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How to know in which JTextPane the cursor is?

I have several JtextPanes and I want to create a method that set the value of a variable to the name of the TextPane which has been clicked because another methond is going to use it. There's also a button that adds a new jTextPane when the user clicks on it and I want those new TextPanes to inherit that method. Or if you know a simpler way to achieve that I'm open to read you. Let me know if you need more information or more code.
static JTextPane focus;
private void redColorActionPerformed(java.awt.event.ActionEvent evt) { //Ths is the method that works with the focus variable. It changes the color of the text in the clicked textpane.
TextEditor.cambiarColor(new java.awt.Color(255, 0, 0), focus);
}

It sound like you want to know the current Swing JTextPane component under the current mouse position? Then try to
Get current Mouse position
Point position = MouseInfo.getPointerInfo().getLocation();
Get the component under the mouse location
Component c = SwingUtilities.getDeepestComponentAt(
the-root-component,
position.getX(),
position.getY()
);
if (c instanceof JTextPane) {
// do your logic
}

getY() returning 0 upon adding a JComponent

I'm new to Swing so I read through Java tutorials and API. I've been playing around with a subclass of JComponent (DTPicture-supports drag and drop). Basically I create a panel with a GridLayout. Then I populate the panel with DTPicture objects. DTPicture has inherited getLocation(). Upon calling this however, the value is 0. When I run the GUI however, I see DTPicture objects spanning vertically. So why is getLocation returning 0?
Thanks.
Below is my code:
*everything else has been initialized, declared, implemented.
public class RackBuilderTool extends JPanel{
//maps rack slot # to DTPicture location on JPanel
public static Point[] slotIDArray = new Point[42];
public RackBuilderTool() {
super(new GridLayout(42, 1));
//DTPicture[] rackSlotArray = new DTPicture[42];
for (int i = 0; i < 42; i++) {
//add(new ComponentLabel());
DTPicture temp = new DTPicture(null);
System.out.println(add(temp).getLocation());
//address of DTPicture Component
slotIDArray[i] = temp.getLocation();
}
}

Upon calling this however, the value is 0.
The size (and location) of a component defaults to 0 when a component is created.
When I run the GUI however, I see DTPicture objects spanning vertically
The layout manager(s) are responsible for determining the size/location of a component. However, the layout manager is only invoked when you use pack() or setVisible(true) on a frame.
If you add a component to a visible frame, then you must use the revalidate() method to invoke the layout manager.
Think about it, the layout manager can't do its job until all components have been added to the panel since it will not know how to size every component. Especially in the case of a GridLayout all components are made the same size as the largest component. So how do you know what the largest component is until all components have been added? It would not be very efficient to do the layout every time a component is added.

Java Swing - Scroll Pane With Custom Graphics

I currently have the code below.
public class cRunningView extends JInternalFrame {
static final int xOffset = 30, yOffset = 30;
public cRunningView() {
// Get name;
super("RUNNING", true, // resizable
false, // closable
true, // maximizable
true);// iconifiable
System.out.println("##" + "p.getName()");
// ...Then set the window size or call pack...
setSize(500, 200);
// Set the window's location.
setLocation(xOffset * 0, yOffset * 0);
JScrollPane scrollPane = new JScrollPane();
}
}
My aim is to have a JInternalFrame with a number of buttons and a box/rectangle on half of the screen.
Within this box i want to be able to draw graphics for e.g. Draw oval from x,y to x,y.
I've tried looking at examples but see to get my self more confused than i did to begin. All my code is working e.g. Showing the main GUI window and my internal frame opening but i cant seem to find a good tutuirol/starting point to do graphics within a JScrollPane.
Please note i dont have to use a JScrollPane i just thought i would be a good idea cause it would give the graphics a border round it.
Before anyone moans about the question i think it is valid AND I DONT want the code to be given to me on a plate, i'd rather know and understand what im doing so i can advance my knowledge and be able to help others !
Do i have to make another class and do
JScrollPane myPane = JScrollPane(graphicsClass)
then do everything with paint() then or is there someway to create a graphic and do it without another class?
If i do :
JScrollPane scrollPane = new JScrollPane();
Graphics temp = scrollPane.getGraphics();
temp.setColor(new Color(1, 22, 33));
temp.fillOval(60, 0, 120, 60);
scrollPane.paint(temp);
It throws errors.
Thanks

You don't do Graphics in a scrollpane. Also, don't use the getGraphics() method to do custom painting.
Custom painting is done by overriding the paintComponent() method of a JPanel or JComponent. Then if required you can add the panel to a scrollpane and add the scrollpane to your frame. Don't forget to set the preferred size of the panel so scrolling will work.
Start by reading the Swing tutorial on Custom Painting.

Find components in Java's GUI hierarchy

With this code I am able to find what tab is selected but I need to do stuff with what is inside the tab. How do I work with the hierarchy?
EditPane.addChangeListener(new ChangeListener() {
// This method is called whenever the selected tab changes
public void stateChanged(ChangeEvent evt) {
JTabbedPane pane = (JTabbedPane)evt.getSource();
// Gets current tab
int sel = pane.getSelectedIndex();
}
});
The component that is inside the tab is a JScrollPane.

You don't need the index of the pane, you need the component selected underneath.
use getSelectedComponent() - e.g.
JTabbedPane pane = (JTabbedPane)evt.getSource();
JComponent myComponent = pane.getSelectedComponent();
To clarify your original goal, you want to manipulate the client object living in the JScrollPane. You're missing some objects.
in your JScrollPane you need to invoke getViewport().getViewportView() from the ScrollPane. (Source: http://download.oracle.com/javase/tutorial/uiswing/components/scrollpane.html )

# Dasdasd
I already checked it out but it only returns ViewPorts and ScrollBars
yes that correct, (probalby there you put JPanel) then you have to repeats your steps again, until as you will not find JPanel into ViewPort, that's possible get JComponents another way(s), but this is very good lesson for Hierarchy of JComponents
Component[] components = xxx.getComponents();
for (int i = 0, l = components.length; i < l; i++) {
if (components[i] instanceof JScrollPane) {
JScrollPane scr = (JScrollPane) components[i];
Component[] components1 = scr.getComponents();n

how to hide a text area in java swing form?

i used textarea1.setVisible(false); but still i can see the border of the text area at run time. i want the textarea to be completely invisible
Can anyone help in this issue?

It sounds like you have a Panel around your text area since setVisible(false) should definitely hide the entire component. If so, make the panel invisible. Care to post some code so we can examine and help?

You have to hide the scroll pane which your text area is sitting in. If for some reason you have no direct access to it here is the way to get it:
public static final JScrollPane getScrollPane( JComponent component ) {
Container p = component .getParent();
if (p instanceof JViewport) {
Container gp = p.getParent();
if (gp instanceof JScrollPane) {
return (JScrollPane)gp;
}
}
return null;
}

Find your textarea scrollpane, then set the visibility to false, like this:
jScrollPane4.setVisible(false);