UITableView 多个部分，带有 GUI 元素 UIButton、UISwitch 等答案

【问题标题】：UITableView multiple sections with GUI Elements UIButton, UISwitch, etcUITableView 多个部分，带有 GUI 元素 UIButton、UISwitch 等
【发布时间】：2011-10-25 20:52:43
【问题描述】：

我已经在这个问题上绞尽脑汁了一天左右...我已经搜索了这个论坛以及谷歌和其他博客等。都无济于事。

我正在做的是创建一个包含多个部分的UITableView，并且在每个部分中，每一行都有不同的 GUI 元素（即设置屏幕）

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
    return 3;
}

我想要实现的只是每个部分在不同的单元格中都有不同的 GUI 元素。但是正如您在此屏幕截图中看到的那样：

最初一切都按原样显示，但在向上和向下滚动一次后，问题就开始了。元素开始四处移动，向上和向下滚动的次数越多/时间越长，元素移动的次数就越多。

!["UITableView 在部分和行中带有 GUI 元素。错误？故障？无知？"][2]

这是一个错误吗？毛刺？还是无知？（可能是后者）-我已经删除了除 GUI 代码之外的所有其他代码，如果它意味着任何我正在使用 NIB 创建UITableView

另外，这是我的cellForRowAtIndexPath 方法的代码。如果有人能指出我正确的方向或告诉我我做错了什么，我将永远感激不尽。

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

    static NSString *CellIdentifier = @"Cell";

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithFrame:CGRectZero reuseIdentifier:CellIdentifier] autorelease];
    }


    // Set up the cell
    // desired section
    if(indexPath.section == 0) {
        //
        //  Load Settings
        //

        // button
        UIButton * loadButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
        loadButton.frame = CGRectMake(0.0, 0.0, 300.0, 44.0);
        [loadButton setTitle:@"Load Image" forState:UIControlStateNormal];
        [loadButton setTitle:@"Load Image" forState:UIControlStateSelected];
        [loadButton addTarget:self action:@selector(loadImage:) forControlEvents:UIControlEventTouchUpInside];
        [cell.contentView addSubview:loadButton]; 


    } else if(indexPath.section == 1) {
        //
        //  Mode Settings
        //
        if(indexPath.row == 0) {
            cell.text = [mode objectAtIndex:indexPath.row];    
        } else if(indexPath.row == 1) {
            cell.text = [mode objectAtIndex:indexPath.row];    
        }


    } else if(indexPath.section == 2) {
        //
        //  Marker Settings
        //

        if(indexPath.row == 0) {
            // description text
            cell.text = [marker objectAtIndex:indexPath.row];    

            // switch
            UISwitch *markerSwitch = [[UISwitch alloc] initWithFrame:CGRectZero];
            cell.accessoryView = markerSwitch;
            [markerSwitch setOn:YES animated:NO];
            [markerSwitch addTarget:self action:@selector(markerToggle:) forControlEvents:UIControlEventValueChanged];
            [markerSwitch release];       

        } else if(indexPath.row == 1) {
            UISlider *markerGridSlider = [[UISlider alloc] initWithFrame:CGRectMake(0.0, 10.0, 284, 10.0)];
            cell.accessoryView = markerGridSlider;
            markerGridSlider.minimumValueImage = [UIImage imageNamed:@"size_icon_1x1.png"];
            markerGridSlider.maximumValueImage = [UIImage imageNamed:@"size_icon_8x8.png"];

            [markerGridSlider setMinimumValue:1.0];
            [markerGridSlider setMaximumValue:8.0];
            markerGridSlider.value = 8.0;
            [markerGridSlider addTarget:self action:@selector(markerGrid:) forControlEvents:UIControlEventValueChanged];
            [markerGridSlider release];       

        } else if(indexPath.row == 2) {
            UISlider *markerSpacingSlider = [[UISlider alloc] initWithFrame:CGRectMake(0.0, 10.0, 284, 10.0)];
            cell.accessoryView = markerSpacingSlider;
            markerSpacingSlider.minimumValueImage = [UIImage imageNamed:@"spacing_icon_min.png"];
            markerSpacingSlider.maximumValueImage = [UIImage imageNamed:@"spacing_icon_max.png"];

            [markerSpacingSlider setMinimumValue:1.0];
            [markerSpacingSlider setMaximumValue:(320.0/8.0)];
            markerSpacingSlider.value = 1.0;
            [markerSpacingSlider addTarget:self action:@selector(markerSpacing:) forControlEvents:UIControlEventValueChanged];
            [markerSpacingSlider release];       
        }
    }

    return cell;
}

谢谢。

肯

非常感谢您的帮助。

也许我不明白你的意思，但我认为我已经正确地实施了你的建议。但是我仍然得到元素交换位置的故障，尽管现在经过大约 5 次以上的向上和向下滑动并且我的 UISwitch 现在被放置在左上角。

这是我更新的代码：

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

    static NSString *CellIdentifier = @"Cell";

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];

    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];



        if([indexPath section] == 0) {
            //
            // Load Settings
            //

            // button
            UIButton *loadButton = [[UIButton buttonWithType:UIButtonTypeRoundedRect] autorelease];
            loadButton.frame = CGRectMake(0.0, 0.0, 300.0, 44.0);
            [loadButton addTarget:self action:@selector(loadImage:) forControlEvents:UIControlEventTouchUpInside];
            [loadButton setTag:1000];

            [cell.contentView addSubview:loadButton]; 

        } 



        if([indexPath section] == 1) {
            //
            // Mode Settings
            //
            if([indexPath row] == 0) {
                cell.text = [mode objectAtIndex:[indexPath row]];    
            }
            if([indexPath row] == 1) {
                cell.text = [mode objectAtIndex:[indexPath row]];    
            }
        } 



        if([indexPath section] == 2) {
            //
            // Marker Settings
            //
            if([indexPath row] == 0) {
                // switch
                UISwitch *markerSwitch = [[UISwitch alloc] initWithFrame:CGRectZero];
                [markerSwitch setOn:YES animated:NO];
                [markerSwitch addTarget:self action:@selector(markerToggle:) forControlEvents:UIControlEventValueChanged];
                [markerSwitch setTag:3000];

                [cell.contentView addSubview:markerSwitch]; 
                [markerSwitch release];

            }
            if([indexPath row] == 1) {
                // slider
                UISlider *markerGridSlider = [[UISlider alloc] initWithFrame:CGRectMake(0.0, 10.0, 284, 10.0)];
                markerGridSlider.minimumValueImage = [UIImage imageNamed:@"size_icon_1x1.png"];
                markerGridSlider.maximumValueImage = [UIImage imageNamed:@"size_icon_8x8.png"];

                [markerGridSlider setMinimumValue:1.0];
                [markerGridSlider setMaximumValue:8.0];
                [markerGridSlider setValue:8.0];
                [markerGridSlider addTarget:self action:@selector(markerGrid:) forControlEvents:UIControlEventValueChanged];
                [markerGridSlider setTag:3100];

                [cell.contentView addSubview:markerGridSlider]; 
                [markerGridSlider release];

            }
            if([indexPath row] == 2) {
                // slider
                UISlider *markerSpacingSlider = [[UISlider alloc] initWithFrame:CGRectMake(0.0, 10.0, 284, 10.0)];
                markerSpacingSlider.minimumValueImage = [UIImage imageNamed:@"spacing_icon_min.png"];
                markerSpacingSlider.maximumValueImage = [UIImage imageNamed:@"spacing_icon_max.png"];

                [markerSpacingSlider setMinimumValue:1.0];
                [markerSpacingSlider setMaximumValue:(320.0/8.0)];
                [markerSpacingSlider setValue:1.0];
                [markerSpacingSlider addTarget:self action:@selector(markerSpacing:) forControlEvents:UIControlEventValueChanged];
                [markerSpacingSlider setTag:3200];

                [cell.contentView addSubview:markerSpacingSlider]; 
                [markerSpacingSlider release];

            }
        }


    } // end cell == nil


    // Load
    UIButton *loadButton = (UIButton*)[cell.contentView viewWithTag:1000];
    [loadButton setTitle:@"Load Image" forState:UIControlStateNormal];
    [loadButton setTitle:@"Load Image" forState:UIControlStateSelected];

    // Mode

    // Marker
    UISwitch *markerSwitch = (UISwitch*)[cell.contentView viewWithTag:3000];
    UISlider *markerGridSlider = (UISlider*)[cell.contentView viewWithTag:3100];
    UISlider *markerSpacingSlider = (UISlider*)[cell.contentView viewWithTag:3200];


    return cell;
}

【问题讨论】：

标签： objective-c user-interface uitableview

【解决方案1】：

iOS 中绑定到 UITable 的所有单元格都是可重用。这就是为什么您首先使用函数调用“dequeueReusableCellWithIdentifier”获取单元格的原因，该单元格可能不是零，指向之前加载的单元格。在您的情况下，即使单元格不为零，您也可以向其中添加子视图。当您上下滚动时，这将无限次发生。

这是一个小例子：

-(int)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    return 2;
}

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

    const NSInteger lblTag = 101;
    const NSInteger btnTag = 102;

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];

    //First init the cells
    if (cell == nil) {
        cell = [[[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier] autorelease];

        //Initialize subviews of cells only in this block.

        if (indexPath.row == 0) {
            //Only the first cell on the top has a UILabel
            UILabel *lbl = [[[UILabel alloc] initWithFrame:CGRectMake(5, 5, 100, 20)] autorelease];
            lbl.tag = lblTag;    
            [cell.contentView addSubview:lbl];
        } else if (indexPath.row == 1) {
            //Only the 2nd cell has a UIButton
            UIButton *btn = [UIButton buttonWithType:UIButtonTypeRoundedRect];
            btn.frame = CGRectMake(5, 5, 60, 20);
            btn.tag = btnTag;    
            [cell.contentView addSubview:btn];
        }
    }

    //Modify your cells here
    if (indexPath.row == 0) {
        //Only the first cell on the top has a UILabel
        UILabel *lbl = (UILabel*)[cell.contentView viewWithTag:lblTag];
        //Do stuff with our label

        lbl.text = [NSString stringWithFormat:@"%d",indexPath.row];

    } else if (indexPath.row == 1) {
        //Only the 2nd cell has a UIButton
        UIButton *btn = (UIButton*)[cell.contentView viewWithTag:btnTag];
        //Do stuff with our button
        [btn setTitle:[NSString stringWithFormat:@"%d",indexPath.row] forState:UIControlStateNormal];

    }

    return cell;

}

在您的非常特定情况下，您会这样写-

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section 
{
    if (section == 0) {
        return 1;
    } else if (section == 1) {
        return 2;
    } else if (section == 2) {
        return 3;
    } else {
        return 0;
    }
}

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

    static NSString *CellIdentifier = @"Cell";



    const NSInteger
    sec0BtnTag = 101,
    markerSwitchTag = 102,
    markerGridSliderTag = 103,
    markerSpacingSliderTag = 104;

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



        if([indexPath section] == 0) {
            //
            // Load Settings
            //

            // button
            UIButton *loadButton = [[UIButton buttonWithType:UIButtonTypeRoundedRect] autorelease];
            loadButton.frame = CGRectMake(0.0, 0.0, 300.0, 44.0);
            [loadButton addTarget:self action:@selector(loadImage:) forControlEvents:UIControlEventTouchUpInside];
            [loadButton setTag:sec0BtnTag];

            [cell.contentView addSubview:loadButton]; 

        } 



        else if([indexPath section] == 2) {
            //
            // Marker Settings
            //
            if([indexPath row] == 0) {
                // switch
                UISwitch *markerSwitch = [[UISwitch alloc] initWithFrame:CGRectZero];
                [markerSwitch setOn:YES animated:NO];
                [markerSwitch addTarget:self action:@selector(markerToggle:) forControlEvents:UIControlEventValueChanged];
                [markerSwitch setTag:markerSwitchTag];

                [cell.contentView addSubview:markerSwitch]; 
                [markerSwitch release];

            }
            else if([indexPath row] == 1) {
                // slider
                UISlider *markerGridSlider = [[UISlider alloc] initWithFrame:CGRectMake(0.0, 10.0, 284, 10.0)];
                markerGridSlider.minimumValueImage = [UIImage imageNamed:@"size_icon_1x1.png"];
                markerGridSlider.maximumValueImage = [UIImage imageNamed:@"size_icon_8x8.png"];

                [markerGridSlider setMinimumValue:1.0];
                [markerGridSlider setMaximumValue:8.0];
                [markerGridSlider setValue:8.0];
                [markerGridSlider addTarget:self action:@selector(markerGrid:) forControlEvents:UIControlEventValueChanged];
                [markerGridSlider setTag:markerGridSliderTag];

                [cell.contentView addSubview:markerGridSlider]; 
                [markerGridSlider release];

            }
            else if([indexPath row] == 2) {
                // slider
                UISlider *markerSpacingSlider = [[UISlider alloc] initWithFrame:CGRectMake(0.0, 10.0, 284, 10.0)];
                markerSpacingSlider.minimumValueImage = [UIImage imageNamed:@"spacing_icon_min.png"];
                markerSpacingSlider.maximumValueImage = [UIImage imageNamed:@"spacing_icon_max.png"];

                [markerSpacingSlider setMinimumValue:1.0];
                [markerSpacingSlider setMaximumValue:(320.0/8.0)];
                [markerSpacingSlider setValue:1.0];
                [markerSpacingSlider addTarget:self action:@selector(markerSpacing:) forControlEvents:UIControlEventValueChanged];
                [markerSpacingSlider setTag:markerSpacingSliderTag];

                [cell.contentView addSubview:markerSpacingSlider]; 
                [markerSpacingSlider release];

            }
        }


    } // end cell == nil

    //Load specific cell row values

    if([indexPath section] == 0) {
        //
        // Load Settings
        //

        // button
        UIButton *loadButton = (UIButton*)[cell.contentView viewWithTag:sec0BtnTag];
        [loadButton setTitle:@"Load Image" forState:UIControlStateNormal];
        [loadButton setTitle:@"Load Image" forState:UIControlStateSelected];
        //do other stuff with the button here according to the specific row & section

    } 



    if([indexPath section] == 1) {
        //
        // Mode Settings
        //
        if([indexPath row] == 0) {
            cell.text = [mode objectAtIndex:[indexPath row]];    
        }
        if([indexPath row] == 1) {
            cell.text = [mode objectAtIndex:[indexPath row]];    
        }
    } 



    if([indexPath section] == 2) {
        //
        // Marker Settings
        //
        if([indexPath row] == 0) {
            // switch
            UISwitch *markerSwitch = (UISwitch*)[cell.contentView viewWithTag:markerSwitchTag];
            //do stuff with the switch here according to the specific row & section
        }
        if([indexPath row] == 1) {
            // slider
            UISlider *markerGridSlider = (UISlider*)[cell.contentView viewWithTag:markerGridSliderTag];
            //do stuff with the slider here according to the specific row & section
        }
        if([indexPath row] == 2) {
            // slider
            UISlider *markerSpacingSlider = (UISlider*)[cell.contentView viewWithTag:markerSpacingSliderTag];
            //do stuff with the slider here according to the specific row & section



        }
    }


    return cell;
}

【讨论】：

好的。我可能不完全理解你的意思。虽然我认为我已经实施了你的建议。大约需要 5 次以上的 UP 和 DOWN 才能恢复故障，但它仍然存在。
修改了我的答案。请参阅包含的示例。

【解决方案2】：

为每个部分更改 static NSString *CellIdentifier = @"Cell";，例如：

NSString *CellIdentifier; if(indexPath.section==0){ CellIdentifier= @"Cell"; }elseif(indexPath.section==2){ CellIdentifier=@"Cell2"; }

【讨论】：