I'm loading an image in to an UITableView through a simple
cell.imageView.image = [UIImage imageNamed:#"prem.jpg"];
However, what I've learnt from my limited time with xcode things arent normally that easy! I want to have the image in there take up the fullsize of the image which is about 280 wide and 150 tall. From googling I might have to build a custom cell and put the image in there and then load that custom cell? I've not done anything like that before and it seems a bit annoying just to load one image. Is there an alternative?
To put in context, I have 3 sections in the tableview top section will be the image, and the other two are arrays loaded from XML files. If I do a custom cell I have to do a seperate xml call to get the image url before it goes through so I'd really like to avoid that if possible?
Really looking for any pointers you can offer. Thanks a lot
Tom
Edit: cellforrowindexpath as requsted:
(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:CellIdentifier] autorelease];
}
if(indexPath.section == 0)
cell.imageView.image = [UIImage imageNamed:#"prem.jpg"];
if(indexPath.section == 1)
cell.textLabel.text = [arryTableData objectAtIndex:indexPath.row];
else if(indexPath.section == 2)
cell.textLabel.text = [arryTableActions objectAtIndex:indexPath.row];
return cell;
}
There is no need to create a custom cell subclass. I am assuming you have a single cell in section 0 and a variable number of cells in sections 1 and 2.
You should be using a different cell reuse identifier for your cell in section 0 as it contains an image view and the others don't - this will show up in your later sections when the cells are recycled otherwise.
I'd try something like this:
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifierText = #"TextCell";
static NSString *CellIdentifierImage = #"ImageCell";
if (indexPath.section == 0)
{
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifierImage];
// I am assuming this image never changes and there is one row in this section! If it does change, use viewWithTag to get hold of the image view.
if (cell == nil)
{
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifierImage] autorelease];
UIImageView *myImageView = [[UIImageView alloc] initWithFrame:CGRectMake(0,0,250,180)];
myImageView.tag = 1;
myImageView.image = [UIImage imageNamed:#"prem.jpg"];
[cell addSubview:myImageView];
[myImageView release];
}
return cell;
}
else
{
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifierText];
if (cell == nil)
{
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifierText] autorelease];
}
if(indexPath.section == 1)
cell.textLabel.text = [arryTableData objectAtIndex:indexPath.row];
else if(indexPath.section == 2)
cell.textLabel.text = [arryTableActions objectAtIndex:indexPath.row];
return cell;
}
}
Make sure you are adding the image to the newly created image view and not cell.imageView as the latter is a read-only property which is over to the left side, I'm not sure you can resize it.
You will also need to set the height for your cell, as it is taller than the standard. This will be in the tableView:heightForRowAtIndexPath: delegate method.
you can use the customCells.Means take an image view (whatever size you want.).And add it to the cell in cellforIndexpath method.
Related
In a normal situation when working with a UITableView I have the standard code for reusing old cells:
- (UITableViewCell *)tableView:(UITableView *)tv cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *cellIdentifier = #"Cell";
UITableViewCell *cell = [tv dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell == nil)
{
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
}
return cell;
}
I noticed, however, that in the case when I added subviews to the cell that they weren't deleted and that a new view were added every time. I have an example below that demonstrate it perfectly:
- (UITableViewCell *)tableView:(UITableView *)tv cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *cellIdentifier = #"Cell";
UITableViewCell *cell = [tv dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell == nil)
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
UILabel *label = [[UILabel alloc] init];
label.text = #"HELLO";
label.frame = CGRectMake(arc4random() % 50, -1, 286, 45);
label.backgroundColor = [UIColor clearColor];
// Add views
[cell addSubview:label];
return cell;
}
I need some code that reuses my labels again in the same way the cells are being reused. What should I do?
Thanks
You must only add the subviews if you are making a new cell. If you are dequeuing, the subview is already present and should not be re-created.
Your method should be:
- (UITableViewCell *)tableView:(UITableView *)tv cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *cellIdentifier = #"Cell";
UITableViewCell *cell = [tv dequeueReusableCellWithIdentifier:cellIdentifier];
UILabel *label;
if (cell == nil)
{
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
label = [[UILabel alloc] init];
label.tag = 1;
// Add views
[cell addSubview:label];
}
else
{
// Label will already exist, get a pointer to it
label = [cell viewWithTag:1];
}
// Now set properties on the subview that are unique to each cell
label.text = #"HELLO";
label.frame = CGRectMake(arc4random() % 50, -1, 286, 45);
label.backgroundColor = [UIColor clearColor];
return cell;
}
Note how the label is only created when the cell is nil. Otherwise, it is found using the tag.
I need some code that reuses my labels again in the same way the cells
are being reused.
No, you need to understand the table view design better. It should be obvious why the views are being added multiple times – reusing a cell means that you take a previous instance of UITableViewCell that’s no longer needed (thus saving a costly allocation of a new object) and reuse this instance for the new cell. But this previous instance already has the label attached to it, so the number of labels grows.
I would subclass UITableViewCell and put the label creation inside the initialization code for this new class. (Or create a UIView subclass and set it as the cell’s contentView, as suggested in this nice table tutorial by Matt Gallagher.) That’s the proper way to encapsulate the view details and hide them from the table data source.
you can use something like in the else part for if(cell == nil)
for (UIView *sub in [cell.contentView subviews])
{
if([UILabel class] == [sub class])
NSLog(#"%#",[sub class]);
UILabel *label = (UILabel *)sub;
//do label coding ie set text etc.
}
I use lazy initialization of views within my custom table cell class.
It only needs to load views and "addSubview" once.
- (void) lazyInitTitleLabel {
if (_titleLabel != nil) {
return;
}
_titleLabel = [[UILabel alloc] initWithFrame: CGRectMake(10.0f, 10.0f, 200.0f, 30.0f)];
// Cell adds the label as a subview...
[self addSubview: _titleLabel];
}
The only thing you need to be careful about is resetting any content that views display like text in your labels and images in your image views. If you don't old content may get reused along with the recycled table cells.
Good luck!
I want tableView not to load a cell that contains some string, how to do that?
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier] autorelease];
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
}
NSString *itemTitle = item.title;
if ([item.title isEqualToString: #"Some string"])
{
// Help needed
}
else
{
cell.textLabel.font = [UIFont boldSystemFontOfSize:15];
cell.textLabel.text =itemTitle;
}
return cell;
One possible option can be you save indexPath of cell that you don't want to show on screen when table is being loaded and once loading is completed delete them form table using following method.
- (void)deleteRowsAtIndexPaths:(NSArray *)indexPaths withRowAnimation:(UITableViewRowAnimation)animation
Better option is to update your data before providing loading the table.
If both of above fails then you can try following method
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
Return 0 if you don't want cell to appear on screen. Probably cell with height 0 will not appear.
If above don't work then post here so that i can assist further....
Hey guys i have a table view that can add and delete cells. but when i delete the only cell that comes with the app, and i try to add a new cell with the text of "Meghan Way" and the text just automatically changes it self to the original cells text which is "House 1" here is my code!
- (IBAction)saveButton:(id)sender {
FacePlatesViewController * viewController = (FacePlatesViewController
*)self.parentViewController;
[viewController addObject:[NSMutableDictionary dictionaryWithObject:text.text
forKey:#"name"]];
[self dismissModalViewControllerAnimated:YES];
}
- (IBAction)cancel:(id)sender {
[self dismissModalViewControllerAnimated:YES];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:
(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero
reuseIdentifier:CellIdentifier] autorelease];
cell.textLabel.text = [[cells objectAtIndex:indexPath.row] valueForKey:#"name"];
UIImage * myimage = [UIImage imageNamed: #"check.png"];
image = [[UIImageView alloc]initWithImage:myimage];
tableView.backgroundColor = [UIColor clearColor];
self.myTableView = tableView;
}
return cell;
}
this is for the save button! any help would be very appreciated:D Thanks
You code is quite messed up. I have improved it below and added comments:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:
(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil)
{
cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero
reuseIdentifier:CellIdentifier] autorelease];
} //The if block should end here. You should set the cell's label irrespective whether the cell was nil. This is the cause of the issue you are facing.
cell.textLabel.text = [[cells objectAtIndex:indexPath.row] valueForKey:#"name"];
//You are doing nothing with the UIImage
//UIImage * myimage = [UIImage imageNamed: #"check.png"];
//image = [[UIImageView alloc]initWithImage:myimage];
//You should be setting the background color just once, in ViewDidLoad, not here.
//tableView.backgroundColor = [UIColor clearColor];
//I don't see why this is required
//self.myTableView = tableView;
return cell;
}
Are you storing the text labels for these cells in any kind of array or dictionary and loading them in there using the standard "cellForRowAtIndexPath?" If so, then you need to delete the dictionary / array entry in that data source to prevent it from being used again.
I can't tell for sure without seeing some more code...but it sounds like a cell recycling issue. I could be wrong...but I'd need to see more info.
I have a segmented tableView that loads all the data in all the cells of all the sections.
There is a textField in each cell.
The tableview doesn't fit the iPad screen completely, and I can't access all the invisible cells in order to read/save data. And when I make changes in "textField", then scroll up, the scroll down, all the changes are gone.
I need to load all the cells, even invisible once, to be able to access them.
I am sorry, I just started working with tables a few days ago...
I think that this problem has something to do with reusable cells, but not sure how to resolve it.
Looking for your help, please.
initialization:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [self.tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
UITextField *textField = [[UITextField alloc] initWithFrame:CGRectMake(0, 0, 400, 30)] ;
textField.enabled = NO;
cell.accessoryView = textField;
[textField release];
}
UITextField *textField = (UITextField*)cell.accessoryView;
if(indexPath.section == 0)
cell.textLabel.text = [idenInfo objectAtIndex:indexPath.row];
else if (indexPath.section == 1)
cell.textLabel.text = [prodInfo objectAtIndex:indexPath.row];
else if (indexPath.section == 2)
cell.textLabel.text = [visInfo objectAtIndex:indexPath.row];
if(indexPath.section == 0)
textField.text = [idenInfoRez objectAtIndex:indexPath.row];
else if (indexPath.section == 1)
textField.text = [prodInfoRez objectAtIndex:indexPath.row];
else if (indexPath.section == 2)
textField.text = [visInfoRez objectAtIndex:indexPath.row];
textField = nil;
return cell;
}
First of all : you don't have to load all the cells including the invisible ones. That's the whole point of the UITableView and MVC Pattern : separate your views from your data.
What you'll want to do is update your Data source (that is idenInfoRez, prodInfoRez and vizInfoRez in your case) when the user has changed a value inside a textField. So you'll have to set your UIViewController as the delegate of each textfield and update the values as the user types in.
[UIView beginAnimations:#"ShiftUp" context:nil];
[UIView setAnimationDuration:0.0001];
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
NSInteger section = [indexPath section];
static NSString *CellIdentifier = #"Cell";
CustomCell *cell = (CustomCell *)[tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
[[NSBundle mainBundle] loadNibNamed:#"CustomCell" owner:self options:nil];
cell = objCustCell;
cell.selectionStyle = UITableViewCellSelectionStyleNone ;
}
if (section == 0) {
switch (indexPath.row) {
case 0:{
cell.lable.text = #"Date of Birth";
cell.field.placeholder = #"Birth Name";
break;
}
case 1:{
cell.lable.text = #"Enter Your Name";
cell.field.placeholder = #"Full Name";
break;
}
default:
break;
}
}
[UIView beginAnimations:#"ShiftUp" context:nil];
[UIView setAnimationDuration:0.0001];
// [UIView beginAnimations: #"ShiftUp" context:nil];
NSLog(#"Load cellfor raw at index ");
// Configure the cell.
return cell;
}
Note : UIView animation will not allow text field to move away data or any UIcontroller will remain same in its old state !!
Don't Commit animation otherwise it will not working !!
What you can do is this: in the Editing Changed event of each of the TextField store the value contain in the text field in an NSMutableArray whose number equal the number of cells. i.e.
-(IBAction) EditingChanged: (id) sender
{
UITextField *txt =(UITextField*)sender;
NSString* str =[[NSString alloc] initWithString: txt.text];
//get current text string
NSInteger path =[tableView indexPathForSelectedRow].row;
// get currently selected row, this could be a bit different depending on the number of sections
[yourMutableArray insertObject: str atIndex: path];
[str release]
}
You can then populate the TextField with the values from the NSMutableArray anytime the cells are recreated i.e.
(UITableViewCell *) tableView: (UITableView*)tableView cellForRowAtIndexPath:(NSIndexPath*) indexPath
{
...... // create the cells here and use viewTag to get the textFields
textField.text= [yourMutableArray objectAtIndex:indexPath.row];
//This may be a bit different depending on the number of sections.
}
Also, note that it might be advisable to initialize yourMutable array to the capacity of the number of cells.
I am sorry if the codes are not well formatted as this is my first post on stackoverflow - also there might be some typos in the code. Hope this helps someone.
every time we allocate the cell to different data,the data will not reloading the cell,every time the data override previous data, before allocate the cell to clear cell,
like as cell=nil
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [self.tableView dequeueReusableCellWithIdentifier:CellIdentifier];
cell=nil;
//it clear data in the cell
if (cell == nil)
{
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
UITextField *textField = [[UITextField alloc] initWithFrame:CGRectMake(0, 0, 400, 30)] ;
textField.enabled = NO;
cell.accessoryView = textField;
[textField release];
}
You're right, the problem is the cells will be reused. There are two solutions to the problem, the quick and dirty one would be to not use reusable cells:
Remove this:
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [self.tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
And just leave this:
UITableViewCell * cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
UITextField *textField = [[UITextField alloc] initWithFrame:CGRectMake(0, 0, 400, 30)] ;
textField.enabled = NO;
cell.accessoryView = textField;
[textField release];
That should be ok, if you have only a small number of cells in your tableview (about fewer than 50).
The better solution would be to leave cell reuse on, and fill their textfields as they are requested. The approach differs from app to app, but you basically never should access the cells directly, and store the data of the cell somewhere else, e.g. an NSArray of NSStrings. You could then manipulate the NSArray. Your cellForRowAtIndexPath method would look something like this:
textField.text = [arrData objectAtIndex:indexPath.row];
I'm having one Table view. In that i want to set the color for the First cell alone..Others should be in white...How can i do that
I need your help....
Thanks in advance.....
In cellForRowAtIndexPath, check if the indexPath.row == 0, then set the custom background. Otherwise set the default background.
// Customize the appearance of table view cells.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
}
// Configure the cell...
if (indexPath.row == 0) {
//set custom background color
} else {
//set default background color
}
return cell;
}
You should do the color change in the "willDisplayCell" delegate method and not at its creation in "cellForRowAtIndexPath".
Otherwise it may not stick or may display bad when adding, for example, accessories to the cell.
Look at this post for more details : Setting background color of a table view cell on iPhone
if(indexPath.row == 0)
{
UIView *bg = [[UIView alloc] initWithFrame:cell.frame];
bg.backgroundColor = [UIColor colorWithRed:175.0/255.0 green:220.0/255.0 blue:186.0/255.0 alpha:1];
cell.backgroundView = bg;
[bg release];
}