iPhone中的UIPickerview？

Question

我是Objective-C的新手，我需要在触摸特定文本字段时创建一个UIPickerView，该文本字段将填充NSMutableArray的项目..我已经实现了此代码，但看不到添加的pickerView。我仍然可以看到键盘触摸文本字段时弹出......我哪里错了......？

- (BOOL)textFieldDidBeginEditing:(UITextField *)textField {

    if( textField == txtstate)
    {
        [txtstate resignFirstResponder];
        pickerView = [[UIPickerView alloc] initWithFrame:CGRectMake(0, 200, 320, 200)];

        pickerView.delegate = self;
        pickerView.dataSource = self;
        pickerView.showsSelectionIndicator = YES;
    [self.view addSubview:pickerView];

    }

    }
  - (NSInteger)numberOfComponentsInPickerView:(UIPickerView *)pickerView;
   {
return 1;
   }

  - (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component
  {
 [pickerView selectRow:1 inComponent:0 animated:NO];

txtstate.text= [[arr objectAtIndex:row] valueForKey:@"Code"]; 
  }

 - (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component;
  {
return [arr count];
  }

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

 return [arr objectAtIndex:row];
 }  

我的阵列看起来像这样：

(
{
        Code = Wisconsin;
        Id = "6215b339-2959-4a3d-9430-f5bddb0a4eb9";
    },
        {
        Code = Wyoming;
       Id = "7972f963-9b3b-4ba6-a30c-d68bb9f59145";
    }
)

任何帮助，将不胜感激...

Answer 1

u can add button on UITextField and add your picker at that button action .

确保您的按钮应该是自定义类型按钮并将该按钮放在文本字段上。

Answer 2

如果你没有给UITextField名称txtstate的委托，那么在viewDidLoad:方法中像下面那样给委托

txtstate.delegate = self;