无边框窗口

/**
 * 自定义无边框窗体、对话框和提示框
 *
 * MainWindow.h
 * 测试用例主要窗口
 *
 */

#include <QLabel>
#include <QDebug>
#include "MainWindow.h"
#include "ui_MainWindow.h"
#include "ui_AeroClientWidget.h"
#include "MuWinWindow.h"

MainWindow::MainWindow(QWidget *parent)
    : MuCustomWindow(parent)
    , ui(new Ui::MainWindow)
    , aeroUI(new Ui::AeroCLientWidget)
{
    setWindowTitle("Test Custom Window");
    resize(800, 600);

    QWidget *pClientWidget = new QWidget(this);
    ui->setupUi(pClientWidget);

    this->titleBar()->setTitleHeight(50);
    this->titleBar()->setObjectName("titleBar");
    this->titleBar()->titleLabel()->setObjectName("titleLabel");
    this->titleBar()->minimizeButton()->setObjectName("minimizeButton");
    this->titleBar()->maximizeButton()->setObjectName("maximizeButton");
    this->titleBar()->closeButton()->setObjectName("closeButton");

    // 设置中心客户区域
    setClientWidget(pClientWidget);

    // 设置messagebox的按钮样式表和标题样式表
    const QString buttonStyle = "QPushButton {  \
                                    border: none; \
                                    background-color: #52baff; \
                                    width: 80px; \
                                    height: 30px; \
                                 } \
                                 QPushButton::pressed { \
                                    background-color: gray; \
                                 }";
    MuCustomMessageBox::setTitleStyleSheet(QStringLiteral("QLabel { color: black }"));
    MuCustomMessageBox::setButtonStyleSheet(QDialogButtonBox::Ok, buttonStyle);
    connect(ui->dialogBtn, &QPushButton::clicked, this, &MainWindow::onDialogBtnClicked);
    connect(ui->informationBtn, &QPushButton::clicked, this, &MainWindow::onInformationBtnClicked);
    connect(ui->errorBtn, &QPushButton::clicked, this, &MainWindow::onErrorBtnClicked);
    connect(ui->successBtn, &QPushButton::clicked, this, &MainWindow::onSuccessBtnClicked);
    connect(ui->warningBtn, &QPushButton::clicked, this, &MainWindow::onWarningBtnClicked);
#ifdef Q_OS_WIN32
    initAreoWindow();
    connect(ui->aeroBtn, &QPushButton::clicked, m_AeroWindow, &MuWinAeroShadowWindow::show);
    connect(ui->winWindowBtn, &QPushButton::clicked, this, &MainWindow::onWinWindow);
#else
    ui->aeroBtn->hide();
#endif
}

MainWindow::~MainWindow()
{
    delete ui;
#ifdef Q_OS_WIN32
    delete m_AeroWindow;
#endif
}

void MainWindow::onDialogBtnClicked()
{
    MuCustomDialog dialog;
    QLabel label("This is a Custom Dialog!");
    label.setAlignment(Qt::AlignHCenter | Qt::AlignVCenter);
    dialog.titleBar()->titleLabel()->setObjectName("dialogTitleLabel");
    dialog.setModal(true);
    dialog.setWindowTitle("dialog");
    dialog.setClientWidget(&label);
    dialog.exec();
}

void MainWindow::onInformationBtnClicked()
{
    MuCustomMessageBox::showInformation(nullptr,
                                        QStringLiteral("Information!"),
                                        QStringLiteral("This is a Information MessageBox!"));
}

void MainWindow::onErrorBtnClicked()
{
    MuCustomMessageBox::showError(nullptr,
                                  QStringLiteral("Error!"),
                                  QStringLiteral("This is a Error MessageBox!"));
}

void MainWindow::onSuccessBtnClicked()
{
    MuCustomMessageBox::showSuccess(nullptr,
                                    QStringLiteral("Success!"),
                                    QStringLiteral("This is a Success MessageBox!"));
}

void MainWindow::onWarningBtnClicked()
{
    MuCustomMessageBox::showWarning(nullptr,
                                    QStringLiteral("Warning!"),
                                    QStringLiteral("This is a Warning MessageBox!"));
}

#ifdef Q_OS_WIN32
void MainWindow::initAreoWindow()
{
    m_AeroWindow = new MuWinAeroShadowWindow;
    m_AeroWindow->setRubberBandOnMove(true);
    m_AeroWindow->setRubberBandOnResize(true);
    m_AeroWindow->setWindowTitle(QStringLiteral("Test Aero Window"));
    m_AeroWindow->titleBar()->setObjectName("aeroTitleBar");
    QWidget *pClientWidget = new QWidget(m_AeroWindow);
    aeroUI->setupUi(pClientWidget);
    m_AeroWindow->setClientWidget(pClientWidget);
}
#endif

void MainWindow::onWinWindow()
{
    MuWinWindow *window = new MuWinWindow;
    window->resize(800, 600);
    window->show();
}

目标：
1、去除边框
2、窗口的上面部分实现拖动

实现：
1、设置无边框
w.setWindowFlags(Qt::FramelessWindowHint);
2、拖动窗口
mousePressEvent(QMouseEvent *e) //重写鼠标点击事件，为了获取开始点击的坐标
mouseMoveEvent(QMouseEvent *e) //重写移动事件

#ifndef MAINWINDOW_H
#define MAINWINDOW_H
#include <QMainWindow>
#include <QMouseEvent>
#include <windows.h>        //注意头文件
#include <windowsx.h>

QT_BEGIN_NAMESPACE
namespace Ui { class MainWindow; }
QT_END_NAMESPACE
class MainWindow : public QMainWindow
{
    Q_OBJECT
public:
    MainWindow(QWidget *parent = nullptr);
    ~MainWindow();
private:
    Ui::MainWindow *ui;
protected:
    void mousePressEvent(QMouseEvent *e);
    void mouseMoveEvent(QMouseEvent *e);
private:
    int boundaryWidth;
    QPoint clickPos;
};
#endif // MAINWINDOW_H

void MainWindow::mousePressEvent(QMouseEvent *e)
{
    if(e->button()==Qt::LeftButton)
        clickPos=e->pos();
}
void MainWindow::mouseMoveEvent(QMouseEvent *e)
{
    if(e->buttons()&Qt::LeftButton  //左键点击并且移动
            && e->pos().x()>=0      //范围在窗口的上面部分
            && e->pos().y()>=0
            && e->pos().x()<= geometry().width()
            && e->pos().y() <= geometry().height()/10)
    {
        move(e->pos()+pos()-clickPos);  //移动窗口
    }
}

主要参考了https://blog.csdn.net/qq_16952303/article/details/51974502?locationNum=8&fps=1，但原文章在某些情况下，鼠标形状不刷新，改进了一版。

MyResizeWidget.h

#ifndef MYRESIZEWIDGET_H
#define MYRESIZEWIDGET_H

#include <QtGui>

#define EDGE_MARGIN 8
namespace Ui {
class MyResizeWidget;
}

class MyResizeWidget : public QWidget
{
    Q_OBJECT
    
public:
    explicit MyResizeWidget(QWidget *parent = 0);
protected:
	virtual void mouseMoveEvent(QMouseEvent * event);
	virtual void mousePressEvent(QMouseEvent * event);
	virtual void mouseReleaseEvent(QMouseEvent * event);
	virtual void enterEvent(QEvent * event);
	virtual void leaveEvent(QEvent * event);
private:
	QPoint dragPosition;   //鼠标拖动的位置
	enum {nodir,
		top = 0x01,
		bottom = 0x02,
		left = 0x04,
		right = 0x08,
		topLeft = 0x01 | 0x04,
		topRight = 0x01 | 0x08,
		bottomLeft = 0x02 | 0x04,
		bottomRight = 0x02 | 0x08
	} resizeDir; //更改尺寸的方向

private:
	void testEdge(QMouseEvent *event);  //检测鼠标是否接近窗口边缘
};

#endif // SEARCHWIDGET_H

MyResizeWidget.cpp

#include "MyResizeWidget.h"

#define min(a,b) ((a)<(b)? (a) :(b))
#define max(a,b) ((a)>(b)? (a) :(b))

MyResizeWidget::MyResizeWidget(QWidget *parent)
: QWidget(parent)
{
	resizeDir = nodir;   //初始化检测方向为无
	setWindowFlags(Qt::FramelessWindowHint);  //设置无边框
	setMouseTracking(true); //开启鼠标追踪
	setMinimumSize(90, 200);
}

void MyResizeWidget::mousePressEvent(QMouseEvent * event)
{
	if (event->button() == Qt::LeftButton)  //每当按下鼠标左键就记录一下位置
	{
		dragPosition = event->globalPos() - frameGeometry().topLeft();  //获得鼠标按键位置相对窗口左上面的位置
	}


}

void MyResizeWidget::testEdge(QMouseEvent *event)
{
	int diffLeft = event->globalPos().x() - frameGeometry().left();      //计算鼠标距离窗口上下左右有多少距离
	int diffRight = event->globalPos().x() - frameGeometry().right();
	int diffTop = event->globalPos().y() - frameGeometry().top();
	int diffBottom = event->globalPos().y() - frameGeometry().bottom();

	Qt::CursorShape cursorShape;
	
	if(diffTop < EDGE_MARGIN && diffTop>=0){                              //根据 边缘距离 分类改变尺寸的方向
		if(diffLeft < EDGE_MARGIN && diffLeft>=0){
			resizeDir = topLeft;
			cursorShape = Qt::SizeFDiagCursor;
		}
		else if(diffRight > -EDGE_MARGIN && diffRight<=0){
			resizeDir = topRight;
			cursorShape = Qt::SizeBDiagCursor;
		}
		else{
			resizeDir = top;
			cursorShape = Qt::SizeVerCursor;
		}
	}
	else if(abs(diffBottom) < EDGE_MARGIN && diffBottom<=0){
		if(diffLeft < EDGE_MARGIN && diffLeft>=0){
			resizeDir = bottomLeft;
			cursorShape = Qt::SizeBDiagCursor;
		}
		else if(diffRight > -EDGE_MARGIN && diffRight<=0){
			resizeDir = bottomRight;
			cursorShape = Qt::SizeFDiagCursor;
		}
		else{
			resizeDir = bottom;
			cursorShape = Qt::SizeVerCursor;
		}
	}
	else if(abs(diffLeft) < EDGE_MARGIN){
		resizeDir = left;
		cursorShape = Qt::SizeHorCursor;
	}
	else if(abs(diffRight) < EDGE_MARGIN){
		resizeDir = right;
		cursorShape = Qt::SizeHorCursor;
	}
	else{
		resizeDir = nodir;
		cursorShape = Qt::ArrowCursor;
	}

	QApplication::setOverrideCursor(cursorShape);
}

void MyResizeWidget::mouseMoveEvent(QMouseEvent * event)
{
	if (event->buttons() & Qt::LeftButton){                 //如果左键是按下的
		if(resizeDir == nodir){                             //如果鼠标不是放在边缘那么说明这是在拖动窗口
			move(event->globalPos() - dragPosition);
		}
		else{
			int ptop,pbottom,pleft,pright;                   //窗口上下左右的值
			ptop = frameGeometry().top();
			pbottom = frameGeometry().bottom();
			pleft = frameGeometry().left();
			pright = frameGeometry().right();
			if(resizeDir & top){                               //检测更改尺寸方向中包含的上下左右分量
				if(height() == minimumHeight()){
					ptop = min(event->globalY(),ptop);
				}
				else if(height() == maximumHeight()){
					ptop = max(event->globalY(),ptop);
				}
				else{
					ptop = event->globalY();
				}
			}
			else if(resizeDir & bottom){
				if(height() == minimumHeight()){
					pbottom = max(event->globalY(),ptop);
				}
				else if(height() == maximumHeight()){
					pbottom = min(event->globalY(),ptop);
				}
				else{
					pbottom = event->globalY();
				}
			}

			if(resizeDir & left){                        //检测左右分量
				if(width() == minimumWidth()){
					pleft = min(event->globalX(),pleft);
				}
				else if(width() == maximumWidth()){
					pleft = max(event->globalX(),pleft);
				}
				else{
					pleft = event->globalX();
				}
			}
			else if(resizeDir & right){
				if(width() == minimumWidth()){
					pright = max(event->globalX(),pright);
				}
				else if(width() == maximumWidth()){
					pright = min(event->globalX(),pright);
				}
				else{
					pright = event->globalX();
				}
			}
			setGeometry(QRect(QPoint(pleft,ptop),QPoint(pright,pbottom)));
		}
	}
	else testEdge(event);   //当不拖动窗口、不改变窗口大小尺寸的时候  检测鼠标边缘


}
void MyResizeWidget::mouseReleaseEvent(QMouseEvent *event)
{
	if(resizeDir != nodir){         //还原鼠标样式
		testEdge(event);
	}
}

void MyResizeWidget::enterEvent(QEvent * event)
{
	QWidget::enterEvent(event);
}

void MyResizeWidget::leaveEvent(QEvent * event)
{
	QApplication::setOverrideCursor(Qt::IBeamCursor);
	QWidget::leaveEvent(event);
}