I have a table with a few rows, and the place holder text for all is the same. How can I programmatically change the placeholder text of only the first one?
Thanks!
You need to run an if statement to check the index of the cell. 0 is the first index, so you would need to check to see if the row is 0.
- (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];
}
if (indexPath.row == 0)
cell.textLabel.text = #"First Cell";
else
cell.textLabel.text = #"Not First Cell";
}
In order to access your cell AFTER the cell was created/reused, try the - (UITableViewCell *)cellForRowAtIndexPath:(NSIndexPath *)indexPath method of your uitableview object! See the following Apple doc for a detailed elaboration on this method.
Note:
Return Value
An object representing a cell of the table or nil if the cell is not
visible or indexPath is out of range.
Related
I have a UITableView with a custom cell using Storyboards. All the objects inside the custom cell work but when I scroll in my UITableView the objects do not move:
Here is my code:
- (UITableViewCell *)tableView:(UITableView *)tableview cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"MainCell";
MainCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[MainCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
cell.subtitle.text = [NSString stringWithFormat:#"%#",theEvent.startDate];
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
return cell;
}
Any ideas on what I have done wrong? Thanks.
I figured out the problem. The objects that I had placed on the UITableViewCell were not actually inside the cell but on top of the UITableView and therefore they were acting as "floating" objects.
Hey I'm having trouble trying to figure this one out. UITableView has a method [tableView reloadSections:(NSIndexSet *) withRowAnimation:(UITableViewRowAnimation)] now according to the Apple docs this method takes in an NSIndexSet object and reloads what ever section specified by the index set. The problem is even though im only sending in one section to this method it ends up reloading all the sections and i can't understand why this is happening. Any help will be greatly appreciated
Even if you try reloading only a section, you must also provide the populating process section by section:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"DetailViewCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:CellIdentifier] autorelease];
cell.selectionStyle = UITableViewCellSelectionStyleNone;
}
if (indexPath.section == 0){
//blablabla
cell.textLabel = blabla
}
else if (indexPath.section == 1){
///blablabla
cell.textLabel = blabla2
}
return cell;
}
... because reloading the table (is it only a section or the whole table) wil call the method above
I have created sample application that insert 12 rows in tableview.And inserted fine.When after inserted my rows i dont want any changes in text during scrolling of tableview.So i checked with indexpath row has value of UITableViewCell , if it has values means return that cell otherwise we created new UITableViewCell.
My sample code is below
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
return 1;
}
// Customize the number of rows in the table view.
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
NSLog(#"GlobalCount = %d",GlobalCount);
return GlobalCount;
}
- (UITableViewCell *)tableView:(UITableView *)tv cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *obj = (UITableViewCell*)[tableView cellForRowAtIndexPath:indexPath];
if(obj!=nil)
{
NSLog(#"cell indexpath row = %d",indexPath.row);
NSLog(#"cell text = %d",obj.textLabel.text);
return obj;
}
else {
NSLog(#"obj==nil");
}
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tv dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
cell.selectionStyle = UITableViewCellSelectionStyleNone;
}
if([DataTable count]>0)
cell.textLabel.text = [DataTable objectAtIndex:0];
// Configure the cell.
return cell;
}
What my objective is , i dont want update any text (or UITableViewCell)for already created indexpath rows(of cell).So i can check this in cellForRowAtIndexPath , but it always return nil.If i am missing anything ?
I checked using this line
UITableViewCell *obj = (UITableViewCell*)[tableView cellForRowAtIndexPath:indexPath];
if(obj!=nil)
Plz help me?
Thanks in advance......
Let the table view decide id it need to update the cell or not. Just remove all the firsdt part of your code and everything will run smoothly.
Don't hesitate to read the UITableView doc.
I just have a basic (noob) question about cellForRowAtIndexPath get called?
I'm working through example code and I don't see it explicitly called anywhere?
Does any component of type UITableViewComponent automatically call this function when it is created?
Thanks
When a UITableView is displaying this method gets called per row. In it you will customize each cell with particular data for display.
Here's the class reference.
Here's a sample:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"FriendCellIdentifier";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier] autorelease];
}
NSUInteger row = [indexPath row];
cell.accessoryType = UITableViewCellAccessoryDetailDisclosureButton;
Item *i = [itemArray objectAtIndex:row];
cell.textLabel.text = [i name];
cell.detailTextLabel.text = [i brewery];
[i release];
return cell;
}
This is called for each cell when the corresponding UITableView gets drawn. An index path is passed in, and based on the section and cell numbers, your code should generate a UITableViewCell to be displayed in the UI.
You can look here for a quick tutorial into how UITableViews work.
I want to make a table view in my iPhone Application.. In that table each shall contains 1 image, some text of line, some symbols, etc.. I don't now how to customize our cell of table. Please provide some help if you have..
I think you can use a default UITableViewCell to do what you described by initializing the Cell (in - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath ) with the proper UITableViewCellStyle
e.g.:
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier] autorelease];
}
// Set up the cell...
return cell;
}
which gives you:
"A style for a cell with a left-aligned label across the top and a left-aligned label below it in smaller gray text. The iPod application uses cells in this style."
Also every kind of UITableViewCell has an image-property by default.
but here are some tutorials for building custom cells:
Custom UITableViewCells with Interface Builder
http://iphone.zcentric.com/2008/08/05/custom-uitableviewcell/
You can create a cell in Interface Builder. Start with a UITableViewCell which acts like a view, and then add a UIImage, one or more labels, whatever containers to hold your symbols, etc.
Then in your cellForRowAtIndexPath, load the nib and fill in the picture and labels, etc.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
MyTableCell *cell = (MyTableCell *) [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = myTableCell; // get the object from the outlet
myTableCell = nil; // make sure this can't be re-used accidentally
}
// Set up the cell...
cell.myViewController = self;
// set up image and labels here
return cell;
}