qt4 控件

QLineEdit
QString    text () const
void    setText ( const QString & )

QTextEdit
void    setText ( const QString & )


QLCDNumber
void    display ( const QString & s )
void    display ( double num )
void    display ( int num )

QComboBox
void    addItem ( const QString & text, const QVariant & userData = QVariant() )
void    addItem ( const QIcon & icon, const QString & text, const QVariant & userData = QVariant() )
void    addItems ( const QStringList & texts )
int    count () const
int    currentIndex () const
QString    currentText () const

    QString  str1,str2,str3;
    str1="hello1";
    str2="hello2";
    str3="hello3";
    QStringList longerList = (QStringList() << str1 << str2 << str3);
    ui->comboBox->addItems(longerList);

QProgressBar

    ui->progressBar->setMaximum(totalBytes); //最大值
    ui->progressBar->setValue(bytesRead);  //当前值

QCheckBox

void MainWindow::on_pushButton_clicked()
{
    bool bl=ui->checkBox->checkState();
     ui->checkBox->setChecked(!bl);
}

item widgets(item based)**************************************************************************************************************************************************
item based顾名思义就是用item为widgets赋值，所以要先创建item对象

QListWidget         refer to help

    QString  str1,str2,str3;
    str1="hello1";
    str2="hello2";
    str3="hello3";
    QStringList longerList = (QStringList() << str1 << str2 << str3);
    ui->listWidget->addItems(longerList);

    new QListWidgetItem(tr("Oak"), ui->listWidget);
    new QListWidgetItem(tr("Fir"), ui->listWidget);
    new QListWidgetItem(tr("Pine"), ui->listWidget);

       QListWidgetItem *newItem = new QListWidgetItem;
       newItem->setText("itemText");
       ui->listWidget->insertItem(0, newItem);
       //插入到第2行

QTreeWidget      refer to help

void MainWindow::on_pushButton_2_clicked()
{
    QTreeWidgetItem *item = new QTreeWidgetItem;
    item->setText(0,"hello");
    ui->treeWidget->insertTopLevelItem(0, item);
    //从第0项开始插入，从0算起
    //ui->treeWidget->addTopLevelItem(item);
    //追加在最后一项
    ui->treeWidget->setHeaderLabel("hello");

}

void MainWindow::on_pushButton_clicked()
{
    ui->treeWidget->setColumnCount(2);
    //设置为两列
    QList<QTreeWidgetItem *> items;
    for (int i = 0; i < 10; ++i)
        items.append(new QTreeWidgetItem((QTreeWidget*)0, QStringList(QString("item: %1").arg(i))));
    ui->treeWidget->insertTopLevelItems(0, items);
   //ui->treeWidget->addTopLevelItems(items);
}

item widgets(item based)**************************************************************************************************************************************************


item views(model based)**************************************************************************************************************************************************
model based顾名思义就是用model 为views赋值，所以要先创建model 对象
QTableView
ui->tableView->setModel(model);
qt4 数据库操作---------tableView

item views(model based)**************************************************************************************************************************************************