在Qt应用程序开发中,经常会遇到需要自定义输入控件的需求。其中,对于QDoubleSpinBox控件,如果希望在点击时弹出一个自定义的软键盘,以便用户输入数值,并将输入的值设置给QDoubleSpinBox,该如何实现呢?
在本文中,我们将介绍如何使用Qt框架,结合自定义的软键盘,实现一个可以在QDoubleSpinBox控件下方弹出的数字输入解决方案。我们将从头开始构建这个功能,并逐步引导您完成实现过程。
首先,我们将创建一个名为CustomDoubleSpinBox的自定义控件,它是QDoubleSpinBox的子类。我们将重写focusInEvent函数,该函数在QDoubleSpinBox获取焦点时被调用。在这个函数中,我们将创建并显示我们自己设计的软键盘CustomKeyboard,并确保它在QDoubleSpinBox的下方弹出。
接着,我们将继续创建CustomKeyboard类,它是一个继承自QWidget的自定义控件。在CustomKeyboard中,我们将实现一个数字键盘,允许用户输入数字,并在确认后返回输入的数值。
#ifndef CUSTOMKEYBOARD_H
#define CUSTOMKEYBOARD_H
#include <QObject>
#include <QWidget>
#include <QDebug>
#include <QLabel>
#include <QGridLayout>
#include <QPushButton>
#include <QDebug>
class CustomKeyboard : public QWidget
{
Q_OBJECT
public:
explicit CustomKeyboard(QWidget *parent = nullptr);
double getValue() const;
signals:
void confirmed(double);
private:
QString currentValue;
QLabel *m_pCurrentLab;
private slots:
void on_digitButton_clicked();
void on_decimalButton_clicked();
void on_backspaceButton_clicked();
void on_clearButton_clicked();
void on_confirmButton_clicked();
void on_closeButton_clicked();
};
#endif // CUSTOMKEYBOARD_H
#include "customkeyboard.h"
CustomKeyboard::CustomKeyboard(QWidget *parent) : QWidget(parent)
{
this->setWindowFlag(Qt::FramelessWindowHint);
QVBoxLayout *layout = new QVBoxLayout;
currentValue = "";
m_pCurrentLab = new QLabel();
QGridLayout *gridLayout = new QGridLayout;
gridLayout->addWidget(m_pCurrentLab,0,0,1, 3);
m_pCurrentLab->setStyleSheet("color:black");
for (int i = 0; i <= 9; ++i)
{
QPushButton *digitButton = new QPushButton(QString::number(i));
connect(digitButton, &QPushButton::clicked, this, &CustomKeyboard::on_digitButton_clicked);
if(i == 9)
{
gridLayout->addWidget(digitButton, 4, 1);
}
else
gridLayout->addWidget(digitButton, i / 3 +1, i % 3+1);
}
QPushButton *decimalButton = new QPushButton(".");
connect(decimalButton, &QPushButton::clicked, this, &CustomKeyboard::on_decimalButton_clicked);
gridLayout->addWidget(decimalButton, 4, 2);
QPushButton *backspaceButton = new QPushButton("Backspace");
connect(backspaceButton, &QPushButton::clicked, this, &CustomKeyboard::on_backspaceButton_clicked);
gridLayout->addWidget(backspaceButton, 5, 2);
QPushButton *clearButton = new QPushButton("Clear");
connect(clearButton, &QPushButton::clicked, this, &CustomKeyboard::on_clearButton_clicked);
gridLayout->addWidget(clearButton,4, 3);
QPushButton *confirmButton = new QPushButton("Confirm");
connect(confirmButton, &QPushButton::clicked, this, &CustomKeyboard::on_confirmButton_clicked);
gridLayout->addWidget(confirmButton, 5, 1, 1, 1);
QPushButton *closeButton = new QPushButton("Close");
connect(closeButton, &QPushButton::clicked, this, &CustomKeyboard::on_closeButton_clicked);
gridLayout->addWidget(closeButton, 5, 3, 1, 1);
layout->addLayout(gridLayout);
setLayout(layout);
this->setStyleSheet("QLabel{font: 22px;color:white;}\
QPushButton{background-color:rgb(42, 49, 66);border: 1px solid rgb(206,206,206);border-radius: 5px;font:18px;Min-width:112px;Max-width:112px;Min-height:35px;color:white}\
QPushButton:hover{background-color:rgb(210,210,210);}\
QPushButton:pressed{background-color:rgb(160,160,160);}");
}
double CustomKeyboard::getValue() const
{
return currentValue.toDouble();
}
void CustomKeyboard::on_digitButton_clicked()
{
QPushButton *clickedButton = qobject_cast<QPushButton*>(sender());
currentValue += clickedButton->text();
m_pCurrentLab->setText(currentValue);
}
void CustomKeyboard::on_decimalButton_clicked()
{
if (!currentValue.contains('.'))
{
currentValue += '.';
}
m_pCurrentLab->setText(currentValue);
}
void CustomKeyboard::on_backspaceButton_clicked()
{
currentValue.chop(1);
m_pCurrentLab->setText(currentValue);
}
void CustomKeyboard::on_clearButton_clicked()
{
currentValue = "0";
m_pCurrentLab->setText(currentValue);
}
void CustomKeyboard::on_confirmButton_clicked()
{
emit confirmed(getValue());
}
void CustomKeyboard::on_closeButton_clicked()
{
this->close();
this->deleteLater();
}
在完成这两个自定义控件的设计后,我们将把它们组合在一起,实现自定义的QDoubleSpinBox软键盘功能。当用户点击QDoubleSpinBox控件时,我们的自定义软键盘将弹出,并在用户输入数字后自动设置给QDoubleSpinBox,使整个输入流程更加便捷和友好。
// customdoublespinbox.h
#ifndef CUSTOMDOUBLESPINBOX_H
#define CUSTOMDOUBLESPINBOX_H
#include <QDoubleSpinBox>
#include "customkeyboard.h"
class CustomDoubleSpinBox : public QDoubleSpinBox
{
Q_OBJECT
public:
explicit CustomDoubleSpinBox(QWidget *parent = nullptr);
protected:
void focusInEvent(QFocusEvent *event) override;
private:
CustomKeyboard *keyboard;
};
#endif // CUSTOMDOUBLESPINBOX_H
// customdoublespinbox.cpp
#include "customdoublespinbox.h"
#include <QFocusEvent>
#include <QApplication>
#include <QDesktopWidget>
CustomDoubleSpinBox::CustomDoubleSpinBox(QWidget *parent) : QDoubleSpinBox(parent)
{
// 初始化成员变量
keyboard = nullptr;
}
void CustomDoubleSpinBox::focusInEvent(QFocusEvent *event)
{
// 在QDoubleSpinBox获取焦点时弹出软键盘
if (keyboard == nullptr)
{
// 获取主屏幕的尺寸
QRect primaryScreenRect = QApplication::primaryScreen()->geometry();
// 创建一个 CustomKeyboard 实例
keyboard = new CustomKeyboard(this);
connect(keyboard, &CustomKeyboard::confirmed, [this]() {
// 从 CustomKeyboard 获取输入的值并设置给 QDoubleSpinBox
double value = this->valueFromText(QString::number(keyboard->getValue()));
this->setValue(value);
keyboard->deleteLater(); // 关闭软键盘
});
// 将 CustomKeyboard 设置为 QDoubleSpinBox 的特殊键盘
this->setSpecialValueText(" ");
this->setKeyboardTracking(false);
// 获取 QDoubleSpinBox 在主窗口中的位置
QPoint spinBoxPos = this->mapToGlobal(QPoint(0, this->height()));
// 设置 CustomKeyboard 在 QDoubleSpinBox 下方弹出
keyboard->move(spinBoxPos.x(), spinBoxPos.y());
keyboard->show();
}
QDoubleSpinBox::focusInEvent(event);
}
通过本文的介绍和示例代码,您将学会如何在Qt应用程序中实现自定义的QDoubleSpinBox软键盘功能。这将为您的应用程序带来更好的用户体验,并增加交互性。如果您对此功能感兴趣,可以参考本文提供的示例代码,并将其应用于您自己的项目中。
希望本文对您有所帮助,并且能够在Qt应用程序开发中为您带来更多灵活、个性化的控件定制体验。如果您有任何问题或建议,欢迎在评论区留言,我们将竭诚为您解答。谢谢阅读!