Question

我有一个名为BuyCoins的类，在这个类中我有一个方法addListenerOnSpinnerItemSelection（）

   Sub consolidate(z)
      Sheets(z).Range("B1:AXH100").Delete '''deletes former values'''
      For i = 1 To 30
      For x = 1 To 500
      If IsEmpty(Sheets("Sheet1").Cells(x, 13)) Then 'if cell value is empty skip it'
          a = 1
      Else:
          If Sheets("Sheet1").Cells(x, 18) = Sheets(z).Cells(1, 1) Then 'check to see if value is same'
          If Sheets("Sheet1").Cells(x, 13) = Sheets(z).Cells(i, 1) Then 'check to see if value is same'
              Sheets("Sheet1").Cells(x, 15).Copy 'copy value'
              Sheets(z).Select 'select second sheet'
              Cells(i, 1).Select
              ActiveSheet.Cells(ActiveCell.Row, Columns.Count).End(xlToLeft).Offset(0, 1).Select 'offsets cell to the
  left'
              Selection.PasteSpecial past:=xlPasteValues 'pastes'
      End Sub

这会创建一个新对象，用于检测在微调器上选择的项目（产品）。我想把它传回BuyClass。我试图用注释掉的行来做这个，但是我收到的值是null。

series: [{
    name: 'companyA',
    data: results[0]
}, {
    name: 'companyB',
    data: results[1]
}]

Answer 1

问题是你在添加后立即查询监听器，即事件不可能发生。由于你不知道偶然发生了什么（如果有的话），你需要将它解耦。

示例（简单的伪代码，只是为了让您入门）：

class Model {
  String stock;
}

class Listener {
  Model model;

  Listener( Model m) {
    model = m;
  }

  //In your case Component might be the spinner or its parent, depending on the rest of your code
  void onItemSelected( Component c ) {
    m.stock = c.getText();
  }
}

当您创建并注册监听器时：

class BuyCoins {
  Model model;  //initialize 

  ...

  void initListeners() {
    spinner.addListener( new Listener(model) );
  }
}

Answer 2

感谢大家，设法通过在后续活动中添加以下内容来解决问题。

public void onBuyCoinButtonClicked(View arg0) {

    spinner1 = (Spinner) findViewById(R.id.spinner1);
    String product= spinner1.getSelectedItem().toString();
    Toast.makeText(this,
            "product : " + product,
            Toast.LENGTH_SHORT).show();

简易解决方法

回调函数java

2 个答案: