I'm trying to add an activity indicator to certain cells in my UITableView. I do this successfully in the method didSelectRowAtIndexpath using
CGRect CellFrame = CGRectMake(260, 10, 20, 20);
actindicator = [[UIActivityIndicatorView alloc]initWithFrame:CellFrame];
[actindicator setHidesWhenStopped:NO];
[actindicator setActivityIndicatorViewStyle:UIActivityIndicatorViewStyleGray];
actindicator.tag =1;
[[cell contentView] addSubview:actindicator];
The catch is I need to control these multiple activity indicators from ANOTHER METHOD. I figured a property was a way to do this however by initialising a new instance of actIndicator every time, I loose reference's to all but the 'latest' init of the activity indicator thus meaning I can only control one.
What do i need to do here (if even possible?) to maintain reference to all the actIndicators so i can begin animating ALL of them? Or Can I somehow use the actindicator.tag to control some form of reference.
Many thanks for any help.
EDIT: (Derived from answer) to access all Instances of Activity indicator with a tag of 1 in tableView (visible cells only) can use below from another method:
for (UITableViewCell *cell in [self.tableView visibleCells]) {
UIActivityIndicatorView *actView = (UIActivityIndicatorView *)[cell.contentView
viewWithTag:1];
[actView startAnimating];
activityFlag = 1;
}
The method above will cycle through all visible cells and start animating the activity indicator.
To handle the case of the tableview being scrolled, I re-animate the indicators using the method below which is in cellForRowAtIndexPath. cellStateKey simply indicates if the cell has a checkmark next to it, if it does have a checkmark and my activityflag (async webserver call in progress)is set..then i want to continue animating.(technically re-start animation, as scrolling tableview stops it)
if ([[rowData objectForKey:cellStateKey] boolValue]) {
cell.accessoryType = UITableViewCellAccessoryCheckmark;
if(cell.accessoryType == UITableViewCellAccessoryCheckmark &&activityFlag ==1){
for (UIView *sub in [[cell contentView] subviews]) {
if (sub.tag == 1) {
UIActivityIndicatorView *acView = (UIActivityIndicatorView *)
[cell.contentView viewWithTag:1];
[acView startAnimating];
}
}
As mentioned in origional question I initialise my activity indicators (and remove activity indicators aswell if required) in the method didSelectRowAtIndexPath
You can add UIActivityIndicatorView as cell's accessoryView.
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
UIActivityIndicatorView *spinner = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
spinner.frame = CGRectMake(0, 0, 24, 24);
UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
cell.accessoryView = spinner;
[spinner startAnimating];
[spinner release];
}
A simple way to do this (assuming you're adding the indicator as in your code) is to first get a collection of the visible cells (or rows) in your table, by calling [tableView visibleCells]
. Then iterate through the cells like this:
for (UITableViewCell *cell in [tableView visibleCells]) {
for (UIView *sub in [cell subViews]) {
if (sub.tag == 1) { // "1" is not a good choice for a tag here
UIActivityIndicatorView *act = (UIActivityIndicatorView *)sub;
[act startAnimating]; // or whatever the command to start animating is
break;
}
}
}
There's more complexity for you to deal with: in your original code, you need to make sure you're not adding an additional activity indicator to a pre-existing cell each time cellForRowAtIndexPath
is called, and you need to account for the situation where the user might scroll the table at a later point, exposing cells that do not have their activity indicator turned on.
You need to make a custom UITableViewCell by extending it. Then have a UIActivityIndicatorView as a member of that Cell. Then you can access it and control it on a cell by cell basis.
Assuming that activity view indicator tag is unique in the cell.contentView you can try something like:
UITableViewCell *cell = [tableview cellForRowAtIndexPath:indexpath];
UIActivityIndicatorView *acView = (UIActivityIndicatorView *)[cell.contentView viewWithTag:1];
//acView will be your activitivyIndicator
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