Ios Pickerview显示两侧的值

如何删除选择器视图左侧的值？两个PickerView分别滚动，似乎两个picker视图并排打开

情况就是这样：

extension SignUpVC : UITextFieldDelegate {

func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {
    
    if textField == genderTF {
    }
    return true
}}

extension SignUpVC : UIPickerViewDelegate , UIPickerViewDataSource {
func numberOfComponents(in pickerView: UIPickerView) -> Int {
   return genderArr.count
}

func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int{
    return genderArr.count
}

func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
    return genderArr[row]
}

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int){
    genderTF.text = genderArr[row]
    self.view.endEditing(true)
}}

我的代码：

extension SignUpVC : UITextFieldDelegate {

func textFieldShouldBeginEditing(_ textField: UITextField) -> Bool {
    
    if textField == genderTF {
    }
    return true
}}

extension SignUpVC : UIPickerViewDelegate , UIPickerViewDataSource {
func numberOfComponents(in pickerView: UIPickerView) -> Int {
   return genderArr.count
}

func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int{
    return genderArr.count
}

func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
    return genderArr[row]
}

func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int){
    genderTF.text = genderArr[row]
    self.view.endEditing(true)
}}

---

func numberOfComponents（在pickerView:UIPickerView中）->Int{return 1}非常感谢兄弟。。。成功了：-）