Display xml on qlabel

jss193

Hello,

Im trying to display coordinates file into a qlabel from xml file :

$MOL



  6  6  0  0  0  0  0  0  0  0999 V2000
   -0.7145    0.4125    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0
   -0.7145   -0.4125    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0
    0.0000   -0.8250    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0
    0.7145   -0.4125    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0
    0.7145    0.4125    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0
    0.0000    0.8250    0.0000 C   0  0  0  0  0  0  0  0  0  0  0  0
  1  2  2  0        0
  2  3  1  0        0
  3  4  2  0        0
  4  5  1  0        0
  5  6  2  0        0
  6  1  1  0        0
M  END

From this I want to see a molecule, could someone give me an idea about how to do this from file into a qlabel??

Thank you very much

SGaist

Hi,

I don't want to nitpick but this is not XML at all.

Do you mean, you want to draw some sort of molecule based on this content ?

jss193

Yes, thats exactly what I wish, to display it on a qlabel, is it possible??

Thank you for your help

SGaist

You'll have to start by painting on a QPixmap first.

mrjj

Hi
Here is a sample of drawing on pixmap and show in a label.

int GetBarHeight(int MAX) {
  return rand() % (MAX-5)+5;
}

void MainWindow::on_pushButton_released() {
  int h = ui->label->height();
  int w = ui->label->width();
  QPixmap pix(w, h);
  QPainter paint(&pix);
  pix.fill( Qt::white );
  paint.setPen(QColor(0, 0, 0, 255));
  int y = 0;
  int x = 0;
  int bw = 10; // bar width
  for (int barcount = 0; barcount < 12; ++barcount) {
    paint.setBrush(QColor(255-x, 34+x, 255, 255));
    paint.drawRect(x, h - GetBarHeight(h),  bw, h );
    x += bw + 4;
  }
  paint.end();
  ui->label->setPixmap(pix);
}

alt text

However, to draw a molecule, you have to read that format correctly. Is it your own format or
something you found/got from another source?
It sounds a bit like https://fileinfo.com/extension/mol
which is used to describe something like
alt text
It comes in various version and contains heaps of information.
What exactly do you want to draw ?

jss193

Thats exactly what I want, but Im not sure about how to display it, creating a qpixmap object from that file?

I want to paste the code and the program to display the molecule automatically.

So grateful for your help

mrjj

@jss193
Hi
Well first step is to understand the format
alt text

Have you worked with this before?

mrjj

Hi
Just as update if someone finds this later.

Poster found a library http://openbabel.org/wiki/Main_Page
that can read this format and it turned out it can also export it as SVG image format.

QString smiles = ui->textEdit->toPlainText(); // this is input
string smi1 = smiles.toUtf8().constData();
OpenBabel::OBConversion conv;
conv.SetInAndOutFormats("smi","svg");
OpenBabel::OBMol mol;
conv.ReadString(&mol,smi1);
conv.WriteFile(&mol,"/path/jsfbn.svg");

and we rendered it at the wanted size and displayed in a label.

void setSVG(QLabel *label, QString FileName, int width, int height)
{
QSvgRenderer render(FileName);
render.setViewBox(QRect(0, 0, width, height));
QPixmap pix(QSize(width, height));
pix.fill(Qt::white);
QPainter p(&pix);
render.render(&p, QRect(0, 0, width, height));
label->setPixmap(pix);
label->update();

}

void MainWindow::showEvent(QShowEvent *event)
{
setSVG(ui->label, "e:/Bi0.svg", ui->label->width(), ui->label->height());
}

Just asking QLabel to show it, would scale oddly. so we used QSvgRenderer directly.