I. Introduction

The goal of the universal mobile class is to support mouse dragging after placing any control, and dragging in the container or parent class. There are many application scenarios for this, such as devices placed on the map, which require the user to press and drag by themselves. Move to the designated appropriate location, then save the location coordinates of the device to the database, and load it directly next time it is opened. It is widely used in some security projects, power projects, environmental monitoring, etc. Sometimes the equipment corresponds to multiple types. What was done before The method is to directly encapsulate the mobile code in the custom control of the corresponding device. A huge disadvantage is that if a new control is added, repeated code needs to be added to the control. Can this function be independent? Just pass in the control, of course. For example, I have written many custom controls. Now I need the control to be placed in a container so that it can be dragged freely. I just need to create a new universal mobile class.
Project open source address: https://gitee.com/feiyangqingyun/QWidgetDemo

2. Functions implemented

1: You can specify the widget that needs to be moved
2: You can set whether to limit the left mouse button dragging
3: Support any widget control

3. Effect drawing

Insert image description here

4. Header file code

#ifndef MOVEWIDGET_H
#define MOVEWIDGET_H

/**
 * 通用控件移动类 作者:feiyangqingyun(QQ:517216493) 2019-9-28
 * 1:可以指定需要移动的widget
 * 2:可设置是否限定鼠标左键拖动
 * 3:支持任意widget控件
 */

#include <QWidget>

#ifdef quc
#if (QT_VERSION < QT_VERSION_CHECK(5,7,0))
#include <QtDesigner/QDesignerExportWidget>
#else
#include <QtUiPlugin/QDesignerExportWidget>
#endif

class QDESIGNER_WIDGET_EXPORT MoveWidget : public QObject
#else
class MoveWidget : public QObject
#endif

{
    Q_OBJECT
public:
    explicit MoveWidget(QObject *parent = 0);

protected:
    bool eventFilter(QObject *watched, QEvent *event);

private:
    QPoint lastPoint;   //最后按下的坐标
    bool pressed;       //鼠标是否按下
    bool leftButton;    //限定鼠标左键
    QWidget *widget;    //移动的控件

public Q_SLOTS:
    //设置是否限定鼠标左键
    void setLeftButton(bool leftButton);
    //设置要移动的控件
    void setWidget(QWidget *widget);
};

#endif // MOVEWIDGET_H

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5. Core code

#include "movewidget.h"
#include "qevent.h"
#include "qdebug.h"

MoveWidget::MoveWidget(QObject *parent) : QObject(parent)
{
    lastPoint = QPoint(0, 0);
    pressed = false;
    leftButton = true;
    widget = 0;
}

bool MoveWidget::eventFilter(QObject *watched, QEvent *event)
{
    if (widget != 0 && watched == widget) {
        QMouseEvent *mouseEvent = (QMouseEvent *)event;
        if (mouseEvent->type() == QEvent::MouseButtonPress) {
            //如果限定了只能鼠标左键拖动则判断当前是否是鼠标左键
            if (leftButton && mouseEvent->button() != Qt::LeftButton) {
                return false;
            }

            //判断控件的区域是否包含了当前鼠标的坐标
            if (widget->rect().contains(mouseEvent->pos())) {
                lastPoint = mouseEvent->pos();
                pressed = true;
            }
        } else if (mouseEvent->type() == QEvent::MouseMove && pressed) {
            //计算坐标偏移值,调用move函数移动过去
            int offsetX = mouseEvent->pos().x() - lastPoint.x();
            int offsetY = mouseEvent->pos().y() - lastPoint.y();
            widget->move(widget->x() + offsetX, widget->y() + offsetY);
        } else if (mouseEvent->type() == QEvent::MouseButtonRelease && pressed) {
            pressed = false;
        }
    }

    return QObject::eventFilter(watched, event);
}

void MoveWidget::setWidget(QWidget *widget)
{
    if (this->widget == 0) {
        this->widget = widget;
        this->widget->installEventFilter(this);
    }
}

void MoveWidget::setLeftButton(bool leftButton)
{
    this->leftButton = leftButton;
}

6. Control introduction

More than 150 exquisite controls, covering various dashboards, progress bars, progress balls, compasses, curves, rulers, thermometers, navigation bars, navigation bars, flatui, highlight buttons, sliding selectors, lunar calendar, etc. Far exceeds the number of controls integrated by qwt.
Each class can be independently formed into a separate control, with zero coupling. Each control has a header file and an implementation file, and does not rely on other files. It is convenient for a single control to be integrated into the project in the form of source code, with less code. The control classes of qwt are interlocking and highly coupled. If you want to use one of the controls, you must include all the code.
All written in pure Qt, drawn by QWidget+QPainter, supports any Qt version from Qt4.6 to Qt5.13, supports compilers such as mingw, msvc, gcc, etc., and supports any operating system such as windows+linux+mac+embedded linux, etc., without garbled code , can be directly integrated into Qt Creator and used like the built-in controls. Most effects only need to set a few properties, which is extremely convenient.
Each control has a corresponding separate DEMO containing the source code of the control for easy reference and use. It also provides an integrated DEMO used by all controls.
The source code of each control has detailed Chinese comments and is written in accordance with unified design specifications, making it easy to learn how to write custom controls.
The default color matching of each control and the color matching corresponding to the demo are very exquisite.
More than 130 visible controls and 6 invisible controls.
Some controls provide multiple style choices and multiple indicator style choices.
All controls adapt to form stretch changes.
Integrated custom control attribute designer, supports drag and drop design, WYSIWYG, supports import and export of xml format.
Comes with activex control demo, all controls can be run directly in the IE browser.
Integrate fontawesome graphic fonts + hundreds of graphic fonts collected by Alibaba iconfont, and enjoy the fun brought by graphic fonts.
All controls finally generate a dynamic library file (dll or so, etc.), which can be directly integrated into qtcreator for drag and drop design.
There is already a qml version, and a pyqt version will be considered later if there is great demand from users.
The custom control plug-in is open to dynamic library use (free forever), without any backdoors or restrictions, so please feel free to use it.
Currently, 26 versions of dll have been provided, including qt5.12.3 msvc2017 32+64 mingw 32+64.
Controls are added and improved from time to time, and the SDK is updated from time to time. Suggestions are welcome, thank you!
For introductory Qt books, we recommend Huo Yafei's "Quick Start with Qt Creator" and "Introduction to Qt5 Programming". For advanced Qt books, we recommend the official "C++ GUI Qt4 Programming".
I highly recommend the series of self-cultivation and planning books for programmers, "The Big Talk Programmer", "Programmer's Growth Course", and "The Worry-Relieving Programmer", which will benefit you a lot and will last a lifetime!
SDK address: https://gitee.com/feiyangqingyun/QUCSDK

Original link: https://www.cnblogs.com/feiyangqingyun/p/11608377.html