Simple way to show the 'Copy' popup on UITableViewCells like the address book App

问题

Is there a simple way for subclasses of UITableViewCell to show the 'Copy' UIMenuController popup like in the Address book app (see screenshot), after the selection is held for a while?

回答1:

The method before iOS 5 is to get the UIMenuController's shared instance, set the target rect and view and call -setMenuVisible:animated:. Remeber to implement -canPerformAction:withSender: in your responder.

The method after iOS 5 (previously available as undocumented feature) is to implement these 3 methods in your data source (see https://developer.apple.com/reference/uikit/uitableviewdelegate#1653389).

-(void)tableView:(UITableView*)tableView performAction:(SEL)action forRowAtIndexPath:(NSIndexPath*)indexPath withSender:(id)sender;
-(BOOL)tableView:(UITableView*)tableView canPerformAction:(SEL)action forRowAtIndexPath:(NSIndexPath*)indexPath withSender:(id)sender;
-(BOOL)tableView:(UITableView*)tableView shouldShowMenuForRowAtIndexPath:(NSIndexPath*)indexPath;

回答2:

There is now official interface for displaying UITableView cell menus in iOS 5. Example (from the table delegate):

- (BOOL)tableView:(UITableView *)tableView shouldShowMenuForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return YES;
}

- (BOOL)tableView:(UITableView *)tableView canPerformAction:(SEL)action forRowAtIndexPath:(NSIndexPath *)indexPath withSender:(id)sender
{
    return (action == @selector(copy:));
}

- (void)tableView:(UITableView *)tableView performAction:(SEL)action forRowAtIndexPath:(NSIndexPath *)indexPath withSender:(id)sender
{
    if (action == @selector(copy:)){
        UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
        [[UIPasteboard generalPasteboard] setString:cell.textLabel.text];
    }
}

I tried modifying the UIMenuController's shared controller to add my own menu item, and I was able to add it and get the canPerformAction message for it, but returning YES didn't help; I wasn't able to make my custom menu item appear. From my experiments, it looks like only Copy, Cut, and Paste are supported. [EDIT Since this was posted, I've learned how to add custom menu items.]

Note that this works only if all three delegate methods are implemented.

回答3:

Here is the Swift syntax for copying detailTextLabel.

func tableView(_ tableView: UITableView, shouldShowMenuForRowAt indexPath: IndexPath) -> Bool {
    return (tableView.cellForRow(at: indexPath)?.detailTextLabel?.text) != nil
}

func tableView(_ tableView: UITableView, canPerformAction action: Selector, forRowAt indexPath: IndexPath, withSender sender: Any?) -> Bool {
    return action == #selector(copy(_:))
}

func tableView(_ tableView: UITableView, performAction action: Selector, forRowAt indexPath: IndexPath, withSender sender: Any?) {
    if action == #selector(copy(_:)) {
        let cell = tableView.cellForRow(at: indexPath)
        let pasteboard = UIPasteboard.general
        pasteboard.string = cell?.detailTextLabel?.text
    }
}

回答4:

Your UITableViewCell subclass may look like this

@interface MenuTableViewCell : UITableViewCell {
}
- (IBAction)copy:(id)sender;
- (void)showMenu;

@end


@implementation MenuTableViewCell

- (BOOL)canBecomeFirstResponder {
    return YES;
}
- (BOOL)canPerformAction:(SEL)action withSender:(id)sender
{
    if (action == @selector(copy:)) {
        return YES;
    }
    return NO;
}
- (IBAction)copy:(id)sender {
}
- (void)showMenu {
    [[UIMenuController sharedMenuController] setMenuVisible:NO animated:YES];
    [self becomeFirstResponder];
    [[UIMenuController sharedMenuController] update];
    [[UIMenuController sharedMenuController] setTargetRect:CGRectZero inView:self];
    [[UIMenuController sharedMenuController] setMenuVisible:YES animated:YES];

}

@end

And the UITableView delegate methods are like

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

    static NSString *CellIdentifier = @"Cell";

    MenuTableViewCell *cell = (MenuTableViewCell *)[tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[[MenuTableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];
    }

    // Configure the cell.
    return cell;
}

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    MenuTableViewCell *cell = (MenuTableViewCell *)[tableView cellForRowAtIndexPath:indexPath];
    [cell showMenu];
}

回答5:

 #pragma mark - COPY/PASTE Cell Text via Menu

- (BOOL)tableView:(UITableView *)tableView shouldShowMenuForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return YES;
}

- (BOOL)tableView:(UITableView *)tableView canPerformAction:(SEL)action forRowAtIndexPath:(NSIndexPath *)indexPath withSender:(id)sender
{
    return (action == @selector(copy:));
}

- (void)tableView:(UITableView *)tableView performAction:(SEL)action forRowAtIndexPath:(NSIndexPath *)indexPath withSender:(id)sender
{
    if (action == @selector(copy:))
    {
        UITableViewCell *cell = [tableView cellForRowAtIndexPath:indexPath];
        UIPasteboard *pasteBoard = [UIPasteboard generalPasteboard];
        [pasteBoard setString:cell.textLabel.text];
    }
}

回答6:

For pre iOS13, refer to Alexander's answer. For iOS13 shouldShowMenuForRowAt and canPerformAction are deprecated, hence you have to do use the following API:

@available(iOS 13.0, *)
override func tableView(_ tableView: UITableView, contextMenuConfigurationForRowAt indexPath: IndexPath, point: CGPoint) -> UIContextMenuConfiguration? {

    return UIContextMenuConfiguration(identifier: nil, previewProvider: nil, actionProvider: { suggestedActions in

        return self.makeContextMenu(for: indexPath)
    })
}

@available(iOS 13.0, *)
func makeContextMenu(for indexPath: IndexPath) -> UIMenu {

    let copyAction = UIAction(title: "Copy") { [weak self] _ in
        guard let self = self else { return }
        let cell = self.tableView.cellForRow(at: indexPath)
        let pasteboard = UIPasteboard.general
        pasteboard.string = cell?.detailTextLabel?.text

    }

    // Create and return a UIMenu with the share action
    return UIMenu(title: "Options", children: [copyAction])
}

Note: The end result will be different. But this is out of the box functionality that Apple is providing. However checking the Settings app on iOS 13 Sim >> General >> About. long-pressing a cell will not have the UI below, it will be the old UI, which is a bit inconsistent.

来源：https://stackoverflow.com/questions/2487844/simple-way-to-show-the-copy-popup-on-uitableviewcells-like-the-address-book-ap

标签

ios

objective-c

iphone

uitableview

pasteboard