How can i access a tableview cell directly to edit the detail text?
I've tryed it like this:
UITableViewCell *cell = [self.tableView cellForRowAtIndexPath:self.selectedTablePath];
cell.detailTextLabel.text = [[[self.thePicker objectAtIndex:0] valueForKey:#"country"] objectAtIndex:row];
The self.selectedTablePath variable is set in the didSelectRowAtIndexPath function and is a NSIndexPath.
If i try it like above, i get the error Expected expression.
Related
just created an UITableView,
trying to display some custom data from an array, but what ever I do, i get no text displayed.
NSLog tell me the right text and right amout but no text in table cell.
here is the code:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:CellIdentifier];
}
cell.textLabel.text = #"test";
[self configureCell:cell atIndexPath:indexPath];
return cell;
}
Things to check:
Is cellForRowAtIndexPath getting called? Put a breakpoint in
Make an array in ViewDidLoad (property, alloc'd) and addObjects #"One", #"Two", #"Three", nil and then cell.textLabel.text = [theArray objectAtIndex:indexPath.row];
IfcellForRow is being called, this will show in the cells.
What doesConfigureCell do? Include the code please.
Also check your tableView delegate methods are being called (NumberofRowsInSection etc)
Always set cell properties (text, images, accessory views, etc) in the
tableView:willDisplayCell:forRowAtIndexPath
delegate method.
UITableView sometimes send a prepareForReuse to the cell after it is returned from
tableView:cellForRowAtIndexPath
which causes the cell to reset it's labels and images.
In my tableview have custom cells that I initialize from a UITableViewCell class. I have sections for first letters of records and have an indexPath that is being created dynamically.
I wanted to add a search display controller to my tableview. So I did, created all methods to filter data. I am sure that my functions are working well because I am printing array count to screen for search results.
My problem is that the first time view loads, the data is on the screen. But when I hit the search input and type a letter, than I get 'UITableView dataSource must return a cell from tableView:cellForRowAtIndexPath:' error. After I used a breakpoint I saw that my custom cell is nil after searching. Data is exist, but cell is not being initialized.
Here is the code I use for custom cell initializing:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"ObjectCell";
SpeakerCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
NSDictionary *myObject = [[sections valueForKey:[[[sections allKeys] sortedArrayUsingSelector:#selector(localizedCaseInsensitiveCompare:)] objectAtIndex:indexPath.section]] objectAtIndex:indexPath.row];
cell.label1.text = [myObject objectForKey:#"myValue"];
return cell;
}
I believe I made a mistake when putting controls in IB. So I added screenshots of objects:
Connections inspector for my table view
Connections inspector for my search display controller
EDIT: Problem is actually solved, I have used a UISearchBar instead of Search Display Controller but I guess this issue remains unsolved. So I'm willing to try any ways to make it work.
As of here search display controller question,
you need to access the self.tableView instead of tableView:
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
UITableViewCell *cell = [self.tableView dequeueReusableCellWithIdentifier:#"CellId"];
// do your thing
return cell;
}
For those using iOS 5 and StoryBoards, you would want to use the following method instead of initWithIdentifier:
initWithStyle:(UITableViewCellStyle)stylereuseIdentifier:(NSString *)reuseIdentifier
Example:
NSString *cellIdentifier = #"ListItemCell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
}
I'm not sure about how this should work in storeboarding.
But normally you would check if the [tableView dequeueReusableCellWithIdentifier:CellIdentifier] returns a cell.
Because if the cell in not loaded before or there aren't any cells to reuse you will have to create a new cell:
SpeakerCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[SpeakerCell alloc] initWithIdentifier: CellIdentifier];
}
Also when in declaring local variables in Objective-C we tent not to capitalize the first letter.
I had the same issue, with custom cells (built in Storyboard) not being drawn as soon as the first letter was put in the search field. The search was successful however.
Finally I found a good tutorial from Brenna Blackwell suggesting to configure manually the cell drawing in the corresponding subclass of UITableViewCell, adding UILabels and other items.
Normally in a UITableView, we assign the value for the cells in the cellForRowAtIndexPath method which is the delegate method of UITableView. In this case, if we use a CustomTableViewCell, we assign the values in cellForRowAtIndexPath as
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
CustomTableViewCell *cell = (CustomTableViewCell *)[tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
[[NSBundle mainBundle] loadNibNamed:#"CustomTableViewCell" owner:self options:nil];
cell = customTableViewCell;
}
cell.label1.text = #"text1";
cell.label2.text = #"text2";
// Configure the cell...
return cell;
}
This way of using CustomCell is a usual one. The texts will be displayed on the labels of the cell, but I need some clarification in using CustomCell in another way. I have a method in MainViewController like the following
- (void)methodInMainViewConroller {
CustomCell *customCell = [[CustomCell alloc] init];
[customCell methodInCustomCell];
[tableView reloadData];
}
and in CustomCell, I have the definition for the method as
- (void)methodInCustomCell {
self.label1.text = #"text1";
self.label2.text = #"text2";
}
Will this work? Will the text be displayed on the labels of the cell? Actually it doesn't work for me. Anyone help me to make this work perfectly. Thanks in advance.
You can try this
- (void)methodInMainViewConroller {
NSIndexPath *indexPath = [NSIndexPath indexPathForRow:row inSection:section];
CustomCell *customCell = (CustomCell *)[self.tableView cellForRowAtIndexPath:indexPath];
[customCell methodInCustomCell];
}
UPDATE: What I've just realized is that once you scroll the table view your labels will be reset to previous values. It might not work this way, but give it a try.
Take a good look at your code. You never actually do anything with that cell once you set the labels. Anyway, how would the tableview know to use your cell and where to put it?
It doesn't work because the cell you alloc/init and work on is a totally different object. You can, however, store that cell as an ivar and always return that very cell for the given indexPath.
This method don't work because you call it for just created custom cell not for cell in tableView.
You need something like this:
CustomCell *customCell = [tableView cellForRowAtIndexPath:indexPath];
[customCell methodInCustomCell];
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 change the textLabel and detailTextLabel of a cell when it has been selected.
I've tried the following, but no change occurs:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
MyAppDelegate *appDelegate = (MyPhoneAppDelegate*)[[UIApplication sharedApplication] delegate];
UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
cell.detailTextLabel.text = #"xxxxx";
cell.textLabel.text = #"zzzzz";
[tableView reloadData];
}
I agree, reloading the table view will actually dump and reload/display all the cells using tableView:cellForRowAtIndexPath: and use the original data, not the updated #"xxxxx" and #"yyyyy" in your tableView:didSelectRowAtIndexPath: method.
In a little test project I was able to change the labels upon selection with:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell * cell = [tableView cellForRowAtIndexPath:indexPath];
cell.textLabel.text = #"it was tapped";
}
You should not be trying to reload the table while a cell is selected. Instead, try
[cell setNeedsLayout]
after you make the above changes to the labels.
Also, is there a reason you're making a reference to the app delegate in the method?
Try to reload the cell you selected (described by indexPath) :
[yourTableView reloadRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationNone];
Create a New iPad Project (Split View) and Now go through the Classes->Files. The easiest way's been given there. The XCode's Generated Codes.
Sample Code Lines :-
cell.textLabel.text = [NSString stringWithFormat:#"Row %d", indexPath.row];
You can use them in cellForRowAtIndexPath ||&& didSelectRowAtIndexPath ..
Not sure what you're trying to do with the delegate but you should try calling the tableView already instantiated; i.e. call
UITableViewCell *cell = [self.tableView cellForRowAtIndexPath: indexPath];
Maybe I'm not clear
What I'm saying is that you are instantiating a new empty table view
UITableViewCell *cell = [**tableView** cellForRowAtIndexPath: indexPath]; //cell has nothing it is new.
consider replacing to call the old
UITableViewCell *cell = [**self.tableView** cellForRowAtIndexPath: indexPath]; //now you have one that has a textField already in it
Did you try to refresh only the selected cell instead of reloading the whole table ?
[cell setNeedsDisplay];
instead of
[tableView reloadData];
This will have better performance and I'm not but I suppose that selection is lost if you refresh the whole table (this may be the reason why you don't see any change in the end)....