Qt 创建对话框

#ifndef FINDDIALOG_H#define FINDDIALOG_H#include <QDialog>class QCheckBox;class QLabel;class QLineEdit;class QPushButton;class FindDialog : public QDialog{    Q_OBJECT //对于所有定义了信号和槽的类，在定义开始处的Q_OBJECT都是必需的public:    FindDialog(QWidget *parent = 0);signals:    void findNext(const QString &str, Qt::CaseSensitivity cs);    void findPrevious(const QString &str, Qt::CaseSensitivity cs);private slots:    void findClicked();    void enableFindButton(const QString &text);private:    QLabel *label;    QLineEdit *lineEdit;    QCheckBox *caseCheckBox;    QCheckBox *backwardCheckBox;    QPushButton *findButton;    QPushButton *closeButton;};#endif

#include <QLabel>#include <QCheckBox>#include <QPushButton>#include <QHBoxLayout>#include <QVBoxLayout>#include <QLineEdit>#include "finddialog.h"FindDialog::FindDialog(QWidget *parent)    : QDialog(parent){    label = new QLabel(tr("Find &what:"));//快捷键Alt+W    lineEdit = new QLineEdit;    label->setBuddy(lineEdit); //设置接收快捷键焦点的伙伴    caseCheckBox = new QCheckBox(tr("Match &case"));    backwardCheckBox = new QCheckBox(tr("Search &backward"));    findButton = new QPushButton(tr("&Find"));     findButton->setDefault(true); //默认按钮    findButton->setEnabled(false);//禁用按钮    closeButton = new QPushButton(tr("Close"));    connect(lineEdit, SIGNAL(textChanged(const QString &)),            this, SLOT(enableFindButton(const QString &)));    connect(findButton, SIGNAL(clicked()),            this, SLOT(findClicked()));    connect(closeButton, SIGNAL(clicked()),            this, SLOT(close()));    QHBoxLayout *topLeftLayout = new QHBoxLayout;    topLeftLayout->addWidget(label);    topLeftLayout->addWidget(lineEdit);    QVBoxLayout *leftLayout = new QVBoxLayout;    leftLayout->addLayout(topLeftLayout);    leftLayout->addWidget(caseCheckBox);    leftLayout->addWidget(backwardCheckBox);    QVBoxLayout *rightLayout = new QVBoxLayout;    rightLayout->addWidget(findButton);    rightLayout->addWidget(closeButton);    rightLayout->addStretch();//添加弹簧（伸展器）    QHBoxLayout *mainLayout = new QHBoxLayout;    mainLayout->addLayout(leftLayout);    mainLayout->addLayout(rightLayout);    setLayout(mainLayout);    setWindowTitle(tr("Find"));    setFixedHeight(sizeHint().height());}void FindDialog::findClicked(){    QString text = lineEdit->text();    Qt::CaseSensitivity cs =            caseCheckBox->isChecked() ? Qt::CaseSensitive                                      : Qt::CaseInsensitive;    if (backwardCheckBox->isChecked()) {        emit findPrevious(text, cs);    } else {        emit findNext(text, cs);    }}void FindDialog::enableFindButton(const QString &text){    findButton->setEnabled(!text.isEmpty());}

#include <QApplication>#include "finddialog.h"int main(int argc, char *argv[]){    QApplication app(argc, argv);    FindDialog *dialog = new FindDialog;    dialog->show();    return app.exec();}

程序运行截图：