How add and paint controls to widget?

[AndrzejB]

I have CodeEditor derived from QPlainTextEdit, it has sidebar with line numbers.
I am trying also add searchBar on top.

class CodeEditor : public QPlainTextEdit {
...
   SearchBar *searchBar;
  void updateSearchBarGeometry();
   void updateSearchBarArea(const QRect &rect, int dy);
...
  void searchBarPaintEvent(QPaintEvent *event);
...
}
CodeEditor::CodeEditor(QString path) : path(std::move(path)),
                        highlighter(new KSyntaxHighlighting::SyntaxHighlighter(document())),
                        searchBar(new SearchBar(this)),
                        sideBar(new CodeEditorSidebar(this)){
connect(this, &CodeEditor::updateRequest, this, &CodeEditor::updateSearchBarArea);
....
void CodeEditor::updateSearchBarGeometry() {
    const auto r = rect();
    searchBar->setGeometry(QRect(r.left(), r.top(), r.width(), 20));
}

void CodeEditor::updateSearchBarArea(const QRect &rect, int dy)
{
    if (dy) {
        searchBar->scroll(0, dy);
    } else {
        searchBar->update(0, rect.y(), rect.width(), 20);
    }
}
void CodeEditor::searchBarPaintEvent(QPaintEvent *event) {
    QPainter painter(searchBar);
    QRect r = event->rect();
    painter.fillRect(r, Qt::red);
}

class SearchBar : public QWidget {
    CodeEditor *codeEditor;
public:
    explicit SearchBar(CodeEditor *editor);
    QSize sizeHint() const override;
protected:
    void paintEvent(QPaintEvent *event) override;
};
#include "SearchBar.h"
#include "CodeEditor.h"

SearchBar::SearchBar(CodeEditor *editor)
        : QWidget(editor)
        , codeEditor(editor)
{
}

QSize SearchBar::sizeHint() const {
    return QSize(0, 20);
}

void SearchBar::paintEvent(QPaintEvent *event) {
    codeEditor->searchBarPaintEvent(event);
}

It draws correct width red bar.
Next, I want add one-line or text control , also add toolbar/coolbar with icons.
How add? How paint not by QPainter but paint these controls?
How enable focus on this bar?

[AndrzejB]

My solution:
instead add to tabWidget widget derived from PlainTextEdit, widget will group widgets:

• QPlainTextEdit
• sidebar
• searchbar

   plainEdit = new PlainTextEdit(this);
   sideBar = new CodeEditorSidebar(this);
   auto *hLayout = new QHBoxLayout;
    hLayout->setContentsMargins(0,0,0,0);
    hLayout->setSpacing(0);
    hLayout->addWidget(sideBar);
    hLayout->addWidget(plainEdit);
    setLayout(hLayout);

PlainTextEdit is instead QPlainTextEdit, because sideBar needs methods, which are protected:

class PlainTextEdit : public QPlainTextEdit {
public:
    explicit PlainTextEdit(QWidget *parent = nullptr): QPlainTextEdit(parent){};
    QTextBlock firstVisibleBlock_pub() {
        return QPlainTextEdit::firstVisibleBlock();
    }
    QRectF blockBoundingGeometry_pub(const QTextBlock &block) const {
        return QPlainTextEdit::blockBoundingGeometry(block);
    }
    QPointF contentOffset_pub() const {
        return QPlainTextEdit::contentOffset();
    }
    QRectF blockBoundingRect_pub(const QTextBlock &block) const {
        return QPlainTextEdit::blockBoundingRect(block);
    }
    virtual void resizeEvent(QResizeEvent *e) override {
        return QPlainTextEdit::resizeEvent(e);
    }
};

[mrjj]

@AndrzejB
Hi
Since SearchBar is QWidget, you can insert a layout to it and then insert any other widget you wish.

[mpergand]

First of all, I strongly recommand you to study Qt Widgets - Application Example

You have to start with QMainWindow as your base class, then you will be able to add a tool bar with a search bar easily.

From the Qt example:

MainWindow::MainWindow()
    : textEdit(new QPlainTextEdit)
{
    setCentralWidget(textEdit);

You have to replace textEdit with codeEditor:

MainWindow::MainWindow()
    : codeEditor(new CodeEditor)
{
    setCentralWidget(codeEditor);

[AndrzejB]

I see Qt/Examples/Qt-5.15.2/uitools/
how to use
Qt/5.15.2/Src/qttools/src/shared/findwidget/
?

[mrjj]

/qttools/src/shared/findwidget/

Hi
The ItemViewFindWidget ?

[AndrzejB]

My solution:
instead add to tabWidget widget derived from PlainTextEdit, widget will group widgets:

• QPlainTextEdit
• sidebar
• searchbar

   plainEdit = new PlainTextEdit(this);
   sideBar = new CodeEditorSidebar(this);
   auto *hLayout = new QHBoxLayout;
    hLayout->setContentsMargins(0,0,0,0);
    hLayout->setSpacing(0);
    hLayout->addWidget(sideBar);
    hLayout->addWidget(plainEdit);
    setLayout(hLayout);

PlainTextEdit is instead QPlainTextEdit, because sideBar needs methods, which are protected:

class PlainTextEdit : public QPlainTextEdit {
public:
    explicit PlainTextEdit(QWidget *parent = nullptr): QPlainTextEdit(parent){};
    QTextBlock firstVisibleBlock_pub() {
        return QPlainTextEdit::firstVisibleBlock();
    }
    QRectF blockBoundingGeometry_pub(const QTextBlock &block) const {
        return QPlainTextEdit::blockBoundingGeometry(block);
    }
    QPointF contentOffset_pub() const {
        return QPlainTextEdit::contentOffset();
    }
    QRectF blockBoundingRect_pub(const QTextBlock &block) const {
        return QPlainTextEdit::blockBoundingRect(block);
    }
    virtual void resizeEvent(QResizeEvent *e) override {
        return QPlainTextEdit::resizeEvent(e);
    }
};