# How can I access object method inside other object?
**URL:** https://discourse.processing.org/t/how-can-i-access-object-method-inside-other-object/4609
**Category:** Coding Questions
**Created:** [October 18, 2018, 4:54pm UTC](https://discourse.processing.org/t/how-can-i-access-object-method-inside-other-object/4609 "2018-10-18T16:54:01Z")
**Posts on this page:** 6
**Page:** 1
### Author:  [@enonod](https://discourse.processing.org/u/enonod)
#### Post date: [October 18, 2018, 4:54pm UTC](https://discourse.processing.org/t/how-can-i-access-object-method-inside-other-object/4609/1 "2018-10-18T16:54:01Z")
Within DPanel I have added two objects, captionBar and btnClose and have called their display() methods successfully as shown in DPanel.display(). I have attempted to bring in a third object via the DPanel method addObject. However I get the message that display() does not exist… referring to the Existing\_Object.display().
The Existing\_Object has a display() method no different to the two objects within DPanel. I therefore assume that the invisibility is caused by my attempt to ‘import’ a pre-existing object to make it part of DPanel. Can anybody please explain, simply, what it is that I don’t understand. Thank you.
```auto
class DPanel {
//variable declarations
...
PFont arial14;
Object ExistingObject;
//Constructor
DPanel(int _x, int _y etc.) {
btnClose = new DButton(x, y, etc.);
captionBar = new DLabel(x, y, etc.);
}//end constructor
//Methods
void addObject(Object _Existing_Object) {
Existing_Object = _Existing_Object;
}// end addObject
void display() {
fill(0);
text(txt, etc...);
captionBar.display();
btnClose.display();
Existing_Object.display();
}// end display
}//end DPanel
```
---
### Author:  [@quark](https://discourse.processing.org/u/quark)
#### Post date: [October 18, 2018, 5:18pm UTC](https://discourse.processing.org/t/how-can-i-access-object-method-inside-other-object/4609/2 "2018-10-18T17:18:03Z")
The problem is that you have declared `ExistingObject` to be of type `Object` which is the base class for all Java and user-defined classes. So in the statment `Existing_Object.display();` will look for a display method inside the class `Object` and will not find one.
---
### Author:  [@quark](https://discourse.processing.org/u/quark)
#### Post date: [October 18, 2018, 5:33pm UTC](https://discourse.processing.org/t/how-can-i-access-object-method-inside-other-object/4609/3 "2018-10-18T17:33:24Z")
Create an Interface like this
```auto
public Interface Displayable {
public void display();
}
```
then declare the DPanel class
```auto
public class DPanel implements Displayable {
PFont arial14;
Displayable ExistingObject;
//Constructor
DPanel(int _x, int _y etc.) {
btnClose = new DButton(x, y, etc.);
captionBar = new DLabel(x, y, etc.);
}//end constructor
//Methods
void addObject(Displayable _Existing_Object) {
Existing_Object = _Existing_Object;
} // end addObject
void display() {
fill(0);
text(txt, etc…);
captionBar.display();
btnClose.display();
Existing_Object.display();
} // end display
} //end DPanel
```
All your GUI control class (e.g. DButton, DLabel etc) should also implement `Displayable`
---
### Author:  [@enonod](https://discourse.processing.org/u/enonod)
#### Post date: [October 18, 2018, 5:39pm UTC](https://discourse.processing.org/t/how-can-i-access-object-method-inside-other-object/4609/4 "2018-10-18T17:39:12Z")
Thank you for your very quick reply. I have attempted to respond via the forum but the web page is constantly blank.
Will you please be kind enough quark, to suggest what I should do instead. This is not just a mistake on my part, I actually do not know even if it is possible to add an object this way nor how.
Thank you
---
### Author:  [@quark](https://discourse.processing.org/u/quark)
#### Post date: [October 19, 2018, 7:47am UTC](https://discourse.processing.org/t/how-can-i-access-object-method-inside-other-object/4609/5 "2018-10-19T07:47:55Z")
> [@enonod](#):
>
> Will you please be kind enough quark, to suggest what I should do instead.
I have - see my second post!
---
### Author:  [@enonod](https://discourse.processing.org/u/enonod)
#### Post date: [October 19, 2018, 8:54am UTC](https://discourse.processing.org/t/how-can-i-access-object-method-inside-other-object/4609/6 "2018-10-19T08:54:41Z")
Maybe the web site goes off at night, it is back now 🙂
Many thanks quark for the introduction to something completely unknown to me. I will now play for a while and hopefully succeed