Question

我想从左侧向左滑动时删除所有选定的单元格。

我的.m文件

- (IBAction)handleSwipeLeft:(UISwipeGestureRecognizer *)sender{

    CGPoint location = [_gestureSwipeLeft locationInView:_tblThingsToDo];
    NSIndexPath *swipedIndexPath = [_tblThingsToDo indexPathForRowAtPoint:location];
    UITableViewCell *swipedCell  = [_tblThingsToDo cellForRowAtIndexPath:swipedIndexPath];

    if (swipedCell.selected == NO) {
        swipedCell.selected = YES;
    }
    else{
    swipedCell.selected = NO;
    }
}


-(void)deleteCurrentobject:(id)sender{
    if(self.selectedCells){
        [_things removeObjectAtIndex:_indexPath.row];
        [self.tblThingsToDo deleteRowsAtIndexPaths:[NSArray arrayWithObject:_indexPath] withRowAnimation:UITableViewRowAnimationFade];
    }
}

我希望在按下调用deleteCurrentObject方法的按钮时删除所有swipedCell.selected。我该怎么做？

Answer 1

将下面的内容放在swipedCell类的init方法中，否则刷新对象创建时间。

[self addObserver: swipedCell forKeyPath:@"selected" options:NSKeyValueObservingOptionNew context:NULL];

当您调用handleSwipeLeft:方法时，它会自动调用以下方法，

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context{
     if ([keyPath isEqualToString:@"selected"] && [object isKindOfClass:[UITableViewCell class]]) {
       if(object.selected){
       [_things removeObjectAtIndex:_indexPath.row];
         [self.tblThingsToDo beginUpdates];
         [self.tblThingsToDo deleteRowsAtIndexPaths:[NSArray arrayWithObject:_indexPath] withRowAnimation:UITableViewRowAnimationFade];
         [self.tblThingsToDo endUpdates];
      }
    }
}

删除观察者使用下面的代码

[self removeObserver:swipedCell forKeyPath:@"selected"];

Answer 2

试试这个，

- (IBAction)handleSwipeLeft:(UISwipeGestureRecognizer *)sender{

    CGPoint location = [_gestureSwipeLeft locationInView:_tblThingsToDo];
    NSIndexPath *swipedIndexPath = [_tblThingsToDo indexPathForRowAtPoint:location];
    _indexPath = swipedIndexPath;
    UITableViewCell *swipedCell  = [_tblThingsToDo cellForRowAtIndexPath:swipedIndexPath];

    if (swipedCell.selected == NO) {
        swipedCell.selected = YES;
    } else{
        swipedCell.selected = NO;
    }
}


-(void)deleteCurrentobject:(id)sender{
     if(self.selectedCells){
         [_things removeObjectAtIndex:_indexPath.row];
         [self.tblThingsToDo beginUpdates];
         [self.tblThingsToDo deleteRowsAtIndexPaths:[NSArray arrayWithObject:_indexPath] withRowAnimation:UITableViewRowAnimationFade];
         [self.tblThingsToDo endUpdates];
     }
}

从UITableView中删除选定的单元格

2 个答案: