Qt+联想电脑管家

1.自定义按钮类

效果：

(1)仅当未选中，未悬浮时

 (2)其他三种情况，均如图

#ifndef BTN_H
#define BTN_H

#include 
class btn : public QPushButton
{
    Q_OBJECT
public:
    btn(QWidget * parent = nullptr);
    void set_normal_icon(QString icon);
    void set_checked_icon(QString icon);
    void init();
protected:
    void paintEvent(QPaintEvent *) override;
    void enterEvent(QEvent *event);
    void leaveEvent(QEvent *event);
private:
    QString normal_icon,checked_icon;
    //选中，悬浮
    bool hover;
};

#endif // BTN_H

#include "btn.h"
#include 
#include 
#pragma execution_character_set("utf-8")
btn::btn(QWidget * parent ): QPushButton(parent)
{
    //正常时，无边框
    //被选中时，背景变换+圆角矩形
    init();
}

void btn::set_normal_icon(QString icon)
{
    normal_icon=icon;
}

void btn::set_checked_icon(QString icon)
{
    checked_icon=icon;
}


void btn::init()
{
    QSizePolicy sizePolicy1(QSizePolicy::Fixed, QSizePolicy::Fixed);
    sizePolicy1.setHorizontalStretch(0);
    sizePolicy1.setVerticalStretch(0);
    sizePolicy1.setHeightForWidth(this->sizePolicy().hasHeightForWidth());
    this->setSizePolicy(sizePolicy1);
    //宽高
    this->setMinimumSize(QSize(75, 75));
    this->setMaximumSize(QSize(75, 75));
    //可选中
    this->setCheckable(true);

    hover=false;
}

void btn::enterEvent(QEvent *event)
{
    qDebug()<<"进入事件发生";
    hover=true;
}

void btn::leaveEvent(QEvent *event)
{
    qDebug()<<"离开事件发生";
    hover=false;
}

void btn::paintEvent(QPaintEvent *)
{
    QPainter painter(this);
    painter.setRenderHints(QPainter::Antialiasing | QPainter::SmoothPixmapTransform | QPainter::TextAntialiasing, true);
    if(!hover && !this->isChecked()){
        //画黑图标
        QPixmap pix(normal_icon);
        pix=pix.scaled(40,40,Qt::IgnoreAspectRatio);
        //75*75,40*40
        //(75-40)/2=12.5

        QRectF target(12.5, 12.5, 52.5, 52.5);
        QRectF source(0.0, 0.0, 40.0, 40.0);
        painter.drawPixmap(target,pix,source);
    }
    else{
        //画圆角矩形
        QRect rect(0,0,75,75);
        painter.setPen(Qt::NoPen);
        painter.setBrush(QBrush(QColor(255,255,255)));
        painter.drawRoundedRect(rect,10,10,Qt::AbsoluteSize);

        //画蓝图标
        QPixmap pix(checked_icon);
        pix=pix.scaled(40,40,Qt::IgnoreAspectRatio);
        //75*75,40*40
        //(75-40)/2=12.5

        QRectF target(12.5, 12.5, 52.5, 52.5);
        QRectF source(0.0, 0.0, 40.0, 40.0);
        painter.drawPixmap(target,pix,source);
    }
}

2.实验：

label与widget平级，label在widget上面，label显示完全

label在widget里面，label局部显示：

 

3.自定义按钮类2： 

效果：

#ifndef BTN2_H
#define BTN2_H

#include 
class btn2 : public QPushButton
{
    Q_OBJECT
public:
    btn2(QWidget * parent =nullptr);
    void get_icon(QString path);
protected:
    void paintEvent(QPaintEvent *) override;
private:
    QString icon;
};

#endif // BTN2_H

#include "btn2.h"
#include 
#include 
#pragma execution_character_set("utf-8")
btn2::btn2(QWidget *parent):
    QPushButton(parent)
{

}

void btn2::get_icon(QString path)
{
    icon=path;
}

void btn2::paintEvent(QPaintEvent *)
{
    QPainter painter(this);
    painter.setRenderHints(QPainter::Antialiasing | QPainter::SmoothPixmapTransform | QPainter::TextAntialiasing, true);

    //圆角边框
    QRect rect(0,0,200,75);
    QPen pen;
    pen.setColor(QColor(244,244,244));
    pen.setWidth(3);
    pen.setStyle(Qt::SolidLine);
    painter.setPen(pen);
    painter.setBrush(QBrush(QColor(255,255,255)));
    painter.drawRoundedRect(rect,10,10,Qt::AbsoluteSize);
    //蓝色图标
    QPixmap pix(icon);
    pix=pix.scaled(40,40,Qt::IgnoreAspectRatio);
    //75*75,40*40
    //(75-40)/2=12.5
    QRectF target(12.5, 12.5, 52.5, 52.5);
    QRectF source(0.0, 0.0, 40.0, 40.0);
    painter.drawPixmap(target,pix,source);

    //文字
    QFont font;
    font.setPointSize(12);
    font.setFamily("隶书");
    painter.setFont(font);
    painter.setPen(QColor(0,0,0));
    painter.drawText(52.5,0,200-52.5,75,Qt::AlignCenter,this->text());

}

4.实验：

目标：得到这个蓝色矩形左上角的坐标信息： 

pos : QPoint

它返回的是相对于父窗口的偏移位置，而不是最外面的窗口的。

 可以使用这个函数来实现目标功能：

QPoint Form::get_pos(QWidget * w)
{
    QWidget * p=qobject_cast(w->parent());
    if(p == this){
        return w->pos();
    }
    else{
        return w->pos()+get_pos(p);
    }
}

5.注意：在初始化函数中去获取目标位置信息，因为这时候都还没有布局好，得到的结果是错误的。

可用方法：

使用定时器延时一下

    timer.singleShot(100,this,[=](){
        //这样就可以解决输出为0的问题了
        for(int i=0;iset_absolute_pos(get_pos(one));
            qDebug()<get_absolute_pos();
        }
    });

6.问题：

 想实现这样的效果，但延迟比较大，该方案pass，想不出解决办法。

7.QButtonGroup的使用

    group=new QButtonGroup(this);
    for(int i=0;i(btn1.at(i));
        group->addButton(b,i+1);
    }

8.去边框

导入这两个文件movable_widget.h,movable_widget.cpp

#ifndef MOVABLE_WIDGET_H
#define MOVABLE_WIDGET_H

#include 

class movable_widget:public QWidget
{
public:
    movable_widget(QWidget * parent=0);
protected:
    void mouseMoveEvent(QMouseEvent *event);
    void mousePressEvent(QMouseEvent *event);
    void mouseReleaseEvent(QMouseEvent *event);
    void paintEvent(QPaintEvent *event);
private:
    QPoint Pos;
    bool ismoving;
};

#endif // MOVABLE_WIDGET_H

#include "movable_widget.h"
#include 
#include 
movable_widget::movable_widget(QWidget * parent):
    QWidget(parent)
{
    setWindowFlag(Qt::FramelessWindowHint);
    setAttribute(Qt::WA_TranslucentBackground);

}
void movable_widget::mouseMoveEvent(QMouseEvent *event)
{
    if(ismoving)
    {
        QPoint now=event->globalPos()-Pos;
        move(now);
    }
    QWidget::mouseMoveEvent(event);
}

void movable_widget::mousePressEvent(QMouseEvent *event)
{
    if(event->button()==Qt::LeftButton)
    {
            ismoving=true;
            Pos=event->globalPos()-pos();
    }
    QWidget::mousePressEvent(event);
}

void movable_widget::mouseReleaseEvent(QMouseEvent *event)
{
    ismoving=false;
    QWidget::mouseReleaseEvent(event);
}
void movable_widget::paintEvent(QPaintEvent *event)
{
    QPainter painter(this);
    painter.setRenderHint(QPainter::Antialiasing);	// 反锯齿;
    painter.setBrush(QBrush(Qt::red));
    painter.setPen(Qt::transparent);
    QRect rect = this->rect();
    rect.setWidth(rect.width() - 1);
    rect.setHeight(rect.height() - 1);
    painter.drawRoundedRect(rect, 15, 15);
    QWidget::paintEvent(event);
}

让目标类继承movable_widget类即可