选择器视图在选择器视图中显示数字但未在标签上正确显示？

Posted 2023-02-24

【中文标题】选择器视图在选择器视图中显示数字但未在标签上正确显示？

【英文标题】：picker view shows numbers in pickerview but not showing properly on label?

【发布时间】：2009-10-11 08:41:14

【问题描述】：

我已经从界面生成器中添加了一个pickerview。我正在使用这种方法来显示这样的数据......

- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component

if (pickerView == SpotPickerView) // don't show selection for the custom picker

  // report the selection to the UI label
 label.text = [NSString stringWithFormat:@"%d - %@ - %d",[pickerView selectedRowInComponent:0],
   [RowArray objectAtIndex:[pickerView selectedRowInComponent:1]],
   [pickerView selectedRowInComponent:2]];




- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component

 NSString *returnStr = @"";
 if (pickerView == SpotPickerView)
 
  if (component == 0)
  
    returnStr = [[NSNumber numberWithInt:row+1] stringValue];
  
  else if(component==1)
  
    returnStr = [RowArray objectAtIndex:row];
  
else
 
   returnStr =[[NSNumber numberWithInt:row+1] stringValue];
  


  return returnStr;


- (CGFloat)pickerView:(UIPickerView *)pickerView widthForComponent:(NSInteger)component

  CGFloat componentWidth = 0.0;

  if (component == 0)
  componentWidth = 90.0;
  else if (component == 1)
  componentWidth = 100.0; 
  else 
  componentWidth = 90.0; 

  return componentWidth;


- (CGFloat)pickerView:(UIPickerView *)pickerView rowHeightForComponent:(NSInteger)component
 
   return 40.0;
 

- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component

   int count;
   if (component == 0)
   count = 15;
  else if (component == 1)
   count=[RowArray count]; 
 else 
  count = 100;

 return count;


- (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView

   return 3;

这里是行数组

- (void)viewDidLoad 
RowArray = [[NSArray arrayWithObjects:
  @"A", @"B", @"C",
  @"D", @"E", @"F", @"G",@"H",@"I",@"J",@"K",@"L",@"M",@"N",@"O",@"P",@"Q",@"R",@"S",@"T",
  @"U",@"V",@"W",@"X",@"Y",@"Z",
  nil] retain];

但选择第一行会显示这一点。

我需要将值存储在数据库中，所以我需要 1 而不是零。

我如何重置我的选择器视图。意味着当我点击一个按钮时，它会自动到达每列中的第 0 个索引。

【参考方案1】：

label.text = [NSString stringWithFormat:@"%d - %@ - %d",[pickerView selectedRowInComponent:0],
    [RowArray objectAtIndex:[pickerView selectedRowInComponent:1]],
    [pickerView selectedRowInComponent:2]];

此代码正在从组件中的选定行中检索行号。数组是零索引的，pickerview（可能）使用数组来管理行。因此，第一行将为 0，第二行为 1，第三行为 2，依此类推。这很容易解决：

[pickerView selectedRowInComponent:0] + 1

您可以使用selectRow:inComponent:animated 以编程方式选择某些行如果您想在每列中选择第 0 个索引，只需执行以下操作：[pickerView selectRow:0 inComponent:0 animated:YES] 用于每个组件。