Change image from custoum cell - ios

Question

I have a custoum cell with an image , and i want to change the image only when cell is selected.
This i was trying :
- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath {
if (!tableView.tag==0) {
TableViewCell2 *cell = [tableView dequeueReusableCellWithIdentifier:#"cell"];
if (!cell) {
cell=[[TableViewCell2 alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:#"cell"];
}
// cell.cam.image = [UIImage imageNamed:#"cam_normal.png"];
cell.cam.highlightedImage = [UIImage imageNamed:#"cam_selected.png"];
}
}
but the image is not changing.
This is working for a normal cell.
Another try was this in cellForRowAtIndexPath
if (cell.selected==TRUE) {
cell.cam.image=[UIImage imageNamed:#"cam_selected.png"];
}

Answer 1

You already get the cell as a parameter but fetch another one when using dequeueReusableCellWithIdentifier!
Try something like this:
- (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath
{
if (!tableView.tag==0)
{
TableViewCell2 *changeImageCell = (TableViewCell2*) cell;
changeImageCell.cam.highlightedImage = [UIImage imageNamed:#"cam_selected.png"];
}
}

Answer 2

You have to do 2 things:
1. Change the image immediately when the cell is selected.
To do this you must first implement UITableViewCell delegate. But since you already have tableViewWillDisplayCel:forRowAtIndexPath:, I assume that you already have the delegate implemented.
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
TableViewCell2 *cell = [tableView cellForRowAtIndexPath:indexPath];
cell.cam.highlightedImage = [UIImage imageNamed:#"cam_selected"];
}
You could change the image back when the user deselect the cell.
- (void)tableView:(UITableView *)tableView didDeselectRowAtIndexPath:(NSIndexPath *)indexPath {
TableViewCell2 *cell = [tableView cellForRowAtIndexPath:indexPath];
cell.cam.highlightedImage = [UIImage imageNamed:#"cam_unselected"];
}
2. Persist the selection when the cell is reused.
Again, when the cell is reused, you have to check whether it is selected or not. Then assign the image accordingly.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
TableViewCell2 *cell = [tableView dequeReusableCellWithIdentifier:#"cell"];
BOOL isRowSelected = [indexPath isEqaul:[tableView indexPathForSelectedRow]];
if (isRowSelected) {
cell.cam.highlightedImage = [UIImage imageNamed:#"cam_selected"];
} else {
cell.cam.hightlightedImage = [UIImage imageNamed:#"cam_unselected"];
}
}
Two things I notice here. First you never use true or TRUE in Objective-C. You use BOOL with YES and NO. Second, you rarely need to use dequeReusableCellWithIdentifier: outside tableView:cellForRowAtIndexPath:. Why did you do it there?