第八章 Qt GUI之对话框使用

 1 #ifndef FINDDIALOG_H
 2 #define FINDDIALOG_H
 3 
 4 #include <QDialog>
 5 #include <QCheckBox>
 6 #include <QLabel>
 7 #include <QLineEdit>
 8 #include <QPushButton>
 9 
10 class FindDialog : public QDialog
11 {
12     Q_OBJECT
13     
14 public:
15     FindDialog(QWidget *parent = 0);
16     ~FindDialog();
17 
18 signals:
19     void findNext(const QString &str, Qt::CaseSensitivity cs);
20     void findPrevious(const QString &str, Qt::CaseSensitivity cs);
21 
22 private slots:
23     void findClicked();
24     void enableFindButton(const QString &text);
25 
26 private:
27     QLabel *label;
28     QLineEdit *lineEdit;
29     QCheckBox *caseCheckBox;
30     QCheckBox *backwardCheckBox;
31     QPushButton *findButton;
32     QPushButton *closeButton;
33 };
34 
35 #endif // FINDDIALOG_H

 1 #include <QtGui>
 2 #include "finddialog.h"
 3 
 4 FindDialog::FindDialog(QWidget *parent)
 5     : QDialog(parent)
 6 {
 7     label = new QLabel(tr("Find &what")); //tr()函数是把它们翻译成其他语言的标志，“&”来表示快捷键（Alt+W）
 8     lineEdit = new QLineEdit;
 9     label->setBuddy(lineEdit);//设置行编辑器为标签的伙伴，按下标签的快捷键（Alt+W）时接收焦点，焦点会移动到行编辑器
10 
11     caseCheckBox = new QCheckBox(tr("Math &case"));
12     backwardCheckBox = new QCheckBox(tr("Search &backward"));
13 
14     findButton = new QPushButton(tr("&Find"));
15     findButton->setDefault(true);//设置“Find”按钮为默认按钮，默认按钮就是当用户Enter键时能够按下对应的按钮
16     findButton->setEnabled(false);//禁用“Find”按钮，它通常显示为灰色，不能和用户进行交互操作
17 
18     closeButton = new QPushButton(tr("Close"));
19 
20     connect(lineEdit, SIGNAL(textChanged(const QString &)), this, SLOT(enableFindButton(const QString &)));
21     connect(findButton, SIGNAL(clicked()), this, SLOT(findClicked()));
22     connect(closeButton, SIGNAL(clicked()), this, SLOT(close()));
23 
24     QHBoxLayout *topLeftLayout = new QHBoxLayout;
25     topLeftLayout->addWidget(label);
26     topLeftLayout->addWidget(lineEdit);
27 
28     QVBoxLayout *leftLayout = new QVBoxLayout;
29     leftLayout->addLayout(topLeftLayout);
30     leftLayout->addWidget(caseCheckBox);
31     leftLayout->addWidget(backwardCheckBox);
32 
33     QVBoxLayout *rightLayout = new QVBoxLayout;
34     rightLayout->addWidget(findButton);
35     rightLayout->addWidget(closeButton);
36     rightLayout->addStretch();
37 
38     QHBoxLayout *mainLayout = new QHBoxLayout;
39     mainLayout->addLayout(leftLayout);
40     mainLayout->addLayout(rightLayout);
41     setLayout(mainLayout); //将mainLayout布局安装在FindDialog
42 
43     setWindowTitle(tr("Find"));
44     setFixedHeight(sizeHint().height());
45 }
46 
47 void FindDialog::findClicked()
48 {
49     QString text = lineEdit->text();
50     Qt::CaseSensitivity cs = caseCheckBox->isChecked() ? Qt::CaseSensitive : Qt::CaseInsensitive;
51     if (backwardCheckBox->isChecked())
52     {
53         emit findPrevious(text, cs);
54     }
55     else
56     {
57         emit findNext(text, cs);
58     }
59 }
60 
61 void FindDialog::enableFindButton(const QString &text)
62 {
63     findButton->setEnabled(!text.isEmpty());
64 }
65 
66 FindDialog::~FindDialog()
67 {
68     
69 }

#include <QApplication>
#include "finddialog.h"

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    FindDialog *w = new FindDialog;
    w->show();
    
    return a.exec();
}