我想知道如何设置我的UICollectionView
,以便每个部分最多可以选择1个单元格。我看到UICollectionView有allowsMultipleSelection
属性,但我想知道如何防止在同一部分中选择多个单元格。
我是否需要在– collectionView:shouldSelectItemAtIndexPath:
和collectionView:shouldDeselectItemAtIndexPath:
方法中实现逻辑,还是有更简单的方法?
谢谢!
答案 0 :(得分:9)
在didSelectRowAtIndexPath中你可以这样做:
- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
NSArray * selectedRows = self.tableView.indexPathsForSelectedRows;
for (NSIndexPath * selectedRow in selectedRows) {
if ((selectedRow.section == indexPath.section) && (selectedRow.row != indexPath.row)) {
[self.tableView deselectRowAtIndexPath:selectedRow animated:NO];
}
}
}
allowsMultipleSelection应设置为YES。
希望它有所帮助!
答案 1 :(得分:0)
您可能需要在-shouldSelect
和-shouldDeselect
中执行逻辑操作。也许保留每个部分选择的单元格数量字典?
NSMutableDictionary *dict;
- (BOOL)collectionView:(UICollectionView *)view shouldSelectItemAtIndexPath:(NSIndexPath *)path
{
NSInteger *section = path.section;
if (!dict)
{
dict = [[NSMutableDictionary alloc] init];
}
NSNumber *numberSelected = [dict objectForKey:[NSNumber numberWithInteger:section]];
if (numberSelected > 0)
{
return NO;
}
else
{
[dict setObject:[NSNumber numberWithDouble:numberSelected.doubleValue - 1] forKey:[NSNumber numberWithInteger:section]];
return YES;
}
}
- (BOOL)collectionView:(UICollectionView *)view shouldDeselectItemAtIndexPath:(NSIndexPath *)path
{
NSInteger *section = path.section;
if (!dict)
{
dict = [[NSMutableDictionary alloc] init];
}
NSNumber *numberSelected = [dict objectForKey:[NSNumber numberWithInteger:section]];
numberSelected = [NSNumber numberWithDouble:numberSelected.doubleValue - 1];
[dict setObject:numberSelected forKey:[NSNumber numberWithInteger:section]];
return YES;
}
这应该有效。
答案 2 :(得分:0)
在Swift 2.0中:
import re
if re.search("world \d", line):
...
答案 3 :(得分:0)
在Swift 5.0中:
override func viewDidLoad() {
super.viewDidLoad()
self.collectionView.allowsMultipleSelection = true
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
(collectionView.indexPathsForSelectedItems ?? [])
.filter { $0.section == indexPath.section && $0.item != indexPath.item && $0.row != indexPath.row }
.forEach { self.collectionView.deselectItem(at: $0, animated: false) }
}
如果您希望它在本节的各个项目之间切换,请使用以下方法:
override func viewDidLoad() {
super.viewDidLoad()
self.collectionView.allowsMultipleSelection = true
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
(collectionView.indexPathsForSelectedItems ?? [])
.filter { $0.section == indexPath.section && $0.item }
.forEach { self.collectionView.deselectItem(at: $0, animated: false) }
}
我认为这可以带来更好的用户体验,但这是您的电话