【Qt】Qt之自定义界面（QMessageBox）【转】

简述

通过前几节的自定义窗体的学习，我们可以很容易的写出一套属于自己风格的界面框架，通用于各种窗体，比如：QWidget、QDialog、QMainWindow。

大多数窗体的实现都是采用控件堆积来完成的，只要思路清晰，再复杂的界面实现起来都游刃有余。下面我来列举一个由QMessageBox扩展的提示框-根据其源码实现思路来实现！

简述
效果
自定义提示框
实现
接口说明
二次封装
使用方式

源码学习

效果

自定义提示框

实现

message_box.h

#ifndef MESSAGE_BOX
#define MESSAGE_BOX

#include <QMessageBox>
#include <QDialogButtonBox>
#include <QGridLayout>
#include "custom_window.h"

class QLabel;

class MessageBox : public CustomWindow
{
Q_OBJECT

public:
explicit MessageBox(QWidget *parent = 0, const QString &title = tr("Tip"), const QString &text = "",
QMessageBox::StandardButtons buttons = QMessageBox::Ok, QMessageBox::StandardButton defaultButton = QMessageBox::Ok);
~MessageBox();
QAbstractButton *clickedButton() const;
QMessageBox::StandardButton standardButton(QAbstractButton *button) const;
// 设置默认按钮
void setDefaultButton(QPushButton *button);
void setDefaultButton(QMessageBox::StandardButton button);
// 设置窗体标题
void setTitle(const QString &title);
// 设置提示信息
void setText(const QString &text);
// 设置窗体图标
void setIcon(const QString &icon);
// 添加控件-替换提示信息所在的QLabel
void addWidget(QWidget *pWidget);

protected:
// 多语言翻译
void changeEvent(QEvent *event);

private slots:
void onButtonClicked(QAbstractButton *button);

private:
void translateUI();
int execReturnCode(QAbstractButton *button);

private:
QLabel *m_pIconLabel;
QLabel *m_pLabel;
QGridLayout *m_pGridLayout;
QDialogButtonBox *m_pButtonBox;
QAbstractButton *m_pClickedButton;
QAbstractButton *m_pDefaultButton;
};

message_box.cpp

#include <QLabel>
#include <QPushButton>
#include <QMessageBox>
#include <QCheckBox>
#include <QHBoxLayout>
#include <QEvent>
#include <QApplication>
#include "message_box.h"

MessageBox::MessageBox(QWidget *parent, const QString &title, const QString &text,
QMessageBox::StandardButtons buttons, QMessageBox::StandardButton defaultButton)
: CustomWindow(parent)
{
setWindowIcon(QIcon(":/Images/logo"));
setWindowTitle(title);
setMinimumSize(300, 130);
setMinimizeVisible(false);
setMaximizeVisible(false);
setWidgetResizable(false);

m_pButtonBox = new QDialogButtonBox(this);
m_pButtonBox->setStandardButtons(QDialogButtonBox::StandardButtons(int(buttons)));
setDefaultButton(defaultButton);

QPushButton *pYesButton = m_pButtonBox->button(QDialogButtonBox::Yes);
if (pYesButton != NULL)
{
pYesButton->setObjectName("blueButton");
pYesButton->setStyle(QApplication::style());
}

m_pIconLabel = new QLabel(this);
m_pLabel = new QLabel(this);

QPixmap pixmap(":/Images/information");
m_pIconLabel->setPixmap(pixmap);
m_pIconLabel->setFixedSize(35, 35);
m_pIconLabel->setScaledContents(true);

m_pLabel->setAlignment(Qt::AlignLeft | Qt::AlignVCenter);
m_pLabel->setObjectName("whiteLabel");
m_pLabel->setOpenExternalLinks(true);
m_pLabel->setText(text);

m_pGridLayout = new QGridLayout();
m_pGridLayout->addWidget(m_pIconLabel, 0, 0, 2, 1, Qt::AlignTop);
m_pGridLayout->addWidget(m_pLabel, 0, 1, 2, 1);
m_pGridLayout->addWidget(m_pButtonBox, m_pGridLayout->rowCount(), 0, 1, m_pGridLayout->columnCount());
m_pGridLayout->setSizeConstraint(QLayout::SetNoConstraint);
m_pGridLayout->setHorizontalSpacing(10);
m_pGridLayout->setVerticalSpacing(10);
m_pGridLayout->setContentsMargins(10, 10, 10, 10);
m_pLayout->addLayout(m_pGridLayout);

translateUI();

connect(m_pButtonBox, SIGNAL(clicked(QAbstractButton*)), this, SLOT(onButtonClicked(QAbstractButton*)));
}

MessageBox::~MessageBox()
{

}

void MessageBox::changeEvent(QEvent *event)
{
switch (event->type())
{
case QEvent::LanguageChange:
translateUI();
break;
default:
CustomWindow::changeEvent(event);
}
}

void MessageBox::translateUI()
{
QPushButton *pYesButton = m_pButtonBox->button(QDialogButtonBox::Yes);
if (pYesButton != NULL)
pYesButton->setText(tr("Yes"));

QPushButton *pNoButton = m_pButtonBox->button(QDialogButtonBox::No);
if (pNoButton != NULL)
pNoButton->setText(tr("No"));

QPushButton *pOkButton = m_pButtonBox->button(QDialogButtonBox::Ok);
if (pOkButton != NULL)
pOkButton->setText(tr("Ok"));

QPushButton *pCancelButton = m_pButtonBox->button(QDialogButtonBox::Cancel);
if (pCancelButton != NULL)
pCancelButton->setText(tr("Cancel"));
}

QMessageBox::StandardButton MessageBox::standardButton(QAbstractButton *button) const
{
return (QMessageBox::StandardButton)m_pButtonBox->standardButton(button);
}

QAbstractButton *MessageBox::clickedButton() const
{
return m_pClickedButton;
}

int MessageBox::execReturnCode(QAbstractButton *button)
{
int nResult = m_pButtonBox->standardButton(button);
return nResult;
}

void MessageBox::onButtonClicked(QAbstractButton *button)
{
m_pClickedButton = button;
done(execReturnCode(button));
}

void MessageBox::setDefaultButton(QPushButton *button)
{
if (!m_pButtonBox->buttons().contains(button))
return;
m_pDefaultButton = button;
button->setDefault(true);
button->setFocus();
}

void MessageBox::setDefaultButton(QMessageBox::StandardButton button)
{
setDefaultButton(m_pButtonBox->button(QDialogButtonBox::StandardButton(button)));
}

void MessageBox::setTitle(const QString &title)
{
setWindowTitle(title);
}

void MessageBox::setText(const QString &text)
{
m_pLabel->setText(text);
}

void MessageBox::setIcon(const QString &icon)
{
m_pIconLabel->setPixmap(QPixmap(icon));
}

void MessageBox::addWidget(QWidget *pWidget)
{
m_pLabel->hide();
m_pGridLayout->addWidget(pWidget, 0, 1, 2, 1);
}

接口说明

CustomWindow

主要对界面的无边框可拖动进行了封装

MessageBox

整体界面布局及事件处理参考了QMessageBox源码，接口包含：设置标题、提示信息、默认按钮及事件触发等操作。

二次封装

针对于各种提示框，我们可以再次进行封装，将常用的提取出来，作为全局函数来使用。

QMessageBox::StandardButton showInformation(QWidget *parent, const QString &title,
const QString &text, QMessageBox::StandardButtons buttons,
QMessageBox::StandardButton defaultButton)
{
MessageBox msgBox(parent, title, text, buttons, defaultButton);
msgBox.setIcon(":/Images/information");
if (msgBox.exec() == -1)
return QMessageBox::Cancel;
return msgBox.standardButton(msgBox.clickedButton());
}

QMessageBox::StandardButton showError(QWidget *parent, const QString &title,
const QString &text, QMessageBox::StandardButtons buttons,
QMessageBox::StandardButton defaultButton)
{
MessageBox msgBox(parent, title, text, buttons, defaultButton);
msgBox.setIcon(":/Images/error");
if (msgBox.exec() == -1)
return QMessageBox::Cancel;
return msgBox.standardButton(msgBox.clickedButton());
}

QMessageBox::StandardButton showSuccess(QWidget *parent, const QString &title,
const QString &text, QMessageBox::StandardButtons buttons,
QMessageBox::StandardButton defaultButton)
{
MessageBox msgBox(parent, title, text, buttons, defaultButton);
msgBox.setIcon(":/Images/success");
if (msgBox.exec() == -1)
return QMessageBox::Cancel;
return msgBox.standardButton(msgBox.clickedButton());
}

QMessageBox::StandardButton showQuestion(QWidget *parent, const QString &title,
const QString &text, QMessageBox::StandardButtons buttons,
QMessageBox::StandardButton defaultButton)
{
MessageBox msgBox(parent, title, text, buttons, defaultButton);
msgBox.setIcon(":/Images/question");
if (msgBox.exec() == -1)
return QMessageBox::Cancel;
return msgBox.standardButton(msgBox.clickedButton());
}

QMessageBox::StandardButton showWarning(QWidget *parent, const QString &title,
const QString &text, QMessageBox::StandardButtons buttons,
QMessageBox::StandardButton defaultButton)
{
MessageBox msgBox(parent, title, text, buttons, defaultButton);
msgBox.setIcon(":/images/warning");
if (msgBox.exec() == -1)
return QMessageBox::Cancel;
return msgBox.standardButton(msgBox.clickedButton());
}

QMessageBox::StandardButton showCritical(QWidget *parent, const QString &title,
const QString &text, QMessageBox::StandardButtons buttons,
QMessageBox::StandardButton defaultButton)
{
MessageBox msgBox(parent, title, text, buttons, defaultButton);
msgBox.setIcon(":/Images/warning");
if (msgBox.exec() == -1)
return QMessageBox::Cancel;
return msgBox.standardButton(msgBox.clickedButton());
}

QMessageBox::StandardButton showCheckBoxQuestion(QWidget *parent, const QString &title,
const QString &text, QMessageBox::StandardButtons buttons,
QMessageBox::StandardButton defaultButton)
{
MessageBox msgBox(parent, title, text, buttons, defaultButton);
msgBox.setIcon(":/Images/question");

QCheckBox *pCheckBox = new QCheckBox(&msgBox);
pCheckBox->setText(text);
msgBox.addWidget(pCheckBox);
if (msgBox.exec() == -1)
return QMessageBox::Cancel;

QMessageBox::StandardButton standardButton = msgBox.standardButton(msgBox.clickedButton());
if (standardButton == QMessageBox::Yes)
{
return pCheckBox->isChecked() ? QMessageBox::Yes : QMessageBox::No;
}
return QMessageBox::Cancel;
}

使用方式

showInformation(this, QStringLiteral("提示"), QStringLiteral("这是一个普通的提示框-Information！"));
showQuestion(this, QStringLiteral("提示"), QStringLiteral("这是一个普通的提示框-Question！"));
showSuccess(this, QStringLiteral("提示"), QStringLiteral("这是一个普通的提示框-Success！"));
showError(this, QStringLiteral("提示"), QStringLiteral("这是一个普通的提示框-Error！"));

源码学习

其实Qt中有很多自带的比较好的效果，里面用了很好的实现方式，建议安装的时候把源码download下来，随时可以研究并学习。例如：

D:\Qt\Qt5.5.1\5.5\Src\qtbase\src\widgets\dialogs

下面包含了所有关于dialog的实现-QProgressDialog、QMessageBox、QFileDialog。。。

原文作者：一去丶二三里
作者博客：去作者博客空间