目标功能：

(1)按下btn，弹出绿色页面。

 (2)按下btn2,绿色页面隐藏。

 (3)按下左边余下的区域，绿色页面也隐藏。

(4)平滑地显示和隐藏

效果：

 

 form.h

#ifndef FORM_H
#define FORM_H#include <QWidget>namespace Ui {
class Form;
}class Form : public QWidget
{Q_OBJECTpublic:explicit Form(QWidget *parent = nullptr);~Form();private slots:void on_pushButton_clicked();private:Ui::Form *ui;
signals:void begin_move();
};#endif // FORM_H

 form.cpp

#include "form.h"
#include "ui_form.h"Form::Form(QWidget *parent) :QWidget(parent),ui(new Ui::Form)
{ui->setupUi(this);
}Form::~Form()
{delete ui;
}void Form::on_pushButton_clicked()
{emit begin_move();
}

 widget.h

#ifndef WIDGET_H
#define WIDGET_H#include <QWidget>
#include "form.h"
#include <QPropertyAnimation>
#include <QMouseEvent>
QT_BEGIN_NAMESPACE
namespace Ui { class Widget; }
QT_END_NAMESPACEclass Widget : public QWidget
{Q_OBJECTpublic:Widget(QWidget *parent = nullptr);~Widget();
protected:void mousePressEvent(QMouseEvent *event) override;bool eventFilter(QObject *obj,QEvent *event) override;
private slots:void on_pushButton_clicked();
private:Ui::Widget *ui;Form *f;QPropertyAnimation *animation,*animation1;bool flag;bool isShow;
};
#endif // WIDGET_H

widget.cpp 

#include "widget.h"
#include "ui_widget.h"
#include <QDebug>
#include <QEvent>#pragma execution_character_set("utf-8")
Widget::Widget(QWidget *parent): QWidget(parent), ui(new Ui::Widget)
{ui->setupUi(this);f=new Form(this);f->hide();flag=1;isShow=0;ui->pushButton_2->installEventFilter(this);connect(f,&Form::begin_move,this,[=](){if(isShow == 1){animation1->start();isShow=0;}});
}Widget::~Widget()
{delete ui;
}void Widget::mousePressEvent(QMouseEvent *event)
{if(event->button()==Qt::LeftButton){qDebug()<<"按下了鼠标左键";qDebug()<<event->pos();if(isShow == 1){animation1->start();isShow=0;}}
}bool Widget::eventFilter(QObject *obj, QEvent *event)
{if(obj==ui->pushButton_2){if(event->type() == QEvent::MouseButtonPress){qDebug()<<"按下按钮";QMouseEvent * me =static_cast<QMouseEvent *>(event);if(me->button() & Qt::LeftButton){qDebug()<<"按下左键";if(isShow == 1){animation1->start();isShow=0;}}return false;}}return QWidget::eventFilter(obj,event);
}void Widget::on_pushButton_clicked()
{if(flag==1){flag=0;f->resize(300,height());f->move(width(),0);f->show();animation = new QPropertyAnimation(f,"pos");animation->setDuration(1000);  //设置动画完成的时间长度animation->setStartValue(QPoint(width(),0)); //设置动画的开始值animation->setEndValue(QPoint(width()-f->width(),0)); //设置动画的结束值animation1 = new QPropertyAnimation(f,"pos");animation1->setDuration(1000);  //设置动画完成的时间长度animation1->setStartValue(QPoint(width()-f->width(),0)); //设置动画的开始值animation1->setEndValue(QPoint(width(),0)); //设置动画的结束值}animation->start(); //启动动画isShow=1;
}