1. 什麽也不要說。先上效果圖：

2. 代碼

頭文件：

#ifndef APPSEARCHLINE_H
#define APPSEARCHLINE_H

#include <QLineEdit>

class AppSearchLine : public QLineEdit
{
    Q_OBJECT
public:
    AppSearchLine(QWidget *parent = 0);
};

#endif // APPSEARCHLINE_H

#include "appsearchline.h"
#include <QHBoxLayout>
#include <QPushButton>
AppSearchLine::AppSearchLine(QWidget *parent)
    :QLineEdit(parent)
{
    QHBoxLayout *mainLayout = new QHBoxLayout;
    QPushButton *searchBtn = new QPushButton;
    searchBtn->setFixedSize(13,13);
    searchBtn->setCursor(Qt::PointingHandCursor);
    searchBtn->setToolTip(tr("搜索"));
    searchBtn->setStyleSheet("QPushButton{border-image:url(:/image/resources/image/search-icon.png);"
                             "background:transparent;cursor:pointer;}");
    setPlaceholderText(tr("搜索"));
    mainLayout->addWidget(searchBtn);
    mainLayout->addStretch();
    //mainLayout->setContentsMargins(8,8,8,8);
    mainLayout->setContentsMargins(8,0,0,0);
    setTextMargins(13+8+2,0,0,0);
    setContentsMargins(0,0,0,0);
    setLayout(mainLayout);
    setStyleSheet("height:29px;border:1px solid #eaeaea;border-radius:14px;");
}
 

簡單講一下代碼，這裏用到的搜索圖標大小為13*13，所以那個搜索button設置為固定大小13*13，代碼中的

mainLayout->setContentsMargins(8,0,0,0);

另一句

setTextMargins(13+8+2,0,0,0);

好了。代碼就是那麽簡單。

qt自己定義搜索框（超簡單，帶效果圖）