Question
I have a tableview with four different types of cells. On each cell i need to place an image and labels showing with different type of text as well as label,So for better performance what i did is on scrollViewDidEndDecelerating i am trying to render the images on visible cells only. When I used reloadRowsAtIndexPaths to reload specific cell it's crashing. Showing error message as [YesNoCell compare:]: unrecognized selector sent to instance 0x1edc6a40. Any idea were i am going wrong..
Here is My code:
https://stackoverflow.com/questions/18179371
italiano
english
français
española
中国
日本の
العربية
Deutsch
한국어
Português
Russian- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
Feed *feedObject = [self.feedList objectAtIndex:indexPath.row];
BOOL isTableDecelarating = NO;
if([tableView isDecelerating]){
isTableDecelarating = YES;
}
switch ([feedObject.votingStyle intValue]) {
case 4:{
StarCell *cell =(StarCell *)[tableView dequeueReusableCellWithIdentifier:@"starCell"];
if(!cell){
NSLog(@"StarCell");
NSArray *nib = [[NSBundle mainBundle] loadNibNamed:@"StarCell" owner:self options:nil];
cell = (StarCell *)[nib objectAtIndex:0];
[cell setBackgroundColor:[UIColor clearColor]];
[cell.questionLabel setFont:[UIFont fontWithName:PROXIMA_NOVA_SEMI_BOLD size:17]];
cell.avatarButton.layer.borderWidth = 2.0f;
}
cell.feedBgImage.image = nil;
if([feedObject.feedType intValue] == 3){
if(!isTableDecelarating)
cell.feedBgImage.image = [UIImage imageNamed:[@"bg_feed" concatInt:[feedObject.feedBgType intValue]+1]];
}
else if([feedObject.feedType intValue] ==2){
cell.videoButton.hidden = NO;
UIImage *image = [[WSImageDownloader sharedInstance] cachedImageForRequest:feedObject.thumbImageURL];
if(image){
[cell.loadIndicator stopAnimating];
if(!isTableDecelarating)
cell.feedBgImage.image =image;
}
else{
[self downloadImageFor:feedObject.thumbImageURL atIndex:indexPath.row];
}
}
else{
UIImage *image = [[WSImageDownloader sharedInstance] cachedImageForRequest:feedObject.resourceId];
if(image){
[cell.loadIndicator stopAnimating];
if(!isTableDecelarating)
cell.feedBgImage.image =image;
}
else{
[self downloadImageFor:feedObject.resourceId atIndex:indexPath.row];
}
}
return cell;
break;
}
case 2:{
YesNoCell *cell =(YesNoCell *)[tableView dequeueReusableCellWithIdentifier:@"yesNoCell"];
if(!cell){
NSLog(@"YesNoCell");
NSArray *nib = [[NSBundle mainBundle] loadNibNamed:@"YesNoCell" owner:self options:nil];
cell = (YesNoCell *)[nib objectAtIndex:0];
[cell setBackgroundColor:[UIColor clearColor]];
[cell.questionLabel setFont:[UIFont fontWithName:PROXIMA_NOVA_SEMI_BOLD size:17]];
cell.avatarImage.layer.borderWidth = 2.0f;
}
cell.feedBgImage.image = nil;
if([feedObject.feedType intValue] == 3){
[cell.loadIndicator stopAnimating];
if(!isTableDecelarating)
cell.feedBgImage.image = [UIImage imageNamed:[@"bg_feed" concatInt:[feedObject.feedBgType intValue]+1]];
}
else if([feedObject.feedType intValue] ==2){
cell.videoButton.hidden = NO;
UIImage *image = [[WSImageDownloader sharedInstance] cachedImageForRequest:feedObject.thumbImageURL];
if(image){
[cell.loadIndicator stopAnimating];
if(!isTableDecelarating)
cell.feedBgImage.image =image;
}
else{
[self downloadImageFor:feedObject.thumbImageURL atIndex:indexPath.row];
}
}
else{
UIImage *image = [[WSImageDownloader sharedInstance] cachedImageForRequest:feedObject.resourceId];
if(image){
[cell.loadIndicator stopAnimating];
if(!isTableDecelarating)
cell.feedBgImage.image =image;
}
else{
[self downloadImageFor:feedObject.resourceId atIndex:indexPath.row];
}
}
return cell;
break;
}
case 3:{
YNMayBeCell *cell =(YNMayBeCell *)[tableView dequeueReusableCellWithIdentifier:@"ynmCell"];
if(!cell){
NSLog(@"YNMayBeCell");
NSArray *nib = [[NSBundle mainBundle] loadNibNamed:@"YNMayBeCell" owner:self options:nil];
cell = (YNMayBeCell *)[nib objectAtIndex:0];
[cell setBackgroundColor:[UIColor clearColor]];
[cell.questionLabel setFont:[UIFont fontWithName:PROXIMA_NOVA_SEMI_BOLD size:17]];
cell.avatarButton.layer.borderWidth = 2.0f;
}
cell.feedBgImage.image = nil;
if([feedObject.feedType intValue] == 3){
if(!isTableDecelarating)
cell.feedBgImage.image = [UIImage imageNamed:[@"bg_feed" concatInt:[feedObject.feedBgType intValue]+1]];
}
else if([feedObject.feedType intValue] ==2){
cell.videoButton.hidden = NO;
UIImage *image = [[WSImageDownloader sharedInstance] cachedImageForRequest:feedObject.thumbImageURL];
if(image){
[cell.loadIndicator stopAnimating];
if(!isTableDecelarating)
cell.feedBgImage.image =image;
}
else{
[self downloadImageFor:feedObject.thumbImageURL atIndex:indexPath.row];
}
}
else{
UIImage *image = [[WSImageDownloader sharedInstance] cachedImageForRequest:feedObject.resourceId];
if(image){
[cell.loadIndicator stopAnimating];
if(!isTableDecelarating)
cell.feedBgImage.image =image;
}
else{
[self downloadImageFor:feedObject.resourceId atIndex:indexPath.row];
}
}
return cell;
break;
}
default:{
ThumbsUpCell *cell =(ThumbsUpCell *)[tableView dequeueReusableCellWithIdentifier:@"thumbsUpCell"];
if(!cell){
NSLog(@"ThumbsUpCell");
NSArray *nib = [[NSBundle mainBundle] loadNibNamed:@"ThumbsUpCell" owner:self options:nil];
cell = (ThumbsUpCell *)[nib objectAtIndex:0];
[cell setBackgroundColor:[UIColor clearColor]];
[cell.questionLabel setFont:[UIFont fontWithName:PROXIMA_NOVA_SEMI_BOLD size:17]];
cell.avatarButton.layer.borderWidth = 2.0f;
}
cell.feedBgImage.image = nil;
[cell.loadIndicator startAnimating];
[cell.loadIndicator setHidesWhenStopped:YES];
if([feedObject.feedType intValue] == 3){
[cell.loadIndicator stopAnimating];
if(!isTableDecelarating)
cell.feedBgImage.image = [UIImage imageNamed:[@"bg_feed" concatInt:[feedObject.feedBgType intValue]+1]];
}
else if([feedObject.feedType intValue] ==2){
cell.videoButton.hidden = NO;
UIImage *image = [[WSImageDownloader sharedInstance] cachedImageForRequest:feedObject.thumbImageURL];
if(image){
[cell.loadIndicator stopAnimating];
if(!isTableDecelarating)
cell.feedBgImage.image =image;
}
else{
[self downloadImageFor:feedObject.thumbImageURL atIndex:indexPath.row];
}
}
else{
UIImage *image = [[WSImageDownloader sharedInstance] cachedImageForRequest:feedObject.resourceId];
if(image){
[cell.loadIndicator stopAnimating];
if(!isTableDecelarating)
cell.feedBgImage.image =image;
}
else{
[self downloadImageFor:feedObject.resourceId atIndex:indexPath.row];
}
}
return cell;
break;
}
}
}
Scrollview:
- (void)scrollViewDidEndDecelerating:(UIScrollView *)aScrollView
{
NSArray *visibleRows = [self.homeTableView visibleCells];
[self.homeTableView beginUpdates];
[self.homeTableView reloadRowsAtIndexPaths:visibleRows withRowAnimation:UITableViewRowAnimationNone];
[self.homeTableView endUpdates];
}
Solution
That's because reloadRowsAtIndexPaths: expects an array of indexPaths, but you are providing a list of table view cell objects.
Just change the line
NSArray *visibleRows = [self.homeTableView visibleCells];
into
NSArray *visibleRows = [self.homeTableView indexPathsForVisibleRows];
OTHER TIPS
I was stuck in this problem for 1 and half day.
Here is my code.
-(void)ShowtableHeight:(NSIndexPath*)indexpath
{
NSArray *visibleRows = [recTableView indexPathsForVisibleRows];
[recTableView reloadRowsAtIndexPaths:visibleRows withRowAnimation:UITableViewRowAnimationNone];
}
I called this function from
- (void)webViewDidFinishLoad:(UIWebView *)aWebView
My tableView Rows Were displaying data in webView.
So for dynamic height of data I wrote ShowtableHeight function. And the indexpath parameter for ShowtableHeight function come from webViewDidFinishLoad function like this,
NSIndexPath *index = [recTableView indexPathForCell:cell];
And if you want to pass section as parameter then you can write following in webViewDidFinishLoad accordingly
NSString *key = [dateArr objectAtIndex:index.section];
This will pass the number of sections in tableview.
