QT自制软键盘最完美、最简单、支持中文输入（二）-编程知识

一、前言

二、本自制虚拟键盘特点

三、中文输入原理

四、组合键输入

五、键盘事件模拟

六、界面

七、代码

7.1 frmKeyBoard 头文件代码

7.2 frmKeyBoard 源文件代码

八、使用示例

九、效果

十、结语

一、前言

由于系统自带虚拟键盘不一定好用，也不一定好看，有的按键太小，有的电脑上可能没有自带的软键盘，干脆直接自己设计一个。

在现代的用户界面设计中，屏幕键盘是一种重要的辅助工具，特别是在触摸屏设备上。本文将深入解析一个使用Qt框架自制的屏幕键盘，具有丰富的功能和用户友好的界面，支持中文输入、组合键操作等多种特性。

之前写过一篇不带中文的屏幕键盘，本文在该基础上升级部分功能：QT自制软键盘最完美、最简单、跟自带虚拟键盘一样（一）

二、本自制虚拟键盘特点

1.支持中文输入。

2.支持组合键，例如“Ctrl+C”复制粘贴操作。

3.键盘界面保持在所有界面最上方。

4.点击键盘按钮不会改变底层文本输入框焦点。

5.通过模拟键盘点击事件完成键盘输入文本信息。

6.包含各种键盘自带符号输入。

7.长按按键可以持续重复输入键盘内容。

三、中文输入原理

资源中包含了“PinYin_Chinese.txt”文本文件，文件内容为七千多个汉字以及对应的拼音，通过加载中文拼音数据，实现了基于拼音的中文输入。在用户输入拼音时，屏幕键盘匹配对应的汉字词组，并显示在候选列表中。

加载中文汉字代码：

void frmKeyBoard::loadChineseFontData()
{QFile pinyin(":/PinYin_Chinese.txt");if (!pinyin.open(QIODevice::ReadOnly)) {qDebug() << "Open pinyin file failed!";return;}while (!pinyin.atEnd()) {QString buf = QString::fromUtf8(pinyin.readLine()).trimmed();if (buf.isEmpty())continue;/* 去除#号后的注释内容 */if (buf.left(1) == "#")continue;buf=buf.replace("\t"," ");QString pinyin = buf.mid(1,buf.size() - 1);QString word = buf.mid(0,1);QString abb;QStringList pinyinList = pinyin.split(" ");for (int i = 0; i < pinyinList.count(); i++) {/* 获得拼音词组的首字母(用于缩写匹配) */abb += pinyinList.at(i).left(1);}QList<QPair<QString, QString>> &tmp = m_data[pinyin.left(1)];/* 将'拼音(缩写)'和'词组'写入匹配容器 */tmp.append(qMakePair(abb, word));/* 将'拼音(全拼)'和'词组'写入匹配容器 */tmp.append(qMakePair(pinyin.remove(" "), word));}qDebug() << m_data.size();pinyin.close();
}

点击列表选择汉字输入：

void frmKeyBoard::on_listWidget_itemClicked(QListWidgetItem *item)
{QKeyEvent keyPress(QEvent::KeyPress, 0, m_curModifier, item->text().right(1));QKeyEvent keyRelease(QEvent::KeyRelease, 0, m_curModifier, item->text().right(1));QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);ui.listWidget->clear();m_showTextList.clear();m_curPage = 0;m_labelShowPinyin->clear();recordLitterBuf.clear();
}

另外，点击汉字对应的数字、点击空格都可以输入汉字，点击回车输入对应的英文字母，部分关键代码：


void frmKeyBoard::slotKeyButtonClicked()
{QPushButton* pbtn = (QPushButton*)sender();QString objectName = pbtn->objectName();if (pbtn->text().contains("Backspace")) {if(isChinese){if(recordLitterBuf.size() > 0){recordLitterBuf.remove(recordLitterBuf.size() - 1, 1);findChineseFontData(recordLitterBuf);if(!m_labelShowPinyin->text().isEmpty())m_labelShowPinyin->setText(recordLitterBuf);}}else{QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Backspace, m_curModifier);QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Backspace, m_curModifier);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}}else if(pbtn->text() == "Space") {if(isChinese){if(ui.listWidget->count() > 0){//按下空格输入列表第一汉字on_listWidget_itemClicked(ui.listWidget->item(0));}}else{QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Space, m_curModifier, " ");QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Space, m_curModifier, " ");QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}}else if (pbtn->text().contains("Enter")) {        if(isChinese){if(!m_labelShowPinyin->text().isEmpty()){//按下回车输入拼音字母QKeyEvent keyPress(QEvent::KeyPress, 0, m_curModifier, m_labelShowPinyin->text());QKeyEvent keyRelease(QEvent::KeyRelease, 0,m_curModifier, m_labelShowPinyin->text());QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);ui.listWidget->clear();m_showTextList.clear();m_curPage = 0;m_labelShowPinyin->clear();recordLitterBuf.clear();}}else{QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Enter, m_curModifier);QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Enter, m_curModifier);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}}else if (pbtn->text().contains("Shift")) {if (pbtn->isChecked()) {isChinese = true;m_curModifier = Qt::ShiftModifier;for (auto pbtnKey : m_letterKeys) {pbtnKey->setText(pbtnKey->text().toUpper());}}else {isChinese = false;ui.listWidget->clear();m_showTextList.clear();m_curPage = 0;m_labelShowPinyin->clear();recordLitterBuf.clear();m_curModifier = Qt::NoModifier;for (auto pbtnKey : m_letterKeys) {pbtnKey->setText(pbtnKey->text().toLower());}}QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Shift, m_curModifier);QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Shift, m_curModifier);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}
//......else {QString symbol;if (ui.pushButton_shift->isChecked())symbol = pbtn->text().split("\n").at(0);elsesymbol = pbtn->text().split("\n").at(1);QKeyEvent keyPress(QEvent::KeyPress, m_mapSymbolKeys.value(symbol), m_curModifier, symbol);QKeyEvent keyRelease(QEvent::KeyRelease, m_mapSymbolKeys.value(symbol), m_curModifier, symbol);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}
}

四、组合键输入

4.1 定义m_curModifier 记录当前键盘模式。

Qt::KeyboardModifier m_curModifier = Qt::NoModifier;

4.2 特殊按键选中时切换对应的按键模式

if (pbtn->text().contains("Ctrl")) {if(pbtn->isChecked())m_curModifier = Qt::ControlModifier;elsem_curModifier = Qt::NoModifier;QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Control, m_curModifier);QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Control, m_curModifier);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}

五、键盘事件模拟

通过模拟键盘事件，实现了对底层文本输入框的模拟输入。这样，用户可以在使用屏幕键盘的同时，保持对其他界面元素的操作。

QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Enter, m_curModifier);
QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Enter, m_curModifier);
QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);
QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);

另外，通过qApp->focusWidget()获取当前焦点所在的窗口，可以将键盘模拟输入到各个窗口的输入框中。

六、界面

界面新增了一个QListWidget用于显示候选汉字列表，列表方向从左至右。

七、代码

7.1 frmKeyBoard 头文件代码

#pragma once
#pragma execution_character_set("utf-8")#include <QDialog>
#include "ui_frmKeyBoard.h"
#include <QPushButton>
#include <QKeyEvent>
#include <QDebug>
#include <QStyle>
#include <QListWidgetItem>
#include <QLabel>
#include <QVBoxLayout>
#include <QToolTip>class frmKeyBoard : public QDialog
{Q_OBJECTpublic:frmKeyBoard(QWidget *parent = nullptr);~frmKeyBoard();void initFocusWidget(QWidget*);private slots:void slotKeyButtonClicked();void slotKeyLetterButtonClicked();void slotKeyNumberButtonClicked();void on_listWidget_itemClicked(QListWidgetItem *item);void on_toolButton_lastPage_clicked();void on_toolButton_nextPage_clicked();private:Ui::frmKeyBoardClass ui;void initFrm();void initStyleSheet();void loadChineseFontData();void findChineseFontData(QString text);void addOneItem(QString text);QMap<QString, QList<QPair<QString, QString>>> m_data;bool isChinese = false;QString recordLitterBuf;QVector<QPushButton*> m_letterKeys;QVector<QPushButton*> m_NumberKeys;QMap<QString, Qt::Key> m_mapSymbolKeys;QStringList m_showTextList;int m_curPage = 0;QLabel* m_labelShowPinyin;Qt::KeyboardModifier m_curModifier = Qt::NoModifier;
};

7.2 frmKeyBoard 源文件代码

#include "frmKeyBoard.h"frmKeyBoard::frmKeyBoard(QWidget *parent): QDialog(parent)
{ui.setupUi(this);this->setWindowFlags(Qt::WindowStaysOnTopHint | Qt::WindowDoesNotAcceptFocus);this->setWindowTitle("屏幕键盘（源客V）");this->setWindowModality(Qt::WindowModal);this->setAttribute(Qt::WA_DeleteOnClose);this->initFrm();this->initStyleSheet();this->loadChineseFontData();
}frmKeyBoard::~frmKeyBoard()
{
}void frmKeyBoard::initFrm()
{m_letterKeys.clear();m_NumberKeys.clear();QList<QPushButton*> pbtns = this->findChildren<QPushButton*>();foreach(QPushButton * pbtn, pbtns) {pbtn->setAutoRepeat(true);    //允许自动重复pbtn->setAutoRepeatDelay(500);//设置重复操作的时延if (pbtn->text() >= 'a' && pbtn->text() <= 'z') {connect(pbtn, &QPushButton::clicked, this, &frmKeyBoard::slotKeyLetterButtonClicked);m_letterKeys.push_back(pbtn);}else if (pbtn->text().toInt() > 0 && pbtn->text().toInt() <= 9 || pbtn->text() == "0") {connect(pbtn, &QPushButton::clicked, this, &frmKeyBoard::slotKeyNumberButtonClicked);m_NumberKeys.push_back(pbtn);}else{connect(pbtn, &QPushButton::clicked, this, &frmKeyBoard::slotKeyButtonClicked);}}//添加label显示拼音m_labelShowPinyin = new QLabel();QVBoxLayout* vLayout = new QVBoxLayout();vLayout->addWidget(m_labelShowPinyin);vLayout->addStretch();ui.listWidget->setLayout(vLayout);m_mapSymbolKeys.insert("~", Qt::Key_AsciiTilde);m_mapSymbolKeys.insert("`", Qt::Key_nobreakspace);m_mapSymbolKeys.insert("-", Qt::Key_Minus);m_mapSymbolKeys.insert("_", Qt::Key_Underscore);m_mapSymbolKeys.insert("+", Qt::Key_Plus);m_mapSymbolKeys.insert("=", Qt::Key_Equal);m_mapSymbolKeys.insert(",", Qt::Key_Comma);m_mapSymbolKeys.insert(".", Qt::Key_Period);m_mapSymbolKeys.insert("/", Qt::Key_Slash);m_mapSymbolKeys.insert("<", Qt::Key_Less);m_mapSymbolKeys.insert(">", Qt::Key_Greater);m_mapSymbolKeys.insert("?", Qt::Key_Question);m_mapSymbolKeys.insert("[", Qt::Key_BracketLeft);m_mapSymbolKeys.insert("]", Qt::Key_BracketRight);m_mapSymbolKeys.insert("{", Qt::Key_BraceLeft);m_mapSymbolKeys.insert("}", Qt::Key_BraceRight);m_mapSymbolKeys.insert("|", Qt::Key_Bar);m_mapSymbolKeys.insert("\\", Qt::Key_Backslash);m_mapSymbolKeys.insert(":", Qt::Key_Colon);m_mapSymbolKeys.insert(";", Qt::Key_Semicolon);m_mapSymbolKeys.insert("\"", Qt::Key_QuoteLeft);m_mapSymbolKeys.insert("'", Qt::Key_Apostrophe);
}void frmKeyBoard::initStyleSheet()
{QString qss;qss += "QWidget{ background-color:rgb(26,26,26)}";    qss += "QToolButton{ color:white; font:bold 11pt;}";qss += "QLabel{ color:white; font:13pt;}";qss += "QListWidget{ color:white; border:none; padding-bottom:10px; }";qss += "QListWidget::item:hover,QListWidget::item:selected{font:bold; color:yellow; background-color:rgba(0,0,0,0)}";qss += "QPushButton{ color:white; background-color:rgb(51,51,51); height:50px; font-size:bold 15pt; border:1px solid rgb(26,26,26); border-radius: 0px; min-width:50px;}";qss += "QPushButton:hover{background-color:rgb(229,229,229); color:black;}";qss += "QPushButton:pressed,QPushButton:checked{background-color:rgb(0,118,215);}";qss += "#pushButton_closeKeyboard{background-color:rgba(0,0,0,0); border:0px}";qss += "#pushButton_closeKeyboard:hover{background-color:#b30220;}";qss += "#pushButton_space{min-width:500px;}";qss += "#pushButton_backspace,#pushButton_shift{min-width:100px;}";qss += "#pushButton_enter{min-width:120px;}";qss += "#pushButton_tab,#pushButton_ctrl{min-width:70px;}";qss += "#pushButton_capsLock{min-width:80px;}";qss += "#pushButton_up{min-width:150px;}";this->setStyleSheet(qss);
}void frmKeyBoard::loadChineseFontData()
{QFile pinyin(":/PinYin_Chinese.txt");if (!pinyin.open(QIODevice::ReadOnly)) {qDebug() << "Open pinyin file failed!";return;}while (!pinyin.atEnd()) {QString buf = QString::fromUtf8(pinyin.readLine()).trimmed();if (buf.isEmpty())continue;/* 去除#号后的注释内容 */if (buf.left(1) == "#")continue;buf=buf.replace("\t"," ");QString pinyin = buf.mid(1,buf.size() - 1);QString word = buf.mid(0,1);QString abb;QStringList pinyinList = pinyin.split(" ");for (int i = 0; i < pinyinList.count(); i++) {/* 获得拼音词组的首字母(用于缩写匹配) */abb += pinyinList.at(i).left(1);}QList<QPair<QString, QString>> &tmp = m_data[pinyin.left(1)];/* 将'拼音(缩写)'和'词组'写入匹配容器 */tmp.append(qMakePair(abb, word));/* 将'拼音(全拼)'和'词组'写入匹配容器 */tmp.append(qMakePair(pinyin.remove(" "), word));}qDebug() << m_data.size();pinyin.close();
}void frmKeyBoard::findChineseFontData(QString text)
{QString lowerText = text.toLower();m_labelShowPinyin->setText(lowerText);for (int i = 0; i < ui.listWidget->count(); i++) {QListWidgetItem *item = ui.listWidget->takeItem(i);delete item;item = NULL;}ui.listWidget->clear();m_showTextList.clear();m_curPage = 0;if(lowerText.count() <= 0)return;const QList<QPair<QString, QString> > &tmp = m_data[lowerText.left(1)];bool fond = false;for (int i = 0; i < tmp.count(); i++) {const QPair<QString, QString> &each = tmp.at(i);if (each.first.left(lowerText.count()) != lowerText)continue;fond = true;addOneItem(each.second);m_showTextList.push_back(each.second);}if(!fond){if(recordLitterBuf.count() > 1){recordLitterBuf = recordLitterBuf.right(1);findChineseFontData(recordLitterBuf);}else{QKeyEvent keyPress(QEvent::KeyPress, int(recordLitterBuf.at(0).toLatin1()), m_curModifier, recordLitterBuf);QKeyEvent keyRelease(QEvent::KeyRelease, int(recordLitterBuf.at(0).toLatin1()), m_curModifier, recordLitterBuf);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}}
}void frmKeyBoard::addOneItem(QString text)
{if(ui.listWidget->count() >= 9)return;QString itemText = QString("%1.%2").arg(ui.listWidget->count() + 1).arg(text);QListWidgetItem *item = new QListWidgetItem(itemText);QFont font;font.setPointSize(15);font.setBold(true);font.setWeight(50);item->setFont(font);/* 设置文字居中 */item->setTextAlignment(Qt::AlignBottom | Qt::AlignHCenter);bool isChineseFlag = QRegExp("^[\u4E00-\u9FA5]+").indexIn(text.left(1)) != -1;int width = font.pointSize();if (isChineseFlag)width += itemText.count()*font.pointSize()*1.5;elsewidth += itemText.count()*font.pointSize()*2/3;item->setSizeHint(QSize(width, 50));ui.listWidget->addItem(item);
}void frmKeyBoard::slotKeyButtonClicked()
{QPushButton* pbtn = (QPushButton*)sender();QString objectName = pbtn->objectName();if (pbtn->text().contains("Backspace")) {if(isChinese){if(recordLitterBuf.size() > 0){recordLitterBuf.remove(recordLitterBuf.size() - 1, 1);findChineseFontData(recordLitterBuf);if(!m_labelShowPinyin->text().isEmpty())m_labelShowPinyin->setText(recordLitterBuf);}}else{QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Backspace, m_curModifier);QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Backspace, m_curModifier);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}}else if (pbtn->text().contains("Caps")) {if (pbtn->isChecked()) {for (auto pbtnKey : m_letterKeys) {pbtnKey->setText(pbtnKey->text().toUpper());}}else {for (auto pbtnKey : m_letterKeys) {pbtnKey->setText(pbtnKey->text().toLower());}}}else if(pbtn->text() == "Space") {if(isChinese){if(ui.listWidget->count() > 0){on_listWidget_itemClicked(ui.listWidget->item(0));}}else{QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Space, m_curModifier, " ");QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Space, m_curModifier, " ");QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}}else if (pbtn->text().contains("Tab")) {QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Tab, m_curModifier);QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Tab, m_curModifier);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}else if (pbtn->text().contains("Enter")) {        if(isChinese){if(!m_labelShowPinyin->text().isEmpty()){QKeyEvent keyPress(QEvent::KeyPress, 0, m_curModifier, m_labelShowPinyin->text());QKeyEvent keyRelease(QEvent::KeyRelease, 0,m_curModifier, m_labelShowPinyin->text());QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);ui.listWidget->clear();m_showTextList.clear();m_curPage = 0;m_labelShowPinyin->clear();recordLitterBuf.clear();}}else{QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Enter, m_curModifier);QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Enter, m_curModifier);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}}else if (pbtn->text().contains("Shift")) {if (pbtn->isChecked()) {isChinese = true;m_curModifier = Qt::ShiftModifier;for (auto pbtnKey : m_letterKeys) {pbtnKey->setText(pbtnKey->text().toUpper());}}else {isChinese = false;ui.listWidget->clear();m_showTextList.clear();m_curPage = 0;m_labelShowPinyin->clear();recordLitterBuf.clear();m_curModifier = Qt::NoModifier;for (auto pbtnKey : m_letterKeys) {pbtnKey->setText(pbtnKey->text().toLower());}}QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Shift, m_curModifier);QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Shift, m_curModifier);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}else if (pbtn->text().contains("Ctrl")) {if(pbtn->isChecked())m_curModifier = Qt::ControlModifier;elsem_curModifier = Qt::NoModifier;QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Control, m_curModifier);QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Control, m_curModifier);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}else if (pbtn->text().contains("Win")) {QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Menu, m_curModifier);QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Menu, m_curModifier);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}else if (pbtn->text().contains("Alt")) {if(pbtn->isChecked())m_curModifier = Qt::AltModifier;elsem_curModifier = Qt::NoModifier;QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Alt, m_curModifier);QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Alt, m_curModifier);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}else if (pbtn->text().contains("↑")) {QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Up, m_curModifier);QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Up, m_curModifier);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}else if (pbtn->text().contains("↓")) {QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Down, m_curModifier);QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Down, m_curModifier);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}else if (pbtn->text().contains("←")) {QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Left, m_curModifier);QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Left, m_curModifier);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}else if (pbtn->text().contains("→")) {QKeyEvent keyPress(QEvent::KeyPress, Qt::Key_Right, m_curModifier);QKeyEvent keyRelease(QEvent::KeyRelease, Qt::Key_Right, m_curModifier);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}else {QString symbol;if (ui.pushButton_shift->isChecked())symbol = pbtn->text().split("\n").at(0);elsesymbol = pbtn->text().split("\n").at(1);QKeyEvent keyPress(QEvent::KeyPress, m_mapSymbolKeys.value(symbol), m_curModifier, symbol);QKeyEvent keyRelease(QEvent::KeyRelease, m_mapSymbolKeys.value(symbol), m_curModifier, symbol);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}
}void frmKeyBoard::slotKeyLetterButtonClicked()
{QPushButton* pbtn = (QPushButton*)sender();if (pbtn->text() >= 'a' && pbtn->text() <= 'z') {if(isChinese){recordLitterBuf+=pbtn->text().toLower();findChineseFontData(recordLitterBuf);}else{ui.listWidget->clear();m_showTextList.clear();m_curPage = 0;m_labelShowPinyin->clear();recordLitterBuf.clear();QKeyEvent keyPress(QEvent::KeyPress, int(pbtn->text().at(0).toLatin1()) - 32, m_curModifier, pbtn->text());QKeyEvent keyRelease(QEvent::KeyRelease, int(pbtn->text().at(0).toLatin1()) - 32, m_curModifier, pbtn->text());QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}}else if (pbtn->text() >= 'A' && pbtn->text() <= 'Z') {if(isChinese){recordLitterBuf+=pbtn->text().toLower();findChineseFontData(recordLitterBuf);}else{ui.listWidget->clear();m_showTextList.clear();m_curPage = 0;m_labelShowPinyin->clear();recordLitterBuf.clear();QKeyEvent keyPress(QEvent::KeyPress, int(pbtn->text().at(0).toLatin1()), m_curModifier, pbtn->text());QKeyEvent keyRelease(QEvent::KeyRelease, int(pbtn->text().at(0).toLatin1()), m_curModifier, pbtn->text());QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);}}if (ui.pushButton_ctrl->isChecked())ui.pushButton_ctrl->setChecked(false);if (ui.pushButton_win->isChecked())ui.pushButton_win->setChecked(false);if (ui.pushButton_alt->isChecked())ui.pushButton_alt->setChecked(false);m_curModifier = Qt::NoModifier;
}void frmKeyBoard::slotKeyNumberButtonClicked()
{QPushButton* pbtn = (QPushButton*)sender();int num = pbtn->text().toInt();if(isChinese){if(num > 0 && num < 9 && ui.listWidget->count() >= num){on_listWidget_itemClicked(ui.listWidget->item(num - 1));}}else {QKeyEvent keyPress(QEvent::KeyPress, num + 48, m_curModifier, pbtn->text());QKeyEvent keyRelease(QEvent::KeyRelease, num + 48, m_curModifier, pbtn->text());QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);if (ui.pushButton_ctrl->isChecked())ui.pushButton_ctrl->setChecked(false);if (ui.pushButton_win->isChecked())ui.pushButton_win->setChecked(false);if (ui.pushButton_alt->isChecked())ui.pushButton_alt->setChecked(false);}m_curModifier = Qt::NoModifier;
}void frmKeyBoard::on_listWidget_itemClicked(QListWidgetItem *item)
{QKeyEvent keyPress(QEvent::KeyPress, 0, m_curModifier, item->text().right(1));QKeyEvent keyRelease(QEvent::KeyRelease, 0, m_curModifier, item->text().right(1));QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyPress);QApplication::sendEvent(qApp->focusWidget() == nullptr ? this : qApp->focusWidget(), &keyRelease);ui.listWidget->clear();m_showTextList.clear();m_curPage = 0;m_labelShowPinyin->clear();recordLitterBuf.clear();
}void frmKeyBoard::on_toolButton_lastPage_clicked()
{if(m_curPage <= 0)return;m_curPage--;ui.listWidget->clear();for (int i = m_curPage * 9; i < m_curPage * 9 + 9; i++) {if(i >= m_showTextList.count())break;addOneItem(m_showTextList.at(i));}
}void frmKeyBoard::on_toolButton_nextPage_clicked()
{if(m_curPage >= m_showTextList.count() / 9)return;m_curPage++;ui.listWidget->clear();for (int i = m_curPage * 9; i < m_curPage * 9 + 9; i++) {if(i >= m_showTextList.count())break;addOneItem(m_showTextList.at(i));}
}

八、使用示例

MainWindow::MainWindow(QWidget *parent): QMainWindow(parent), ui(new Ui::MainWindow)
{ui->setupUi(this);this->setWindowTitle("屏幕键盘测试（源客V）");QHBoxLayout* layout = new QHBoxLayout();layout->setContentsMargins(0, 0, 0, 0);layout->addWidget(ui->pushButton, 0, Qt::AlignRight);ui->lineEdit->setLayout(layout);
}MainWindow::~MainWindow()
{delete ui;
}void MainWindow::on_pushButton_clicked()
{frmKeyBoard* keyBoard = new frmKeyBoard();keyBoard->show();
}