Qt QScrollArea

1. brief introduction

QScrollArea Class provides a scrolling view . The scrolling area is used to display the contents of the sub components in the frame . If the widget exceeds the size of the frame , The view can provide scroll bars , So that you can see the entire area of the child widget . Subassemblies must use setWidget() Appoint .

Easy to use ：

    QLabel *imageLabel = new QLabel;
    QImage image("C:\\Users\\Desktop\\image\\1.webp");
    imageLabel->setPixmap(QPixmap::fromImage(image));

    QScrollArea *scrollArea = new QScrollArea;
    scrollArea->setBackgroundRole(QPalette::Dark);
    scrollArea->setWidget(imageLabel);

    ui->verticalLayout->addWidget(scrollArea);

 2. Common methods

QWidget *widget() const	Get the part of the scrolling area
QWidget *takeWidget()	Remove the widget from the scrolling area , And pass the ownership of the widget to the caller .
void ensureVisible(int x, int y, int xmargin = 50, int ymargin = 50)	Make sure that the contents of a certain area in the viewport are visible
void setAlignment(Qt::Alignment)	Set alignment

3. Example

  Source code ：

    QScrollArea *scrollArea = new QScrollArea;
    scrollArea->setBackgroundRole(QPalette::Dark);  // Set background color

    QWidget *widget = new QWidget;
    QVBoxLayout *layout = new QVBoxLayout;  // Set vertical layout

    widget->setLayout(layout);

    QTextEdit *t1 = new QTextEdit(widget);
    QTextEdit *t2 = new QTextEdit(widget);
    QTextEdit *t3 = new QTextEdit(widget);

    t1->setPlaceholderText("t1");
    t2->setPlaceholderText("t2");
    t3->setPlaceholderText("t3");

    t1->setFixedHeight(300);    // Set fixed height
    t2->setFixedHeight(300);
    t3->setFixedHeight(300);

    layout->addWidget(t1);
    layout->addWidget(t2);
    layout->addWidget(t3);

    scrollArea->setWidget(widget);
    ui->verticalLayout->addWidget(scrollArea);