UITableViewCell from contentView subview - ios5

I have created the cells with labels and using checkaMarksAccessory. The few last cells have UITextFields which can user modifi, and those have selector on UIControlEventEditingDidEnd where i want change the state of the cell to checked.
How can i get the cell in the selector? Doesn't have the object some parentView?
The way i inserting the object to cell.
UITextField *textfield = [[UITextField alloc] initWithFrame:CGRectMake(10, 25, 200, 30)];
[textfield setBorderStyle:UITextBorderStyleRoundedRect];
[textfield addTarget:self action:#selector(vybavaDidFinishEdit:) forControlEvents:UIControlEventEditingDidEnd];
[cell.contentView addSubview:textfield];

I'm not sure if it's safe to assume cell.contentView.superview == cell. Might Apple change this? I doubt it. But, I don't see anywhere in the documentation that says a cell's content view is a direct subview of the cell.
If you've added a UIGestureRecognizer to one of your subviews of the cell's content view, then you can get a reference to the cell with:
NSIndexPath *indexPath = [self.tableView indexPathForRowAtPoint:[gestureRecognizer locationInView:self.tableView]];
UITableViewCell *cell = [self.tableView cellForRowAtIndexPath:indexPath];
Table View Animations and Gestures sample code uses indexPathForRowAtPoint: this way.
If you must traverse superviews, I think using a function like the one below is a bit safer.
UITableViewCell *ACMContentViewGetCell(UIView *view)
{
while ((view = view.superview)) {
if ([view isKindOfClass:[UITableViewCell class]]) {
return (UITableViewCell *)view;
}
}
return nil;
}
But that function still assumes contentView is within its cell, which I also didn't see anywhere in the documentation.
So perhaps, the best solution is to rearchitect your code so that you don't need to get cell from contentView, or if you must, then add an instance variable from the subview of contentView to cell.

ok so the way is to use superview. The superview is component which own the object. If i want get the UITableViewCell from UITextField i used [[UITextField superview] superview].

Related

How do I add a UIActivity Indicator to every Cell and maintain control of each individual indicator

I'm trying to add an activity indicator to certain cells in my UITableView. I do this successfully in the method didSelectRowAtIndexpath using
CGRect CellFrame = CGRectMake(260, 10, 20, 20);
actindicator = [[UIActivityIndicatorView alloc]initWithFrame:CellFrame];
[actindicator setHidesWhenStopped:NO];
[actindicator setActivityIndicatorViewStyle:UIActivityIndicatorViewStyleGray];
actindicator.tag =1;
[[cell contentView] addSubview:actindicator];
The catch is I need to control these multiple activity indicators from ANOTHER METHOD. I figured a property was a way to do this however by initialising a new instance of actIndicator every time, I loose reference's to all but the 'latest' init of the activity indicator thus meaning I can only control one.
What do i need to do here (if even possible?) to maintain reference to all the actIndicators so i can begin animating ALL of them?
Or Can I somehow use the actindicator.tag to control some form of reference.
Many thanks for any help.
EDIT: (Derived from answer) to access all Instances of Activity indicator with a tag of 1 in tableView (visible cells only) can use below from another method:
for (UITableViewCell *cell in [self.tableView visibleCells]) {
UIActivityIndicatorView *actView = (UIActivityIndicatorView *)[cell.contentView
viewWithTag:1];
[actView startAnimating];
activityFlag = 1;
}
The method above will cycle through all visible cells and start animating the activity indicator.
To handle the case of the tableview being scrolled, I re-animate the indicators using the method below which is in cellForRowAtIndexPath. cellStateKey simply indicates if the cell has a checkmark next to it, if it does have a checkmark and my activityflag (async webserver call in progress)is set..then i want to continue animating.(technically re-start animation, as scrolling tableview stops it)
if ([[rowData objectForKey:cellStateKey] boolValue]) {
cell.accessoryType = UITableViewCellAccessoryCheckmark;
if(cell.accessoryType == UITableViewCellAccessoryCheckmark &&activityFlag ==1){
for (UIView *sub in [[cell contentView] subviews]) {
if (sub.tag == 1) {
UIActivityIndicatorView *acView = (UIActivityIndicatorView *)
[cell.contentView viewWithTag:1];
[acView startAnimating];
}
}
As mentioned in origional question I initialise my activity indicators (and remove activity indicators aswell if required) in the method didSelectRowAtIndexPath
You can add UIActivityIndicatorView as cell's accessoryView.
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
UIActivityIndicatorView *spinner = [[UIActivityIndicatorView alloc] initWithActivityIndicatorStyle:UIActivityIndicatorViewStyleGray];
spinner.frame = CGRectMake(0, 0, 24, 24);
UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
cell.accessoryView = spinner;
[spinner startAnimating];
[spinner release];
}
A simple way to do this (assuming you're adding the indicator as in your code) is to first get a collection of the visible cells (or rows) in your table, by calling [tableView visibleCells]. Then iterate through the cells like this:
for (UITableViewCell *cell in [tableView visibleCells]) {
for (UIView *sub in [cell subViews]) {
if (sub.tag == 1) { // "1" is not a good choice for a tag here
UIActivityIndicatorView *act = (UIActivityIndicatorView *)sub;
[act startAnimating]; // or whatever the command to start animating is
break;
}
}
}
There's more complexity for you to deal with: in your original code, you need to make sure you're not adding an additional activity indicator to a pre-existing cell each time cellForRowAtIndexPath is called, and you need to account for the situation where the user might scroll the table at a later point, exposing cells that do not have their activity indicator turned on.
You need to make a custom UITableViewCell by extending it. Then have a UIActivityIndicatorView as a member of that Cell. Then you can access it and control it on a cell by cell basis.
Assuming that activity view indicator tag is unique in the cell.contentView you can try something like:
UITableViewCell *cell = [tableview cellForRowAtIndexPath:indexpath];
UIActivityIndicatorView *acView = (UIActivityIndicatorView *)[cell.contentView viewWithTag:1];
//acView will be your activitivyIndicator

Table Cell SubView Iteration Not Finding TextField

I've created a table where each cell holds both a text label and a text field. I'm adding the textfields as such [cell addSubview:passwordField]; and from a visual perspective they appear and are editable, etc....
The problem arises when I attempt to retrieve the entered values from the textfields. I iterate over the cells and try to grab the subview (IE the textfield), however, my iteration only discovers the text label.
Here is the code I'm using to search:
for(NSInteger i =0; i < [tableView numberOfRowsInSection:0]; i++){
NSIndexPath *path = [NSIndexPath indexPathForRow:i inSection:0];
UITableViewCell *cell = [tableView cellForRowAtIndexPath:path];
UIView* subView = [[cell.contentView subviews]lastObject]; // I've also tried object at index here
// Anything beyond this is just matching....
Another approach I took was recursively searching the subviews, but, again that yielded no results.
You have added your textField on subView of cell.
[cell addSubview:passwordField];
While you're trying to find it on cell.contentView.
Add your textField as a subView of cell.Contentview
[cell.contentView addSubview:passwordField];
And find it in this way -
for(UIView *view in [cell.contentView subviews])
{
if([view isKindOfClass:[UITextfield class]])
{
UITextField *textField = (UITextField *)view;
NSLog(#"%#",textField.text);
}
}
Why not have a datasource mapped to the TableView and just retrieve / update the values in the datasource. You can then call reloadRowsAtIndexPaths to load just the row you just changed. Trying to iterate through the TableView rather than just updating the datasource seems very inefficient.
Instead of UIView* subView = [[cell.contentView subviews]lastObject]; you can try to find it as:
for(UIView *view in [cell subviews])
{
if([view isKindOfClass:[UITextfield class]]){
// view is the reference to your textfield
}
}
That way you can add other UIViews as subviews and still get the reference of the textfield without having to keep track of its subview index.
2 things occur to me:
In the long run it'll be easier to create a UITableViewCell which contains a UITextField which is accessible as a property. You can either use a nib to layout the cell or do it programmatically in the cells init method. This approach will make your code easier to manage.
You need to consider cell reuse. If you are reusing cells (which you should be) then you will need store the fetch the value from the textfield before it is reused.

Strange bug in tableView

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.

UITextView inside UITableView

I know this question has been asked before, though I can't seem to find what I want. I have a section in my app where I have a tableview with a textview inside of it. I DO NOT want to have a seperate .xib, .h, and .m files for the tableview cell. The tableview does not need to shrink or grow depending on the amount of text inside the textview. I don't want the textview to be editable either. I hope this isn't too much to ask for, though I'm really stuck at the moment.
To do this, you will need to embed one in your UITableViewCell. But there's no need to create a custom cell. Here is the basic idea of what you will want to do:
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *CellIdentifier = #"Cell";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
UITextView *comment = [[UITextView alloc] initWithFrame:CGRectMake(cell.frame.origin.x, cell.frame.origin.y, cell.frame.size.width, tableView.rowHeight)];
comment.editable = NO;
comment.delegate = self;
[cell.contentView addSubview:comment];
[comment release];
}
return cell;
}
You will, of course, need to set your rowHeight if you don't want the standard 44pt height that comes with the cell. And if you want actual cells, you'll need to add your own logic so that only the cell you want is a textView, but this is the basic idea. The rest is yours to customize to your fitting. Hope this helps
EDIT: to bypass the textView to get to your cell, there are two ways to go about this.
1) you can make a custom textView class and overwrite touchesBegan to send the message to super:
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesBegan:touches withEvent:event];
}
this will send the touch events to its superview, which would be your tableView. Considering you didn't want to make custom UITableViewCells, I imagine you probably don't want to make a custom textView class either. Which leads me to option two.
2) when creating the textView, remove comment.editable = NO;. We need to keep it editable, but will fix that in a delegate method.
In your code, you will want to insert a textView delegate method and we'll do all our work from there:
EDIT: changing this code to use with a UITableViewController
- (BOOL)textViewShouldBeginEditing:(UITextView *)textView {
// this method is called every time you touch in the textView, provided it's editable;
NSIndexPath *indexPath = [self.tableView indexPathForCell:textView.superview.superview];
// i know that looks a bit obscure, but calling superview the first time finds the contentView of your cell;
// calling it the second time returns the cell it's held in, which we can retrieve an index path from;
// this is the edited part;
[self.tableView selectRowAtIndexPath:indexPath animated:NO scrollPosition:UITableViewScrollPositionNone];
// this programmatically selects the cell you've called behind the textView;
[self tableView:self.tableView didSelectRowAtIndexPath:indexPath];
// this selects the cell under the textView;
return NO; // specifies you don't want to edit the textView;
}
If that's not what you wanted, just let me know and we'll get you sorted out

Clear all UITextField changes in a UITableView with a UIButton

I have a UITableView with a dozen rows, each containing a UITextField.
By default the UITextField contains a placeholder value "Add Value" if the user hasn't previously edited the text field:
UITextField *textField = [[UITextField alloc] initWithFrame:CGRectMake(158, 6, 148, 24)];
NSString *strReplacement = [valueArray objectAtIndex:indexPath.row];
if (([strReplacement length] != 0) {
textField.text = strReplacement;
} else {
textField.placeholder = #"Add Value";
}
textField.delegate = self;
[cell addSubview:textField];
[textField release];
So far so good.
I've also added a UIButton to the footer of the UITableView.
What I want is to clear all the edited values and refresh all the UITextFields in the UITableView when the user clicks the UIButton.
I can easily enough remove all objects from the valueArray but I can't figure out how to refresh all the UITableView cells to reflect the changes.
Any help is appreciated.
lq
I believe what you're looking for is
[tableView reloadData];
Your solution feels weird. Filipe's right that the correct way to do it is with [wordsTableView reloadData], which will cause tableView:cellForRowAtIndexPath: to be called for each visible cell. That method is also called as you scroll through the table, so if reloadData isn't working, you're probably also going to end up with bugs with data not updating correctly as you change it and scroll. In your clearValues method, you're doing the same thing by calling tableView:cellForRowAtIndexPath:.
I think the real problem is in your tableView:cellForRowAtIndexPath: implementation. That method generally has 2 sections. First, you create or recycle a cell to get a reference with something like:
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier] autorelease];
}
Inside that if statement is generally the only place you should be adding subviews to your cell. If dequeueReusableCellWithIdentifier: returns a cell, it should already have the subview.
Then, after that if statement, you populate or update the contents of the subviews. The problem with your original code is that it's populating the text field and adding it as a subview, assuming there isn't already a text field in the cell. So your tableView:cellForRowAtIndexPath: should look something more like this:
int textFieldTag = 100;
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellIdentifier];
if (cell == nil) {
cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellIdentifier] autorelease];
UITextField *textField = [[UITextField alloc] initWithFrame:CGRectMake(158, 6, 148, 24)];
[textField setTag:textFieldTag];
[textField setDelegate:self];
[cell addSubview:textField];
[textField release];
}
UITextField *textField = [cell viewWithTag:textFieldTag];
NSString *strReplacement = [valueArray objectAtIndex:indexPath.row];
if (([strReplacement length] != 0) {
textField.text = strReplacement;
} else {
textField.placeholder = #"Add Value";
}
It looks like you may be setting the textField's tag value to the row number, presumably so you can use it in the UITextFieldDelegate. That could also lead to bugs, as if the cell from row 1 is recycled by dequeueReusableCellWithIdentifier: and becomes row 12, it's going to have an unexpected tag value. Even if it doesn't happen now, it's a bug waiting to happen, and will be tricky to troubleshoot.
Filipe's solution should also work, however, calling reloadData should be avoided wherever possible as calling this method has a high performance overhead.
You need some class that has a reference to both the UIButton instance as well as all the instances of the UITextField that you have on the screen/in the table. Sounds like the perfect job for your UITableView controller subclass!
In your code above, why don't you also add each UITextField that you create to an NSArray of text fields that lives in your UITableView controller? Then when the user presses the UIButton, the action can call some method in your controller class, which loops through all the UITextField elements in the NSArray setting the text property of each instance to #"".
Warning: If you're reusing cells then you may have to ensure that the controller's NSArray of UITextFields is being updated properly.
After a few hours of trial and error, I came up with this solution. The UIButton "Clear All" invokes the following method:
- (IBAction)clearValues:(id)sender {
// count the number of values in the array (this is the same as the number of rows in the table)
int count = [valueArray count];
// remove all values from the array (deletes any user added values):
[self.valueArray removeAllObjects];
UITableViewCell *cell;
UITextField *textField;
// loop through each row in the table and put nil in each UITextField:
for (NSUInteger i = 0; i < count; ++i) {
NSIndexPath *indexPath = [NSIndexPath indexPathForRow:i inSection:0];
cell = [self.wordsTableView cellForRowAtIndexPath:indexPath];
// NOTE: Make sure none of your tags are set to 0 since all non-tagged objects are zero.
// In table construction, your textFieldTags should be: textField.tag=indexPath.row+1;
textField = (UITextField*)[cell viewWithTag:i+1];
textField.text = nil;
}
}