实现简易计算器 网格布局 QT环境 纯代码C++实现

#include "widget.h" #include "ui_widget.h" #define DEFULT_BUTTON_STYLE "\ QPushButton{\ color:#000000;\ border:1px solid #AAAAAA;\ border-radius:0;\ background-color:#FFFFFF;\ }\ QPushButton:pressed{\ color:#FFFFFF;\ background-color:#AAAAAA;\ }\ " Widget::Widget(QWidget *parent) : QWidget(parent), ui(new Ui::Widget) { ui->setupUi(this); this->setWindowTitle("计算器"); current_input1.clear(); // 清空字符串 current_input2.clear(); flag = 0; // flag置0 QLabel *label = new QLabel; // 结果输出框label label->setAlignment(Qt::AlignRight|Qt::AlignHCenter|Qt::AlignVCenter); // 靠右居中对齐 label->setText("0"); label->setSizePolicy(QSizePolicy::Preferred,QSizePolicy::Preferred); QPushButton *button[10]; for(int i = 0;i < 10;i++){ button[i] = new QPushButton; button[i]->setText(QString::number(i)); button[i]->setSizePolicy(QSizePolicy::Preferred,QSizePolicy::Preferred); button[i]->setStyleSheet("DEFULT_BUTTON_STYLE"); connect(button[i],&QPushButton::clicked,this,[=](){ if(flag ==0){ current_input1 += QString::number(i); // 数字转换成字符串拼接 label->setText(current_input1); // 显示到label上 } else{ current_input2 += QString::number(i); // 数字转换成字符串拼接 QString temp = current_input1 + m_operator + current_input2; // 字符串拼接 label->setText(temp); // 显示 } }); } QPushButton *add_button = new QPushButton; add_button->setText("+"); add_button->setSizePolicy(QSizePolicy::Preferred,QSizePolicy::Preferred); connect(add_button,&QPushButton::clicked,this,[=](){ m_operator = "+"; flag = 1; QString temp = current_input1 + m_operator; // 字符串拼接 label->setText(temp); // 显示 }); QPushButton *sub_button = new QPushButton; sub_button->setText("-"); sub_button->setSizePolicy(QSizePolicy::Preferred,QSizePolicy::Preferred); connect(sub_button,&QPushButton::clicked,this,[=](){ m_operator = "-"; flag = 1; QString temp = current_input1 + m_operator; label->setText(temp); // 显示 }); QPushButton *equal_button = new QPushButton; equal_button->setText("="); equal_button->setSizePolicy(QSizePolicy::Preferred,QSizePolicy::Preferred); connect(equal_button,&QPushButton::clicked,this,[=](){ num1 = current_input1.toInt(); num2 = current_input2.toInt(); if(m_operator == "+") result = num1 + num2; else if(m_operator == "-") result = num1 - num2; QString temp = QString("%1 %2 %3 = %4").arg(num1).arg(m_operator).arg(num2).arg(result); label->setText(temp); // 显示 current_input1.clear(); current_input2.clear(); num1 = 0; num2 = 0; flag = 0; }); QPushButton *clear_button = new QPushButton; clear_button->setText("C"); clear_button->setSizePolicy(QSizePolicy::Preferred,QSizePolicy::Preferred); connect(clear_button,&QPushButton::clicked,this,[=](){ current_input1.clear(); // 清空 current_input2.clear(); num1 = 0; num2 = 0; flag = 0; label->setText("0"); // 显示到label上 }); QPushButton *del_button = new QPushButton; del_button->setText("DEL"); del_button->setSizePolicy(QSizePolicy::Preferred,QSizePolicy::Preferred); connect(del_button,&QPushButton::clicked,this,[=](){ if(flag == 0){ current_input1.chop(1); // 去除尾端数字 label->setText(current_input1); } else if(flag == 1 && current_input2.isEmpty()){ m_operator =""; // 设置为空 flag = 0; label->setText(current_input1); // 显示 } else{ current_input2.chop(1); // 去除尾端数字 QString temp = current_input1 + m_operator + current_input2; label->setText(temp); // 显示 } }); QGridLayout *layout = new QGridLayout(this); // 网格布局 layout->addWidget(label,0,0,1,4); layout->addWidget(clear_button,1,0,1,1); layout->addWidget(del_button,1,1,1,1); layout->addWidget(add_button,1,2,1,1); layout->addWidget(sub_button,1,3,1,1); layout->addWidget(button[7],2,0,1,1); layout->addWidget(button[8],2,1,1,1); layout->addWidget(button[9],2,2,1,1); layout->addWidget(button[0],2,3,1,1); layout->addWidget(button[4],3,0,1,1); layout->addWidget(button[5],3,1,1,1); layout->addWidget(button[6],3,2,1,1); layout->addWidget(button[1],4,0,1,1); layout->addWidget(button[2],4,1,1,1); layout->addWidget(button[3],4,2,1,1); layout->addWidget(equal_button,3,3,2,1); layout->setMargin(0); // 边界 layout->setSpacing(0); // 各部件之间间距 } Widget::~Widget() { delete ui; }