QCompleter的进阶使用

1. 获取QCompleter的生成的匹配结果

#include <QtWidgets/QCompleter>
#include <QtCore/QStringListModel>
#include <QtCore/QAbstractProxyModel>

QStringList searchList({
    "海","海龟","海底捞","海胆","火","大火","风火轮","海风"});
QCompleter c;
//模型填入父亲 c 后，completer searchList，后面替换不用主动析构
c.setModel(new QStringListModel(searchList,&c));
c.setCompletionMode(QCompleter::PopupCompletion);
c.setCaseSensitivity(Qt::CaseInsensitive);
c.setCompletionPrefix("海"); //搜索前缀
QAbstractProxyModel *completionModel = dynamic_cast<QAbstractProxyModel*>(c.completionModel());
int nCompletionCount =  completionModel->rowCount();

QStringList searchRet;
for(int i=0 ; i<nCompletionCount ; ++i){
    
    QModelIndex proxyIndex = completionModel->index(i,0);
    QModelIndex completeIndex =  completionModel->mapToSource(proxyIndex);
    searchRet.push_back(completeIndex.data().toString());
}

2. 在内置的QLineEdit中使用QCompleter

2.1如何监听QCompleter按下的案件，如回车按键等

需要对lineedit的popup 安装事件过滤器

class CLineEdit : public QLineEdit{
    
    Q_OBJECT
public:
    CLineEdit(QWidget* parent = nullptr): QLineEdit(parent){
    }
    ~CLineEdit(){
    }
private:
    bool eventFilter(QObject *obj, QEvent *event) override{
    
        if(event->type() == QEvent::KeyPress || event->type() == QEvent::KeyRelease){
    
            QKeyEvent *keyEvent = dynamic_cast<QKeyEvent*>(event);
            if(keyEvent && ( keyEvent->key() == Qt::Key_Enter ||keyEvent->key() == Qt::Key_Return)){
    
                return true;
            }
        }

        return QObject::eventFilter(obj, event);
    }
};

CLineEdit lineEdit;
lineEdit.setCompleter(new QCompleter);
lineEdit.completer()->popup()->installEventFilter(&lineEdit);