从动态类引用动态设置器 [英] Referencing a dynamic setter from a dynamic class

问题描述

我正在尝试引用一个setter ...我收到帮助，并在解决问题之前选择了答案....看到这里：在表单外使用setter？

I am trying to reference a setter... I received help and selected the answer too soon before resolving the issue.... see here: Using a setter from outside a form?

所以，我在做什么这个...数据进入日志，它被解析，然后它返回到显示的表单。

So, what I'm doing is this... Data goes into the log and it gets parsed, then it goes back to the form where it is displayed.

public class Log {
   private MainForm mainForm; // our MainForm variable

   public Log(MainForm mainForm) {
      // setting the MainForm variable to the correct reference in its constructor
      this.mainForm = mainForm;  
   }

   private  void consoleOut(String data) {
     System.out.println(data);
     if (mainForm != null) {
        // now we can use the reference passed in.
        mainForm.setConsoleText("data");
     }
   }
}

这是我表单中的设置者。

Here's the setter in my form.

public class MainForm extends FrameView {
    public MainForm(SingleFrameApplication app) {
        super(app);
...........CUT FOR LENGTH.................
    public void setConsoleText(String Text){
        jTextArea2.append(Text);
    }

为简单起见，编辑

由于某种原因，MainForm在Log类中总是出现null。

For some reason MainForm always comes out null in the Log class.

如何获得对我的主窗体的引用？

How can I get a reference to my Main form?

嗯...我刚刚去了一个静态文本框和静态设置器....仍在寻找一个更好的主意。

Meh... I just went with a static textbox and a static setter.... Still looking for a better idea.

推荐答案

唯一的解释是，当您实例化日志时，您将传递一个null到构造函数。在 mainform被分配之前，您是否正在调用新的日志（主窗体） ？

The only explanation is that when you are instantiating Log you are passing a null to the constructor. Are you calling new Log(mainform) before mainform has been assigned?

// Don't do this
private Log log = new Log(mainForm);

private MainForm mainForm = new MainForm();

检查对象的构造顺序。

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