im learning Obj-C and im treating to make my first UITableView with "Hello world" text.
My problem is i can't show on screen right edit button. this is my code:
- (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];
}
[[cell textLabel] setTextAlignment:(UITextAlignmentCenter)];
cell.textLabel.text=#"Hello World";
//[cell.textLabel setText:#"Hola2"];
return cell;
}
and:
- (void)viewDidUnload
{
[super viewDidUnload];
self.navigationItem.rightBarButtonItem=self.editButtonItem;
}
Am I missing something?
Thanks for help.
self.navigationItem.rightBarButtonItem=self.editButtonItem;
This must go in the viewDidLoad
are you also setting the rows and sections correct?
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
// Return the number of sections.
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
// Return the number of rows in the section.
return 1;
}
Related
i have 2 views-view1 and view2, one for entering data and another for displaying the entered data.
I am able to display the entered data in view2 in labels. But how to display the data in a UITableView. Following is my code to display the data:
view2.m
#synthesize details; //details is an object of NSMutableArray.
- (void)viewWillAppear:(BOOL)animated {
[super viewWillAppear:animated];
textLabel.text = self.name;
lblCity.text = self.city;
lblGender.text = self.gender;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return [details count];
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *simpleTableIdentifier = #"SimpleTableItem";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:simpleTableIdentifier];
if (cell == nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:simpleTableIdentifier];
}
cell.textLabel.text = [details objectAtIndex:indexPath.row];
//cell.imageView.image = [UIImage imageNamed:#"creme_brelee.jpg"];
return cell;
i debuuged and found that cellForRowAtIndexPath is never called.
Where am i getting wrong? How do i solve it?
You need to create a NSMutableArray of display Data in to UITableViewCell like below and don't forget to declare UITableView delegates in .h file <UITableViewDataSource,UITableViewDelegate> and also connect your UITableView IBOutlet in your xib and also connect the delegate:
- (void)viewDidLoad
{
[super viewDidLoad];
arrCategorisation=[[NSMutableArray alloc] initWithObjects:#"DataOne",#"DataTwo",#"DataThree", #"DataFour",#"DataFive",nil];
}
#pragma mark - Table view data source
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
// Return the number of sections.
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return arrCategorisation.count;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
NSString *CellIdentifier =[NSString stringWithFormat:#"%d",indexPath.row];
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
cell.textLabel.text=[arrCategorisation objectAtIndex:indexPath.row];
}
// Configure the cell...
return cell;
}
#pragma mark - Table view delegate
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
}
your Table load data like:-
In my app, You can tap a cell, and it brings up a new view. You can edit the tableviewCell's textLabel, and save it. But when you switch views and come back to the tableView, the cells are in a different order. What could be the reason for this?
Here is my Code:
-(UITableViewCell *) tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
static NSString * identifier = #"identifier";
self.cell = [tableView dequeueReusableCellWithIdentifier:identifier];
h = [self.tableArray objectAtIndex:indexPath.row];
NSString *brandModel = [[h.brand stringByAppendingString:#" "] stringByAppendingString:h.model];
self.cell.mainLabel.text = brandModel;
self.cell.nicknameLabel.text = handguns.nickname;
return self.cell;
}
If you are reloading tableView after saving UITableView cell then It will be reordered as initial because array from which you are setting cell data is as it is.You can change only table View cells not array data position in an array.
Below I have written a UITableView code to move cells and it is working fine after pushing view.If I remove reload method from viewWillAppear:
#import "MoveCellViewController.h"
#interface MoveCellViewController ()
#end
#implementation MoveCellViewController
- (void)viewDidLoad
{
UIBarButtonItem *left=[[UIBarButtonItem alloc] initWithTitle:#"Edit" style:UIBarButtonItemStyleBordered target:self action:#selector(edit)];
self.navigationItem.leftBarButtonItem=left;
myArray=[[NSMutableArray alloc]init]; //mutable array;
myArray=[NSMutableArray arrayWithObjects:#"Aman",#"Ankit",#"Sumit",#"Hercules",#"Jackie Chan", nil];
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
-(void)edit
{
if (self.navigationItem.leftBarButtonItem.title==#"Edit") {
self.navigationItem.leftBarButtonItem.title=#"Done";
[_tableView setEditing:YES];
}else
{
[_tableView setEditing:NO];
self.navigationItem.leftBarButtonItem.title=#"Edit";
}
}
- (void)didReceiveMemoryWarning
{
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return [myArray count];
}
// Row display. Implementers should *always* try to reuse cells by setting each cell's reuseIdentifier and querying for available reusable cells with dequeueReusableCellWithIdentifier:
// Cell gets various attributes set automatically based on table (separators) and data source (accessory views, editing controls)
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *cellIdentifier=#"cellIdentifier";
UITableViewCell *cell=[tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell==nil) {
cell=[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier];
}
cell.userInteractionEnabled=YES;
cell.textLabel.text=[myArray objectAtIndex:indexPath.row];
return cell;
}
- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath
{
return YES;
}
- (UITableViewCellEditingStyle)tableView:(UITableView *)tableView editingStyleForRowAtIndexPath:(NSIndexPath *)indexPath{
return UITableViewCellEditingStyleNone;
}
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)sourceIndexPath toIndexPath:(NSIndexPath *)destinationIndexPath{
id ob = [myArray objectAtIndex:destinationIndexPath.row];
[myArray replaceObjectAtIndex:destinationIndexPath.row withObject:[myArray objectAtIndex:sourceIndexPath.row]];
[myArray replaceObjectAtIndex:sourceIndexPath.row withObject:ob];
}
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
NextViewController *nx=[[NextViewController alloc] init];
[self.navigationController pushViewController:nx animated:YES];
}
#end
This is working code and will not change after push view controller.
-(UITableViewCell *) tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
NSString *CellIdentifier = [NSString stringWithFormat:#"S%1dR%1d",indexPath.section,indexPath.row];
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil)
{
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:CellIdentifier];
cell.selectionStyle = UITableViewCellSelectionStyleNone;
}
h = [self.tableArray objectAtIndex:indexPath.row];
NSString *brandModel = [[h.brand stringByAppendingString:#" "] stringByAppendingString:h.model];
self.cell.mainLabel.text = brandModel;
self.cell.nicknameLabel.text = handguns.nickname;
return self.cell;
}
-(UITableViewCell *) tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
static NSString *CellIdentifier = #"Cell";
cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil)
{
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleValue2 reuseIdentifier:nil];
}
Write rest of the code here
}
I have a simple UITableView with 9 cells. When I move the table up or down by scrolling, I get EXE bad access. NSZombieMode points at the cellForRowAtIndexMethod.
- (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];
}
cell.textLabel.text = [lineArray objectAtIndex:indexPath.row];
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
return cell;
}
Can anyone suggest what is wrong ?
If ARC is disabled then add autorelease when you create cell
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:CellIdentifier] autorelease];
This can be the reason of the leaks. Check also lineArray since it used like ivar and probably this array was released at some point.
My guess is you're trying to access an element in your lineArray that is out of bounds.
IE: indexPath.row is returning a 6 when you only have 3 elements in your lineArray.
It's occurring when you scroll down as it triggers cellForRowAtIndexPath to be called on higher number rows (rows that with indexPath.row > 3 for example)
I'll go one more step and guess that you're probably statically returning numberOfRowsForSection.
Setting it to lineArray.count should fix it.
According to my understanding :-
1) in the lineArray you have some 9 items but in the numberOfRowsInSection you are returning the rowCount more than the items in the array and so it crashes and points to ceelForRowAtIndex.
2) Here is the sample code for your understanding :-
- (void)viewDidLoad
{
[super viewDidLoad];
lineArray = [[NSMutableArray alloc]initWithObjects:#"1",#"2",#"3",#"4",#"5", nil];
tableView1 = [[UITableView alloc]init];
tableView1.delegate = self;
tableView1.dataSource = self;
tableView1 .frame =self.view.frame;
[self.view addSubview:tableView1];
}
- (void)viewDidUnload
{
[super viewDidUnload];
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation
{
return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return [lineArray count];
//return ;
}
- (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];
}
cell.textLabel.text = [lineArray objectAtIndex:indexPath.row];
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
return cell;
}
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
}
I have a button that when pressed, a tableview section will be added and will also add a new row to that section. How can I implement this programatically?
I have an array of cells.
Here are my codes
- (IBAction)addCell:(id)sender {
UITableViewCell *newCell = [[UITableViewCell alloc] init];
counter++;
[cells addObject:newCell];
[self.tableView reloadData];
}
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return [cells count];
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return 1;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
//this is where i want to adjust the row per section
//this code hide the recent sections, only the current created section appears
return [cells objectAtIndex:indexPath.row];
}
Hi try reading this:
How to display the UITableView programmatically?
Adding cells programmatically to UITableView
Hope this could help you.
First, update your's datamodel(NSArray or mutable). Second, when you want tableview refresh, add a code [self.tableView reloadData];
oops, your code some strange uitaleviewDataSource, Delegate Method.
also, your have a some mistake.
why you implements numberOfRowsInSection return 1? very strange.
I apprecated below code.
CASE 1. No has DataModel.
- (IBAction)addCell:(id)sender
{
cellRowsCount++;
[self.tableView reloadData];
}
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return 1;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return cellRowsCount;
}
- (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];
}
return cell;
}
your codes, dataModel(NSArray or mutable) does not necessarily need, so I simply rowCount variable added and your rowsCount of tableviewCell has synchronized.
If you wanna with DataModel, below CASE2. refer plz.
CASE2. has DataModel.
- (IBAction)addCell:(id)sender
{
textCount ++;
NSString *cellText = [NSString stringWithFormat:"blah %d", textCount];
[myArray addObject:cellText];
[self.tableView reloadData];
}
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
return [myArray count];
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return [[myArray objectAtIndex:section] count];
}
- (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];
}
cell.textLabel.text = (NSString *)[myArray objectAtIndex:indexPath.row];
return cell;
}
You only have to add the new section and the new item to the array that holds the section and the items like so:
- (void)viewDidLoad
{
[super viewDidLoad];
animals = #{#"Section 1" : #[#"Item 1", #"Item 2", #"Item 3"],
#"Section 2" : #[#"Item 1", #"Item 2"]};
}
after that you just reload the tableView wherever your logic needs:
[self.tableView reloadData];
i have a problem while loading a UITableView on UITabBarController, i got this error while loading table using tab
Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'UITableView dataSource must return a cell from tableView:cellForRowAtIndexPath:'
my code is here
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
// Return the number of sections.
return 2;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
// Return the number of rows in the section.
return 2;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
// Configure the cell...
return cell;
}
i tried many, it may be simple.. anyone please help me?
//Editing in your code, it should work.
- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
// Return the number of sections.
return 2;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
// Return the number of rows in the section.
return 2;
}
- (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];
}
return cell;
}
The problems is that you are using dequeueReusableCellWithIdentifier but you have no code to handle if this returns nil (i.e. when no cells have yet been created to be re-used).
For example:
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil)
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];