UITableView - insert new row by tapping on existing cell - ios

I use UITableView with prototype cells and would like the top most cell to be an "adder" cell: when user taps on that cell, the segue is being performed. As the UITableView is being dynamically generated (except the top one) and cells are being reused, I have two question:
1 - is it possible to make one static cell while all the others will remain prototype cells?
2 - If not, how to implement this solution? I think, it has to be implemented in
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
but I have no idea, is this method right place to do it. Am I correct, to implement this custom cell, I need to check, whether indexPath.row = 0 and substitute the needed cell with custom, while programmatically shifting all the cells one row down?

Yiu can do on the Tap of Your cell, you can create two different cell, one your prototype cell and one for your details
in your
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
if (indexPath.row == 0) {
AdderCell *cell = (AdderCell*)[tableView dequeueReusableCellWithIdentifier:#"AdderCell" forIndexPath:indexPath];
} else {
CustomCell *cell = (CustomCell*)[tableView dequeueReusableCellWithIdentifier:#"CustomCell" forIndexPath:indexPath];
}
}
on tap of your Adder cell in
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
if (indexPath.row == 0) {
// add data to your row array and reload the tableRow
} else {
// do your tap action
}
}

Related

Change button image on a cell when a tableView Cell is selected

I'm having a UITableView with the table view cell loaded from an .xib.
Which has a label text and a checkmark button.
I want to change the checkmark image of the button when the cell is selected. (Allows multiple selection).
From these selected cells with changed checkmark image, i'm performing an operation.
Can anyone tell me how this could be done?
Thanks in advance....
Follow the below to change the button image.
Single Selection
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
if (selectedIndex == indexPath.row) {
// change image here...
}
}
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
selectedIndex = indexPath.row;
[tableView reloadData];
}
If you need for multiple selection then you can maintain a array to capture the indexes and do the needful like below.
Multiple selection
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
if ([selectedIndexArray containsObject:indexPath.row]) {
// change image to check mark here...
} else {
// Change image to un-check mark
}
}
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
if ([selectedIndexArray containsObject:indexPath.row]) {
[selectedIndexArray removeObject:indexPath.row];
} else {
[selectedIndexArray addObject:indexPath.row];
}
[tableView reloadData];
}
You can have a field isCheckMarked in your model class, which you have then put in array for your tableview to populate. You can then toggle that flag in didSelectRow delegate of tableView and can change checkmark image based on isCheckMarked

Add a cell to the bottom of UITableView that only appears when there is no more content

So I want to add a cell to the bottom of a UITableView that only appears when there is no more content.
The goal is that when there is no more users in the list I want to have a cell that shows up with Twitter, Facebook etc buttons so the user can invite more users. Any hints?
All the best
Start off by creating different NSTableViewCell's - one for your regular data and one for your "Social Media" cell at the end.
In the UITableViewDataSource you can report the number of rows as being one greater than the total number of rows for your data
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
return [mDataSource count] + 1;
}
Then, in your cellForRowAtIndexPath method, check if it's the last row, and return your "social media" cell.
// Customize the appearance of table view cells.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath*)indexPath {
NSString *cellIdentifier = #"Cell";
if (indexPath.row == [mDataSource count] + 1) {
cellIdentifier = #"SocialCell";
}
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
...
}

UITableViewCell hide content when is not visible

I have gif animated pictures in some uitableview rows,
When there is a lot of gifs in tableview CPU usage is going to be very high,
So I want to hide these gifs when their row is not visible,
How can I do that ?
How can I achieve not visible cells row's indexPath ?
After that I can hide the gif like that :
UITableViewCell *celll = [ tableView cellForRowAtIndexPath:indexPath];
UIImageView *gif = (UIImageView*)[celll viewWithTag:30000];
gif.hidden = TRUE;
So I must get not visible cells indexPath's in a loop.
Generally, you don't need to do that as long as you properly use reusable cells.
Nevertheless, if you do want to do that, you can use tableView:didEndDisplayingCell:forRowAtIndexPath: method on UITableViewDelegate:
- (void)tableView:(UITableView *)tableView didEndDisplayingCell:(UITableViewCell *)cell
forRowAtIndexPath:(NSIndexPath *)indexPath {
UIImageView *gif = (UIImageView*)[celll viewWithTag:30000];
gif.hidden = YES;
}
If you'll put the line:
NSLog(#"%#",indexPath);
as the first line of the method:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
You'll realise that it's done automatically. Only the visible cells, i.e the one that appears on the screen, are the one you present the data for.
Sorry for poor english.You had not posted code about how your cellForRowAtIndexPath implementation look like,i will suggest to make your cellForRowAtIndexPath like below.
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{
static NSString *CellIdentifier = #"YOURIDENTIFIERSTRING";
UITableViewCell *cell = [tableView dequeReusableCellWithIdentifier: CellIdentifier forIndexPath:indexPath];
// Configure the cell here …
return cell;
}
This way only those many cells will be created which are visible on device and once row goes out of device view it will be reuse for new row. Please check apple doc for tableview.

Update single section of multi-section UITableView

I have a UITableViewController created in storyboard. It has two sections. The first section's rows contain controls laid-out in storyboard. I want to update the rows in the second section using values in an array.
I'm fairly new to iOS development. I understand how to use a UITableViewDataSource to update a table based on the array, but not how to restrict the updates to a specific section. Can anyone outline how to do this?
EDIT This seemed like a simple problem, so I thought I code would just obscure the question. Maybe I was wrong. Heres what I have:
My numberOfRowsInSection function returns 1 in the section number is 0, because the first section (the one I designed in storyboard) has a single row, otherwise it returns the number of elements in the backing data array:
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
if (section == 0)
return 1;
else
return [myData length];
}
My cellForRowAtIndexPath function creates a cell if the section number is 1. But I don't know what to do if the section number is zero. How do I avoid having to recreate the rows I laid-out in storyboard?
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
if(indexPath.section == 1)
{
cell.textLabel.text = [myData objectAtindex:indexPath.row];
}
else
{
// What to do here?
}
}
Well If you only have few static controls in the first section why won't you put these controls in a table header view instead? Thus you'll only have one section to worry about :)
In your method - (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPathadd this
Create 2 differents UITableViewCells and reference them like this
if (indexPath.section == 1) {
NSString *CellIdentifier = #"DynamicCell";
VideoCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
//You are drawing your second section so you can use your array as values
cell.property1...
cell.property2...
cell.property3...
return cell;
}else{//If you have only 2 sections then else represent your first section
//You are drawing your first section
NSString *CellIdentifier = #"StaticCell";
VideoCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];
return cell;
}
You can change the row value in the delegate method
-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
To identify the section, just use:
indexPath.section
You can use reloadRowsAtIndexPaths: with an array of all the indexPaths that are in the wanted section, built with a loop and a NSMutableArray.
- (void)reloadSections:(NSIndexSet *)sections
withRowAnimation:(UITableViewRowAnimation)animation;
The parameter "section" is An index set identifying the sections to reload.

Custom empty cells in UITabelView

i got ios application with UITableView
I customize cells in this table, but when number of objects lower than visible cells on screen, all other cells look like simple UITableViewCells.
It should look like this
How should i customize all cells?
UPD Code for dataSource:
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 the number of rows in the section.
return [dataBase.showMaps count];
}
-(CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{
return 70;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
ShowMapCell *cell = (ShowMapCell*) [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[ShowMapCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
// Configure the cell...
ShowMap *sM = [dataBase.showMaps objectAtIndex:indexPath.row];
//cell.textLabel.text = sM.name;
[cell initShowMapCell:sM index:indexPath.row];
return cell;
}
You could have just set background color of the tableview. However that solution wont work because you are using different backgrounds for each cell.
So according to me to achieve what you want you need to add some extra (blank) rows to the table and for that you need to return your record + extra cell (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section method. And above that you need to set the background color of table view to one of the cell background because if you are using bouncing effect in the tableview you will find white color when you scroll the tableview up/down.
If you want your UITableView not to have 'empty cells', you will need to hide the cell separators and change the background colour of the tableview to match your colour scheme.
As katzenhut said in the comments, they aren't cells, they are placeholders for content. So if you hide the separators and add them in the xib file for your UITableViewCell ShowCell, then they will no longer be seen when there isn't a cell to place in the table.

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