多个QtWidget层叠显示，置顶，置底,Lbel显示图片

多个QtWidget层叠显示，置顶，置底,Lbel显示图片

把多个widget放入QStackedLayout
QStackedLayout设置成setStackingMode(QStackedLayout::StackAll);

解释:
enum QStackedLayout::StackingMode
This enum specifies how the layout handles its child widgets regarding their visibility. Constant Value Description
QStackedLayout::StackOne 0 Only the current widget is visible. This is the default.
QStackedLayout::StackAll 1 All widgets are visible. The current widget is merely raised.

/////.h

#ifndef MAINWINDOW_H

#define MAINWINDOW_H

#include 

#include "MCanvas.h"

class MainWindow : public QMainWindow

{

    Q_OBJECT

public:

    MainWindow(QWidget *parent = 0);

    ~MainWindow();

    MCanvas * canvs;

};

#endif // MAINWINDOW_H

////////.cpp

#include "MainWindow.h"

#include

#include 

MainWindow::MainWindow(QWidget *parent)

    : QMainWindow(parent)

{

setWindowTitle("canvastest");

    setWindowIcon(QIcon("F:\\media\Image\\3.jpg"));

    QWidget *CentralWidget = new QWidget(this);

    QString imagepath = "F:\\media\\Image\\3.jpg";

    QPixmap pixmap(imagepath);

    QPixmap scaledPixmap = pixmap.scaled(QSize(500,500),Qt::KeepAspectRatio);

    QLabel *lblResultImage = new QLabel(CentralWidget);

    lblResultImage->setPixmap(scaledPixmap);

    canvs = new MCanvas(CentralWidget);

    canvs->setPenColor(0,0,0,255);

    canvs->raise();

    canvs->setWindowFlags(Qt::WindowStaysOnTopHint);

    lblResultImage->setWindowFlags(Qt::WindowStaysOnBottomHint);

    QStackedLayout * sBoxLayout = new QStackedLayout();

    sBoxLayout->setStackingMode(QStackedLayout::StackAll);

    sBoxLayout->addWidget(lblResultImage);

    sBoxLayout->addWidget(canvs);

    CentralWidget->setLayout(sBoxLayout);

    this->setCentralWidget(CentralWidget);

    canvs->raise();

    canvs->setWindowFlags(Qt::WindowStaysOnTopHint);//置顶

    lblResultImage->setWindowFlags(Qt::WindowStaysOnBottomHint);//置底

//    lblResultImage->raise();

//    lblResultImage->setWindowFlags(Qt::WindowStaysOnTopHint);

//    canvs->setWindowFlags(Qt::WindowStaysOnBottomHint);

}

MainWindow::~MainWindow()

{

}