如何从另一个子窗口访问子窗口控件 [英] How to access the child window control from another child window

问题描述

我有父窗口，上面有tabControl。然后我在另一个tabControl中显示了另外两个子窗口。在child1中，我有CEdit控件，因此在child2中也是如此。 child2中的CEdit是一个CEdit，它在child1中按下enter按钮时显示来自child1中CEdit的一些文本。问题是每当我点击child1中的输入按钮时，我都会收到错误。我在输入按钮中使用此代码：

I have parent window that has tabControl on it. Then i have made 2 other child window that shown in to that tabControl. In the child1, i have CEdit control and so also in the child2. CEdit in the child2 is a CEdit that show some text from CEdit in the child1 when press enter button in child1. the problem is that whenever i hit the enter button in child1 i get an error. I use this code in enter button :

void child_1::OnBnClickedEnter()
{
    CString CSText;
    m_EnterTextField.GetWindowText(CSText);
    m_View = (CEdit *) GetDlgItem(CE_Child2);//CE_Child2 is the ID from CEdit control in Child2
    m_View->SetWindowText(CSText);//the problem is in here
}

谢谢...：）

thanks... :)

推荐答案

GetDlgItem（）函数检索指向窗口内指定控件或子窗口的指针，以便调用该函数。您正在使用此窗口中不存在的ID从 child_1 窗口调用此函数，该函数将返回NULL。要在另一个窗口中获取指向控件的指针，必须为该另一个窗口调用 GetDlgItem（）：

The GetDlgItem() function retrieves a pointer to the specified control or child window inside the window for that the function has been called. You are calling this function from the child_1 window with an ID that does not exist in this window and the function will return NULL. To get the pointer to a control in another window, you must call GetDlgItem() for that other window:

m_View = (CEdit *) child_2->GetDlgItem(CE_Child2);

[更新：详细解决方案]

[UPDATE: Detailed solution]

// child1.h
class child_2; // Forward declaration to avoid including child_2.h

class child_1
{
// ...
public:
    void SetChild2(child_2 *p) { m_child2 = p; }
protected:
    child_2 *m_child2;
}

// child1.cpp
#include <child_2.h>

child_1::child_1(void)
{
    m_child_2 = NULL;
}

void child_1::OnBnClickedEnter()
{
    // Check if SetChild2() has been called and the window is valid.
    ASSERT(m_child2 && ::IsWindow(m_child2->m_hWnd));
    m_View = (CEdit *) m_child2->GetDlgItem(CE_Child2);
}

在child_1和child_2的父对话框的 OnInitDialog（）中调用 SetChild2（） function。

From within OnInitDialog() of the parent dialog of child_1 and child_2 call the SetChild2() function.

在一个子窗口中，您只能访问属于该窗口的控件。

您得到的错误是因为你试图访问属于另一个孩子的控件。



完成你需要的一个好方法是从child1向父母发送一条消息，以便父级可以从child1检索编辑控件值，并使用子窗口中的方法将其设置为child2。

In one child window, you can only access controls that belong to that window.
The error you're getting is because you're trying to access a control that belongs to another child.

A good way to accomplish what you need would be to send a message from child1 to the parent, so that the parent can then retrieve the edit control value from child1 and set it to child2 using methods in the child windows.

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