QLineEdit控制输入格式

通过setInputMask和validator控制

 #ifndef WINDOW_H
 #define WINDOW_H

 #include <QWidget>

 class QComboBox;
 class QLineEdit;

 class Window : public QWidget
 {
     Q_OBJECT

 public:
     Window();

 public slots:
     void echoChanged(int);
     void validatorChanged(int);
     void alignmentChanged(int);
     void inputMaskChanged(int);
     void accessChanged(int);

 private:
     QLineEdit *echoLineEdit;
     QLineEdit *validatorLineEdit;
     QLineEdit *alignmentLineEdit;
     QLineEdit *inputMaskLineEdit;
     QLineEdit *accessLineEdit;
 };

 #endif

 #include <QtWidgets>

 #include "window.h"

 Window::Window()
 {
     QGroupBox *echoGroup = new QGroupBox(tr("Echo"));

     QLabel *echoLabel = new QLabel(tr("Mode:"));
     QComboBox *echoComboBox = new QComboBox;
     echoComboBox->addItem(tr("Normal"));
     echoComboBox->addItem(tr("Password"));
     echoComboBox->addItem(tr("PasswordEchoOnEdit"));
     echoComboBox->addItem(tr("No Echo"));

     echoLineEdit = new QLineEdit;
     echoLineEdit->setFocus();

     QGroupBox *validatorGroup = new QGroupBox(tr("Validator"));

     QLabel *validatorLabel = new QLabel(tr("Type:"));
     QComboBox *validatorComboBox = new QComboBox;
     validatorComboBox->addItem(tr("No validator"));
     validatorComboBox->addItem(tr("Integer validator"));
     validatorComboBox->addItem(tr("Double validator"));

     validatorLineEdit = new QLineEdit;

     QGroupBox *alignmentGroup = new QGroupBox(tr("Alignment"));

     QLabel *alignmentLabel = new QLabel(tr("Type:"));
     QComboBox *alignmentComboBox = new QComboBox;
     alignmentComboBox->addItem(tr("Left"));
     alignmentComboBox->addItem(tr("Centered"));
     alignmentComboBox->addItem(tr("Right"));

     alignmentLineEdit = new QLineEdit;

     QGroupBox *inputMaskGroup = new QGroupBox(tr("Input mask"));

     QLabel *inputMaskLabel = new QLabel(tr("Type:"));
     QComboBox *inputMaskComboBox = new QComboBox;
     inputMaskComboBox->addItem(tr("No mask"));
     inputMaskComboBox->addItem(tr("Phone number"));
     inputMaskComboBox->addItem(tr("ISO date"));
     inputMaskComboBox->addItem(tr("License key"));

     inputMaskLineEdit = new QLineEdit;

     QGroupBox *accessGroup = new QGroupBox(tr("Access"));

     QLabel *accessLabel = new QLabel(tr("Read-only:"));
     QComboBox *accessComboBox = new QComboBox;
     accessComboBox->addItem(tr("False"));
     accessComboBox->addItem(tr("True"));

     accessLineEdit = new QLineEdit;

     connect(echoComboBox, SIGNAL(activated(int)),
             this, SLOT(echoChanged(int)));
     connect(validatorComboBox, SIGNAL(activated(int)),
             this, SLOT(validatorChanged(int)));
     connect(alignmentComboBox, SIGNAL(activated(int)),
             this, SLOT(alignmentChanged(int)));
     connect(inputMaskComboBox, SIGNAL(activated(int)),
             this, SLOT(inputMaskChanged(int)));
     connect(accessComboBox, SIGNAL(activated(int)),
             this, SLOT(accessChanged(int)));

     QGridLayout *echoLayout = new QGridLayout;
     echoLayout->addWidget(echoLabel, 0, 0);
     echoLayout->addWidget(echoComboBox, 0, 1);
     echoLayout->addWidget(echoLineEdit, 1, 0, 1, 2);
     echoGroup->setLayout(echoLayout);

     QGridLayout *validatorLayout = new QGridLayout;
     validatorLayout->addWidget(validatorLabel, 0, 0);
     validatorLayout->addWidget(validatorComboBox, 0, 1);
     validatorLayout->addWidget(validatorLineEdit, 1, 0, 1, 2);
     validatorGroup->setLayout(validatorLayout);

     QGridLayout *alignmentLayout = new QGridLayout;
     alignmentLayout->addWidget(alignmentLabel, 0, 0);
     alignmentLayout->addWidget(alignmentComboBox, 0, 1);
     alignmentLayout->addWidget(alignmentLineEdit, 1, 0, 1, 2);
     alignmentGroup-> setLayout(alignmentLayout);

     QGridLayout *inputMaskLayout = new QGridLayout;
     inputMaskLayout->addWidget(inputMaskLabel, 0, 0);
     inputMaskLayout->addWidget(inputMaskComboBox, 0, 1);
     inputMaskLayout->addWidget(inputMaskLineEdit, 1, 0, 1, 2);
     inputMaskGroup->setLayout(inputMaskLayout);

     QGridLayout *accessLayout = new QGridLayout;
     accessLayout->addWidget(accessLabel, 0, 0);
     accessLayout->addWidget(accessComboBox, 0, 1);
     accessLayout->addWidget(accessLineEdit, 1, 0, 1, 2);
     accessGroup->setLayout(accessLayout);

     QGridLayout *layout = new QGridLayout;
     layout->addWidget(echoGroup, 0, 0);
     layout->addWidget(validatorGroup, 1, 0);
     layout->addWidget(alignmentGroup, 2, 0);
     layout->addWidget(inputMaskGroup, 0, 1);
     layout->addWidget(accessGroup, 1, 1);
     setLayout(layout);

     setWindowTitle(tr("Line Edits"));
 }

 void Window::echoChanged(int index)
 {
     switch (index) {
     case 0:
         echoLineEdit->setEchoMode(QLineEdit::Normal);
         break;
     case 1:
         echoLineEdit->setEchoMode(QLineEdit::Password);
         break;
     case 2:
         echoLineEdit->setEchoMode(QLineEdit::PasswordEchoOnEdit);
         break;
     case 3:
         echoLineEdit->setEchoMode(QLineEdit::NoEcho);
     }
 }

 void Window::validatorChanged(int index)
 {
     switch (index) {
     case 0:
         validatorLineEdit->setValidator(0);
         break;
     case 1:
         validatorLineEdit->setValidator(new QIntValidator(
             validatorLineEdit));
         break;
     case 2:
         validatorLineEdit->setValidator(new QDoubleValidator(-999.0,
             999.0, 2, validatorLineEdit));
     }

     validatorLineEdit->clear();
 }

 void Window::alignmentChanged(int index)
 {
     switch (index) {
     case 0:
         alignmentLineEdit->setAlignment(Qt::AlignLeft);
         break;
     case 1:
         alignmentLineEdit->setAlignment(Qt::AlignCenter);
         break;
     case 2:
         alignmentLineEdit->setAlignment(Qt::AlignRight);
     }
 }

 void Window::inputMaskChanged(int index)
 {
     switch (index) {
     case 0:
         inputMaskLineEdit->setInputMask("");
         break;
     case 1:
         inputMaskLineEdit->setInputMask("+99 99 99 99 99;_");
         break;
     case 2:
         inputMaskLineEdit->setInputMask("0000-00-00");
         inputMaskLineEdit->setText("00000000");
         inputMaskLineEdit->setCursorPosition(0);
         break;
     case 3:
         inputMaskLineEdit->setInputMask(">AAAAA-AAAAA-AAAAA-AAAAA-AAAAA;#");
     }
 }

 void Window::accessChanged(int index)
 {
     switch (index) {
     case 0:
         accessLineEdit->setReadOnly(false);
         break;
     case 1:
         accessLineEdit->setReadOnly(true);
     }
 }