Qlabel實現高亮顯示搜索關鍵字封裝類

1.1   封裝高亮顯示檢索關鍵字控件

 

 

需要對搜索的關鍵字進行高亮顯示，而QLabel只能通過setstytlesheet函數去設置一種字體顏色，無法實現一行文字多種顏色，像這種名字中把搜索關鍵字高亮顯示的需求，無法用簡單的QLabel實現，可以通過QTextDocument加載html腳本，來實現檢索關鍵詞高亮顯示，有多個關鍵詞時，都會高亮顯示；封裝成一個類，只需要設置進去顯示文字和高亮文字就可以了。實現方法如下所示：

（1）頭文件

#ifndef COLLORLABEL_H
#define COLLORLABEL_H

#include <QObject>
#include <QLabel>
#include <QTextDocument>
class CollorLabel : public QLabel
{
    Q_OBJECT

public:
    CollorLabel();
    ~CollorLabel();
    void paintEvent(QPaintEvent *event);
    void SetName(QString strName) { m_strName = strName; };
    
    void SetfilterHover(QString filterHover) { m_filterHover = filterHover; };
private:
    QString m_strName="";
    QString m_filterHover="";
    QTextDocument* m_LabelName;
};

#endif // COLLORLABEL_H

 

（2）源文件

#include "CollorLabel.h"
#include <QPainter>
#include <QColor>
#include <QBrush>
#include <QRect>
#include <QPoint>
CollorLabel::CollorLabel()
{
    m_LabelName=new QTextDocument(this);
    m_LabelName->setUndoRedoEnabled(false);
    m_LabelName->setDocumentMargin(0);
    //背景色設置爲透明，這樣鼠標放入就有hover的顏色
    setStyleSheet(QLatin1String("QLabel\n"
        "{\n"
        "    font-family: Microsoft YaHei UI;\n"
        "    font-size: 16px;\n"
        "    color: rgba(255,255,255,0.70);\n"
        "    letter-spacing: 0;\n"
        "    line-height: 24px;\n"
        "    background: rgba(255,255,255,0);\n"
        "    background:transparent;\n"
        "}\n"
        "QToolTip\n"
        "{\n"
        "    font-size:14px;\n"
        "    width:1024;\n"
        "    height:40;\n"
        "    font-family: Microsoft YaHei UI;\n"
        "}"));

    setAttribute(Qt::WA_TranslucentBackground);
}

CollorLabel::~CollorLabel()
{

}

void CollorLabel::paintEvent(QPaintEvent *event)
{
    QPainter ffpainter(this);
    QPainter* painter = &ffpainter;
    painter->save();

    //QBrush background_brush= QColor(255, 255, 255, 0);    // 透明色
    //painter->fillRect(this->rect(), background_brush);
    QColor text_color=QColor(255,255,255,0.7);          // 文本顏色
    QColor filter_color= QColor(250, 50, 57, 255);      // 高亮顏色
                                                          // 高亮文本
    QString filter_text = m_filterHover;  // 文字與過濾文字首先獲取出來
    QString text = m_strName;
    painter->setFont(this->font());

    QFontMetrics font_metrics(this->font());
    int text_width = this->width();

    m_LabelName->setDefaultFont(this->font());

    // 右部顯示省略號
    QFontMetrics font_width(this->font());
    text = font_width.elidedText(text, Qt::ElideRight, text_width);

    // 然後將匹配項加上font-color標籤，若非空的話
    if (!filter_text.isEmpty())
    {
        int last_index = text.lastIndexOf(filter_text, -1, Qt::CaseInsensitive);
        while (last_index != -1)
        {
            text.insert(last_index + filter_text.length(), "</font>");
            text.insert(last_index, QString("<font color=%1>").arg(filter_color.name()));
            last_index = text.lastIndexOf(filter_text, last_index, Qt::CaseInsensitive);
        }
    }

    // 在文檔中設置字體，並設置文字
    m_LabelName->setHtml(QString("<font color=%1>%2</font>").arg(text_color.name()).arg(text));
    int y = this->height();//居中顯示高度
    y = y / 2 - 10;
    if (y<0)
    {
        y = 0;
    }
    QRect text_rect = QRect(this->x(), y, text_width, 20);  // 文字高度爲20，所以文字上下空白爲6px
    painter->translate(QPoint(text_rect.x(), text_rect.y() + (text_rect.height() - font_metrics.height()) / 2));
    m_LabelName->drawContents(painter, text_rect.translated(-text_rect.x(), -text_rect.y()));

    painter->restore();
    

    
    
}

 

（3）對象的創建和調用

m_LabelName = new CollorLabel();

m_LabelName->setParent(ui.widgetName);

ui.horizontalLayoutName->addWidget(m_LabelName);

m_LabelName->SetName(info.value("name").toString());

m_LabelName->setToolTip(info.value("name").toString());