设计模式(5)-装饰模式(Decorator) (四)

QLogin::QLogin()
{
managerLabel = new QLabel(tr("&Manager:"));
QLineEdit *_managerEdit = new QLineEdit;
managerEdit = new QLineEditWithIM(_managerEdit);
managerEdit->installIM();
managerLabel->setBuddy(managerEdit);

passwdLabel = new QLabel(tr("&Passwd:"));
QLineEdit *_passwdEdit = new QLineEdit;
passwdEdit = new QLineEditWithIM(_passwdEdit);
passwdEdit->installIM();
passwdEdit->setEchoMode(QLineEdit::Password);
passwdLabel->setBuddy(passwdEdit);

okButton = new QPushButton(tr("&Login"));
cancelButton = new QPushButton("&Cancel");

okButton->setDefault(true);

buttonBox = new QDialogButtonBox;
buttonBox->addButton(okButton, QDialogButtonBox::ActionRole);
buttonBox->addButton(cancelButton, QDialogButtonBox::AcceptRole);

connect(okButton, SIGNAL(clicked()), this, SLOT(login()));
connect(cancelButton, SIGNAL(clicked()), this, SLOT(cancel()));

QHBoxLayout *topLayout = new QHBoxLayout;
topLayout->addWidget(managerLabel);
topLayout->addWidget(managerEdit);

QHBoxLayout *midLayout = new QHBoxLayout;
midLayout->addWidget(passwdLabel);
midLayout->addWidget(passwdEdit);

QVBoxLayout *mainLayout = new QVBoxLayout;
mainLayout->addLayout(topLayout);
mainLayout->addLayout(midLayout);
mainLayout->addWidget(buttonBox);
mainLayout->setMargin(20);
setLayout(mainLayout);
managerEdit->setFocus();

QIcon icon;
icon.addFile(QString::fromUtf8(":/new/main/picture/logo.png"), QSize(), QIcon::Normal, QIcon::Off);
setWindowIcon(icon);
setWindowTitle("Login");
}

QLogin::~QLogin()
{
qDebug()<<"destruct login";
delete managerLabel;
delete managerEdit;
delete passwdLabel;
delete passwdEdit;
delete okButton;
delete cancelButton;
}

/*
* Name : void login()
* Type : slot
* Func : login when authorize
* In : Null
* Out : Null
*/
void QLogin::login()
{
qDebug()<text();
qDebug()<text();
}

/*
* Name : void cancel()
* Type : slot
* Func : cancel login
* In : Null
* Out : Null
*/
void QLogin::cancel()
{
managerEdit->clear();
passwdEdit->clear();
close();
}

【分析】

(1) 与模板模式的关键区别在于，QLineEditWithIM引用了QLineEdit对象；

(2) 模板模式调用的代码为

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QLineEditWithIM *managerEdit;
managerEdit = new QLineEditWithIM;
QLineEditWithIM *managerEdit;
managerEdit = new QLineEditWit