[Interest] resizable QTextEdit

[Igor Mironchik]

Hi again,

If you want to be able to shrink the width too, you can do something 
similar to:


#include <QTextEdit>
#include <QHBoxLayout>
#include <QLabel>
#include <QWidget>
#include <QApplication>
#include <QPainter>
#include <QVBoxLayout>
#include <QMouseEvent>
#include <QResizeEvent>
#include <QFrame>


class Text;

class Corner
     :    public QWidget
{
public:
     Corner( Text * parent );

     virtual ~Corner();

     QSize sizeHint() const Q_DECL_OVERRIDE;

protected:
     void paintEvent( QPaintEvent * ) Q_DECL_OVERRIDE;

     void mousePressEvent( QMouseEvent * e ) Q_DECL_OVERRIDE;

     void mouseReleaseEvent( QMouseEvent * e ) Q_DECL_OVERRIDE;

     void mouseMoveEvent( QMouseEvent * e ) Q_DECL_OVERRIDE;

private:
     Text * m_toResize;
     QPoint m_pos;
     bool m_pressed;
};

class Text
     :    public QTextEdit
{
public:
     Text( QWidget * parent, QLayout * layout );

     virtual ~Text();

     void addSize( const QSize & size );

     QSize sizeHint() const Q_DECL_OVERRIDE;

protected:
     void resizeEvent( QResizeEvent * e ) Q_DECL_OVERRIDE;

private:
     Corner * m_corner;
     QSize m_size;
     QLayout * m_layout;
};

Corner::Corner( Text * parent )
     :    QWidget( parent )
     ,    m_toResize( parent )
     ,    m_pressed( false )
{
}

Corner::~Corner()
{
}

QSize
Corner::sizeHint() const
{
     return QSize( 10, 10 );
}

void
Corner::paintEvent( QPaintEvent * )
{
     QPainter p( this );
     p.setPen( Qt::red );
     p.setBrush( Qt::red );

     p.drawRect( rect() );
}

void
Corner::mousePressEvent( QMouseEvent * e )
{
     if( e->button() == Qt::LeftButton )
     {
         m_pos = e->pos();
         m_pressed = true;
     }

     e->accept();
}

void
Corner::mouseReleaseEvent( QMouseEvent * e )
{
     if( e->button() == Qt::LeftButton )
         m_pressed = false;

     e->accept();
}

void
Corner::mouseMoveEvent( QMouseEvent * e )
{
     if( m_pressed )
     {
         const QPoint delta = e->pos() - m_pos;

         m_toResize->addSize( QSize( delta.x(), delta.y() ) );
     }

     e->accept();
}

Text::Text( QWidget * parent, QLayout * layout )
     :    QTextEdit( parent )
     ,    m_corner( new Corner( this ) )
     ,    m_size( QTextEdit::sizeHint() )
     ,    m_layout( layout )
{
     m_corner->move( width() - m_corner->width(),
         height() - m_corner->height() );
}

Text::~Text()
{
}

void
Text::addSize( const QSize & size )
{
     setSizePolicy( QSizePolicy::Fixed, QSizePolicy::Fixed );

     m_size = QSize( m_size.width() + size.width(), m_size.height() + 
size.height() );

     updateGeometry();
}

QSize
Text::sizeHint() const
{
     return m_size;
}

void
Text::resizeEvent( QResizeEvent * e )
{
     m_corner->move( e->size().width() - m_corner->width(),
         e->size().height() - m_corner->height() );

     m_size = e->size();

     e->accept();
}


class Form
     :    public QWidget
{
public:
     Form()
     {
         QVBoxLayout * v = new QVBoxLayout( this );
         QFrame * f = new QFrame( this );
         f->setFrameStyle( QFrame::Panel | QFrame::Sunken );
         QHBoxLayout * h = new QHBoxLayout( f );
         v->addWidget( f );
         QLabel * label = new QLabel( "Resizeable Text Field", f );
         label->setSizePolicy( QSizePolicy::Fixed, QSizePolicy::Fixed );
         h->addWidget( label );
         Text * text = new Text( f, v );
         h->addWidget( text );
         QSpacerItem * s = new QSpacerItem( 10, 10, QSizePolicy::Fixed,
             QSizePolicy::Expanding );
         v->addItem( s );

         resize( 800, 800 );
     }

     virtual ~Form()
     {
     }
};

int main( int argc, char ** argv )
{
     QApplication app( argc, argv );

     Form f;
     f.show();

     return app.exec();
}


On 15.04.2018 11:53, Alexander Semke wrote:
> On Freitag, 13. April 2018 10:22:14 CEST Igor Mironchik wrote:
>> Something like this?
>> [...]
> Thanks Igor, I've got the idea. The resize works fine now but I have the
> problem with the layout of the parent widget being not updated. My text edit
> widget is embedded into a QFrame with a vertical layout. After the manual
> resize I need the layout(s) and the sizes/positions of this frame and of all
> the other widgets frame's parent to be adjusted to the new size of the text
> edit.
>
> https://imgur.com/a/eV2Fj - here the height of the text edit widget was made
> smaller but the QFrame widget where the text edit is placed in a vertical
> layout was not resized. I'm calling frame->layout()->activate() to trigger the
> recalculation but this doesn't lead to the desired effect...  Do I new to
> resize the frame widget here manually or are there any other methods to
> update/recalculate the layout?
>
>