Qt Opengl, Changing objects color

Hi,
I'm trying to do a program which includes an opengl widget on the left and a tree on the right. So when the user selects the object from the tree, The object in the left shhould be highlighted or change color or smth else u offer me to do which is easier.
I thought that changing its color would be the easiest one. But I didnot managed to succeed it.
It seems correct. I don't understand where is the mistake.
Here is my code:

Code:

---

void GLWidget::initializeGL()
{
    qglClearColor(trolltechPurple.dark());
    object = makeObject();
    glShadeModel(GL_FLAT);
    glEnable(GL_DEPTH_TEST);
    glEnable(GL_CULL_FACE);
}
 
void GLWidget::paintGL()
{
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    glLoadIdentity();
    glTranslated(0.0, 0.0, -10.0);
    glRotated(xRot / 16.0, 1.0, 0.0, 0.0);
    glRotated(yRot / 16.0, 0.0, 1.0, 0.0);
    glRotated(zRot / 16.0, 0.0, 0.0, 1.0);
    glCallList(object);
}
 
void GLWidget::resizeGL(int width, int height)
{
    int side = qMin(width, height);
    glViewport((width - side) / 2, (height - side) / 2, side, side);
 
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    glOrtho(-0.5, +0.5, +0.5, -0.5, 4.0, 15.0);
    glMatrixMode(GL_MODELVIEW);
}
void GLWidget::setHighlighted(){
	Purple = QColor::fromCmykF(0.25, 0.25, 0.20, 0.0);
	qglColor(Purple);
	//paintGL();
	//,nitializeGL();
	updateGL();
 
}

---

Plss help me :(

http://doc.trolltech.com/4.3/opengl-hellogl.html
im using this example for my base type. When I use the rotation functions in my slot function, it works. However I want to change the objects color.
There is a signal called "xRotationChanged" in the implementation of setXrotation() function. There must be a function to change the color in the same way.
But I couldn't find it, anybody can help me pls??

will anybody help me ? :(

I couldn't find anycode for at least drawing also. So I decided to use "c".
It compiles but it does not draw my objects on to the widget.
Anybody has an idea why it does not do that?
here is my c code inside "setHighligthed()" slot function:

Code:

---

glColor3f(0.5f,0.5f,1.0f);				// Set The Color To Blue One Time Only
	glBegin(GL_QUADS);					// Start Drawing Quads
		glVertex3f(-1.0f, 1.0f, 0.0f);			// Left And Up 1 Unit (Top Left)
		glVertex3f( 1.0f, 1.0f, 0.0f);			// Right And Up 1 Unit (Top Right)
		glVertex3f( 1.0f,-1.0f, 0.0f);			// Right And Down One Unit (Bottom Right)
		glVertex3f(-1.0f,-1.0f, 0.0f);			// Left And Down One Unit (Bottom Left)
	glEnd();

---