UISearchBar not visible until scroll down
I added a UISearchBar programmatically to my tableHeaderView but it doesn't show on view load. There's just a blank space above my table content. When I scroll down a little bit, it appears. I changed the background color of the tableHeaderView to see if it visible at all - I could see the changed color, so it seems the searchBar itself is invisible. Any ideas?
Here's my code:
- (void)viewDidLoad
{
[super viewDidLoad];
...
// Initialize the refresh control.
[self.refreshControl addTarget:self
action:@selector(refreshData)
forControlEvents:UIControlEventValueChanged];
// Suchelemente erzeugen
self.searchBar = [UISearchBar new];
self.searchDC = [[UISearchDisplayController alloc] initWithSearchBar:self.searchBar contentsController:self];
self.searchDC.searchResultsDelegate = self;
self.searchDC.delegate = self;
self.searchDC.searchResultsDataSource = self;
self.tableView.tableHeaderView = self.searchBar;
// some attempts to make it visible
self.searchBar.hidden = NO;
self.searchBar.layer.hidden = NO;
[self.searchBar sizeToFit];
}
Ok, found out, that the refresh control causes the problem. In viewWillAppear a method is called which updates the title of the refresh control. When I comment this line, the searchbar appears:
self.refreshControl.attributedTitle = [[NSAttributedString alloc] initWithString:title];
So, how to make them both work??
Create a refresh control and set this as tableview's refresh control. In this way, the attributed text of the self.refreshcontrol is not set.
UIRefreshControl *refresh = [[UIRefreshControl alloc] init];
refresh.attributedTitle = [[NSAttributedString alloc] initWithString:GetLocalizedString(@"REFRESH_TO_RELEASE_TITLE", nil)];
[refresh addTarget:self action:@selector(refreshViewPulled:) forControlEvents:UIControlEventValueChanged];
self.refreshControl=refresh;
The issue is because your trying to add 2 things to the same spot because you never really specified a frame for either, even though the UIResultsController knows where it goes, it can be altered, and the UIControlEventValueChanged [dragging down] is probably causing discrepancies with the frames changing. So I would suggest implementing your search bar through storyboard since you stated you are using it. Drag and drop a Search Display Controller below the Navigation Bar but above the Table View, you will see your cursor change to a green plus, that means you can drop it there (which in this case is the tableViewHeader):
Then you should be able to continue pragmatically altering the UIRefreshControl per normal
-(void)viewDidLoad {
self.refreshControl = [[UIRefreshControl alloc] init];
self.refreshControl.backgroundColor = [UIColor clearColor];
self.refreshControl.tintColor = [UIColor purpleColor];
[self.refreshControl addTarget:self
action:@selector(refreshView:)
forControlEvents:UIControlEventValueChanged]
self.refreshControl.attributedTitle = [[NSAttributedString alloc] initWithString:@"Pull down to Refresh.."];
}
Now there should be no conflicting frame changes to two items added to the same location.
I had the same problem. I fixed it by pragmatically adjusting the content offset so that rubber band scrolling animation is triggered, causing the UISearchBar to reappear.
If it is invisible, try this:
[self.tableView setContentOffset:CGPointMake(0, -1) animated:NO];
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