qt - 如何强制 QCompleter 检查 QLineEdit 中的第二个单词

Question

我有一个功能可以实现带有自动完成功能的文本框。
我找到了一个使用 QLineEdit 和 QCompleter 的代码。

因此我有我的字符串值， "one"， "two"， "three"等。

一旦我输入“on”，完成者就会向我建议列表中带有前缀“on”的每个单词。
但是在我从列表中选择“一个”并尝试输入第二个单词后，完成器不起作用。

QCompleter 或 Qt 中是否有提供此类功能的功能。我在文档中找到了它。

查看我找到的代码:

#include <QApplication>
#include<QStringList>
#include<QLineEdit>
#include<QCompleter>
#include<QHBoxLayout>
#include<QWidget>
#include<QLabel>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QWidget *win=new QWidget();
    QHBoxLayout *lay=new QHBoxLayout();
    QStringList wordList;
    wordList << "alpha" << "omega" << "omicron" << "zeta"<<"america"<<"orion"<<"amit"<<"Odssey";
    QLabel *lbl=new QLabel("Select");
    QLineEdit *lineEdit = new QLineEdit();
    lbl->setBuddy(lineEdit);
    QCompleter *completer = new QCompleter(wordList);
    completer->setCaseSensitivity(Qt::CaseInsensitive); //Make caseInsensitive selectio
    lineEdit->setCompleter(completer);
    lay->addWidget(lbl);
    lay->addWidget(lineEdit);
    win->setLayout(lay);
    win->showMaximized();
    return a.exec();
}

Answer 1

我认为您需要覆盖 QLineEdit 中的几个方法。我的代码版本:

mclineedit.h

#ifndef MCLINEEDIT_H
#define MCLINEEDIT_H

#include <QLineEdit>

class MCLineEdit : public QLineEdit
{
    Q_OBJECT
public:
    explicit MCLineEdit(QWidget *parent = 0);
    void setMultipleCompleter(QCompleter*);

protected:
    void keyPressEvent(QKeyEvent *e);

private:
    QString cursorWord(const QString& sentence) const;

private slots:
    void insertCompletion(QString);

private:
    QCompleter* c;
};

#endif // MCLINEEDIT_H

mclineedit.cpp

#include "mclineedit.h"
#include <QCompleter>
#include <QTextCursor>
#include <QAbstractItemView>
#include <QScrollBar>

MCLineEdit::MCLineEdit(QWidget *parent) :
    QLineEdit(parent)
{
}
void MCLineEdit::keyPressEvent(QKeyEvent *e)
{
    QLineEdit::keyPressEvent(e);
    if (!c)
        return;

    c->setCompletionPrefix(cursorWord(this->text()));
    if (c->completionPrefix().length() < 1)
    {
        c->popup()->hide();
        return;
    }
    QRect cr = cursorRect();
         cr.setWidth(c->popup()->sizeHintForColumn(0)
                     + c->popup()->verticalScrollBar()->sizeHint().width());
    c->complete(cr);

}
QString MCLineEdit::cursorWord(const QString &sentence) const
{
    return sentence.mid(sentence.left(cursorPosition()).lastIndexOf(" ") + 1,
                        cursorPosition() -
                        sentence.left(cursorPosition()).lastIndexOf(" ") - 1);
}

void MCLineEdit::insertCompletion(QString arg)
{
    setText(text().replace(text().left(cursorPosition()).lastIndexOf(" ") + 1,
                           cursorPosition() -
                           text().left(cursorPosition()).lastIndexOf(" ") - 1,
                           arg));
}

void MCLineEdit::setMultipleCompleter(QCompleter* completer)
{
    c = completer;
    c->setWidget(this);
    connect(c, SIGNAL(activated(QString)),
            this, SLOT(insertCompletion(QString)));
}

要了解更多信息，请访问 http://qt-project.org/doc/qt-4.8/tools-customcompleter.html (使用 QTextEdit)。