Save each didSelectRowAtIndexPath click's object in MutableArray

Question

I have a list of items/cells in TableView. Table is set to allow multiple selection.

So, i have these methods to select and deselect.

@interface NotificationsViewController : UIViewController <UITableViewDataSource, UITableViewDelegate,UIScrollViewDelegate>
{
NSMutableArray *checkedIndexPaths;
}

-(void)viewDidLoad{
//Setup default array
checkedIndexPaths = [[NSMutableArray alloc]init];
}

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{

NotificationsTableViewCell *cell = (NotificationsTableViewCell*)[tableView cellForRowAtIndexPath:indexPath];
cell.imgIcon.image=[UIImage imageNamed:@"select-icon"];

Notifications* selected = notifications[indexPath.section];
selectedGroup = selected.NotificationsId;

[checkedIndexPaths addObject:selectedGroup];

}

-(void)tableView:(UITableView *)tableView didDeselectRowAtIndexPath:(NSIndexPath *)indexPath{

NotificationsTableViewCell *cell = (NotificationsTableViewCell*)[tableView cellForRowAtIndexPath:indexPath];
cell.imgIcon.image=[UIImage imageNamed:@""];

Notifications* selected = notifications[indexPath.section];
selectedGroup = selected.NotificationsId;

[checkedIndexPaths addObject:selectedGroup];

}

I want to add each object into array during multiple selection. But with this current coding, it will overwrite the same one, and i have no idea how can i make it multiple object array to store in each click of cell. Thank you for your helps.

You should use a for/in loop. And before you ask what that is, if you don't know. Try doing some research. Here is a great example provided by Apple : https://developer.apple.com/library/ios/samplecode/TableMultiSelect/Introduction/Intro.html there's a lot going on with your code that isn't fundamentally efficient. Try cross referencing all your methods against apples and learn from how they implicit structure. — soulshined, Jun 29 '15 at 03:52
There's also no reason for this `NotificationsTableViewCell *cell = (NotificationsTableViewCell*)[tableView cellForRowAtIndexPath:indexPath];` you already know the indexPath from the method itself. Plus you don't actually do anything with the cell — soulshined, Jun 29 '15 at 03:54
@soulshined i had need to use cell.imgIcon.image=[UIImage imageNamed:@"select-icon"]; thats why i declared the 'cell'. — Umit Kaya, Jun 29 '15 at 05:21

score 1 · Accepted Answer · answered Jun 29 '15 at 02:51

1

You're creating new NSMutableArrays after each method call. Your listArray should be a property of the object, or otherwise visible outside of the scope of these two methods, that you add and remove items from on each method call.

answered Jun 29 '15 at 02:51

Connor Neville

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Thanks. But the problem is in each call it will overwrite on the same object. what mechanism i can use to store multiple? – Umit Kaya Jun 29 '15 at 03:01
That is not your problem: your line `NSMutableArray *listArray = [[NSMutableArray alloc] init];` creates a new, blank array each time. That is why, when you select, multiple items, it appears the second overwrote the first. – Connor Neville Jun 29 '15 at 03:02
i changed my question, but in this case array can't be called fro viewDidload. it says: 'use of undeclared identifier'. – Umit Kaya Jun 29 '15 at 03:09
Google "Objective C properties". Regardless of where you write it, that line is creating a local variable which will only exist in the scope of the method you are inside. You will need a grasp of this concept to do any sort of iOS programming. – Connor Neville Jun 29 '15 at 03:28

Save each didSelectRowAtIndexPath click's object in MutableArray

1 Answers1