Question

我用2个部分创建了一个tableview，我在tableview中显示了数据的数组..现在我想展开并折叠部分...... 我只是一个初学者，请提供任何示例代码以展开和折叠tableview部分...

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
    return 2;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    return [arraytable count];
}

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

    if (!cell) {
        cell = [[UITableViewCell alloc]initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellitem];
    }

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

    return cell;
}

这是我的cellForRowAtIndexPath和arraytable是我的数组我在视图中给它加载

arraytable = @[@"hari12",@"narayanan",@"Praba",@"Deepak",@"Sailesh",@"Ram charan"];

Answer 1

这是我为实现您的目标而制作的示例代码。

您可以将此作为一般指导原则，因为除了我所做的以外，有很多方法可以实现这一目标。

我从上面的例子中注意到你有一个包含2个部分的表视图，所以这就是我将用于示例代码的内容。

可能有更好的方法来实现下面的内容，但这是最重要的，我认为它非常简单明了。
我还在下面的代码中包含了解释作为评论请注意，您可能需要更改某些变量的名称以适合您的代码（例如self.tableView，如果您使用其他内容）和section1DataArray，section2DataArray

// I've declared 2 BOOL properties to hold whether each section is visible or not  
@interface ViewController ()  
@property (nonatomic) BOOL section1visible, section2visible;  
@end  

-(void)viewDidLoad {  
    // After creating the table view, I've set the footer view frame to CGRectZero,  
    // so when a table view is collapsed you won't have the table columns 'bounds'  
    self.tableView.tableFooterView = [[UIView alloc] initWithFrame: CGRectZero];  
}  

// Then I've created a custom header for each table since I've wanted to make the header  
// name a button which collapse/expand the table view.  
-(CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section {  
    // Here I've set the height arbitrarily to be 50 points  
    return 50;  
}  

-(UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section {  
    // Change the below frame to fit your needs. In my example, I've used a table view  
    // to be at the width of the screen, and the height of 50 points (as we've set above)
    UIView *header = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, 50)];  
    // Then create a button  
    // I've arbitrarily chosen a size of 100x20 and created a frame to be placed in the  
    // middle of the above header
    UIButton *button = [[UIButton alloc] initWithFrame:CGRectMake(header.frame.size.width/2 - 50, header.frame.size.height/2 - 10, 100, 20)];  

    // Now I'm setting the tag (for later use) and title of each button  
    if(section == 0) { // First section  
        [button setTitle:@"Section 1" forState:UIControlStateNormal];  
        button.tag = 0;  
    } else { // Else, second section, since we only have two  
        [button setTitle:@"Section 2" forState:UIControlStateNormal];  
        button.tag = 1;  
    }  

    // I've arbitrarily chose to set the button colour to gray colour  
    button.titleLabel.textColor = [UIColor grayColor];  
    // Then we need to actually add an action to the button  
    [button addTarget:self action:@selector(updateTableView:) forControlEvents:UIControlEventTouchUpInside];  
    // Then we need to add the button to the header view itself  
    [header addSubview:button];  

    return header;  
}  

// Then we need to update our tableView:numberOfRowsInSection: to check for our BOOL value  
-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {  
    if(section == 0 && self.section1visible) {  
        return [self.section1DataArray count];  
    } else if (section == 1 && self.section2visible) {  
        return [self.section2DataArray count];  
    } else {  
        return 0;  
    }  
}  

// Then we need to create the actual method the button calls  
-(void)updateTableView:(UIButton *)sender {  
    // Check the button tag, to identify which header button was pressed  
    NSInteger section = sender.tag;  

    if(section == 0) {  
        self.section1visible = !self.section1visible;  
    } else { // section == 1  
        self.section2visible = !self.section2visible;  
    }  

    // Use an animation to update the UI to create a 'smooth' expand/collapse  
    [self.tableView reloadSections:[NSIndexSet indexSetWithIndex:section] withRowAnimation:UITableViewRowAnimationFade];  
}

祝你好运。

在iOS中展开和折叠tableview的方法

1 个答案: