Something 检查 UITableViewCell 中选定的行

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To set a checkmark:

UITableViewCell *cell = ...;
cell.accessoryType = UITableViewCellAccessoryCheckmark;

To select/deselect a cell:

[cell setSelected:TRUE animated:TRUE]; // select
[cell setSelected:FALSE animated:TRUE]; // deselect

To deselect the previous cell use a NSIndexPath *lastSelected ivar to track the last selected cell:

- (void)tableView:(UITableView*)tableView didSelectRowAtIndexPath:(NSIndexPath*)indexPath
{
if (self.lastSelected==indexPath) return; // nothing to do


// deselect old
UITableViewCell *old = [self.tableView cellForRowAtIndexPath:self.lastSelected];
old.accessoryType = UITableViewCellAccessoryNone;
[old setSelected:FALSE animated:TRUE];


// select new
UITableViewCell *cell = [self.tableView cellForRowAtIndexPath:indexPath];
cell.accessoryType = UITableViewCellAccessoryCheckmark;
[cell setSelected:TRUE animated:TRUE];


// keep track of the last selected cell
self.lastSelected = indexPath;
}

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In your UITableViewDatasource method:

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
static NSString *CellIdentifier = @"Cell";
UITableViewCell* cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];


if(cell == nil )
{
cell =[[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier] autorelease];
}
if ([indexPath compare:self.lastIndexPath] == NSOrderedSame)
{
cell.accessoryType = UITableViewCellAccessoryCheckmark;
}
else
{
cell.accessoryType = UITableViewCellAccessoryNone;
}
return cell;
}


// UITableView Delegate Method
-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
self.lastIndexPath = indexPath;


[tableView reloadData];
}

And lastIndexPath is a property(strong) NSIndexPath* lastIndexPath;

小开

small typo

// deselect old
UITableViewCell *old = [self.tableView cellForRowAtIndexPath:self.lastSelected];
cell.accessoryType = UITableViewCellAccessoryNone;
[cell setSelected:FALSE animated:TRUE];

should read

// deselect old
UITableViewCell *old = [self.tableView cellForRowAtIndexPath:self.lastSelected];
old.accessoryType = UITableViewCellAccessoryNone;
[old setSelected:FALSE animated:TRUE];

and also in the

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
if (indexPath.row == [previouslySelected intValue])
{
cell.accessoryType = UITableViewCellAccessoryCheckmark;
selectedIndex = indexPath;
[cell setSelected:YES animated:YES];
}
else
{
cell.accessoryType = UITableViewCellAccessoryNone;
[cell setSelected:NO animated:YES];
}
}

where previouslySelected is your local ivar, etc. that way if you reload with a selected index it also gets deselected when you flick through the possible selections.

小开

最佳答案

Do not use [tableview reloadData]; // its a hammer.

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath   *)indexPath
{
[tableView cellForRowAtIndexPath:indexPath].accessoryType = UITableViewCellAccessoryCheckmark;
}


-(void)tableView:(UITableView *)tableView didDeselectRowAtIndexPath:(NSIndexPath *)indexPath
{
[tableView cellForRowAtIndexPath:indexPath].accessoryType = UITableViewCellAccessoryNone;
}

小开

I found that reloading the data interrupts the deselect animation in an ugly way.

This Swift implementation cleanly adds/removes checkmarks and deselects the row:

func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
if self.lastSelection != nil {
self.myTableView.cellForRowAtIndexPath(self.lastSelection)?.accessoryType = .None
}


self.myTableView.cellForRowAtIndexPath(indexPath)?.accessoryType = .Checkmark


self.lastSelection = indexPath


self.myTableView.deselectRowAtIndexPath(indexPath, animated: true)
}

where lastSelection is declared as var lastSelection: NSIndexPath!

No extra activity in cellForRowAtIndexPath needed. Shouldn't be hard to replicate in Obj-C.

小开

The upper mentioned code only works with the single selection.This following code will surely works for multiple selections.

- (void)viewDidLoad {
arrSelectionStatus =[NSMutableArray array]; //arrSelectionStatus holds the cell selection status
for (int i=0; i<arrElements.count; i++) { //arrElements holds those elements which will be populated in tableview
[arrSelectionStatus addObject:[NSNumber numberWithBool:NO]];
}
}


-(UITableViewCell*)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath{


UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"Cell"];


if (cell==nil) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"Cell"];
}


cell.textLabel.text=[arrElements objectAtIndex:indexPath.row];


if ([[arrSelectionStatus objectAtIndex:indexPath.row] boolValue] == YES)
cell.accessoryType = UITableViewCellAccessoryCheckmark;
else
cell.accessoryType = UITableViewCellAccessoryNone;


return cell;
}


-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath{


UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
cell.accessoryType = UITableViewCellAccessoryCheckmark;


[arrSelectionStatus replaceObjectAtIndex:indexPath.row withObject:[NSNumber numberWithBool:YES]];
}


-(void)tableView:(UITableView *)tableView didDeselectRowAtIndexPath:(NSIndexPath *)indexPath{
UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
cell.accessoryType = UITableViewCellAccessoryNone;


[arrSelectionStatus replaceObjectAtIndex:indexPath.row withObject:[NSNumber numberWithBool:NO]];
}

小开

Assuming you are in a class that inherits from UITableViewController, this does the trick in Swift 3:

override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
// Add a visual cue to indicate that the cell was selected.
self.tableView.cellForRow(at: indexPath)?.accessoryType = .checkmark
}


override func tableView(_ tableView: UITableView, willSelectRowAt indexPath: IndexPath) -> IndexPath? {
// Invoked so we can prepare for a change in selection.
// Remove previous selection, if any.
if let selectedIndex = self.tableView.indexPathForSelectedRow {
// Note: Programmatically deslecting does NOT invoke tableView(:didSelectRowAt:), so no risk of infinite loop.
self.tableView.deselectRow(at: selectedIndex, animated: false)
// Remove the visual selection indication.
self.tableView.cellForRow(at: selectedIndex)?.accessoryType = .none
}
return indexPath
}

小开

Just Call didSelectRowAtIndexPath Method when select any row to Show CheckMark and Select checkmark row for hide CheckMark.

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath: (NSIndexPath *)indexPath {
[tableView deselectRowAtIndexPath:indexPath animated:true];
NSLog(@"touch");


UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
if (cell.accessoryType == UITableViewCellAccessoryNone)
{
cell.accessoryType = UITableViewCellAccessoryCheckmark;
}
else
{
cell.accessoryType = UITableViewCellAccessoryNone;
}
}

小开

When a selected cell(with the check mark is selected again), just remove the selection.

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath*)indexPath
{
BOOL isSelected = ([tableView cellForRowAtIndexPath:indexPath].accessoryType ==  UITableViewCellAccessoryCheckmark);
if(isSelected){
[tableView cellForRowAtIndexPath:indexPath].accessoryType = UITableViewCellAccessoryNone;
[tableView deselectRowAtIndexPath:indexPath animated:YES]; //this won't trigger the didDeselectRowAtIndexPath, but it's always a good idea to remove the selection
}else{
[tableView cellForRowAtIndexPath:indexPath].accessoryType = UITableViewCellAccessoryCheckmark;
}
}


- (void)tableView:(UITableView *)tableView didDeselectRowAtIndexPath:(NSIndexPath*)indexPath
{
[tableView cellForRowAtIndexPath:indexPath].accessoryType = UITableViewCellAccessoryNone;
}

Bonus:

Use self.tableView.indexPathForSelectedRow for detecting indexPath for the selected cell

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The above answers not work if you reused the cell for large number of data. On scroll you can see repeated checkmark. To avoid use below steps:

declare on variable : var indexNumber:NSInteger = -1

Add below code in cellforRowAtIndexPath:

 override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell{
if indexNumber == indexPath.row{
cell.accessoryType = .checkmark
}else{
cell.accessoryType = .none
}
}

And in didselectAtIndexpath add below code:

override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {

override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
tableView.cellForRow(at: indexPath as IndexPath)?.accessoryType = .checkmark
indexNumber = indexPath.row
}
override func tableView(_ tableView: UITableView, didDeselectRowAt indexPath: IndexPath) {
tableView.cellForRow(at: indexPath as IndexPath)?.accessoryType = .none
}

小开

It's better to face this problem from other direction. Put all work on internal UIKit mechanisms and move implementation to UITableViewCell:

@implementation MYTableViewCell


- (void)setSelected:(BOOL)selected animated:(BOOL)animated {
[super setSelected:selected animated:animated];


self.accessoryType = selected ? UITableViewCellAccessoryCheckmark : UITableViewCellAccessoryNone;
}


- (void)prepareForReuse {
[super prepareForReuse];
self.accessoryType = UITableViewCellAccessoryNone;
}


@end

小开

extension ViewController : UITableViewDelegate,UITableViewDataSource {


func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return self.dataArray.count
}


func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath)
cell.textLabel?.text = dataArray[indexPath.row]
if selectedData.contains(dataArray[indexPath.row]) {
cell.accessoryType = .checkmark
}else{
cell.accessoryType = .none
}
return cell
}




func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {


if selectedData.contains(dataArray[indexPath.row]) {
selectedData.removeLast()
tableView.cellForRow(at: indexPath)?.accessoryType = .none
}else {
selectedData.removeAll()
selectedData.append(dataArray[indexPath.row])
tableView.cellForRow(at: indexPath)?.accessoryType = .checkmark
}
print(selectedData)
}


func tableView(_ tableView: UITableView, didDeselectRowAt indexPath: IndexPath) {
tableView.cellForRow(at: indexPath)?.accessoryType = .none
}


}

based on dataArray table view formed.. similarly, I took an empty array, and whenever the user taps on a cell, based on indexValue of from dataArray I stored that object in selectedDataArray

As for the question its like... A question has multiple options(Answers), But at finally only one or none answer will be a result

Likewise, only one cell should show checkmark and remaining cells should be in unselected... it some case u can deselect your answer... I hope this is the best answer to this question

小开

Update Swift 4

  func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
tableView.cellForRow(at: indexPath)?.accessoryType = .checkmark
}


func tableView(_ tableView: UITableView, didDeselectRowAt indexPath: IndexPath) {
tableView.cellForRow(at: indexPath)?.accessoryType = .none
}

小开

swift 4 in case you need.

var lastSelection: NSIndexPath!
override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {




//CHECK MARK THE CELL
if self.lastSelection != nil {
self.tableView.cellForRow(at: self.lastSelection as IndexPath)?.accessoryType = .none
}


self.tableView.cellForRow(at: indexPath)?.accessoryType = .checkmark


self.lastSelection = indexPath as NSIndexPath


self.tableView.deselectRow(at: indexPath, animated: true)


}

小开

Using Swift 4.2 and swift 5 Working code of check mark for only selected row in TableView

   func tableView(_ tableView: UITableView, didDeselectRowAt indexPath: IndexPath) {
self.tableView.cellForRow(at: indexPath)?.accessoryType = .none
}
func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
//print(self.coloursArray[indexPath.row])


self.tableView.cellForRow(at: indexPath)?.accessoryType = .checkmark
}

小开

I think it's cleaner to set the accessory within your custom UITableViewCell implementation. In swift, I have used:

override func setSelected(_ selected: Bool, animated: Bool) {
super.setSelected(selected, animated: animated)


// Configure the view for the selected state
accessoryType = selected ? .checkmark : .none
}

小开

There are two ways you could do it. one is without multiple selections and another is with multiple selections.

// Table View Controller -- without Multiple Selection


// Step 1


override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {


if(tableView.cellForRow(at: indexPath)?.imageView?.image == UIImage(systemName:"checkmark.circle")) {
tableView.cellForRow(at: indexPath)?.imageView?.image = UIImage(systemName:"circle")
} else {
tableView.cellForRow(at: indexPath)?.imageView?.image = UIImage(systemName:"checkmark.circle")
}
}


//Step 2


override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {


let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
cell.textLabel?.text = employeeValues[indexPath.row]
cell.imageView?.image = UIImage(systemName:"circle")


return cell
}


//  Table View Controller -- with Multiple Selection


@IBOutlet var myTableView: UITableView!


override func viewDidLoad() {
super.viewDidLoad()
self.myTableView.allowsMultipleSelection = true
}


override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {


let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath)
cell.textLabel?.text = employeeValues[indexPath.row]
cell.imageView?.image = UIImage(systemName:"circle")


return cell
}


override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {


//   let cell = tableView.cellForRow(at: indexPath)?.accessoryType = UITableViewCell.AccessoryType.checkmark


tableView.cellForRow(at: indexPath)?.imageView?.image = UIImage(systemName:"checkmark.circle")


}


override func tableView(_ tableView: UITableView, didDeselectRowAt indexPath: IndexPath) {


tableView.cellForRow(at: indexPath)?.imageView?.image = UIImage(systemName:"circle")
}

小开

// Check or Uncheck a cell
if let cell = tableView.cellForRow(at: indexPath) {
if cell.accessoryType == .checkmark {
cell.accessoryType = .none
} else {
cell.accessoryType = .checkmark
}
}

小开

Swift 5

    var selectedIndex: IndexPath!


func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
if selectedIndex != nil {
tableView.cellForRow(at: selectedIndex)?.accessoryType = .none
}
tableView.cellForRow(at: indexPath)?.accessoryType = .checkmark
selectedIndex = indexPath
tableView.deselectRow(at: indexPath, animated: true)
}