如何在按下另一个按钮时创建一个按钮并隐藏另一个按钮 [英] How to create a button when another button is pressed and hide the other one

问题描述

(问题在底部)

我正在尝试编写一个只有一个按钮的程序.如果按下这个按钮，它应该创建一个新按钮，并删除另一个，你会在这里看到:

I am trying to write a program, which has one button. If this button is pressed, it should create a new button, and delete the other one, you will see here:

constexpr unsigned int button1=111;
constexpr unsigned int button2=112;
bool buttonIsPressed = false;

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    static RECT    rect;
    PAINTSTRUCT ps;
    HDC hdc;

    switch (message)
    {
    case WM_CREATE:
    {
        GetClientRect(hWnd, &rect);

        CreateWindowEx(NULL,
                L"BUTTON",
              L"create new button",
              WS_TABSTOP | WS_VISIBLE |
              WS_CHILD | BS_DEFPUSHBUTTON,
              /*windowWidth-15,*/
              400,
              rect.bottom - 40,
              100,
              28,
              hWnd,
              (HMENU)button1,
              GetModuleHandle(NULL),
              NULL);

        
        if (buttonIsPressed == true)
        {
        
            CreateWindowEx(NULL,
                L"BUTTON",
              L"Text of the button",
              WS_TABSTOP | WS_VISIBLE |
              WS_CHILD | BS_DEFPUSHBUTTON,
              /*windowWidth-15,*/
              400,
              rect.bottom - 40,
              100,
              28,
              hWnd,
              (HMENU)button2,
              GetModuleHandle(NULL),
              NULL);

        }

    }
    case WM_PAINT:
    {
       
        return 0;
    }
    
    
    case WM_DESTROY:
    {
        PostQuitMessage(0);
        return 0;
    }
    case WM_COMMAND:
    {
        switch (LOWORD(wParam))
        {
        case button1:
        {
            buttonIsPressed = true;
            break;
        }
        }
        break;    
    }

    return DefWindowProc(hWnd, message, wParam, lParam);
}

我也尝试使用 UpdateWindow 和 InvalidateRect.

I also tried to use UpdateWindow and InvalidateRect.

问题 1:如何在按下另一个按钮时创建一个新按钮?

Question 1: How can i create a new button when the other button is pressed?

问题 2: 我怎样才能停止绘制另一个按钮.如果我使用 InvalidateRect，按钮会变得不可见，但只要我按下窗口，它就会再次可见.

Question 2: How can i stop drawing the other button. If I use InvalidateRect, the button becomes invisible, but as soon as i press on the window, it is visible again.

感谢您的关注和您的时间.

推荐答案

你已经接近了.您已经知道创建单个按钮 (CreateWindowEx()).在您显示的代码中，您只需将 WM_CREATE 处理程序中的第二个 CreateWindowEx() 移动到 WM_COMMAND 处理程序中，确保检查报告的 ID/HWND 以确保它是您感兴趣的第一个按钮，然后您可以根据需要 ShowWindow()/DestroyWindow() 该按钮并创建新按钮，例如:

You are close. You already know to create individual buttons (CreateWindowEx()). In the code you have shown, you just need to move the 2nd CreateWindowEx() from the WM_CREATE handler into the WM_COMMAND handler, being sure to check the reported ID/HWND to make sure it is the 1st button you are interested in, and then you can ShowWindow()/DestroyWindow() that button as needed and create the new button, eg:

constexpr unsigned int button1=111;
constexpr unsigned int button2=112;

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
    static RECT rect;
    //...

    switch (message)
    {
        case WM_CREATE:
        {
            GetClientRect(hWnd, &rect);

            CreateWindowEx(NULL,
                L"BUTTON",
                L"create new button",
                WS_TABSTOP | WS_VISIBLE |
                WS_CHILD | BS_DEFPUSHBUTTON,
                /*windowWidth-15,*/
                400,
                rect.bottom - 40,
                100,
                28,
                hWnd,
                (HMENU)button1,
                GetModuleHandle(NULL),
                NULL);

            break;
        }

        //...

        case WM_COMMAND:
        {
            if (HIWORD(wParam) == BN_CLICKED)
            {
                switch (LOWORD(wParam))
                {
                    case button1:
                    {
                        HWND hwndBtn = (HWND)lParam;
                        // use ShowWindow(hwndBtn, SW_HIDE) or DestroyWindow(hwndBtn) as needed... 

                        GetClientRect(hWnd, &rect);

                        CreateWindowEx(NULL,
                            L"BUTTON",
                            L"Text of the button",
                            WS_TABSTOP | WS_VISIBLE |
                            WS_CHILD | BS_DEFPUSHBUTTON,
                            /*windowWidth-15,*/
                            400,
                            rect.bottom - 40,
                            100,
                            28,
                            hWnd,
                            (HMENU)button2,
                            GetModuleHandle(NULL),
                            NULL);

                        break;
                    }

                    case button2:
                    {
                        //...
                        break;
                    }
                }

                return 0;
            }

            break;    
        }
    }

    return DefWindowProc(hWnd, message, wParam, lParam);
}

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