I am wanting to add a custom background and selected background images for my tableview cells. Currently it seems that when the cells get reused, the background images get screwed up, the top cell will use the bottom cells image, etc etc.
Am I reusing cells incorrectly in this case?
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
UIImageView *linkAvailableImageView = nil;
UIView *backgroundView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, tableView.bounds.size.width, 44)];
UIView *selectedBackgroundView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, tableView.bounds.size.width, 44)];
UIImageView *backgroundImage = [[UIImageView alloc] initWithFrame:CGRectMake(10, 0, tableView.bounds.size.width-20, 44)];
UIImageView *selectedBackgroundImage = [[UIImageView alloc] initWithFrame:CGRectMake(10, 0, tableView.bounds.size.width-20, 44)];
// Asset
Asset *asset = nil;
asset = (Asset *)[items objectAtIndex:indexPath.row];
int count = [items count];
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
if (indexPath.row == 0 && count > 1) {
backgroundImage.frame = CGRectMake(10, 0, tableView.bounds.size.width-20, 45);
backgroundImage.image = [[UIImage imageNamed:#"MDACCellBackgroundTop.png"] stretchableImageWithLeftCapWidth:5 topCapHeight:10];
selectedBackgroundImage.frame = CGRectMake(10, -1, tableView.bounds.size.width-20, 45);
selectedBackgroundImage.image = [[UIImage imageNamed:#"MDACCellBackgroundSelectedTop.png"] stretchableImageWithLeftCapWidth:5 topCapHeight:10];
} else if (indexPath.row == count-1 && count > 1) {
backgroundImage.image = [[UIImage imageNamed:#"MDACCellBackgroundBottom.png"] stretchableImageWithLeftCapWidth:5 topCapHeight:10];
selectedBackgroundImage.image = [[UIImage imageNamed:#"MDACCellBackgroundSelectedBottom.png"] stretchableImageWithLeftCapWidth:5 topCapHeight:10];
} else if (indexPath.row == 0 && count == 1) {
backgroundImage.frame = CGRectMake(10, -1, tableView.bounds.size.width-20, 45);
backgroundImage.image = [[UIImage imageNamed:#"MDACCellBackgroundSingle.png"] stretchableImageWithLeftCapWidth:5 topCapHeight:10];
selectedBackgroundImage.image = [[UIImage imageNamed:#"MDACCellBackgroundSelectedSingle.png"] stretchableImageWithLeftCapWidth:5 topCapHeight:10];
} else {
backgroundImage.image = [[UIImage imageNamed:#"MDACCellBackgroundMiddle.png"] stretchableImageWithLeftCapWidth:1 topCapHeight:10];
selectedBackgroundImage.image = [[UIImage imageNamed:#"MDACCellBackgroundSelectedMiddle.png"] stretchableImageWithLeftCapWidth:1 topCapHeight:10];
}//end
backgroundImage.autoresizingMask = UIViewAutoresizingFlexibleWidth;
[backgroundView addSubview:backgroundImage];
[backgroundImage release];
selectedBackgroundImage.autoresizingMask = UIViewAutoresizingFlexibleWidth;
[selectedBackgroundView addSubview:selectedBackgroundImage];
[selectedBackgroundImage release];
cell.backgroundView = backgroundView;
[backgroundView release];
cell.selectedBackgroundView = selectedBackgroundView;
[selectedBackgroundView release];
linkAvailableImageView = [[[UIImageView alloc] initWithFrame:CGRectMake(cell.contentView.bounds.size.width-39, 9, 24, 24)] autorelease];
linkAvailableImageView.autoresizingMask = UIViewAutoresizingFlexibleLeftMargin;
linkAvailableImageView.image = [UIImage imageNamed:#"MDACLinkArrow.png"];
linkAvailableImageView.tag = 3;
[cell.contentView addSubview:linkAvailableImageView];
} else {
linkAvailableImageView = (UIImageView *)[cell.contentView viewWithTag:3];
}
// Get asset
cell.textLabel.opaque = NO;
cell.textLabel.text = asset.name;
cell.textLabel.font = [UIFont boldSystemFontOfSize:17];
cell.textLabel.backgroundColor = [UIColor colorWithWhite:94./255. alpha:1];
cell.textLabel.textColor = [UIColor whiteColor];
cell.textLabel.shadowColor = [UIColor colorWithWhite:0 alpha:0.6];
cell.textLabel.shadowOffset = CGSizeMake(0, -1);
// Set the kind of disclosure indicator
if ([asset.children intValue] > 0) {
//cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
} else {
cell.accessoryType = UITableViewCellAccessoryNone;
}//end
// Lazy Load the image
if (!asset.appIcon) {
// Download icon
[self startIconDownload:asset forIndexPath:indexPath];
// if a download is deferred or in progress, return a placeholder image
cell.imageView.image = [UIImage imageNamed:#"default-icon.png"];
} else {
cell.imageView.image = asset.appIcon;
}//end
return cell;
}//end
The problem here is that you are using the same cell identifier regardless of the position in the table view.
So you initially create the cells based on the indexPath.row and the count, but you associate those cells with an identifier of #"Cell". So when you scroll down dequeueReusableCellWithIdentifier will return a cell configured for the beginning of the list (indexPath.row == 0 && count > 1) and use it for the end of the list.
You need to make sure cell identifier reflects the code at the beginning of your cell==nill if block, so that you only reuse cells that have been configured for the position in the table you are creating.
As Eiko points out, you are also leaking your UIView and UIImageView objects. You could stick them in the if block, release them explicitly or just make them autorelease.
Sorry, but that code has lots of problems: You are leaking the UIView and UIImageView objects, and the whole reuse of cells is wrong, hence your problems.
You should set up a new cell (with views) only in the if (cell == nil) part, and don't forget to release/autorelease your views. Then, outside of that block, you configure your cell accordingly (set its contents).
I strongly suggest to look through some of Apple's example projects!
Related
I am experiencing performance problems when using some subviews on my UITableViewCells. After I keep scrolling it eventually starts getting very slow.
First step I am doing is creating a common UIView for every cell, essentially this is creating a white cell with a rounded effect on the cell with a shadow. The performance for this seems to be normal so I don't think it's the culprit.
Here is the code I am using to do this:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *NewsCellIdentifer = #"NewsCellIdentifier";
NewsItem *item = [self.newsArray objectAtIndex:indexPath.row];
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:NewsCellIdentifer];
if (cell == nil)
{
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:NewsCellIdentifer];
cell.contentView.backgroundColor = [UIColor clearColor];
UIView *whiteRoundedCornerView = [[UIView alloc] initWithFrame:CGRectMake(10,10,300,100)];
whiteRoundedCornerView.backgroundColor = [UIColor whiteColor];
whiteRoundedCornerView.layer.masksToBounds = NO;
whiteRoundedCornerView.layer.cornerRadius = 3.0;
whiteRoundedCornerView.layer.shadowOffset = CGSizeMake(-1, 1);
whiteRoundedCornerView.layer.shadowOpacity = 0.5;
[cell.contentView addSubview:whiteRoundedCornerView];
[cell.contentView sendSubviewToBack:whiteRoundedCornerView];
cell.layer.shouldRasterize = YES;
cell.layer.rasterizationScale = [UIScreen mainScreen].scale;
cell.layer.opaque = YES;
cell.opaque = YES;
}
[cell.contentView addSubview:[self NewsItemThumbnailView:item]];
return cell;
}
Here is the method that returns the thumbnail view of the graphic and text:
- (UIView *) NewsItemThumbnailView:(NewsItem *)item
{
UIView *thumbNailMainView = [[UIView alloc] initWithFrame:CGRectMake(10, 10, 50, 70)];
UIImageView *thumbNail = [[UIImageView alloc] initWithImage:[UIImage imageNamed:item.ThumbNailFileName]];
thumbNail.frame = CGRectMake(10,10, 45, 45);
UILabel *date = [[UILabel alloc] init];
date.frame = CGRectMake(10, 53, 45, 12);
date.text = item.ShortDateString;
date.textAlignment = NSTextAlignmentCenter;
date.textColor = [BVColors WebDarkGrey];
CGFloat fontSize = 10.0;
date.font = [BVFont Museo:&fontSize];
date.opaque = YES;
thumbNail.opaque = YES;
thumbNailMainView.opaque = YES;
[thumbNailMainView addSubview:thumbNail];
[thumbNailMainView addSubview:date];
return thumbNailMainView;
}
The performance problem seems to be when I add the thumbnail view to the cell because when I comment that line out, I don't seem to have it. The thumbnail information is dynamic and will change with each cell. I would appreciate any advice on how I should do this without degrading the performance.
UITableView will call tableView:cellForRowAtIndexPath: each time a cell comes into view, and dequeueReusableCellWithIdentifier: will reuse existing cell objects if they are available. These two facts combine to put you in a scenario where every time you scroll, the same finite number of cell objects end up with an increasing number of subviews.
The proper approach is to create a custom UITableViewCell subclass that has a property for thumbnailView. In the setter for that property, remove the previous thumbnail (if any) and then add the new one to the contentView. This ensures that you'll only ever have one thumbnail subview at any time.
A less optimal approach would be adding a tag to the UIView returned from NewsItemThumbnailView (thumbNailMainView.tag = someIntegerConstant) and then searching for any view with that tag and removing it before adding another:
// remove old view
UIView *oldThumbnailView = [cell.contentView viewWithTag:someIntegerConstant];
[oldThumbnailView removeFromSuperview];
// add new view
[cell.contentView addSubview:[self NewsItemThumbnailView:item]];
I ended up leveraging a solution found on this stackoverflow post:
How should I addSubview to cell.contentView?
Essentially when the cell is first initialized I am setting the view as mentioned by Nishant; however once the cell is reused I am extracting out the items I need to change, such as an UIImageView and then a UILabel. Since these are pointers I can modify just what I need when I need to and the performance is fast again. Here is a abbreviated version of what I did.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *NewsCellIdentifer = #"NewsCellIdentifier";
NewsItem *item = [self.newsArray objectAtIndex:indexPath.row];
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:NewsCellIdentifer];
UIView *thumbNailMainView = [[UIView alloc] initWithFrame:CGRectMake(10, 10, 50, 70)];
UIImageView *thumbNail;
UIView *textMainView = [[UIView alloc] initWithFrame:CGRectMake(20,20,80,80)];
UILabel *headerLabel = [[UILabel alloc] initWithFrame:CGRectMake(52,-5, 70, 20)];
UILabel *teaserLabel = [[UILabel alloc] initWithFrame:CGRectMake(50,20, 210, 40)];
UIView *newsItemCornerMainView = [[UIView alloc] initWithFrame:CGRectMake(255.7, 55.2, 55, 55)];
UIImageView *cornerIconView;
// If the cell doesn't existing go ahead and make it fresh.
if (cell == nil)
{
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:NewsCellIdentifer];
// Configure all the various subviews
..... //Sample below
// Make the title view
headerLabel.text = item.Title;
CGFloat textfontSize = 16.0f;
headerLabel.font = [BVFont Museo:&textfontSize];
headerLabel.textColor = [BVColors WebBlue];
headerLabel.textAlignment = NSTextAlignmentLeft;
headerLabel.numberOfLines = 0;
headerLabel.tag = 50;
// Make the Teaser view
teaserLabel.text = item.Teaser;
teaserLabel.numberOfLines = 0;
CGFloat tfontSize = 13.0f;
teaserLabel.textAlignment = NSTextAlignmentLeft;
teaserLabel.textColor = [BVColors WebDarkGrey];
teaserLabel.font = [BVFont HelveticaNeue:&tfontSize];
[teaserLabel sizeToFit];
teaserLabel.tag = 51;
[textMainView addSubview:headerLabel];
[textMainView sendSubviewToBack:headerLabel];
[textMainView addSubview:teaserLabel];
[cell.contentView addSubview:textMainView];
....
}
thumbNail = (UIImageView *) [cell viewWithTag:47];
[thumbNail setImage:[UIImage imageNamed:item.ThumbNailFileName]];
headerLabel = (UILabel *) [cell viewWithTag:50];
headerLabel.text = item.Title;
teaserLabel = (UILabel *) [cell viewWithTag:51];
teaserLabel.text = item.Teaser;
cornerIconView = (UIImageView *) [cell viewWithTag:48];
[cornerIconView setImage:[UIImage imageNamed:item.CornerIconFileName]];
return cell;
}
You should change thumbNailMainView content only everytime but you should not add its content on cell everytime.
So add this line where you are allocating cell
[cell.contentView addSubview:[self NewsItemThumbnailView:item]];
add this inside braces. and then access thumbNailMainView from cell and pass that item data which you need to change for each cell.
Assign a tag to thumbNailMainView and its subview thumbNail then access it as
UIView *_thumbNailMainView = [cell.contentView viewWithTag:_thumbNailMainView_tag];
UIImageView *_thumbNail = [_thumbNailMainView viewWithTag:thumbNail_tag];
_thumbNail.image = [UIImage imageNamed:item.ThumbNailFileName];
Hope it helps you.
I have added UIImageView in GMGridView as I want to display the images in grid. After adding imageview in grid all works perfectly. I want to show different image in first row & first column. So I set that image after compairing with index.
But when I scroll up & down , it changes the image from first column to 2nd or 3rd column. Also same image is shown in the 6th or 7th row. What going wrong in this? Here is my code
- (GMGridViewCell *)GMGridView:(GMGridView *)gridView cellForItemAtIndex:(NSInteger)index
{
CGSize size = [self GMGridView:gridView sizeForItemsInInterfaceOrientation:[[UIApplication sharedApplication] statusBarOrientation]];
GMGridViewCell *cell = [gridView dequeueReusableCell];
UIImageView *imageView = nil;
if (!cell)
{
cell = [[GMGridViewCell alloc] init];
cell.deleteButtonIcon = [UIImage imageNamed:#"close_x.png"];
cell.deleteButtonOffset = CGPointMake(-15, -15);
imageView = [[UIImageView alloc]initWithFrame:CGRectMake(0, 0, size.width, size.height)];
cell.contentView = imageView;
}
NSLog(#"Project Index value:- %d",index);
if (index == 0) {
imageView.image = [UIImage imageNamed:#"add.png"];
}
else{
imageView.image = [UIImage imageNamed:#"face.png"];
}
[[cell.contentView subviews] makeObjectsPerformSelector:#selector(removeFromSuperview)];
return cell;
}
Also do I need [[cell.contentView subviews] makeObjectsPerformSelector:#selector(removeFromSuperview)]; ?
Can anybody help me ? Thanks
Try using the code
- (GMGridViewCell *)GMGridView:(GMGridView *)gridView cellForItemAtIndex:(NSInteger)index {
CGSize size = [self GMGridView:gridView sizeForItemsInInterfaceOrientation:[[UIApplication sharedApplication] statusBarOrientation]];
GMGridViewCell *cell = [gridView dequeueReusableCell];
UIImageView *imageView = nil;
if (!cell)
{
cell = [[GMGridViewCell alloc] init];
cell.deleteButtonIcon = [UIImage imageNamed:#"close_x.png"];
cell.deleteButtonOffset = CGPointMake(-15, -15);
imageView = [[UIImageView alloc]initWithFrame:CGRectMake(0, 0, size.width, size.height)];
NSLog(#"Project Index value:- %d",index);
if (index == 0) {
imageView.image = [UIImage imageNamed:#"add.png"];
}
else{
imageView.image = [UIImage imageNamed:#"face.png"];
}
[[cell.contentView subviews] makeObjectsPerformSelector:#selector(removeFromSuperview)];
cell.contentView = imageView;
}
return cell;
}
I think that the problem may be you are removing the cell using makeObjectsPerformSelector and then it'll never be added again after removing since the control may not enter into the condition if (!cell) {} due to the presence of the instance cell.
Hope this helps you.
So I have some issues with my tableview. I have a custom label that I put into a tableview cell to add a little better graphics than the standard UItableviewcell. However, I was running into my first problem,
the text labels that I had on the cells were changing with and over writing each other upon scrolling, only when the cells had moved off screen and then came back. Upon some research I found that maybe it had something to do with dequeueReusableCellWithIdentifier: so I adjusted my code. this is where problem two comes in.
When I load the table everything is in its right place, correct looking and all. However when I start to scroll down I can get to all of my cells except the last one, it will go to the very bottom of the 8th cell and freeze, but I should have 9 cells loaded.
I am quite confused by some of this, could anyone provide some code or guidance to help me along?
Thanks.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
NSLog(#"Run");
CoCoachAppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];
static NSString *CellIdentifier = #"Cell";
UILabel *label;
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
NSArray *keys = [[appDelegate rowersDataStore] allKeys];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
// Configure the cell...
label = [[[UILabel alloc] initWithFrame:CGRectMake(20, 15, cell.bounds.size.width - 10, 30)] autorelease];
label.font = [UIFont boldSystemFontOfSize:16];
label.backgroundColor = [UIColor clearColor];
label.shadowColor = [UIColor colorWithWhite:1.0 alpha:0.5];
label.shadowOffset = CGSizeMake(0,1);
label.textColor = [UIColor colorWithRed:0x4c/255.0 green:0x4e/255.0 blue:0x48/255.0 alpha:1.0];
switch (indexPath.section) {
case 0:
label.frame = CGRectMake(0, 15, cell.bounds.size.width - 10, 30);
label.textAlignment = UITextAlignmentCenter;
break;
case 1:
label.textAlignment = UITextAlignmentLeft;
UIImage *accessoryImage = [UIImage imageNamed:#"content_arrow.png"];
UIImageView *accessoryView = [[UIImageView alloc] initWithImage:accessoryImage];
cell.accessoryView = accessoryView;
[accessoryView release];
break;
}
UIImageView *imgView = [[UIImageView alloc] initWithFrame:cell.frame];
UIImage* img = [UIImage imageNamed:#"odd_slice.png"];
imgView.image = img;
cell.backgroundView = imgView;
[imgView release];
//Selected State
UIImage *selectionBackground = [UIImage imageNamed:#"row_selected.png"];
UIImageView *selectionView = [[UIImageView alloc] initWithFrame:cell.frame];
selectionView.image = selectionBackground;
cell.selectedBackgroundView = selectionView;
[selectionView release];
}
switch (indexPath.section) {
case 0:
[label setText:#"Click to add new rower"];
break;
case 1:
[label setText:[[[appDelegate rowersDataStore] objectForKey:[keys objectAtIndex:indexPath.row]] objectForKey:#"Name"]];
break;
}
//Adds Text
[cell addSubview:label];
return cell;
}
I see several issues here. First, the general structure of this method should be...
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
// Attempt to dequeue the cell
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
// If cell does not exist, create it, otherwise customize existing cell for this row
if (cell == nil) {
// Create cell
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
// Configure cell:
// *** This section should configure the cell to a state independent of
// whatever row or section the cell is in, since it is only executed
// once when the cell is first created.
}
// Customize cell:
// *** This section should customize the cell depending on what row or section
// is passed in indexPath, since this is executed every time this delegate method
// is called.
return cell;
}
Basically, UITableView uses a single UITableViewCell instance to draw every cell in the table view. So, when you first create this cell, you should configure it to a state that is common to all cells that will use this instance, independent of whatever row or section is passed in indexPath. In your example, this involves creating the label, image, and background image instances and adding them as subviews to the cell.
Once the cell is created (aka outside the if (cell == nil) statement), you should customize its properties according to how the cell should look for the specific row and section contained in indexPath. Since you want to access your custom label in this part of the code, I assigned a tag value to it so that we can access it beyond the code segment where it was created using viewWithTag:. Once we have the label, we can customize it according to the section as well as do anything else we want, such as customize the accessory view.
I slightly modified/cleaned up your code below. This is by far not the most efficient or elegant way to do what you want to do, but I was trying to keep as much of your code as possible. I haven't tested this, but if you try it it should work:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
NSLog(#"Run");
CoCoachAppDelegate *appDelegate = [[UIApplication sharedApplication] delegate];
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
NSArray *keys = [[appDelegate rowersDataStore] allKeys];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
// Configure the cell...
UILabel *label;
label = [[[UILabel alloc] initWithFrame:CGRectMake(20, 15, cell.bounds.size.width - 10, 30)] autorelease];
label.font = [UIFont boldSystemFontOfSize:16];
label.opaque = NO;
label.backgroundColor = [UIColor clearColor];
label.shadowColor = [UIColor colorWithWhite:1.0 alpha:0.5];
label.shadowOffset = CGSizeMake(0,1);
label.textColor = [UIColor colorWithRed:0x4c/255.0 green:0x4e/255.0 blue:0x48/255.0 alpha:1.0];
label.tag = 100;
[cell addSubview:label];
[label release];
UIImageView *imgView = [[UIImageView alloc] initWithFrame:cell.frame];
UIImage* img = [UIImage imageNamed:#"odd_slice.png"];
imgView.image = img;
cell.backgroundView = imgView;
[imgView release];
//Selected State
UIImage *selectionBackground = [UIImage imageNamed:#"row_selected.png"];
UIImageView *selectionView = [[UIImageView alloc] initWithFrame:cell.frame];
selectionView.image = selectionBackground;
cell.selectedBackgroundView = selectionView;
[selectionView release];
}
UILabel *lbl = (UILabel *)[cell viewWithTag:100];
switch (indexPath.section) {
case 0:
cell.accessoryView = nil;
lbl.frame = CGRectMake(0, 15, cell.bounds.size.width - 10, 30);
lbl.textAlignment = UITextAlignmentCenter;
[label setText:#"Click to add new rower"];
break;
case 1:
UIImage *accessoryImage = [UIImage imageNamed:#"content_arrow.png"];
UIImageView *accessoryView = [[UIImageView alloc] initWithImage:accessoryImage];
cell.accessoryView = accessoryView;
[accessoryView release];
lbl.frame = CGRectMake(20, 15, cell.bounds.size.width - 10, 30);
lbl.textAlignment = UITextAlignmentLeft;
[lbl setText:[[[appDelegate rowersDataStore] objectForKey:[keys objectAtIndex:indexPath.row]] objectForKey:#"Name"]];
break;
}
return cell;
}
First question on this site, although I have been around for a while behind the scenes. I have a problem that I have been racking my head on for the last two days and I hope someone can shed some light on it for me.
I have a UITableView, which is loaded from a SQL database. It has 15 entries in it. I have inserted an extra cell at the beginning of the UITableView. This extra cell is for a UITextField and UIButton which adds an item into the database.
When the view is loaded, the first cell with the custom objects shows fine, and the rest of the table is filled with items from the database and looks just how it should. However, when the UITableView is scrolled down so the first cell is out of view, then back up, it takes the value of the 11th row item and shows it over top the first cell.
Here is my code:
- (UITableViewCell *)tableView:(UITableView *)popTableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
static NSInteger NameTag = 1;
UITableViewCell *cell = [popTableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:CellIdentifier] autorelease];
CGRect frame;
frame.origin.x =50;
frame.origin.y =10;
frame.size.height =22;
frame.size.width =275;
UILabel *nameLabel = [[UILabel alloc] initWithFrame:frame];
nameLabel.tag = NameTag;
nameLabel.opaque = YES;
nameLabel.textColor = [UIColor grayColor];
nameLabel.backgroundColor = [UIColor clearColor];
[cell.contentView addSubview:nameLabel];
[nameLabel release];
}
int row = [indexPath row];
if (row == 0) {
UIButton *buttonLeft = [UIButton buttonWithType:UIButtonTypeCustom];
[buttonLeft setFrame: CGRectMake( 205, 6, 40, 33)];
[buttonLeft addTarget:self action:#selector(addToList:) forControlEvents:UIControlEventTouchUpInside];
[cell addSubview:buttonLeft];
//No Alloc for txtField, it is built in IB
[txtField setBorderStyle:UITextBorderStyleNone];
[txtField setFrame: CGRectMake( 17, 12, 180, 23)];
txtField.backgroundColor = [UIColor clearColor];
[txtField addTarget:self action:#selector(textFieldDidChange:) forControlEvents:UIControlEventEditingChanged];
txtField.clearButtonMode = UITextFieldViewModeAlways;
}else{
UILabel * nameLabel = (UILabel *) [cell.contentView viewWithTag:NameTag];
Add *theObj = [self.theArray objectAtIndex:indexPath.row - 1];
[nameLabel setText:theObj.itemName];
cell.selectionStyle = UITableViewCellSelectionStyleNone;
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
UIImageView *imageView = [cell viewWithTag:kTagCellImageView];
if (imageView == nil) {
imageView = [[UIImageView alloc]initWithFrame:CGRectMake(10.0, 10.0, 13.0, 25.0)];
imageView.backgroundColor = [UIColor clearColor];
imageView.tag = kTagCellImageView;
[cell.contentView addSubview:imageView];
}
if([theObj.itemName isEqualToString:#"First Street"]){
imageView.frame = CGRectMake(14,10,13,25);
[imageView setImage:[UIImage imageNamed:#"firststreet"]];
}
else if([theObj.itemName isEqualToString:#"Second Street"]){
imageView.frame = CGRectMake(8,12,29,20);
[imageView setImage:[UIImage imageNamed:#"second"]];
}
else if([theObj.itemName isEqualToString:#"Main Street"]){
imageView.frame = CGRectMake(15,10,13,25);
[imageView setImage:[UIImage imageNamed:#"mainstreet"]];
}
else{
imageView.frame = CGRectMake(8,8,25,25);
[imageView setImage:[UIImage imageNamed:#"iconcustom"]];
}
NSLog(#"%#",itemName);
NSLog(#"%#",itemCategory);
}
return cell;
}
Also here is my cellForRow:
- (NSInteger)tableView:(UITableView *)popTableView numberOfRowsInSection:(NSInteger)section {
return [self.theArray count] + 1; //Add Extra cell to beginning
}
Any ideas would be greatly appreciated.
You need to use a different reuseIdentifier for your first cell. Try this:
NSString *cellIdentifier;
if (indexPath.row == 0) {
cellIdentifier = #"first";
} else {
cellIdentifier = #"not first";
}
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier] autorelease];
// .. cell initialization
}
Obligatory tangential answer - have you thought about setting the tableHeaderView on the UITableView instead? I think that'd accomplish what you're trying to do in a cleaner way (in that it adds an arbitrary view to the top of the table).
Just create a UIView with your "add a new item" controls in it and then set it as the header view when first creating the table.
The issue is here
static NSString *CellIdentifier = #"Cell";
static NSInteger NameTag = 1;
UITableViewCell *cell = [popTableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:CellIdentifier] autorelease];
you are dequeueing all of the cells with the same identifier. Row 1 (index 0) needs to have its own CellIdentifier. Also it looks like you keep adding subviews to the same cells that you dequeue. On your if(cell == nil) check you may want to decide if you want to remove all of the cells contentView subviews or reuse them.
Here's what I need to do:
Load 66px x 66px images into the table cells in the MainViewController table.
each TableCell has a unique image.
But how? Would we use cell.image?
cell.image = [UIImage imageNamed:#"image.png"];
If so, where? Is an if/else statement required?
To load each cell's labels, MainViewController uses an NSDictionary and NSLocalizedString like so:
//cell one
menuList addObject:[NSDictionary dictionaryWithObjectsAndKeys:
NSLocalizedString(#"PageOneTitle", #""), kTitleKey,
NSLocalizedString(#"PageOneExplain", #""), kExplainKey, nil]];
//cell two
menuList addObject:[NSDictionary dictionaryWithObjectsAndKeys:
NSLocalizedString(#"PageOneTitle", #""), kTitleKey,
NSLocalizedString(#"PageOneExplain", #""), kExplainKey, nil]];
...
// this is where MainViewController loads the cell content
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
MyCustomCell *cell = (MyCustomCell*)[tableView dequeueReusableCellWithIdentifier:kCellIdentifier];
if (cell == nil)
{
cell = [[[MyCustomCell alloc] initWithFrame:CGRectZero reuseIdentifier:kCellIdentifier] autorelease];
}
...
// MyCustomCell.m adds the subviews
- (id)initWithFrame:(CGRect)aRect reuseIdentifier:(NSString *)identifier
{
self = [super initWithFrame:aRect reuseIdentifier:identifier];
if (self)
{
// you can do this here specifically or at the table level for all cells
self.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
// Create label views to contain the various pieces of text that make up the cell.
// Add these as subviews.
nameLabel = [[UILabel alloc] initWithFrame:CGRectZero]; // layoutSubViews will decide the final frame
nameLabel.backgroundColor = [UIColor clearColor];
nameLabel.opaque = NO;
nameLabel.textColor = [UIColor blackColor];
nameLabel.highlightedTextColor = [UIColor whiteColor];
nameLabel.font = [UIFont boldSystemFontOfSize:18];
[self.contentView addSubview:nameLabel];
explainLabel = [[UILabel alloc] initWithFrame:CGRectZero]; // layoutSubViews will decide the final frame
explainLabel.backgroundColor = [UIColor clearColor];
explainLabel.opaque = NO;
explainLabel.textColor = [UIColor grayColor];
explainLabel.highlightedTextColor = [UIColor whiteColor];
explainLabel.font = [UIFont systemFontOfSize:14];
[self.contentView addSubview:explainLabel];
//added to mark where the thumbnail image should go
imageView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 66, 66)];
[self.contentView addSubview:imageView];
}
return self;
}
If the image is going to be the same for every cell, i.e., it's part of that type of cell, you could load it in MyCustomCell's init, using self.image = [UIImage imageNamed:"blabla"];
Otherwise, if the image will be different for different cells, it would be more logical to put it in tableView:cellForRowAtIndexPath:
Yes, cell.image is deprecated. use imageview.image instead in the default TableViewCell. I am not sure why custom cell was required to do what the standard tableviewcell already does (title, subtitle, and an image using UITableViewStyleSubtitle)
It works now. You were right, Seventoes, about putting it in tableView:cellForRowAtIndexPath:
indexPath.row was what I was I missing. The working result goes like this:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
MyCustomCell *cell = (MyCustomCell*)[tableView dequeueReusableCellWithIdentifier:kCellIdentifier];
if (cell == nil)
{
cell = [[[MyCustomCell alloc] initWithFrame:CGRectZero reuseIdentifier:kCellIdentifier] autorelease];
}
if (indexPath.row == 1)
{
cell.image = [UIImage imageNamed:#"foo.png"];
}
else if (indexPath.row == 2)
cell.image = [UIImage imageNamed:#"bar.png"];
}
...
else
{
cell.image = [UIImage imageNamed:#"lorem.png"];
}
return.cell;
}
A better approach then that if-else mess would be to push your images onto a NSMutableArray in the right order, and then just use
cell.image = [myImages objectAtIndex:indexPath.row];