QT 正确删除Layout-Toy模板网

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前言：QT中以代码的方式设置布局的函数是 *void QWidget::setLayout(QLayout *layout)*但是没有提供直接删除布局的函数。在删除布局时应该注意内存泄漏的问题。下面的方法仅供参考。

    QLayoutItem *item;
    if(this->layout() != nullptr)
    {
        while((item = this->layout()->takeAt(0)) != nullptr)
        {
            delete item->widget();
            delete item;
        }
        delete this->layout();
    }

参考文档takeat函数
以下是主要工程代码
widget.cpp

#include "widget.h"
#include "ui_widget.h"
#include "mypushbutton.h"
#include <QVBoxLayout>

Widget::Widget(QWidget *parent) :
    QWidget(parent),
    ui(new Ui::Widget)
{
    ui->setupUi(this);
    sonWidget = new QWidget;
    QPushButton *sonButton = new QPushButton(sonWidget);
    sonWidget->hide();
    myPushButton *button1 = new myPushButton;
    button1->setText(QStringLiteral("按钮1"));
    connect(button1, &QPushButton::clicked, this, [=](){
        qDebug() << QStringLiteral("按钮1被点击");
    });
    myPushButton *button2 = new myPushButton;
    button2->setText(QStringLiteral("按钮2"));
    QVBoxLayout *box = new QVBoxLayout;
    box->addWidget(button1);
    box->addWidget(button2);
    this->setLayout(box);
    connect(button2, &QPushButton::clicked, this, [=](){
        sonWidget->show();
    });
    connect(sonButton, &QPushButton::clicked, this, &Widget::slot_sonButton);
}

Widget::~Widget()
{
    delete ui;
}

void Widget::slot_sonButton()
{
    QLayoutItem *item;
    if(this->layout() != nullptr)
    {
        while((item = this->layout()->takeAt(0)) != nullptr)
        {
            delete item->widget();
            delete item;
        }
        delete this->layout();
    }
    QHBoxLayout *box = new QHBoxLayout;
    myPushButton *button = new myPushButton;
    box->addWidget(button);
    this->setLayout(box);
}

widget.h

#ifndef WIDGET_H
#define WIDGET_H

#include <QWidget>

namespace Ui {
class Widget;
}

class Widget : public QWidget
{
    Q_OBJECT

public:
    explicit Widget(QWidget *parent = nullptr);
    ~Widget();

private slots:
    void slot_sonButton();

private:
    Ui::Widget *ui;
    QWidget *sonWidget;
};

#endif // WIDGET_H

mypushbutton.cpp文章来源地址https://www.toymoban.com/news/detail-640652.html

#include "mypushbutton.h"

myPushButton::myPushButton(QWidget *parent) : QPushButton(parent)
{

}

myPushButton::~myPushButton()
{
    qDebug() << QStringLiteral("按钮被析构");
}