#ifndef MBASEWIDGET_H
#define MBASEWIDGET_H#include <QtWidgets/QWidget>
#include "windows.h"class MBaseWidget : public QWidget
{Q_OBJECTpublic:MBaseWidget(QWidget *parent);~MBaseWidget();void setMarginWidth(const int &);           //设置鼠标可以在界面边缘多大范围内拖动改变界面大小void serResizable(bool);                  //设置是否可以拖动改变大小protected:bool nativeEvent(const QByteArray & eventType, void * message, long * result);bool winEvent(MSG *message, long *result);private:int m_iMarginWidth;bool m_bCanResize;
};#endif // MBASEWIDGET_H

#include "MBaseWidget.h"
#include "windowsx.h"MBaseWidget::MBaseWidget(QWidget *parent): QWidget(parent)
{m_iMarginWidth = 3;m_bCanResize = true;setWindowFlags(Qt::FramelessWindowHint);
}MBaseWidget::~MBaseWidget()
{}void MBaseWidget::setMarginWidth(const int &iWidth)
{m_iMarginWidth = iWidth;
}void MBaseWidget::serResizable(bool bCanResize)
{m_bCanResize = bCanResize;
}//处理windows事件，在QT5中，被函数nativeEvent取代
bool MBaseWidget::winEvent(MSG *message, long *result)
{switch (message->message){case WM_NCHITTEST:int iPosX = GET_X_LPARAM(message->lParam) - this->frameGeometry().x();//鼠标位置xint iPosY = GET_Y_LPARAM(message->lParam) - this->frameGeometry().y();//鼠标位置y*result = HTCAPTION;if (!m_bCanResize){return true;//返回为真，此时仍可拖动，但无法改变大小}if (iPosX >= 0 && iPosX <= m_iMarginWidth){*result = HTLEFT;//左int iHeight = this->height();if (iPosY >= 0 && iPosY <= m_iMarginWidth){*result = HTTOPLEFT;//左上}if (iPosY >= iHeight - m_iMarginWidth && iPosY <= iHeight){*result = HTBOTTOMLEFT;//左下}return true;}int iWidth = this->width();int iHeight = this->height();if (iPosX >= iWidth - m_iMarginWidth && iPosX <= iWidth){*result = HTRIGHT;//右if (iPosY >= 0 && iPosY <= m_iMarginWidth){*result = HTTOPRIGHT;//右上return true;}if (iPosY >= iHeight - m_iMarginWidth && iPosY <= iHeight){*result = HTBOTTOMRIGHT;//右下return true;}return true;}if (iPosY >= 0 && iPosY <= m_iMarginWidth){*result = HTTOP;//上return true;}if (iPosY >= iHeight - m_iMarginWidth && iPosY <= iHeight){*result = HTBOTTOM;//下return true;}return true;}return false;
}bool MBaseWidget::nativeEvent(const QByteArray &eventType, void *message, long *result)
{return winEvent((MSG*)message, result);
}