Qt的一个无边界窗口公共类

头文件：

#pragma once
#include 

class CFrameLessWidgetBase :
    public QWidget
{
public:
    CFrameLessWidgetBase(QWidget* p = nullptr);
    ~CFrameLessWidgetBase() {}

protected:
    bool nativeEvent(const QByteArray& eventType, void* message, long* result) override;

private:
    int m_nBorderWidth = 5;
};

实现：

#include "CFrameLessWidgetBase.h"
#include 
#include 
#include 

#pragma comment(lib, "user32.lib")
#pragma comment(lib,"dwmapi.lib")

CFrameLessWidgetBase::CFrameLessWidgetBase(QWidget* p)
	:QWidget(p)
{
	this->setWindowFlags(Qt::FramelessWindowHint | Qt::WindowMinMaxButtonsHint);
	setAttribute(Qt::WA_Hover);   //很重要
}

bool CFrameLessWidgetBase::nativeEvent(const QByteArray& eventType, void* message, long* result)
{
	MSG* param = static_cast(message);

	switch (param->message)
	{
	case WM_NCHITTEST:
	{
		int nX = GET_X_LPARAM(param->lParam) - this->geometry().x();
		int nY = GET_Y_LPARAM(param->lParam) - this->geometry().y();

		/*if (childAt(nX, nY) != nullptr)
			return QWidget::nativeEvent(eventType, message, result);*/

		if (nX > m_nBorderWidth && nX < this->width() - m_nBorderWidth &&
			nY > m_nBorderWidth && nY < this->height() - m_nBorderWidth)
		{
			if (childAt(nX, nY) != nullptr)
				return QWidget::nativeEvent(eventType, message, result);
		}

		if ((nX > 0) && (nX < m_nBorderWidth))
			*result = HTLEFT;

		if ((nX > this->width() - m_nBorderWidth) && (nX < this->width()))
			*result = HTRIGHT;

		if ((nY > 0) && (nY < m_nBorderWidth))
			*result = HTTOP;

		if ((nY > this->height() - m_nBorderWidth) && (nY < this->height()))
			*result = HTBOTTOM;

		if ((nX > 0) && (nX < m_nBorderWidth) && (nY > 0)
			&& (nY < m_nBorderWidth))
			*result = HTTOPLEFT;

		if ((nX > this->width() - m_nBorderWidth) && (nX < this->width())
			&& (nY > 0) && (nY < m_nBorderWidth))
			*result = HTTOPRIGHT;

		if ((nX > 0) && (nX < m_nBorderWidth)
			&& (nY > this->height() - m_nBorderWidth) && (nY < this->height()))
			*result = HTBOTTOMLEFT;

		if ((nX > this->width() - m_nBorderWidth) && (nX < this->width())
			&& (nY > this->height() - m_nBorderWidth) && (nY < this->height()))
			*result = HTBOTTOMRIGHT;

		return true;
	}
	}

	return false;
}

要实现无边界窗口的设计，只需要集成自这个类就可以了。