子类按钮不会在每次重复点击时产生动画

Subclassed button not producing animation on every repeated click

我在 WindowProc 回调的 WM_CREATE 消息中创建了一个自定义子 classed 按钮。下面是创建和 subclassing 指令,以及用于控制按钮状态的结构:

static button_state btnstateBtnInstall;
hBtnInstall = CreateWindow(WC_BUTTON, L"Button", WS_CHILD | WS_VISIBLE, (window_width / 2) - (btn_install_width / 2), window_height - (window_height / 6) - (btn_install_height / 2), btn_install_width, btn_install_height, hwnd, (HMENU)HMENU_btn_install, NULL, NULL);
SetWindowSubclass(hBtnInstall, BtnInstallProc, 0, (DWORD_PTR)&btnstateBtnInstall);

结构定义如下:

struct button_state
{
    bool pushed;
    button_state() { pushed = false; }
};

subclassed过程编码如下:

LRESULT CALLBACK BtnInstallProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam, UINT_PTR uIdSubClass, DWORD_PTR dwRefData)
{
    button_state* state = (button_state*)dwRefData;

    // Omitted part where I create brushes and font to be used for painting

    switch (msg)
    {
    case WM_PAINT:
    {
        PAINTSTRUCT ps;
        HDC hdc = BeginPaint(hwnd, &ps);
        RECT rc = ps.rcPaint;

        POINT pt;
        GetCursorPos(&pt);
        ScreenToClient(hwnd, &pt);
        BOOL hover = PtInRect(&rc, pt);

        if (state->pushed)
        {
            // Pushed
            FillRect(hdc, &rc, hBrPushed);
        }
        else if (hover)
        {
            // Mouse over
            FillRect(hdc, &rc, hBrHover);
        }
        else
        {
            // Normal
            FillRect(hdc, &rc, hBrNormal);
        }

        SetBkMode(hdc, TRANSPARENT);
        SetTextColor(hdc, RGB(255, 255, 255));
        SelectFont(hdc, SegoeUI);
        static LPCWSTR InstallBtnTxt = L"Install";
        static int InstallBtnTxtLen = static_cast<int>(wcslen(InstallBtnTxt));  // Should be a safe cast, for small arrays like this one
        DrawText(hdc, InstallBtnTxt, InstallBtnTxtLen, &rc, DT_SINGLELINE | DT_CENTER | DT_VCENTER);

        EndPaint(hwnd, &ps);
        return 0;
    }

    case WM_LBUTTONDOWN:
    {
        state->pushed = true;

        break;
    }

    case WM_LBUTTONUP:
    {
        state->pushed = false;

        break;
    }

    // Omitted part where I handle WM_DESTROY to do cleanup

    }

    return DefSubclassProc(hwnd, msg, wParam, lParam);
}

为了将我的按钮的行为与标准按钮的行为进行比较,我创建了另一个没有子classing 并且仅使用标准 BUTTON class 和 WS_VISIBLE | WS_CHILD 的按钮属性。

正如您从附加的 gif 中看到的那样,当我 重复单击标准 class 按钮时,每次单击都会产生动画 而当多次单击时 我用这段代码创建的按钮似乎并没有捕捉到每一次点击,但(如您所见)大约有 50%

我错过了什么?为什么我的按钮不像标准按钮那样灵敏 class?

TL;DR: 当慢慢点击我的子classed 按钮时,绘画是正确的。正如您从我的附图中看到的那样,重复点击它们时,我的按钮和标准按钮之间的区别很大。我怎样才能让我的控件像标准控件一样响应迅速?

当您快速点击时,某些 WM_LBUTTONDOWN 消息会被 WM_LBUTTONDBLCLK 取代(默认双击处理)。您需要像处理 WM_LBUTTONDOWN 消息一样处理它。

case WM_LBUTTONDOWN:
case WM_LBUTTONDBLCLK: // <-- Added
{
    state->pushed = true;

    break;
}