Question

我的UITableViews的第一行都是空白的，即使我的NSLog在函数tableView .. cellForRowAtIndexPath中，显示第0,1,2，...行是调用并初始化。

我并排制作了四个UITableViews，每个都有40行。 NSLog显示所有40行都调用了带有cellForRowAtIndexPath的函数，但每个显示行0都是空的。显示的第1行包含我期望在第0行的单元格，第2行包含第1行的单元格，等等。

这是创建UITableView数据结构的代码，以及构建其单元格的函数cellForRowAtIndexPath。

这是.m文件范围级别（开头）的四个UITableViews数组：

UITableView* channel_tableView[ TOTAL_TX_CHANNELS ];

这里是在函数viewDidLayoutSubviews中创建UITableViews的地方：

    for( int channel=0; channel < TOTAL_TX_CHANNELS; ++channel )
    {
        // Create channel_tableView:

            CGRect tableFrame = CGRectMake(x, y, width, height);

            channel_tableView[ channel ] = [[UITableView alloc]initWithFrame:tableFrame style:UITableViewStylePlain];

            channel_tableView[ channel ].rowHeight = channel_row_height;
            channel_tableView[ channel ].sectionFooterHeight = 0;
            channel_tableView[ channel ].sectionHeaderHeight = 0;
            channel_tableView[ channel ].scrollEnabled = YES;
            //new_channel_tableView.showsVerticalScrollIndicator = YES;
            channel_tableView[ channel ].userInteractionEnabled = YES;
            channel_tableView[ channel ].bounces = YES;

            channel_tableView[ channel ].delegate = self;
            channel_tableView[ channel ].dataSource = self;

        //  channel_tableView[ channel ].autoresizingMask = UIViewAutoresizingFlexibleHeight|UIViewAutoresizingFlexibleWidth;
            [channel_tableView[ channel ]  reloadData];             // display channel's TableView
            [[self view] addSubview:   channel_tableView[ channel ]];
    }

这是创建所有单元格的函数：

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    NSLog( @"cellForRowAtIndexPath");
    NSLog( @"   %d  = row", indexPath.row  );



    UITextView*  test_textView;
    UITextView*  test_2nd_textView;
    UITextView*  test_3rd_textView;


    // Determine which channel_tableView:
        int channel;
        for( channel = 0; channel < TOTAL_TX_CHANNELS; ++channel )
        {
            if( tableView == channel_tableView[ channel ] )
                break;
        }
        // channel = tableView's channel
        NSLog( @"   %d  = channel", channel  );

    // DOCUMENTATION:  Table View Programming Guide for iOS > Adding subviews to a cellís content view
    // Give each cell a cell identifier unique to each channel tableView and unique to each row, so that each gets a unique data structure:
            NSString *CellIdentifier = [NSString stringWithFormat:@"%d_%d",channel,indexPath.row];

    //static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
        // if nil: cell(chan, row) has not been created before.  <>nil: cell = data structure previously initialized
    if (cell == nil)
    {
        NSLog( @"       cell nil");
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier: CellIdentifier];
        /* Though it's UITableViewCellStyleDefault, the three defaults (image, label, detail label) are nil
        if not set. */
    }
        // Add UITextView for channel pipe to cell:
            int pipe_width = 20;
            int w = pipe_width;
            int x = channel_tableView_width/2 - pipe_width/2;
            int h = channel_row_height;
            int y = 0;
            test_textView = [[UITextView alloc] initWithFrame:CGRectMake    (x,y, w,h)] ;
            [test_textView setFont:[UIFont boldSystemFontOfSize:8.0]];
            [test_textView setEditable:NO];
            [test_textView setTextAlignment:NSTextAlignmentCenter];
            // Round the corners and set border color
            if(channel == power_channel )
                [test_textView setBackgroundColor:[UIColor greenColor]];
            else
                [test_textView setBackgroundColor:[UIColor whiteColor]];
            [[test_textView layer] setBorderColor:[[UIColor blackColor] CGColor]];
            [[test_textView layer] setBorderWidth:1];
            //[[test_textView layer] setCornerRadius:15];
            [test_textView setClipsToBounds: YES];


        // Add UITextView for PWR RX to cell:
        int PWR_RX_width = channel_tableView_width/2;
         y = y + h ;
         w = PWR_RX_width;
         x = channel_tableView_width/2 - PWR_RX_width/2;
         h = 20;
            test_2nd_textView = [[UITextView alloc] initWithFrame:CGRectMake    (x,y, w,h)];
            [test_2nd_textView setFont:[UIFont boldSystemFontOfSize:8.0]];
            [test_2nd_textView setEditable:NO];
            [test_2nd_textView setTextAlignment:NSTextAlignmentCenter];
            // Round the corners and set border color
            [test_2nd_textView setBackgroundColor:[UIColor whiteColor]];
            [[test_2nd_textView layer] setBorderColor:[[UIColor blackColor] CGColor]];
            [[test_2nd_textView layer] setBorderWidth: 1];
            //[[test_2nd_textView layer] setCornerRadius:15];
            [test_2nd_textView setClipsToBounds: YES];      

        // Add UITextView for device to cell:
        int device_width = channel_tableView_width/2;
         y = y + h-3;
         w = device_width;
         x = channel_tableView_width/2 - device_width/2;
         h = 40;
            test_3rd_textView = [[UITextView alloc] initWithFrame:CGRectMake    (x,y, w,h)];
            [test_3rd_textView setFont:[UIFont boldSystemFontOfSize:8.0]];
            [test_3rd_textView setEditable:NO];
            [test_3rd_textView setTextAlignment:NSTextAlignmentCenter];
            // Round the corners and set border color  
            [test_3rd_textView setBackgroundColor:[UIColor whiteColor]];
            [[test_3rd_textView layer] setBorderColor:[[UIColor blackColor] CGColor]];
            [[test_3rd_textView layer] setBorderWidth: 1];
            //[[test_3rd_textView layer] setCornerRadius:15];
            [test_3rd_textView setClipsToBounds: YES];

        /*
                test_textView.tag = TEST_TEXTVIEW_TAG;
                test_2nd_textView.tag = TEST_2ND_TEXTVIEW_TAG;
                test_3rd_textView.tag = TEST_3RD_TEXTVIEW_TAG;

        test_textView     = (UITextView*)[cell.contentView viewWithTag: TEST_TEXTVIEW_TAG];
        test_2nd_textView = (UITextView*)[cell.contentView viewWithTag: TEST_2ND_TEXTVIEW_TAG];
        test_3rd_textView = (UITextView*)[cell.contentView viewWithTag: TEST_3RD_TEXTVIEW_TAG];
         */
    //[test_textView setText:     [NSString stringWithFormat: @"pipe-%d", indexPath.row ]];
    [test_2nd_textView setText: [NSString stringWithFormat: @"PWR RX %d", indexPath.row + 1 ]];
    [test_3rd_textView setText: [NSString stringWithFormat: @"device %d", indexPath.row + 1 ]];
            // Add created UI objects to cell[ indexPath.row ]:
                [cell.contentView addSubview:test_textView ];
                [cell.contentView addSubview:test_2nd_textView ];
                [cell.contentView addSubview:test_3rd_textView ];
    return cell;
}

SCREENSHOT显示BLANK ROW-0 ..............................

enter image description here

Answer 1

您的test_2nd_textView和test_3rd_textView被绘制在第一个表格单元格之外（不是裁剪），因为您正在使用y>=cell_height的框架初始化它们。对于test_textView，y=0, h=cell_height。对于test_2nd_textView，y=cell_height和h=20，因此test_2nd_textView位于第二个单元格的顶部。

UITableView第一个单元格没有设置

1 个答案: