I have a NSTableView, its data source and delegate have been set. And I want to customize the cell, so I dragged a view-based cell view from the library. Then I created a class ServiceCell which inherits from NSTableCellView in order to fully control my special cell. After that, I control-drag from the nib file to the cell class to create the IBOutlet properties of the image and text field in the cell.
In the NSTableView's delegate methods, I wrote this:
- (NSView *)tableView:(NSTableView *)tableView viewForTableColumn:(NSTableColumn *)tableColumn row:(NSInteger)row {
// Get a new ViewCell
ServiceCell *cellView = [tableView makeViewWithIdentifier:#"ServiceCell" owner:self];
NSLog(#"Field = %#", cellView.textField); //which turns out to be null!!!
if( [tableColumn.identifier isEqualToString:#"ServiceColumn"] )
{
cellView.serviceImage.image = nil;
cellView.nameLabel.stringValue = #"Hello";
return cellView;
}
return cellView;
}
As you can see, the text field is null! But makeViewWithIdentifier: has found the cell in Interface Builder and displayed the cell in the app window. I just cannot set it's value, Why?
The problem is you are accessing your textfield but not accessing its textvalue. Try your log statement like this below:-
NSLog(#"Field = %#", cellView.textField.stringValue);
in Table view select cell and give identifier name (same as you are using in code, for your snipped it will be #"ServiceCell"), your code part is right it will work.
Related
Hello I'm trying to use an NSTableView in my program and I'm having a problem setting the values for the NSTableCellView and getting them to display in the NSTableView. When I run my program, only blank cells show up. Using NSLog's, I can see that the cell imageView gets set, but doesn't display. When I go to set stringValues for the NSTableCellViews however, I only get null from my NSLog's despite the string containing data. Here's the delegate method I'm having a problem with:
-(NSView *)tableView:(NSTableView *)tableView viewForTableColumn:(NSTableColumn *)tableColumn row:(NSInteger)row {
NSString *cellIdentifier;
NSImageView *pageImageView;
NSString *pageString;
int pageVotes;
if (_connectionArray.count == 0) {
return nil;
}
NSTableCellView *cellView = [[NSTableCellView alloc] init];
if (tableColumn == tableView.tableColumns[0]) {
cellIdentifier = #"firstColumn";
pageImageView = [[_connectionArray objectAtIndex:row] getImage]; //Gets imageView from Page Object
cellView.imageView = pageImageView; //Set image view for cell
NSLog(#"%#", cellView.imageView); //This works
}
if (tableColumn == tableView.tableColumns[1]) {
cellIdentifier = #"secondColumn";
pageString = [[_connectionArray objectAtIndex:row] getTitle];
cellView.textField.stringValue = pageString; //Set text for cell
NSLog(#"%#", cellView.textField.stringValue); //Does not work, returns null
}
if (tableColumn == tableView.tableColumns[2]) {
cellIdentifier = #"thirdColumn";
pageVotes = [[_connectionArray objectAtIndex:row] getVotes];
pageString = [NSString stringWithFormat:#"%i", pageVotes]; //Convert int to string
cellView.textField.stringValue = pageString; //Set text for cell.
NSLog(#"%#", cellView.textField.stringValue); //Does not work, returns null
}
[_tableView makeViewWithIdentifier:cellIdentifier owner:self];
return cellView;
}
I think everything set-up correctly between the Storyboard and the ViewController as well, but I could very well be wrong since this is my first time working with NSTableViews. I've also tried using:
[cellView setImage:pageImageView];
[cellView setTextField:[NSTextField textFieldWithString:pageString]];
but I run into the same issue. If anyone can help I greatly appreciate it! I feel like I'm missing something simple...
Setting the textField and imageView properties of NSTableCellView does not add a text field or an image view to the cell view. Those outlets are just intended to inform the cell view about which of its subviews are the primary text field and/or primary image view. You are still responsible for adding those views to the cell view as subviews or, possibly, as deeper descendant views.
Also, it's a bad idea for your model to vend views. That's not how it should work. Among other things, that will specifically interfere with adding those views to the cell view's subview hierarchy.
It's also strange that you're both creating the cell view and asking the table view to make it (by calling -makeViewWithIdentifier:owner:). Normally, you'd do one or the other, or first try -makeViewWithIdentifier:owner: and only create a view if that fails. And, of course, you wouldn't ignore the return value.
Frankly, the best thing to do is set this all up in Interface Builder. If you do it right, there's no need to implement -tableView:viewForTableColumn:row: at all. Is there a reason you didn't go that route?
I created a custom NSView for a NSTableView.
I am trying to fill the fields I created in it using the Interface Builder but I can't. I would say each component is properly linked and the code is OK.
This is the function
- (NSView *)tableView:(NSTableView *)tableView viewForTableColumn:(NSTableColumn *)tableColumn row:(NSInteger)row
{
Account *account = (Account *)[self.dataSource objectAtIndex:row];
AccountTableCellViewController *controller = [[AccountTableCellViewController alloc] init];
controller.subtitleLabel.stringValue = account.name;
[controller.titleLabel setStringValue:account.num];
NSLog(#"%#", controller.titleLabel);
return [controller view];
}
And here is the picture of the bindings:
The table shows all the rows correctly, but is not filling the NSTextFields as expected.
UPDATE:
This is how it looks like (not updating views):
Any suggestion?
The labels haven't been loaded from the nib yet. I'd just create an extra account instance variable in your view controller, assign it there, then load the information in -(void)awakeFromNib
First i changed my NSTableView to view based and created an
IBOutlet of my NSTableView.
Then i dragged the Image & Text Table Cell View to it.
After that i changed the NSImageView that's inside that cell view
to my custom NSImageView subclass: 'PVAsyncImageView'.
I imported it on my .h.
And i have this code:
- (NSView *)tableView:(NSTableView *)tableView viewForTableColumn:(NSTableColumn *)tableColumn row:(NSInteger)row {
NSTableCellView *result = [tableView makeViewWithIdentifier:tableColumn.identifier owner:self];
[[result imageView] downloadImageFromURL:#"lol"];
return result;
}
But it's not recognizing downloadImageFromURL (a method from my NSImageView subclass). Xcode gives me an error.
Any thoughts?
Either your subclass isn't really overriding -init:, or you aren't properly loading your subclass..
Be sure there's no typo in the method name on the subclass: if you have, for instance, -init: in the subclass, the superclass's -init: will still be called.
Are you overriding -allocWithZone: or something somehow?
So I've been given an assignment in my Mobile apps class: make a color game app for the iphone.(The description of how to game works is at the top of the pasted viewcontroller.h file below.)
I'm very new to Objective-C and cocoa, but have managed to troubleshoot and fix a lot of things in this app. The problem I have right now is that I don't know how to properly initialize and send UITableViewCells to the view. I'm confused because all of the tutorials I've found online use datasource methods to change different attributes of the UITableView and the cells as well. I'm not sure how these methods will interact with the controls I've already placed. I'm confused because I added them by the storyboard file, not by defining tableview attributes with datasource code.
My immediate issue is that my program won't display the proper text to the cells textlabel and detailtextlabel.
I've looked everywhere online for UITableView and UITableViewCell tutorials, but they are all from years ago and I'm not sure if the advent of the storyboard has changed the way I would treat these controls.
All of the code I've written is either in the viewcontroller.m or viewcontroller.h files.
The method within ViewController.m file, that should call the cell and display text and detail text:
-(IBAction)enterClicked
{
//On enter- send instance colors to the colorTable row[i], perform comparisons and append the resulting symbols to the instanceResults String. Send instanceResults string to the resultTable row[i]. When game counter reaches 6, gameOver. If on comparisons check, the instanceColors are the same as the gameColors, then the player wins.
[self checkForLoss];
if(!self.gameOver)
{
resultOfGuess = [self comparePlayerInputToGameColors:guessColors];
[listOfGuesses addObject:guessColors];
[listOfOutcomes addObject:resultOfGuess];
NSIndexPath *indexPath = [NSIndexPath indexPathForRow:_numberOfTurnsPlayed inSection:0];
UITableViewCell *thisCell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:CellIdentifier];
thisCell.textLabel.text = [self.listOfGuesses lastObject];
thisCell.detailTextLabel.text = [self.listOfOutcomes lastObject];
[guessColors setString:#""];
if([self checkForWin:resultOfGuess])
[UpdateLabel setText:#"You have won!"];
else
[UpdateLabel setText:#""];
self.colorCounter = 0;
self.isStepOne = YES;
_numberOfTurnsPlayed++;
}
else
{
if([self checkForLoss])
[UpdateLabel setText:#"You have lost!"];
}
}
The UITableView DataSource Methods I've called at the bottom of the viewcontroller.m file:
#pragma mark - UITableViewDataSource protocol
- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section
{
if(section == 0)
return #"Guesses: Results:";
return 0;
}
-(NSInteger) numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
-(NSInteger) tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return 6;
}
-(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];
}
return cell;
}
So my questions are: Can I change a control's properties with datasource methods, if I created the controls through the storyboard? How do I properly display the text in a uitableview's cells?
Edit/update: Thank you, I've used your advice jrturton, but now I've found something peculiar that may be the source of my problems. in my viewController.h file I've changed my header from
ViewController: UIViewController to ViewController: UITableViewController
Thinking that the datasource methods I call within the viewcontroller files have to be able to call the same methods and properties of the class that I call in the header-- Also, I see this done in other UITableView tutorial files.
The problem is that when I change the header to read-- ViewController: UITableViewController -- and I try to compile, I get this error:
Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: '-[UITableViewController loadView] loaded the "2-view-3" nib but didn't get a UITableView.'
It compiles fine if I use just :UIViewController in the header file though.
Any ideas?
Further update: I''ve noticed within my storyboard that the only available ViewController object is a UIViewController object, while in the other tutorial files I've seen, this ViewController object is a UITableViewController object. I imagine this is my problem, but I can't seem to switch my UIViewController object to a UITableViewController. All I can do is create a new one, which isn't what I want, I imagine.
Your action method should update the data model (which I think it does, since it changes your listOfGuesses array). You then need to let your table view know that you have added or updated rows so that it can re-load them for you - check the UITableView documentation for reloading data or specific rows.
Creating a cell outside of the datasource methods isn't going to let that cell appear in your table.
At the moment I'm guessing you have 6 empty cells in your table view? You need to populate the text and detail labels in your cellForRowAtIndexPath method. The difference now there are storyboards is that you don't need to do the if (cell == nil) bit, as long as you have set the re-use identifier in your storyboard prototype cell then it will do all that for you. So your cellForRowAtIndexPath method can be reduced to:
-(UITableViewCell *) tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath*)indexPath
{
// This will dequeue or create a new cell based on the prototype in your storyboard
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:#"Cell"];
// Put your actual configuration here based on your model array
cell.textLabel.text = #"Hello";
return cell;
}
Further hints (this is homework so I'm not giving full samples)
'indexPath.row` in the above method will give you the index from your model array that the cell refers to
You have defined the table as having 6 rows, but you are adding items to your model arrays as you go - so when the table asks for row 5, and your model only has 3 entries, you need to deal with this. Consider changing the number of rows in the table dynamically and using table view methods to indicate that new rows have been added. Again, see the UITableView documentation for this.
Typically the text is set in each cell by accessing the setText property:
[[cell textLabel] setText:#"static string"];
or
[[cell textLabel] setText:someNSString];
or with .dot notation
cell.textLabel.text = someNSString;
return cell;
BTW this is done in the method:
-(UITableViewCell *) tableView:(UITableView *)tableView cellForRowAtIndexPath:
I have a flawless functioning view-based NSOutlineView with a proper set-up datasource in my project. Now I want to allow the user to change certain entries. So I made the NSTextField in the IB editable. For a cell-based NSOutlineView you can use the delegate method outlineView:setObjectValue:forTableColumn:byItem: however it's not available for a view-based NSOutlineView as stated in the header file for the NSOutlineViewData protocol:
/* View Based OutlineView: This method is not applicable.
*/
(void)outlineView:(NSOutlineView *)outlineView setObjectValue:(id)object forTableColumn:(NSTableColumn *)tableColumn byItem:(id)item;
So I searched for another delegate method and found outlineView:shouldEditTableColumn:item:. However this delegate method doesn't get fired. Probably because I'm not editing a cell.
So my question is: Is there any other way to notice when a row changed than having a delegate for each NSTextField?
You are correct that your text field needs to be editable in Interface Builder.
Next, make your controller conform to NSTextFieldDelegate. Then, set the delegate for the text field in outlineView:viewForTableColumn:item:, like so:
tableCellView.textField.delegate = self
Here's a simplified example, where you've implemented the method for returning the table cell view for an item for your outline view.
-(NSView *)outlineView:(NSOutlineView *)outlineView viewForTableColumn:(NSTableColumn *)tableColumn item:(id)item
{
NSTableCellView *tableCellView = [outlineView makeViewWithIdentifier:#"myTableCellView" owner:self];
MyItem *myItem = (MyItem *)item; // MyItem is just a pretend custom model object
tableCellView.delegate = self;
tableCellView.textField.stringValue = [myItem title];
tableCellView.textField.delegate = self;
return result;
}
Then, the controller should get a controlTextDidEndEditing notification:
- (void)controlTextDidEndEditing:(NSNotification *)obj
{
NSTextField *textField = [obj object];
NSString *newTitle = [textField stringValue];
NSUInteger row = [self.sidebarOutlineView rowForView:textField];
MyItem *myItem = [self.sidebarOutlineView itemAtRow:row];
myItem.name = newTitle;
}
Well, it seems like Apple wants us to use the delegate methods of each NSTextField as stated here:
This method is intended for use with cell-based table views, it must not be used with view-based table views. Instead target/action is used for each item in the view cell.
So there's currently no other way to do this.