Reputation: 5332
I have a UITableView, and it displays data received from a WiFi-connected device.
I want to do the fairly bog-standard gesture response of dragging a table down, then releasing it, to trigger an update.
I guess I could attach a swipe gesture recognizer to the table's substrate view, but I'm wondering if there is a way to intercept this gesture directly from the table itself.
META:
I've been looking through the various docs and whatnot. I haven't had to do this before, so I never gave it any thought. Now I see that I probably should have thought about it.
If this is an obvious solution, I don't mind being told so, as long as you help me to find the "obvious" remedy. I'll delete this question if it's a bad one.
However, I haven't found a solution, and I'm usually fairly good at that kind of thing.
UPDATE I changed the title to better reflect what I'm asking.
Upvotes: 0
Views: 880
Reputation: 5332
This is what I ended up doing. Even though it is not the most "legal" way to do things, it is still highly effective, and absurdly simple:
I set up a scrollview delegate trap, like so, and added it to the delegate class:
//*******************************************
// Reacts to the table's scroller being changed.
- (void)scrollViewWillEndDragging:(UIScrollView *)scrollView
withVelocity:(CGPoint)velocity
targetContentOffset:(inout CGPoint *)targetContentOffset {
#ifdef DEBUG
NSLog ( @"MyViewController::scrollViewWillEndDragging:%@withVelocity:(%f,%f)targetContentOffset:(%f,%f)",scrollView,velocity.x, velocity.y, targetContentOffset->x, targetContentOffset->y );
#endif
// We have to have had a "hard pull South" to trigger a refresh of the objects.
if ( (velocity.y < 0) && ([scrollView contentOffset].y < -60) ) {
#ifdef DEBUG
NSLog ( @"We will perform a new refresh." );
#endif
}
}
The "-60" is because I'm looking for the best offset before I set it into a static.
Upvotes: 0
Reputation: 879
The totally native way to do it is to use a UITableViewController in your UIViewController, e.g.
{
tableViewController = [[UITableViewController alloc] init];
[tableViewController setTableView:myTableView];
refreshControl = [[UIRefreshControl alloc] init];
[tableViewController setRefreshControl:refreshControl];
[refreshControl addTarget:self action:@selector(refresh:) forControlEvents:UIControlEventValueChanged];
}
Upvotes: 7
Reputation: 14030
If you add a UIScrollViewDelegate
to your UITableView
, you can respond to scrollViewDidScroll:
events. A negative contentOffset.y
value indicates that your user has pulled down at the top of your tableview.
Upvotes: 1