I want to set the text of a custom cell that inherits from UITableViewCell with my own method, here's my code:
- (void)updateCell {
NSIndexPath* indexPath;
indexPath= [NSIndexPath indexPathForRow:0 inSection:1];
Somecell *cell = (Somecell *)[mytblview cellForRowAtIndexPath:indexPath];
cell.b_freq.text = #"12332123";
[mytblview reloadData];
}
This code is not updating my UITableView as well. Are there any mistakes in my code or do you suggest using a different method?
You need to implement the UITableViewDataSource delegate method yourself rather than calling it and then modifying the cell that is returned:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
if (indexPath.section == 1 && indexPath.row == 0) {
Somecell *cell = [[Somecell alloc] init];
cell.b_freq.text = #"12332123";
return cell;
}
}
Implement the method and then return the cell that you want.
Check out the Apple documentation for more info.
Related
In a VC I have 2 tableViews - 1 main and other is added in a drop down menu. From drop down menu TableView "ddTableView", I have added 5 cells in Storyboard itself as prototype cells. Each cell contains an image and a Label. Have also set identifier for each cell. Have also set Accessory Type as "Disclosure Indicator" for each cell of ddTableView.
DataSource and Delegate for mainTV is set to the VC and delegate for ddTableView is set the VC. As the rows are added within the storyboard, I didn't set any datasource for ddTableView in my VC. I managed my delegate methods like this :-
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
if (tableView == ddTableView) {
// RETURNS NIL ???
UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
NSLog(#"CELL Identifier = %#", cell.reuseIdentifier);
return cell;
} else {
}
}
-(void )tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
if (tableView == ddTableView) {
UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
NSLog (#" CELL Clicked of - %#", cell.reuseIdentifier);
}
}
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
if (tableView == ddTableView)
return 44;
else
return 60;
}
-(NSInteger) tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
if (tableView == ddTableView)
return 5;
else
return [chatMsgsArr count];
}
It does call respective delegate method. For cellForRowAtIndexPath it returns cell as nil. Why so ? And on execution, I don't see any contents of the table view - table is blank. I changed the bg color of image and text color also, but yet nothing is seen on execution.
Why so ? Where I may be going wrong ?
You have to allocate the cell, the first time cellForRowAtIndexPath is called. If the cell is not allocated it would return nil as you are getting right now.
What you need to do is allocate the cell only once, the first time you enter cellForRowAtIndexPath. After that you can reuse it as you have done.
If you are planning to use the default tableViewCell your method should look as follows:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
NSString *cellIdentifier = #"your_cell_identifier_name";
if (cell == nil)
{
UITableViewCell *cell = [UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
}
else
{
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier forIndexPath:indexPath];
}
//write the code to populate your cell with data here
//return the cell object
return cell;
}
Hope this helps! :)
- (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] ;
}
if (tableView == ddTableView) {
NSLog(#"CELL Identifier = %d", indexpath.row);
} else {
NSLog(#"CELL Identifier = %#", [chatMsgsArr objectAtIndex:indexPath.row]);
}
return cell;
}
I have a UITableView that display a program name and the DJ name. For some programmes, there are no any DJs. So I created a custom UITableViewCell by putting 2 UILabels. Middle of the UITableViewCell displays the programme name and bottom UILabel displays the DJ name. To display both programme and the DJ name I have to set the cell size and UITableViewCell size as 147. But when DJ is not available I want to hide that bottom label and resize the cell and row height to 70. so how should I do this ?
I am checking if this DJ is null or not inside my cellForRowAtIndexPath method.
How I can resize the cell, and row height ?
Thanks for the help.
You need to use the following delegate:
-(CGFloat)tableView:(UITableView*)tableView heightForRowAtIndexPath:(NSIndexPath*) indexPath {
if(...){
return 147.0f; //or whatever
}
else{
return 70.f;
}
}
Add NSIndexPath below #implementation
NSIndexPath *selectedCellIndexPath;
Add Both of these methods.
// And in the implementation file:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
selectedCellIndexPath = indexPath;
// Forces the table view to call heightForRowAtIndexPath
[tableView reloadRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:UITableViewRowAnimationNone];
}
- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
// Note: Some operations like calling [tableView cellForRowAtIndexPath:indexPath]
// will call heightForRow and thus create a stack overflow
if(selectedCellIndexPath != nil
&& [selectedCellIndexPath compare:indexPath] == NSOrderedSame)
return 338;
return 64;
}
You have 2 types of cell. With height of 147 and 70 pixels.
1) As Anoop Vaidya said you should set cell height by checking "DJ is null or not".
2) To avoid reusing wrong cell template, you should use 2 types of cellIdentifier:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
NSString *CellIdentifier = nil;
if (check DJ is nil or not) {
CellIdentifier = #"CellWithHeight_147";
} else {
CellIdentifier = #"CellWithHeight_70";
}
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:CellIdentifier];
}
...
return cell;
}
I have one UIViewController with UITableView inside,above table I have UISegmentControl, when I press on segment control I want to load a UItableCustomeCell, would you please help me in this implementation, I don't know how should I add them in cellForRowAtIndexPath, Since I have 3 different Custom cell
Here is the code
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath
*)indexPath
{
if (indexPath.row == self.segmentedControl.selectedSegmentIndex == Test1) {
MytestsCell *cell = [tableView dequeueReusableCellWithIdentifier:#"MytestsCell"];
if (!cell) {
cell = [[MyBooksCell alloc] initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:#"MytestsCell"];
}
return cell;
}
else if (indexPath.row == self.segmentedControl.selectedSegmentIndex == tests) {
testCell *cell = [tableView dequeueReusableCellWithIdentifier:#"testCell"];
if (!cell) {
cell = [[TestsCell alloc] initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:#"testsCell"];
}
return cell;
}
break;
case 1:
if (indexPath.row == self.segmentedControl.selectedSegmentIndex == PTest) {
PTestsCell *cell = [tableView dequeueReusableCellWithIdentifier:#"PTestsCell"];
if (!cell) {
cell = [[PTestsCell alloc] initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:#"PTestsCell"];
}
return cell;
}
break;
}
I don't want to have 3 of them in one table, each custom cell is for one segment control
Thanks in advance!
One alternative I can think of is to switch the table views data source. But I would not recommend that. You could define a delegate of your data source and ask it for the table view cell for a selected segmented control. But this just moves the problem. I would stick to your approach.
So...here is what I would do. Starting with iOS6, you no longer need to check if your cell is nil after dequeuing from the tableview if you use
- (id)dequeueReusableCellWithIdentifier:(NSString *)identifier forIndexPath:(NSIndexPath *)indexPath
You are guaranteed to get a cell back as long as the identifier exists. Also, it doesn't look like you need to do any additional configuration so something like this should work:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
NSString *identifier = [NSString stringWithFormat:#"%d", self.segmentedControl.selectedSegmentIndex];
return [tableView dequeueReusableCellWithIdentifier:identifier forIndexPath:indexPath];
}
Edit: I forgot to add, that in order to use this, use numbers that correspond to the segments as the identifier for each cell.
I have a UITableView with one section. All of the cells in that one section have cells that are derived from a subclass of UITableViewCell called PLContactCell.
What I'd like to do is, for the very last row of the table only, not use a PLContactCell. I just want to use a normal UITableViewCell that I can format however I would like. I'd also like to be able to have this cell NOT respond to being tapped.
My initial cellForRowAtIndexPath method is:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
PLContactCell *cell = [tableView dequeueReusableCellWithIdentifier:[PLContactCell reuseIdentifier]];
if (!cell) {
cell = [PLContactCell reusableCell];
cell.delegate = self;
}
id modelObject = [[sections objectAtIndex:indexPath.section] objectAtIndex:indexPath.row];
if ([modelObject isKindOfClass:[NSString class]]) {
[cell configureWithString:modelObject];
} else {
[cell configureWithUser:modelObject];
}
return cell;
}
EDIT
So I tried created a UITableView cell in the XIB file and added the reuse identifier of "newCell" to it. Then I added this code:
if (indexPath.row == [[sections objectAtIndex:indexPath.section] count] - 1) {
NSString *CellIdentifier = #"newCell";
noFormatCell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
}
This doesn't do anything. My question is, how do I access the last row of the section and how do I make it so that that cell it is not a PLContactCell but a UITableView Cell.
If it's always at the end, you might consider using the footer view of the UITableView. You can then keep some extra logic out of your UITableViewDataSource.
If it HAS to be as a cell, you'd have to add an extra row count on your last section, then do an if statement check to watch out for it in your -tableView:cellForRowAtIndexPath: implementation. I would strongly urge you try the footer approach, as it's cleaner and way easier to figure out what you were doing a few months/years from now.
Here's some code. Note you'd need to make another section if you are using grouped style in the UITableView.
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
if (section == sections.count - 1) //Looking for last section
{
return [sections objectAtIndex:section].count + 1; //Add one to the last section
}
return [sections objectAtIndex:section].count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
NSInteger row = indexPath.row;
if ((sections.count == indexPath.section) && [sections objectAtIndex:indexPath.section].count == indexPath.row)
{
//Here you would create and return your UITableViewCell
}
PLContactCell *cell = [tableView dequeueReusableCellWithIdentifier:[PLContactCell reuseIdentifier]];
if (!cell) {
cell = [PLContactCell reusableCell];
cell.delegate = self;
}
id modelObject = [[sections objectAtIndex:indexPath.section] objectAtIndex:indexPath.row];
if ([modelObject isKindOfClass:[NSString class]]) {
[cell configureWithString:modelObject];
} else {
[cell configureWithUser:modelObject];
}
return cell;
}
So I'm trying to store a cell's indexpath when my custom cell is created in
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
I define a custom cell in class called "custom cell", and I added a property to that class defined as such:
#property (nonatomic, strong) NSIndexPath *indexPath;
in cellForRowAtIndexPath I set the index path with customCell.indexPath = indexPath.
When I NSLog it on the very next line it returns null. Could somebody please explain why this is happening?
Edit
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"EditableCell";
EditableCell *editableCell = (EditableCell *)[tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (editableCell == nil) {
editableCell = [[EditableCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
_myTextField = [editableCell textFieldCell];
if (indexPath.section == 0){
[_myTextField setPlaceholder:#"text"];
[_myTextField setReturnKeyType:UIReturnKeyNext];
}
else if (indexPath.section == 1){
[_myTextField setPlaceholder:#"text"];
[_myTextField setReturnKeyType:UIReturnKeyNext];
}
else {
[_myTextField setPlaceholder:#"text"];
[_myTextField setReturnKeyType:UIReturnKeyDone];
}
_myTextField.keyboardType = UIKeyboardTypeDefault;
_myTextField.delegate = self;
return editableCell;
}
Where I call [self.tableview indexpathforcell:cell]
-(BOOL)textFieldShouldReturn:(UITextField *)textField{
if (textField.returnKeyType == UIReturnKeyNext) {
UITableViewCell* myCell = (UITableViewCell*)textField.superview;
EditableCell *currentCell = (EditableCell *)myCell;
NSLog(#"INDEXPATH OF CURRENT CELL: %#",[self.tableView indexPathForCell:currentCell]);
}
}
You can determine the indexPath of a given cell using
-[UITableView indexPathForCell:]
If the cell needs to know it's own indexPath:
NSIndexPath * myIndexPath = [(UITableView *)self.superview indexPathForCell:self]
But if it does, something's not right!
Looking at your edited post I see the problem. You need:
UITableViewCell* myCell = (UITableViewCell*)textField.superview.superview
The textField is actually a subview of the cell's contentView. This always seems a bit wrong to me, so another way to handle this is to make your custom cell the UITextFieldDelegate, and then create a delegate protocol for your cell. So within the cell you'd have:
(BOOL)textFieldShouldReturn:(UITextField *)textField {
if (textField.returnKeyType == UIReturnKeyNext) {
[self.delegate customCell: self textFieldDidReturn: textField];
}
return NO;
}
Then in your cell's delegate you'll have a reference to the cell and textField