How do I respond to touching an empty UITableViewCell? - ios

I'd like to launch my "add item" form in response to touching an empty cell (the next blank cell), sort of like the stock "Reminders" app. didSelectRowAtIndexPath doesn't work for this and I don't have a clue what does.
Thanks

add a button to the tableFooterView
https://developer.apple.com/library/IOs/#documentation/UIKit/Reference/UITableView_Class/Reference/Reference.html

You could add a tap gesture recognizer to the table view, but be sure to test if the user tapped a table view cell or not.

If you wanna the last cell of your table view to be an add button so that you can add a cell directly without putting the table view in edit mode, then here is what you can do:
For the array you use to populate the table view, always make sure the last cell is a dummy object you use to add a row only.
in your -(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath, make sure check whether indexPath.row is equal to [array count], if that's the same, then
insert whatever the object you create to your array at index = [array count]-1.
Call your [tableview reload] method. Then you will see the cell append to the table view.
Hope this helps.

Related

How to update a view added in UITableViewCell?

What I'm doing?
I'm adding dynamic views to my UITableViewCell (which isn't subclassed).
Cell Hierarchy :
UITableView > UITableViewCell > cell.contentView > MainView > ([Number Of PointView] + [Options View]).
Here it is:
When a user will tap "Add Another Point", I'll add a PointView (which will be same as above) :
Y position [ ] X position [ ]
which will be look like this,
What is my logic to get this done?
I'm taking MainView from cell.contentView.
Then fetch last two views (Point View & Options View) added into MainView.
Add Another PointView in MainView.
Update frames for newly added PointView based on last PointView and also update frame of OptionsView.
Resizing height of MainView
And reloading particular cell.
I'm able to get it work, to confirm I've logged frame and subviews for that MainView. But once I tap on "Add Another Point" button again, I found that MainView isn't updated at all?
My simple question is, if I have a MainView (which I fetch from a Cell), can I update it directly or not?
P.S. I already have a poor solution for this is, to remove MainView and recreate new – which I found unnecessary. Any thoughts?
Short answer, yes you can.
cell.contentView is a placeholder. What you are likely running into is an entirely different problem: UITableViewCells are cached, then recycled and reused by the system.
Anytime you respond to cellForRowAtIndexPath, you basically need to reset the content.
I think what you should do. Just make this one cell class
This one other cell subclass
Use this method to insert your rows and also update your data source for table view that is the number of rows in section part
Your + button on click method can be like this..
//Use your own logic what you want to do.
Update your data source
NSIndexPath* index=[NSIndexPath indexPathForRow:[table count]-1 inSection:0];
NSMutableArray* indexPathArray=[[NSMutableArray alloc]init];
[indexPathArray addObject:index];
//index will be your new added point cell. Updating your datasource
[_myTableView insertRowsAtIndexPaths:indexPathArray
withRowAnimation:UITableViewRowAnimationTop];
Make this YES
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath {
// Return YES if you want the specified item to be editable.
return YES;
}

Scroll UITable to specific table item

So i have a UITableview with 3 different tabs setup.
I want to scroll the table to a specific item.
If user added a new item, table to scroll all the way to the bottom because that's where the item will be added.
If user picks one of the items and edits it, it should come back to the same position on the table. Not scrolled to the top or bottom.
This is what I have:
This is a class variable.
NSIndexpath lastScrollY;
In my ViewWillDisappear :
lastScrollY = this.tableView.IndexPathForSelectedRow() ;
In my ViewWillAppear:
if(lastScrollY != null) {
this.tableView.ScrollToRow(lastScrollY, UITableViewScrollPosition.None, true);
}
this does not seem to work.
And that is only for when user selects a saved item.
What about when then add a new item/row to the table?
Please explain in detail as I am new to this.
Thank you for your time!
For after you add a new cell to your tableView, use the same method you did before, but change the scroll position (this code is in Objective-C, but does the same thing as yours. I'll try to help with a translation if you need one):
[tableView scrollToRowAtIndexPath:indexPath
atScrollPosition:UITableViewScrollPositionBottom
animated:true];
You might also want to set lastScrollY in an override of the method
(void) tableView: (UITableView *) tableView didSelectRowAtIndexPath: (NSIndexPath *)indexPath
using the automatically passed in value indexPath to save to lastScrollY.
Lastly, I'm not sure if this will help, but in your current scrollToRow call, you have it scrolling to "none", try having it scroll to UITableViewScrollPositionTop instead. If that still doesn't work, try calling [tableView reloadData] at the end of your viewWillAppear method, which is probably something along the lines of tableView.reloadData() in your language.
Hope this helps!

How to select multiple cells in a table view

I have a table view with multiple cells. When I click on one of the cell it navigates to the next view controller, but my problem is that I cannot select multiple cells.
Could any one please help me on this issue, I want to select two or more cells with two finger tap.
set by code if you set by programming
table.allowsMultipleSelection = YES;
and if you set in xib tick on allowsMultipleSelection
Just add button like checkbox and multiple choose like checkbox.
If you are implementing the tableview programatically then the better way is to create a custom cell which will have button (and obviously other UI components that you need to show in the table view cell) which will work as a checkbox and assign button.tag as indexPath.row which will help you to select multiple rows.
Take a look here --
Below code will go into cellForRowAtIndexPath
YourCustomCell *cell = [tableView dequeueReusableCellWithIdentifier:#"Cell" forIndexPath:indexPath];
cell.button.tag = indexPath.row;
[cell.button addTarget:self action:#selector(multipleCheckAction:) forControlEvents:UIControlEventTouchUpInside];
return cell;
-(void)multipleCheckAction:(UIButton *)sender { //sender.tag will be equal to indexPath.row }
Happy Coding
Since cells are being reused, you need to set the accessory mark to on or off for every cell in the table in the cellForRowAtIndexPath table datasource method.
So the cell.accessoryType cell property should be specified in the cellForRowAtIndexPath and not the didSelectRowAtIndexPath delegate method.
In the didSelectRow, just keep track of the selected rows in an array, and set the cells accessory mark to none or checkmark in the cellForRowAtIndexPath depending on the array value.

Update DataSource from UITextView in UITableView

I have a UITableView and each UITableViewCell contains an editable UITextView.
My data source is a NSMutableArray containing NSMutableDictionary that holds the text value and some styling keys for the text.
How can I (efficiently) make it so that any changes a user makes to the UITextView are updated in the corresponding datasource NSMutableDictionary?
A rather simple way is to utilize the index path of the table, it is NOT the cleanest so it depends on the complexity of your datasource, and if you have multiple tables etc.
What you can do is when the user ends editing the textView or selects another row in tableView, you read the indexPath of the selected row (That requires that the row keeps actually being in the selected state while editing the textView which it should by default). From there you call your update method.
To catch the end of editing you implement
-(void)textViewDidEndEditing:(UITextView *)textView
{
NSIndexPath *selectedpath = [myTable indexPathForSelectedRow];
[self myUpdateMethodForIndexPath:selectedpath];
}
To catch deselect of the table row and the above doesnt get called, you implement
-(void)tableView:(UITableView *)tableView didDeselectRowAtIndexPath:(NSIndexPath *)indexPath
{
[self myUpdateMethodForIndexPath:indexPath];
}
Your update method must then read the value of the textView at the corresponding cell at the indexPath and handle this in the datasource. To care for sections of course you need to correctly handle the indexPath, in the example just the row is used (1 section).
-(void)myUpdateMethodForIndexPath:(NSIndexPath *)editPath
{
UITableViewCell *editCell = [myTable cellForRowAtIndexPath:editPath];
NSString *newText = editCell.theTextView.text;
....
NSMutableDictionary *dict = [myDictArray objectAtIndex:editPath.row];
....
}
First of all, you must assign a tag to each UITextView, to know exactly which UITextView are you refering.
Then you must implement UITextViewDelegate in your view controller which holds the tableview. Then, make this view controller the delegate of each UITextView. Read here how to implement it: UITextViewDelegate reference.
Look for the protocol method that better fits your needs (probably – textView:shouldChangeTextInRange:replacementText:, wich is called each time the text changes in any range.
In the delegate method, you can read the text with UITextView.text property, and assign this value to your data model (the dictionary).
Another possible approach is to use KVO pattern, but it requires more coding and a better understanding both, the pattern and the implementation. Hope it helps!
Make your view controller the delegate of each text view. Listen for appropriate events to get the updated text. Then have the view controller update the data model with the updated text.
If you have custom cells then have the cell be the text view delegate. Then the cell should notify its delegate (the view controller) about the updated text. Of course this requires that your custom cell class define its own delegate protocol and the view controller should make itself the delegate of each cell.
That's as specific as an answer can be for such a vague question.

Why is my UILabel in a UIView in a UITableCellView not updating after a correct database call, (it seems cell reuse related)?

I have a UITableview cell that gets a tally from a core data database. The tallyTable is in a view controller inside a UITab view. I have an NSLog statement that prints out the tally value whenever it gets updated. Another tab has a list to change the source (different day) for the tallies. I am using iOS5 with ARC targeting iOS 4.2.
Here's the problem. When I load the application, the correct tallies for whatever the last selected day show up in the table tab. If I then go to the day tab and change the day and return to the tally tab there is no change in the display. However, the viewWillAppear on the tally tab runs and as the table cycles through cellForIndexPath, my NSLog statement prints out all the correct new values. If I then scroll the top label off the screen and back the label updates to the new value.
I've tried setNeedsLayout and setNeedsDisplay on the UILabel, the UITableViewCell, the UITableView and the view controller loading the table. I tried changing the CellReuse identifier so that it would never reuse a cell.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
CollectionItemTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[CollectionItemTableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
}
NSUInteger row = [indexPath row];
cell.textLabel.text = [[self.collectionKeys objectAtIndex:row] valueForKey:#"collectionTitle"];
NSInteger test1 = indexPath.row + 150;
NSLog(#"tag = %i", test1);
cell.tallyButton.tag = test1;
NSNumber * questionID = [[self.collectionKeys objectAtIndex:row] valueForKey:#"answerID"];
cell.tallyLabel.text = [NSString stringWithFormat:#"%i",[self updatePointTotal:questionID]];
NSLog(#"Collection text should be = %#", [NSString stringWithFormat:#"%i",[self updatePointTotal:questionID]]);
[cell setNeedsLayout];
return cell;
}
I've read over a half dozen other similar questions. Got about three hours invested so far in trying to solve this.
EDIT: I thought I fixed it by using the navigation controller to repush the top level view controller on to the view again. I'll admit now this feels like a classically kludgy hack in every way. When the view is PUSHED everything updates and it is seamless. However, in order to have a fixed footer to make selection settings for the table buttons, I used a UIView with two subviews, a UITableView on top and a simple UIView with four buttons below.
The captions on the buttons need to change with the data source. Now when the view controller is pushed onto the view it obscures my fixed footer view. So, I inserted the fixed footer into the UITableview and everything appeared fine until I scrolled the UITableView and the footer scrolled up with it. The table is basically a tally sheet with buttons next to each item and in the footer is four buttons to note the color of the tallied item. Say the next item was a green lego, you would tap "green" in the footer and the button next to "lego" in the table. When I push the view controller with the two subviews the UITableview labels do not update. Thus the tableview needs to be pushed itself (as far as I can tell).
ANSWER: see comment below but ultimately I needed to reload both the visible UITableView data and the delegate UITableView controller data behind it.
I'll give it a shot. First, are you using ARC? If not, you need to add autorelease when you alloc/init a new cell. Otherwise, it's fine as is.
If I'm understanding your question correctly:
The tableView displays the correct data at app launch
You switch away from the tab with the tableView and change the tableView dataSource
You switch back to the tab with the tableView and you see (via NSLog) that the table cells are reloaded with the correct data yet the old data is still visible in the cells
If you scroll a cell off the display and back forcing it to refresh it contains the correct data
Some thoughts:
the tableView will not reload itself automatically when it's view appears. You need to call [tableView reloadData] whenever the dataSource changes. This is independent of whether the tableView is currently displayed or not. My guess is this alone will solve your problem.
You don't need to call setNeedsLayout on the cell unless you want the cell to relayout its subviews based on the data. You also don't need setNeedsDisplay.
I'm assuming there aren't other complicating factors (such as multiple tableViews displaying the same data) that could confuse things.
If you use prepare for reuse method, remember to over the original method with [super prepareForReuse];
Another method if the above way does not work is re setup cell as describe here.
I use the same method i applied for some of my collection view : we should remove/reset your subview where you create/add it to cell 's content. That mean we need set up data each cell completely for each row.
I move the code reset data value from prepare reuse to where i set value and I worked simply !
In my CustomCell.m :
- (void)configCellWith:(id)item At:(NSUInteger)row {
if (_scrollView) {
[[_scrollView subviews]
makeObjectsPerformSelector:#selector(removeFromSuperview)];
_scrollView = nil;
[_scrollView removeFromSuperview];
}
else {
CGFloat y = labelHeight+15;
float scrollHeight = _imgArray.count*200;
_scrollView=[[UIScrollView alloc]initWithFrame:CGRectMake(10, y,SCREEN_WIDTH-20, scrollHeight)];
_scrollView.scrollEnabled=YES;
_scrollView.userInteractionEnabled=YES;
_scrollView.layer.masksToBounds = YES;
[self.contentView addSubview:_scrollView]; } }
Remember to change your data source appropriately too.

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