Qt在动态库中创建窗口

Qt在动态库中创建窗口,代码

首先创建dll项目

#ifndef EXPORTWIDGET_H
#define EXPORTWIDGET_H

#include <QtCore/qglobal.h>

#if defined(EXPORTWIDGET_LIBRARY)
#  define EXPORTWIDGETSHARED_EXPORT Q_DECL_EXPORT
#else
#  define EXPORTWIDGETSHARED_EXPORT Q_DECL_IMPORT
#endif

namespace ExportWidget
{
    extern "C"
    {
        EXPORTWIDGETSHARED_EXPORT void Init();

        EXPORTWIDGETSHARED_EXPORT void ShowWidget();

        EXPORTWIDGETSHARED_EXPORT void unInit();
    }
}

#endif // EXPORTWIDGET_H

实现

#include "exportwidget.h"
#include "form.h"

#include <QApplication>
#include <QDebug>

static QApplication* _Application;

EXPORTWIDGETSHARED_EXPORT void ExportWidget::Init()
{
    _Application = NULL;
}


EXPORTWIDGETSHARED_EXPORT void ExportWidget::ShowWidget()
{
    if(_Application == NULL)
    {
        int argc = 0;
        _Application = new QApplication(argc, NULL);
        // Form为普通widget窗口
		Form* _fm = new Form();
        _fm->show();
        _Application->exec();
    }
}

EXPORTWIDGETSHARED_EXPORT void ExportWidget::unInit()
{
    if(_Application != NULL)
    {
        _Application->quit();
        _Application = NULL;
    }
}

.pro文件

#-------------------------------------------------
#
# Project created by QtCreator 2022-11-24T14:36:38
#
#-------------------------------------------------

QT       += widgets core gui

TARGET = ExportWidget
TEMPLATE = lib

CONFIG += plugin c++11

DESTDIR = $$PWD/../Debug

DEFINES += EXPORTWIDGET_LIBRARY

# You can also make your code fail to compile if you use deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0

SOURCES += \
        exportwidget.cpp \
    form.cpp

HEADERS += \
        exportwidget.h \
    form.h

unix {
    target.path = /usr/lib
    INSTALLS += target
}

FORMS += \
    form.ui

使用

#include "exportwidget.h"

int main(int argc, char *argv[])
{
    for(int i = 0; i < 5; i++)
    {
        ExportWidget::Init();
        ExportWidget::ShowWidget();
        ExportWidget::unInit();
    }
    return 0;
}

注意

	// 如果为qt项目.pro文件

QT -= gui
QT += widgets

CONFIG += c++11 console
CONFIG -= app_bundle
DESTDIR = $$PWD/../Debug

TARGET = TestWidget

# The following define makes your compiler emit warnings if you use
# any feature of Qt which as been marked deprecated (the exact warnings
# depend on your compiler). Please consult the documentation of the
# deprecated API in order to know how to port your code away from it.
DEFINES += QT_DEPRECATED_WARNINGS

# You can also make your code fail to compile if you use deprecated APIs.
# In order to do so, uncomment the following line.
# You can also select to disable deprecated APIs only up to a certain version of Qt.
#DEFINES += QT_DISABLE_DEPRECATED_BEFORE=0x060000    # disables all the APIs deprecated before Qt 6.0.0

SOURCES += main.cpp


LIBS += -L$$PWD/../Debug/ -lExportWidget

QMAKE_LFLAGS += -Wl,-rpath=.

HEADERS += \
    exportwidget.h

赏

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