I have a tableView in which i post users feeds and i added a heart button for like in the cell view. I created a class for the cell view and declared my #IBOutlet of the button there. Then in the cellForRowAtIndexPath in the tableview i called the button and made the indexpath.row the tag number of the button itself. Then i added a target with an action to be done and created my #IBAction. Now I'm trying to change the image look of the heart button to red but nothing happens. Is there a problem passing the an UIImage to the button via the sender. I have no errors. And the if like = statement is working correctly. Here is my code:
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as! PostsCellTableViewCell
cell.heartButton.tag = indexPath.row
cell.heartButton.addTarget(self, action: "liked:", forControlEvents: .TouchUpInside)
return cell
}
#IBAction func liked (sender: UIButton){
if like == false{
sender.imageView?.image = UIImage(contentsOfFile: "red-heart.png")
like = true
}
else{
sender.imageView?.image = UIImage(contentsOfFile: "white-heart-hi.png")
like = false
}
// self.tableView.reloadData()
}
Try this instead.
if like == false{
sender.setImage(UIImage(named: "red-heart.png"), forState: .Normal)
like = true
} else {
sender.setImage.setImage(UIImage(named: "white-heart-hi.png"), forState: .Normal)
like = false
}
This is a really simple error. You declared your target function as "liked:", but your function is declared as "liked". Notice the lack of a colon the second time. This is critical, and should fix the problem. If this does not fix the problem, make sure you have declared
var like = false
If this still doesn't work, comment and I will continue helping. If it does work, don't forget to check my answer.
Related
I am trying to implement play/pause button in tableview cell. each cell having single button, whenever user click it, It should change button image also need to call required function, also after scroll it should same.
Below code I am using
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) - > UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("productCell") as ? SepetCell
cell.onButtonTapped = {
//Do whatever you want to do when the button is tapped here
}
See first of all every button of the tableView Cell will have a unique tag associated with it, so in order to update the button of a particular cell, you will have to define the tag of a button in the cells and then pass this tag to your function to perform action on that particular button of the selected cell.
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell
{
let cell = tableView.dequeueReusableCell(withIdentifier: "cell_identifier", for:
indexPath) as! CellClass
cell.button.tag = indexPath.row
cell.button.addTarget(self, action: #selector(playpause), for: .touchUpInside)
}
#objc func playpause(btn : UIButton){
if btn.currentImage == UIImage(named: "Play") {
btn.setImage(UIImage(named : "Pause"), forState: .Normal)
}
else {
btn.setImage(UIImage(named : "Play"), forState: .Normal)
}
// perform your desired action of the button over here
}
State of the art in Swift are callback closures. They are easy to implement and very efficient.
In the data source model add a property
var isPlaying = false
In Interface Builder select the button in the custom cell and press ⌥⌘4 to go to the Attributes Inspector. In the popup menu State Config select Default and choose the appropriate image from Image popup, Do the same for the Selected state.
In the custom cell add a callback property and an outlet and action for the button (connect both to the button). The image is set via the isSelected property.
#IBOutlet weak var button : UIButton!
var callback : (()->())?
#IBAction func push(_ sender: UIButton) {
callback?()
}
In the controller in cellForRow add the callback, item is the current item of the data source array. The state of the button is kept in isPlaying
cell.button.isSelected = item.isPlaying
cell.callback = {
item.isPlaying = !item.isPlaying
cell.button.isSelected = item.isPlaying
}
I'm trying to add the download button for some items in my tableView. I've created the custom cell class and added the label and the button outlets, everything is working in displaying the info and even the buttons are showing where it should be.
I'm trying to add the target, but it does nothing. I need to pass the row index to the buttonClicked function or should I create this function in the custom cell class and then do the action some how? I would like to know the best practise of this.
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "PlaylistCell", for: indexPath) as! PlaylistTableViewCell
let playlist = self.playlists?[indexPath.row]
cell.titleLabel.text = playlist?.getTitle()
if (playlist?.isOfflineAvailable())! {
cell.downloadButton.isHidden = false
} else {
cell.downloadButton.isHidden = true
cell.downloadButton.tag = indexPath.row
cell.downloadButton.addTarget(self, action: #selector(buttonClicked(sender:)), for: .touchUpInside)
}
return cell
}
func buttonClicked(sender: UIButton) {
let buttonRow = sender.tag
print(buttonRow)
}
I've also tried removing the (sender:) from #selector, but it does not change a functionality.
In order to handle button callback in your view controller, you have two choices:
Target-action:
Add target-action in cellForRow method just as you did. Your code is probably not working because you are hiding the button when it should be visible, aren't you?
I guess you need to replace this
if (playlist?.isOfflineAvailable())! {
cell.downloadButton.isHidden = false
} else {
cell.downloadButton.isHidden = true
cell.downloadButton.tag = indexPath.row
cell.downloadButton.addTarget(self, action: #selector(buttonClicked(sender:)), for: .touchUpInside)
}
With this:
cell.downloadButton.isHidden = playlist?.isOfflineAvailable()
cell.downloadButton.tag = indexPath.row
cell.downloadButton.addTarget(self, action: #selector(buttonClicked(sender:)), for: .touchUpInside)
You should update tag every time because cell are reused in tableView and if don't do it every time when cellForRow is called, you may easilly get a case when a callback is called but it's tag belongs to indexPath from the previous cell usage. Also I've changed isHidden logics to the opposite. I guess you should hide the button when isOfflineAvailable returns true, right?
Delegate pattern
It is described a million of times here on SO and on many other sites as well. Basically you define a cell protocol, implement it in your controller and send callbacks from cell to it's delegate whenever a button is pressed. You can find more details in my answer for a similar question.
I have a problem about my cell's button.
In my tableView each row is composed by: an image, some labels and a button.
The button has a checkmark image. When it is clicked, the button's image changes.
The problem is that also another button's image changes without reason.
This mistake happens because my cell is reused.
I have tried to use prepareForReuse method in TableViewCell but nothing happens. I've also tried with selectedRowAt but I didn't have any results. Please help me.
Image 1:
Image 2:
This is my func in my custom Cell:
override func prepareForReuse() {
if checkStr == "uncheck"{
self.checkBook.setImage(uncheck, for: .normal)
} else if checkStr == "check"{
self.checkBook.setImage(check, for: .normal)
}
}
func isPressed(){
let uncheck = UIImage(named:"uncheck")
let check = UIImage(named: "check")
if self.checkBook.currentImage == uncheck{
checkStr == "check"
} else self.checkBook.currentImage == check{
checkStr == "uncheck"
}
}
In my tableView:
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
let selectedCell: ListPropertyUserCell = tableView.cellForRow(at: indexPath) as! ListPropertyUserCell
let uncheck = UIImage(named:"uncheck")
let check = UIImage(named: "check")
if selectedCell.checkBook.imageView?.image == uncheck{
selectedCell.checkStr = "check"
} else if selectedCell.checkBook.imageView?.image == check{
selectedCell.checkStr = "uncheck"
}
}
From the information in your post, this looks like a cell reuse issue. The problem is that the tableView reuses the cells rather than creating new ones, to maintain performance. If you haven't reset the cell's state, the reused cell will be remain configured in the old state.
For a quick fix, you can implement the prepareForReuse method on UITableViewCell.
However, you'll need to store which cell is 'checked' in your view controller if you want the checkbox to be selected after scrolling the tableView. You can store this yourself, or use the tableView's didSelectRowAtIndexPath method.
Try to do it like this:
var checkBook = UIImageView()
if self.checkBook.image == UIImage(named: "check"){
self.checkBook.image = UIImage(named: "uncheck")
}
else{
self.checkBook.image = UIImage(named: "check")
}
If you're using the click on the entire cell, you can override the setSelected func in your custom cell just like that.
override func setSelected(selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)
if selected {
self.checkBook.image = UIImage(named: "check")
} else {
self.checkBook.image = UIImage(named: "uncheck")
}
}
UITableViewCell is reusable. You can't store state of view in cell. You should setup cell in
func tableView(UITableView, cellForRowAt: IndexPath)
method of your data source
The easiest way to achieve that is to implement
func tableView(UITableView, didSelectRowAt: IndexPath)
func tableView(UITableView, didDeselectRowAt: IndexPath)
methods of UITableViewDelegate
Then you can add/remove indexPath to some array in these methods and in cellForRowAtIndexPath setup cell.
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("YourTableViewCell") as! YourTableViewCell
if array.contains(indexPath) {
cell.checkBook.image = UIImage(named: "check")
} else {
cell.checkBook.image = UIImage(named: "uncheck")
}
return cell
}
Try my code . here selectindex is use for get selected cell index and selectedindex is NSMutableArray that i store all selected cell value.
var selectindex : Int?
var selectedindex : NSMutableArray = NSMutableArray()
#IBOutlet var tableview: UITableView!
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("LikeCell", forIndexPath: indexPath)
let like: UIButton = (cell.viewWithTag(2) as! UIButton)// like button
let comment: UIButton = (cell.viewWithTag(3) as! UIButton) // comment button
comment.setBackgroundImage(UIImage(named: "chat.png"), forState: UIControlState.Normal) // comment button set
like.addTarget(self, action: #selector(self.CloseMethod(_:event:)), forControlEvents: .TouchDown)
comment.addTarget(self, action: #selector(self.CloseMethod1(_:event:)), forControlEvents: .TouchDown)
return cell
}
// This is my like button action method.
#IBAction func CloseMethod(sender: UIButton, event: AnyObject) {
let touches = event.allTouches()!
let touch = touches.first!
let currentTouchPosition = touch.locationInView(self.tableview)
let indexPath = self.tableview.indexPathForRowAtPoint(currentTouchPosition)!
selectindex = indexPath.row
if selectedindex.containsObject(selectindex!) {
sender.setBackgroundImage(UIImage.init(named: "like (1).png"), forState: .Normal)
selectedindex.removeObject(selectindex!)
}else{
sender.setBackgroundImage(UIImage.init(named: "like.png"), forState: .Normal)
selectedindex.addObject(selectindex!)
}
}
I faced this problem recently, and did not find much about it. What solve, after much searching, was to use:
override func prepareForReuse() {
btnAdd.setImage(nil, for: .normal) //here I use to change to none image
super.prepareForReuse()
}
just put this method inside your custom UITableViewCell, and set which item you want to realese stats.
I have a collection view and inside a button.
When I tap this button I want to change its name.
I managed to do it but when I tap it, it changes if I have 20 buttons 10 of them like this if I tap the first button it changes the 0,2,4,6,8 and if I tap a button which isn't in the list then all buttons are checked.
This is my code:
#IBAction func following(sender: AnyObject) {
if follow.tag == sender.tag {
follow.setTitle("Following", forState: .Normal)
}
print("\(follow.tag) \(sender.tag)")
}
func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
let cell = collectionView.dequeueReusableCellWithReuseIdentifier("Interest Cell", forIndexPath: indexPath) as! ThirdTabCell
cell.follow.tag = indexPath.row
return cell
}
Inside button's function I tried without if statement too but again the same problem.
When I print the tags it prints only the button which was tapped.
I also tried this to my ViewController
cell.follow.addTarget(self, action: #selector(ThirdTab.follow(_:)), forControlEvents: UIControlEvents.TouchUpInside)
//inside cellForItemAtIndexPath
func follow(sender:UIButton!) {
}
Just a short overview, So you get your answer
UICollectionView is highly optimized, and thus only keep On-screen visible rows in memory. Now, All rows Cells are cached in Pool and are reused and not regenerated. Whenever, user scrolls the UICollectionView, it adds the just-hidden rows in Pool and reuses them for next to be visible rows.
So, now, coming to your answer
When you tap on button, its title will get updated, but when you will scroll your collection view, the same cell with "updated button text" will be reused and that will cause the issue you are seeing.
SOLUTION
SAVE button state in an array, in your action method
#IBAction func following(sender: AnyObject) {
if follow.tag == sender.tag {
array[sender.tag] = "<text>"
collectionView.reloadData()
}
print("\(follow.tag) \(sender.tag)")
}
and inside your datasource method
update your button text like below:
//trick is to update your button text for each index
func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell{
//SAMPLE CODE
let buttonValue = array[indexPath.index]
// update button value for each index
//trick is to update your button text for each index
cell.button.setTitle("", forState: .Normal)
}
Please change below the set title line in following function.
Existing Line:
follow.setTitle("Following", forState: .Normal)
New Line:
follow.setTitle("Following", forState: UIControlState.Normal)
Hope this is working for you.
Thanks
I would suggest you to approach it this way.
Inside cellForItemAtIndexPath you can assign a buttons outlet like this
cell.followOutlet.tag = indexPath.row
and then inside your follow function you can do this
#IBAction func following(sender: AnyObject) {
let follow = sender as! UIButton
let indexP = NSIndexPath(forRow: follow.tag, inSection: 0)
let cell = yourCollectionView.cellForItemAtIndexPath(indexP) as! yourCellName
follow.setTitle("Following", forState: .Normal)
}
And now you can do whatever you want with your button.
I'm using a custom TableViewCell in my iOS app. I use the method tableViewDidSelectRowAtIndexPath to open a new ViewController. What I need to do is to add a button or an image somewhere in the custom cell so if I tap the button or whatever element don't open the ViewController, but execute a function without opening the cell.
set [cell.button setTag:indexPath.row] in cellForRowAtIndexPath method.
and than addTarget to cell.button like
[cell.button addTarget:self action:#selector(yourAction:) forControlEvents:UIControlEventTouchUpInside]];
and than do Whatever you want to do in yourAction
with getting tag from sender.
Or you want code for that than please add your code what you had done so we can help more if you are new in iOS.
This code may helps you
here i have used custom buttom in table and add target to that buton
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell
{
let cell: AnyObject = tableView.dequeueReusableCellWithIdentifier("CellIdentifier", forIndexPath: indexPath)
// use your custom cell here
//cell = UIColor.redColor()
//cell.textLabel?!.text = String(data[indexPath.row])
//nameTextField.text = ""
let custom_btn : UIButton? = UIButton.init(type: .System)
//declaring custom button
custom_btn?.setTitle("custom button", forState: .Normal)
custom_btn!.tag = indexPath.row
custom_btn!.addTarget(self, action: "buttonClicked:", forControlEvents: UIControlEvents.TouchUpInside)
cell .addSubview(custom_btn!);
return cell as! UITableViewCell
}
func buttonClicked(sender:UIButton)
{
if(sender.tag == 5){
//Do something for tag
}
print("hello")
}