I just implemented a Load More button into the footer of my tableView, but the footer is always scrolling with the table. The style of my tableView is UITableViewStylePlain.
Please could you tell me where I am going wrong.
- (UIView *)tableView:(UITableView *)tableView viewForFooterInSection:(NSInteger)section {
UIView *footerView = nil;
if(footerView == nil) {
footerView = [[[UIView alloc] init] autorelease];
footerView.backgroundColor = [UIColor clearColor];
UIButton *button = [[UIButton alloc] init];
button.layer.cornerRadius = 7;
[button setFrame:CGRectMake(10, 3, 300, 44)];
[button setTitle:#"Load 20 more" forState:UIControlStateNormal];
[button.titleLabel setFont:[UIFont boldSystemFontOfSize:20]];
[button setBackgroundColor:[UIColor whiteColor]];
[button.titleLabel setTextColor:[UIColor blackColor]];
[button addTarget:self action:#selector(load20More) forControlEvents:UIControlEventTouchUpInside];
[footerView addSubview:button];
[button release];
}
if ([songInfo count] > 20 && count < 100) {
return footerView;
}
else
return nil;
}
First of all, tableView:viewForFooterInSection does not define a footer for the table, it defines a footer for the section in the table. You can have multiple section footers in one table. In the case where your table is only one section, using this method will be functionally equivalent to adding a table footer, but it is NOT meant to be the table's footer. It is much better practice to use the actual table footer if that's what you want, which can be accomplished by simply assigning a view to the UITableView's tableFooterView property.
However, table footers (section footers AND table footers) are both built to scroll with your table. If you are looking to implement a "footer" that sticks to the bottom of the screen and does not scroll with the table, your best bet is to resize your UITableView smaller to make room for your "footer", and add a new view to sit in the spot you just cleared for it. That way, it will stick in place, and the scrollable region in your table will not overlap with the "footer".
Here if you use the table view in-built delegate method,
tableView(_ tableView: UITableView, viewForFooterInSection section: Int) -> UIView?,
it will appear as fixed at the bottom of the view and it doesn't care about the height of the table view. Even though if you set tableView.tableFooterView?.isUserInteractionEnabled = true it won't work as you want. So as the solution for this, you have to set the table footer view on viewDidLoad() (as you are setting delegate and datasource in this method).
let cell = tableView.dequeueReusableCell(withIdentifier: "MyFinanceTableViewFooterCell") as! MyFinanceTableViewFooterCell
tableView.tableFooterView = cell
And this will work as you wish.
This is a work around. For plain UITableView, if you want the footer to be not sticky at the bottom, try using the footer in a section with no header. Example: we have one section with headerView and footerView. try using two sections, first section -> with headerView and nil(footer), second section -> nil(header) and footerView.
Related
I have a UITableView, I can add and delete cell to this table. I also have two buttons. 1 button adds "1" to the cell's text, Which is 1 so basically it counts when pressing the + button and subs when pressing the - button. My problem is with the very last cell. If i add 5 cells, its the 5th cell that has the problem. If i add 200 cells its the 200th cell, etc. The problem is when i press the - button, all the other cells keep turning blue when pressed, and this button stops turning blue. It stays white when i press it when the cells text is 0. I want it to keep turning blue like all the other cells when pressed. Here is my code:
- (IBAction)subtractLabelText:(id)sender
{
cell = (UITableViewCell*)[sender superview];
if ( [[cell.textLabel text] intValue] == 0){
[newBtn setEnabled:NO];
}
else{
cell.textLabel.text = [NSString stringWithFormat:#"%d",[cell.textLabel.text
intValue] -1];
[newBtn setEnabled:YES];
}
}
This method is hooked up to the sub "-" button. Also, when i press the button when the text is = 0, the button is there but when i press it, it selects the cell and the table cell turns blue as if i selected that! Please help! Thanks everybody!
cellForRow:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:
(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = #"Cell";
cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil)
{
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault
reuseIdentifier:CellIdentifier];
}
cell.imageView.image = [imageArray objectAtIndex:indexPath.row];
cell.textLabel.text = [cells objectAtIndex:indexPath.row];
newBtn = [[UIButton alloc]init];
newBtn=[UIButton buttonWithType:UIButtonTypeRoundedRect];
[newBtn setFrame:CGRectMake(260,20,55,35)];
[newBtn addTarget:self action:#selector(subtractLabelText:)
forControlEvents:UIControlEventTouchUpInside];
[newBtn setTitle:#"-" forState:UIControlStateNormal];
[newBtn setEnabled:YES];
[cell addSubview:newBtn];
subBtn = [[UIButton alloc]init];
subBtn=[UIButton buttonWithType:UIButtonTypeRoundedRect];
[subBtn setFrame:CGRectMake(200,20,55,35)];
[subBtn addTarget:self action:#selector(addLabelText:)
forControlEvents:UIControlEventTouchUpInside];
[subBtn setTitle:#"+" forState:UIControlStateNormal];
[subBtn setEnabled:YES];
[cell addSubview:subBtn];
return cell;
}
Based on your cellForRowAtIndexPath method, you are creating and adding new buttons to each cell regardless of whether they are being reused or 'brand new'.
Your code is doing something like this:
Check if there is a cell to be dequeued/reused
If yes, grab a reference to it. If no, create a new one.
Add buttons XYZ to the cell (your mistake is here)
Return the cell for the tableview to use
Imagine that in step 2, if you a reusing an existing cell, this cell already has the buttons XYZ added to it so you are essentially adding two extra button to it when you didn't need to.
You should move the code that sets up the cell buttons to inside the if (cell == nil) loop so the buttons are only created and added to the content view if you are initialising a new cell object.
Also make sure you look at the additional comments below which are not directly related to your question but may be relevant nonetheless.
==================================================================
[EDIT - ANSWER ABOVE, BUT THIS IS ALSO RELEVANT SO I LEFT IT HERE]
This will not solve your problem, but you should be adding your buttons to the cell's contentview instead of directly to the cell, i.e.:
[cell.contentView addSubView:buttonABC];
Once that's done, you will need to call superview twice to get the cell reference in your subtract/add method:
cell = (UITableViewCell*)[[sender superview] superview];
From Apple's documentation on UITableViewCell
The content view of a UITableViewCell object is the default superview
for content displayed by the cell. If you want to customize cells by
simply adding additional views, you should add them to the content
view so they will be positioned appropriately as the cell transitions
into and out of editing mode.
At a guess, I'd say it has to do with how the UITableViewCells are being reused, in that the UI doesn't 'know' about the subview buttons on those cells.
Try commenting out the code in -cellForRowAtIndexPath that dequeues the reusable cells (so in effect you're always creating a new UITableViewCell regardless of whether cell==nil or not).
Edit:
You're referencing newBtn in -subtractLabelText, but this is an ivar that doesn't necessarily refer to the button that sent the message. Try [sender setEnabled:NO] instead.
I have a problem in that when I add rows (with animation) to my table, the section headers do not move. I create the section headers in viewDidLoad like so:
CGRect header = [self.tableView rectForHeaderInSection:0];
UILabel *label = [[UILabel alloc] initWithFrame:headerFrame];
[label setText:#"---"];
label.backgroundColor = [UIColor clearColor];
[label setFont:headerFont];
[label setTextColor:[UIColor blueColor]];
[self.tableView addSubview:label];
[label release];
Am I supposed to add them in a different manner? (And yes I realize that these are custom table headers, that's how I want them)
And I have a user add rows by using a picker. The rows are added like so:
NSIndexPath* path = [NSIndexPath indexPathForRow:chan.channel_number inSection:section_number];
NSArray* row_to_add = [[NSArray alloc] initWithObjects:path , nil];
[self.tableView insertRowsAtIndexPaths:row_to_add withRowAnimation:UITableViewRowAnimationRight];
And the row gets added just fine, but my header views dont budge. How can I make my headers reposition themselves?
You need to use a real header title. You can use the delegate method tableView:viewForHeaderinSection: and return a UILabel.
If you use:
- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section
Everything should be fine
I think you can try -reloadSections:withRowAnimation:. This shall cause a reload of your section and its header and footer views.
I have a table view wherein the number cells are not fixed and will keep on changing. I have to show two action buttons after my last cell in the table footer. How can I place them properly after my last cell? I know the pixel spacing between last cell and these buttons. Any code sample will be really helpful.
Have you tried sticking them in a view and setting that as the footer view?
You need to give it the correct height before you add it; the width is automatically set to the width of the table. Either set it to a sensible width (e.g. 320) and use autoresizing or use a custom UIView subclass and implement -layoutSubviews.
You could always add two buttons to the final cell.
- (NSInteger)tableView:(UITableView *)aTableView numberOfRowsInSection:(NSInteger)section {
return [myCellDataArray count]+1;
}
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
UITableViewCell *cell = nil;
if (indexPath.row > [myCellDataArray count]) {
cell = [tableView dequeueReusableCellWithIdentifier:#"Button Cell"];
if (cell == nil) {
UIButton *firstButton = [[UIButton alloc] init];
//customization
UIButton *secondButton = [[UIButton alloc] init];
//customization
[cell addSubView:firstButton];
[cell addSubView:firstButton];
}
} else {
// normal stuff
}
If you want to customize existing buttons you need to set it's tag to something unique, i.e. firstButton.tag = 100 and then set firstButton by firstButton = (UIButton *)[cell viewWithTag:100];. Make sure you define firstButton so that it's in scope!
Hope this helps!
UPDATE 4.0
Seems like iOS 4.0 changed something here. Same code producing incorrect backgrounds for section header in the described scenario is working with 4.0 according to my first quick check!
Original
I have a UITableView grouped style with custom header and footer view. Inside the footer I put a UILabel and a UIButton.
Clicking on the button hides or show some rows, updates the UILabel in the footer view and finally resizes footer view.
Basically everything is working fine. BUT the text ion the label is not updated on the screen. It is updated in the UILabel text property, but only if I scroll the section footer out of the visible area and scroll it back, it is updated. So it's a typical redraw problem here of the UITableView.
I tried every method to force update like needsLayout etc. Nothing helped.
I have seen some related questions but with some different behaviour and no solution. Any help/ideas?
Thanks, Gerd
UPDATE:
My problems occurs with section footer, so here is my viewForFooterInSection.
Basically I want to collapse/expand a section, but not completely (that was an easy thing) instead only the empty cell (ItemSize empty). The footerView is large if it is collapsed and will shrink if it is expanded. Furthermore the label text will change.
- (UIView *)tableView: (UITableView *)tableView viewForFooterInSection: (NSInteger)section{
NSLog(#"viewForFooterInSection section:%i", section);
UIButton *myView;
UILabel *label;
if ([[[self.sectionStatus objectAtIndex:section] valueForKey:#"collapseStatus"] isEqual:#"collapse"]){
myView = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 320, 52)];
[myView setBackgroundImage:[UIImage imageNamed:#"ItemViewFooter.png"] forState:UIControlStateNormal];
label = [[UILabel alloc] initWithFrame:CGRectMake(20, 32, 300, 20)];
label.text = NSLocalizedString(#"list_expand",#"");
} else { //is expanded
myView = [[UIButton alloc] initWithFrame:CGRectMake(0, 0, 320, 21)];
[myView setBackgroundImage:[UIImage imageNamed:#"ListCollapseExpand.png"] forState:UIControlStateNormal];
label = [[UILabel alloc] initWithFrame:CGRectMake(20, 1, 300, 20)];
label.text = NSLocalizedString(#"list_collapse",#"");
}
myView.tag=section;
[myView addTarget:self action:#selector(collapseExpandAction:) forControlEvents:UIControlEventTouchUpInside];
myView.backgroundColor = [UIColor clearColor];
myView.adjustsImageWhenHighlighted = NO;
myView.showsTouchWhenHighlighted = YES;
label.textColor = FONTCOLOR;
label.font = [UIFont systemFontOfSize:14];
label.numberOfLines = 1;
label.textAlignment = UITextAlignmentCenter;
label.backgroundColor = [UIColor clearColor];
[myView addSubview:label];
return myView;
};
In the button action method I store status of section collapse/expand and the number of displayed rows. Than I delete or insert rows. (It has to be with insert/delete because I need the animation).
- (void) collapseExpandSection: (NSInteger) section{
NSMutableArray *paths = [NSMutableArray arrayWithCapacity:10];
NSInteger row;
NSInteger numberOfDisplayedItems=[[[self.sectionStatus objectAtIndex:section] valueForKey:#"numberOfDisplayedRows"] intValue];
id <NSFetchedResultsSectionInfo> sectionInfo = [[fetchedResultsController sections] objectAtIndex:section];
NSInteger numberOfAllItems=[sectionInfo numberOfObjects];
Item *tmpItem=nil;
NSSet *itemsWithSizes=nil;
//filter not used cells
for ( row = 0; row < numberOfAllItems; row++ ) {
tmpItem=[fetchedResultsController objectAtIndexPath:[NSIndexPath indexPathForRow:row inSection:section]];
NSPredicate *predicate = [NSPredicate predicateWithFormat:#"itemSize != nil"];
NSSet *itemsWithSizes = [tmpItem.itemSizes filteredSetUsingPredicate:predicate];
if ([itemsWithSizes count]==0){
[paths addObject:[NSIndexPath indexPathForRow:row inSection:section]]; //all unused cells
};
}
if (numberOfDisplayedItems == numberOfAllItems){ //currently all shown => Collapse
[self.tableView beginUpdates];
[[self.sectionStatus objectAtIndex:section] setValue:[NSNumber numberWithInt:(numberOfDisplayedItems-[paths count])] forKey:#"numberOfDisplayedRows"];
[[self.sectionStatus objectAtIndex:section] setValue:#"collapse" forKey:#"collapseStatus"];
[self.tableView deleteRowsAtIndexPaths:paths withRowAnimation:UITableViewRowAnimationFade];
[self.tableView endUpdates];
} else { //Not all shown so expand with the unused cells
[[self.sectionStatus objectAtIndex:section] setValue:[NSNumber numberWithInt:(numberOfDisplayedItems+[paths count])] forKey:#"numberOfDisplayedRows"];
[[self.sectionStatus objectAtIndex:section] setValue:#"expand" forKey:#"collapseStatus"];
[self.tableView beginUpdates];
[self.tableView insertRowsAtIndexPaths:paths withRowAnimation:UITableViewRowAnimationFade];
[self.tableView endUpdates];
}
return;
};
Doing all this works fine in general. After the blocks begin/endupdate the viewForFooter is called for every section and the label text is set correct in the property. However the display doesn't update correctly. As soon as a redisplay is forced (srolling out- scrolling in) the display is OK.
There 2 problems.
First problem is that section footer not updated.
Try call [tableView reloadData] or [tableView reloadSections:sections withRowAnimation:UITableViewRowAnimationFade] after your update (may be with dalay).
Second problem is memory leaks in myView and label.
Also why do you use label when you can use button's internal label?
P.S. Don't allocate UIButton object directly because it is factory. Call [UIButton buttonWithType:UIButtonTypeCustom] instead.
Upd: Another way to update is to update footer directly by accessing footer views.
- (void) collapseExpandSection: (NSInteger) section{
Check that section is actualy your button
- (void) collapseExpandSection: (UIButton*) sender{
// Do update of sender here
// Do other stuff
}
Also you can try next trick: create UIView object in delegate, add your button and label on it and return instaed of buttom view itself.
My problem was that I was expanding the Section header to show a search bar, but it wouldn't redraw the view until I scrolled the UITableView.
I had my own SectionHeader class that subclassed UIView and controlled the searching stuff.
After my animation, I just used this to force an update. It's not pretty but it works.
CGPoint point = CGPointMake(((UIScrollView *)self.superview).contentOffset.x,
((UIScrollView *)self.superview).contentOffset.y+1);
[((UIScrollView *)self.superview) setContentOffset:point animated:NO];
point = CGPointMake(((UIScrollView *)self.superview).contentOffset.x,
((UIScrollView *)self.superview).contentOffset.y-1);
[((UIScrollView *)self.superview) setContentOffset:point animated:NO];
Basically force the UITableView to scroll down 1 pixel and up 1 pixel.
I had an issue just like this where I wanted to update the section header after inserting a new row. I found that calling tableView reloadSections() method with an animation setting of .None after I call the insertRows method worked for me (both calls in the same tableView update block). I got the insert animation I wanted and also the section header was updated.
I'm currently trying to implement a editable details view using a grouped UITableView. I'd like it to look like the Contacts application:
in viewing-state it should display the header as plain label (in Contacts it's the name with TRANSPARENT background).
in editing-state it should display the header as editable UITableViewCell (in Contact's the tableHeader? changes from just the plain text with transparent background to a standard UITableViewCell with white background).
I'm not really sure what the best way is the achieve this. First I've tried to add the header as UILabel tableHeaderView (which works great), but then I cannot switch this to a UITableViewCell. A possibility would be to remove the header and add a new section when entering editing mode.
Currently I'm trying to always use a UITableViewCell and make it transparent in viewing mode and switch it to default in editing mode. However, I haven't been able to make the UILabel of the UITableViewCell (which is in UITableViewCellStyleDefault) transparent (although I did manage to make the UITableViewCell transparent, but not the textLabel inside it).
What is the best way to implement this behavior?
I've done this too (although a moot point with the changes to the Contacts app in iOS4!) My solution uses two different header views and switches between them based on isEditing:
- (UIView *)infoHeaderAnimated:(BOOL)animated {
UIView *header = [[[UIView alloc] initWithFrame:CGRectMake(0.0, 0.0, 320.0, 90.0)] autorelease];
UILabel *label = [[UILabel alloc] initWithFrame:CGRectMake(98.0, 41.0, 221.0, 21.0)];
label.font = [UIFont boldSystemFontOfSize:17.0];
label.backgroundColor = [UIColor clearColor];
label.text = baseEntity.labelText;
[header addSubview:label];
[label release];
return header;
}
- (UIView *)editingHeaderAnimated:(BOOL)animated {
UIView *header = [[[UIView alloc] initWithFrame:CGRectMake(0.0, 0.0, 320.0, 90.0)] autorelease];
UITableView *tv = [[UITableView alloc] initWithFrame:CGRectMake(78.0, 10.0, 240.0, 90.0) style:UITableViewStyleGrouped];
tv.backgroundColor = [UIColor clearColor];
tv.dataSource = self;
tv.delegate = self;
tv.rowHeight = 62.0; //### height of cell and frame depend on elements
tv.tag = kEditingHeaderTag;
editingHeaderTableView = [tv retain];
[header addSubview:tv];
[tv release];
return header;
}
What you are trying to do is very standard, consider implementing these protocols in the UITableViewDatasource, especially the titleForHeaderInSection & commitEditingStyle:
Configuring a Table View
– tableView:cellForRowAtIndexPath: required method
– numberOfSectionsInTableView:
– tableView:numberOfRowsInSection: required method
– sectionIndexTitlesForTableView:
– tableView:sectionForSectionIndexTitle:atIndex:
– tableView:titleForHeaderInSection:
– tableView:titleForFooterInSection:
Inserting or Deleting Table Rows
– tableView:commitEditingStyle:forRowAtIndexPath:
– tableView:canEditRowAtIndexPath:
Remember to choose the type of your TableView as Group instead of Plain in the Interface Builder.