:cellForRowAtIndexPath:.
I tried size to fit, create a frame to cell.imageView and a same size frame to the spinner, but nothing works.
What´s wrong with this code?
Thank you..!
A slight modification of the method from Thiago:
I think adding the spinner directly to the cell view felt a little hacky, so I used a 1x1 transparent png as the image view and resized it to be whatever my spinner size is:
UITableViewCell *cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:#"NoReuse"] autorelease];
cell.textLabel.text = #"Loading...";
UIActivityIndicatorView *spinner = [[[UIActivityIndicatorView alloc]
initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray] autorelease];
// Spacer is a 1x1 transparent png
UIImage *spacer = [UIImage imageNamed:#"spacer"];
UIGraphicsBeginImageContext(spinner.frame.size);
[spacer drawInRect:CGRectMake(0,0,spinner.frame.size.width,spinner.frame.size.height)];
UIImage* resizedSpacer = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
cell.imageView.image = resizedSpacer;
[cell.imageView addSubview:spinner];
[spinner startAnimating];
return cell;
That gives a cell that looks like this:
I found the answer...
David Maymudes was partialy right... It´s necessary to have a "background" to the cell.imageView... But must be a image, not just a frame. So just create a UIImage as a "white background" and set in cell.imageView.image. The code will be:
UIActivityIndicatorView *spinner = [[UIActivityIndicatorView alloc]
initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
UIImage *whiteback = [[UIImage alloc] initWithContentsOfFile:#"whiteback.png"];
cell.imageView.image = whiteback;
[cell.imageView addSubview:spinner];
[spinner startAnimating];
cell.textLabel.text=#"Carregando...";
[whiteback release];
[spinner release];
The whiteback.png is just a 25x25 pixels white square...
Thanks for everyone help... See you...
I think the cell's imageView will probably have a zero-size rectangle, because you haven't put a picture in it. So the spinner is inside but invisible.
So instead of putting the spinner within the imageView, just put it within the cell...
[cell addSubview:spinner];
spinner.frame = CGRectMake(145, 0, 30, 30); // if you want it centered horizontally...
you could also do
cell.accessoryView = spinner;
to put the spinner over at the far right of the cell.
Related
I am using AsyncImageView classes to apply lazy loading on UITableView. And want to apply activity indicator on image view until the image is loaded on cell. Below is my code i am trying.
// AsyncIamgeView.m
- (void)connectionDidFinishLoading:(NSURLConnection*)theConnection {
//[connection release];
UIActivityIndicatorView *indicator = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleWhite];
indicator.center = CGPointMake(15, 15);
connection=nil;
if ([[self subviews] count]>0) {
[[[self subviews] objectAtIndex:0] removeFromSuperview];
}
UIImage *imgData = [UIImage imageWithData:data];
UIImageView* imageView = [[UIImageView alloc]init];
[imageView addSubview:indicator];
[indicator startAnimating];
if(imgData == nil)
{
imageView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"NoImagenew.png"]];
//[indicator stopAnimating];
}
else{
imageView = [[UIImageView alloc] initWithImage:imgData];
// [indicator stopAnimating];
}
//imageView.contentMode = UIViewContentModeScaleAspectFit;
//imageView.autoresizingMask = ( UIViewAutoresizingFlexibleWidth || UIViewAutoresizingFlexibleHeight );
//[imageView sizeToFit];
[self addSubview:imageView];
imageView.frame = self.bounds;
//imageView.frame = CGRectMake(0, 0, 85, 94);
[imageView setNeedsLayout];
[self setNeedsLayout];
//[data release];
data=nil;
}
// cellForRowAtIndexPath method.
asyncImageView = [[AsyncImageView alloc]initWithFrame:CGRectMake(1, 3, 85, 54)];
[asyncImageView loadImageFromURL:[NSURL URLWithString:imageUrlString]];
[cell.contentView addSubview:asyncImageView];
This code shows activity indicator but when image is loaded after that not before loading images. Please guide for above.
You have to create AsyncImageView object instead of UIImageView, then it will automatically add indicator to your view
AsyncImageView *imageView = [[AsyncImageView alloc] initWithFrame:CGRectMake(1, 3, 85, 54)];
[cell addSubview:imageView];
//cancel loading previous image for cell
[[AsyncImageLoader sharedLoader] cancelLoadingImagesForTarget:imageView];
//load the image
imageView.imageURL = [imageURLs objectAtIndex:indexPath.row];
Here is an example of this
Currently you are adding activity indicator when your image is downloaded.
Here is the simple idea, hope you can implement this in your code
- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse *)response
{
// This method is called when your connection receives a response
// add your activity indication here and start animating
}
- (void)connectionDidFinishLoading:(NSURLConnection *)connection
{
// This method is called when your image is downloaded.
// remove your activity indicator or stop animating here
}
Hope u downloaded AsyncImageView from https://github.com/nicklockwood/AsyncImageView. By default, it has the feature to show activity indicator. You just dont need to add or remove any code by yourself to get this feature works. Just call loadImageWithURL.
I think u are using asynimageview classs, In that by default you will get the loader in the cell itself .
AysncImageView already has a loader.
You won't see it if your background is black since it loads the default activity indicator.
So, just set the activityIndicatorStyle property for your AsyncImageView object based on your background.
In my case, my background was black, so I used the following code :
asyncImgView.activityIndicatorStyle = UIActivityIndicatorViewStyleWhite;
i want to animate tableviewcell background image with two blinking images on didSelectRowAtIndexPath. We can use following code, but it will show one image in background. However I want gif like image which blinks.
cell.backgroundView = [ [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"correctAnswer.png"]]autorelease];
UIImageView has the ability to do animation with the animationImages property.
UIImageView* imgView = [[[UIImageView alloc] init] autorelease];
imgView.animationImages = [NSArray arrayWithObjects:
[UIImage imageNamed:#"correctAnswer1.png"],
[UIImage imageNamed:#"correctAnswer2.png"], nil];
imgView.animationDuration = 0.5;
cell.backgroundView = imgView;
[imgView startAnimating];
You need to have each frame of the animation included in your project, correctAnswer1.png, correctAnswer2.png, etc...
Also, wouldn't it be better to use UITableViewCell's imageView property? That way you would get your animation in the left of the cell and it wouldn't interfere with the text or any other parts of the cell...
I have the following code which draws a separator line and text for a UITableViewCell. It looks fine but when I scroll off screen then back, the separator line is gone but the text is still fine. Any ideas?
static NSString *aProgressIdentifier = #"CustomerCell";
UITableViewCell *aCustomerCell = [iTableView dequeueReusableCellWithIdentifier:aProgressIdentifier];
if (!aCustomerCell) {
aCustomerCell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:aProgressIdentifier] autorelease];
aCustomerCell.contentView.backgroundColor = [UIColor whiteColor];
UIImageView *aLine = [[UIImageView alloc] initWithFrame:CGRectMake(0, 72, 800, 1)];
aLine.backgroundColor = [UIColor colorWithWhite:0.9 alpha:1.0];
[aCustomerCell addSubview:aLine];
[aLine release];
}
CMACustomer *aCustomerObject = aCellObject;
aCustomerCell.textLabel.text = aCustomerObject.customerFullName;
aCustomerCell.detailTextLabel.text = nil;
aCell = aCustomerCell;
Try to add the "aLine" image view as subview of the contentView and not the whole table itself. Probably when the cell is reused and then layoutSubviews is called again, the contentView overlaps (white background) your aLine. Infact consider that iOS default cells have their subviews dynamically redrawn and resized each time they are displayed on screen.
So I would try this:
[aCustomerCell.contentView addSubview:aLine];
If this doesn't work, what can you do is to remove the contentView completely and add your own custom subviews (do this inside the if(!aCustomerCell) and not outside unless you will not get the benefits of the cell re-use):
if (!aCustomerCell) {
aCustomerCell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:aProgressIdentifier] autorelease];
[cell.subviews makeObjectsPerformSelector:#selector(removeFromSuperview)];
UIImageView *aLine = [[UIImageView alloc] initWithFrame:CGRectMake(0, 72, 800, 1)];
aLine.backgroundColor = [UIColor colorWithWhite:0.9 alpha:1.0];
[aCustomerCell.contentView addSubview:aLine];
[aLine release];
}
Finally another check is verify that the cell height is > 72 (it seems a trivial check but its often source of headaches!).
The table view is using a pool of cells, so you can't be sure which one you're getting for any given index path. You can use the cell or the content view, but be sure to add only one of your custom lines per cell.
UIImageView *aLine = (UIImageView *)[cell viewWithTag:64];
if (!aLine) {
// etc.
UIImageView *aLine = [[UIImageView alloc] initWithFrame:CGRectMake(0, 72, 800, 1)];
aLine.tag = 64;
[cell addSubview:aLine];
//
}
// other formatting logic here, you can also hide/show aLine based on biz logic
try adding it to the contentView
[aCustomerCell.contentView addSubview:aLine]
I have a TTTableViewController with a background image in which I insert items of type TTTableLink. Running the app if I drag the cells out of the screen by scrolling up and down for example, when they enter the screen again their background colour is changed to white. I have noticed this problem only in iOS5.
I don't really get when the background is changed, any ideas of how to preserve clear background for the table cells
Here is my code:
-(void) loadView {
[super loadView];
UIImage *backgroundImage = [UIImage imageWithContentsOfFile:[[NSBundle mainBundle] pathForResource:#"imageName" ofType:#"png"]];
UIImageView *backgroundView = [[UIImageView alloc] initWithImage:backgroundImage];
backgroundView.frame = CGRectMake(0, 0, 320, 416);
[self.view addSubview:backgroundView];
[self.view sendSubviewToBack:backgroundView];
[backgroundView release];
self.tableView.backgroundColor = [UIColor clearColor];
}
-(void) createModel {
TTListDataSource* listDataSource= [[[TTListDataSource alloc] init] autorelease];
TTTableLink *item = [TTTableLink itemWithText:itemName URL:targetURL];
[listDataSource.items addObject:item];
}
There's a pending pull request on three20 which fixes this issue. see https://github.com/facebook/three20/pull/689. post a comment on it, so the repo owner will merge it. I think he forgot about this project :-)
or you can either fix it by changing that line in your source code
I'm new to programming, and I know how to add a static image behind a tableView in a .xib file, but not in code. I have tried the following code:
UIImage * image = [UIImage imageNamed:#"pic.png"];
[self.view addSubView: image];
but nothing happens when I write this!
To display an UIImage you have to use an UIImageView and put it under the UITableView using the same frame. Don't forget to set the table view's background to transparent.
UIImageView *iv = [[UIImageView alloc] initWithImage:[UIImage imageNamed:#"pic.png"]];
iv.frame = CGRectMake(0.0, 0.0, 300.0, 600.0);
UITableView *tv = [[UITableView alloc] initWithFrame:iv.frame style:UITableViewStylePlain];
tv.opaque = NO;
tv.backgroundColor = [UIColor clearColor];
[self.view addSubView: iv];
[self.view addSubView: tv];
[iv release];
[tv release];
You need to use a UIImageView, not a UIImage. Also, when adding a view programmatically, don't forget to set the frame.