iPhone - UITableView - lost data if i go back - iphone

Question

I have a TabBar, NavBar, SearchBar with ScopeBar on my screen. I can search data via a remote server and list the content. So I have a NSMutableArray listContent and a filteredListContent like in the example of Apple (TableSearch - http://developer.apple.com/iphone/library/samplecode/TableSearch/index.html):
Now I added in
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
these line:
testDetailViewController *testDetailViewController = [[TestDetailViewController alloc] initWithNibName:#"TestDetailView" bundle:[NSBundle mainBundle]];
testDetailViewController.title = testClass.name;
testDetailViewController.myKey = testClass.keyId;
[[self navigationController] pushViewController:testDetailViewController animated:YES];
[testDetailViewController release];
testDetailViewController = nil;
Because of the NavigationBar, there is a "back" button. If I click this button, the TableView is empty, no matches/hits.
What I have to do, so the content will still be there?
Does anyone know?
Thanks a lot in advance & Best Regards.
Source Code:
#implementation SearchViewController
#synthesize listContent, filteredListContent, savedSearchTerm, savedScopeButtonIndex, searchWasActive;
- (void)viewDidLoad {
// restore search settings if they were saved in didReceiveMemoryWarning.
if (self.savedSearchTerm) {
[self.searchDisplayController setActive:self.searchWasActive];
[self.searchDisplayController.searchBar setSelectedScopeButtonIndex:self.savedScopeButtonIndex];
[self.searchDisplayController.searchBar setText:savedSearchTerm];
self.savedSearchTerm = nil;
}
}
- (void)viewDidUnload {
// Save the state of the search UI so that it can be restored if the view is re-created.
self.searchWasActive = [self.searchDisplayController isActive];
self.savedSearchTerm = [self.searchDisplayController.searchBar text];
self.savedScopeButtonIndex = [self.searchDisplayController.searchBar selectedScopeButtonIndex];
self.filteredListContent = nil;
}
- (void)dealloc {
[listContent release];
[filteredListContent release];
[super dealloc];
}
- (void)setData {
self.listContent = [NSMutableArray arrayWithCapacity:3];
[self.listContent addObject:[SearchObjects itemWithType:#"AAA" name:#"Test1"]];
[self.listContent addObject:[SearchObjects itemWithType:#"BBB" name:#"Test2"]];
[self.listContent addObject:[SearchObjects itemWithType:#"BBB" name:#"Test3"]];
// create a filtered list
self.filteredListContent = [NSMutableArray arrayWithCapacity:[self.listContent count]];
[self.tableView reloadData];
self.tableView.scrollEnabled = YES;
}
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
//If the requesting table view is the search display controller's table view, return the count of the filtered list, otherwise return the count of the main list.
if (tableView == self.searchDisplayController.searchResultsTableView) {
return [self.filteredListContent count];
} else {
return [self.listContent count];
}
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *kCellID = #"cellID";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:kCellID];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:kCellID] autorelease];
cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
}
/* If the requesting table view is the search display controller's table view, configure the cell using the filtered content, otherwise use the main list. */
SearchObjects *searchObject = nil;
if (tableView == self.searchDisplayController.searchResultsTableView) {
searchObject = [self.filteredListContent objectAtIndex:indexPath.row];
} else {
searchObject = [self.listContent objectAtIndex:indexPath.row];
}
cell.textLabel.text = searchObject.name;
return cell;
}
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
// HERE IS THE SOURCE CODE FOR PUSHING TO THE NEXT VIEW
}
- (void)searchBarSearchButtonClicked:(UISearchBar *)searchBar {
// DO SOME CALCULATIONS… AND THE setData METHOD IS CALLED
}
- (void)filterContentForSearchText:(NSString*)searchText scope:(NSString*)scope {
/* Update the filtered array based on the search text and scope. */
[self.filteredListContent removeAllObjects]; // First clear the filtered array.
/* Search the main list for whose type matches the scope (if selected) and whose name matches searchText; add items that match to the filtered array. */
for (SearchObjects *searchObject in listContent) {
if ([scope isEqualToString:#"All"] || [searchObject.type isEqualToString:scope]) {
NSComparisonResult result = [searchObject.name compare:searchText options:(NSCaseInsensitiveSearch|NSDiacriticInsensitiveSearch) range:NSMakeRange(0, [searchText length])];
if (result == NSOrderedSame) {
[self.filteredListContent addObject:searchObject];
}
}
}
}
- (void)filterContentForScope:(NSString*)scope {
/* Update the filtered array based on the search text and scope. */
[self.filteredListContent removeAllObjects]; // First clear the filtered array.
/* Search the main list for whose type matches the scope (if selected); add items that match to the filtered array. */
for (SearchObjects *searchObject in listContent) {
if ([scope isEqualToString:#"All"] || [searchObject.type isEqualToString:scope]) {
[self.filteredListContent addObject:searchObject];
}
}
}
- (BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchString:(NSString *)searchString {
[self filterContentForScope:[[self.searchDisplayController.searchBar scopeButtonTitles] objectAtIndex:[self.searchDisplayController.searchBar selectedScopeButtonIndex]]];
// Return YES to cause the search result table view to be reloaded.
return YES;
}
- (BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchScope:(NSInteger)searchOption {
[self filterContentForScope:[[self.searchDisplayController.searchBar scopeButtonTitles] objectAtIndex:searchOption]];
// Return YES to cause the search result table view to be reloaded.
return YES;
}
#end

Answer 1

You generally don't have to do anything in this case, the data should remain in place. Is there something which is unloading the data? Do you have a viewWillDisappear function which is unloading your array? Are you doing some of the array setup in viewWillAppear.
Put a log statement at the start of your methods to find out when they are being called, it will give you a clearer picture of what's happening.

Answer 2

It is solved. It was a problem which is not obvious with the given source code.
There was an error in my logic.