Getting information about the certain object by clicking the certain image

Question

I made the following class which contains information about users - name, age photo.

public class User{

private int age;
private String name;
ImageIcon icon;
JLabel image;

public int getAge() {
return age;
}


public String getName() {
return name;
}


public User(){
this.age = 0;
this.name = "";
}


public User(int age, String name){
this.age = age;
this.name = name;
icon = new ImageIcon(name + ".jpg");
image = new JLabel(icon, JLabel.Center);
}


}

I want to create the set of images with users' faces on JPanel. I want to get details of each user after clicking on his photo. So I put this code in the main class:

MouseListener myClick = new MouseListener(){

      @Override
      public void mouseClicked(MouseEvent e)
      {
      User selected = new User();   
      selected.image = (JLabel) e.getComponent(); 
      System.out.println(selected.getAge() + " " + selected.getName());

      }
};

and

User[] users = new User[32];
  for (int i = 0; i < 32; i++)
       { 
       panel.add(users[i].image);
       users[i].image.addMouseListener(myClick);
       }

I know- it is totally wrong. I cannot obtain data about the certain user, because I get values from "selected", which contains only JLabel with image (no values for age or name). What should I do to get the name and age of the certain user?

Display the user icons in a `JList` that contains a collection of users. When an item (icon) is selected, show the details of that user. For better help sooner, post a [MCTaRE](http://stackoverflow.com/help/mcve) (Minimal Complete Tested and Readable Example). One way to get image(s) for an example is to hot-link to the images seen in [this answer](http://stackoverflow.com/a/19209651/418556). — Andrew Thompson, Mar 20 '14 at 12:59

score 1 · Answer 1 · answered Mar 20 '14 at 15:11

Not an answer to the question but:

The constructor of a class, by convention, is defined before the methods of the class.
Why did you create a User class with methods getName() and getAge() but you did not define a getImage() method? Be consistent! You should not access variables directly and should define a "getter" method when you want to access data from a class.

Learn from examples and don't make up your own standards.

To follow up on Andrew's comment, you should create a custom renderer to display the Icon from the User class in a JList. Read the section from the Swing tutorial on Writing a Custom Cell Renderer for more information and an example of displaying an Icon. The example uses a JComboBox, but the concept is the same for a JList.

Then you can use a ListSelectionListener to handle selections of the image. This a better approach because this will work when the user uses the mouse or the keyboard.

score 0 · Answer 2 · answered Mar 20 '14 at 12:57

0

I had a similiar issue with a game I'm working on, and I made a tilePane class. The TilePane class extends a JPanel and has fields for name, age, photo, etc (or just contains a user field). When a photo is clicked, get the parent tilePane, and then get the tilePane's appropriate field. Here's a snippet of my code:

public void mouseClick(MouseEvent e) {
...
    } else if (e.getSource() instanceof TilePane) {
                TilePane clickPane = (TilePane) e.getSource();
...

answered Mar 20 '14 at 12:57

iceburg

53
2
10

I cannot import TilePane from javafx.scene.layout.TilePane. I am using Netbeans Java - If I would like to use Netbeans JavaFX, I would have to create new project. I don't want to do everything from scratch. – Calm Mar 20 '14 at 14:37
@Calm I'm not using a JavaFX object; I actually made up my own TilePane class, you can make whatever new class you like, then have it extend a jpanel and attach a mouse listener to it, so it fires your mouse listener and provide's itself as a source. Then you have the object that contains your other data. :) – iceburg Mar 20 '14 at 21:04

score 0 · Accepted Answer · answered Mar 20 '14 at 15:28

There are several ways of achieving what you want to do. (I'm not entirely sure what this is, but I'm sure that there are several ways ;-)).

One interesting question might be who determines the bounds of the images / labels. Are they put into a panel that has a certain layout? When they are, for example, contained in a panel with a GridLayout then you can just compute the index of the image based on the "grid cell" that corresponds to a certain mouse position on the panel. If they are positioned freely (on a panel with null layout), then you might create a simple map like

class ImageMap<T> 
{
    private final Map<Rectangle2D, T> map;

    ImageMap()
    {
        map = new LinkedHashMap<Rectangle2D, T>();
    }

    public T get(double x, double y)
    {
        for (Entry<Rectangle2D, T> entry : map.entrySet())
        {
            Rectangle2D key = entry.getKey();
            if (key.contains(new Point2D.Double(x,y)))
            {
                return entry.getValue();
            }
        }
        return null;
    }

    void setBounds(T t, Rectangle2D r)
    {
        Rectangle2D copy = new Rectangle2D.Double(
            r.getX(), r.getY(), r.getWidth(), r.getHeight());
        map.put(copy, t);
    }
}

Then you can fill this map with the information from the users:

ImageMap<User> map = new ImageMap<User>();

List<User> users = ...;
for (User user : users)
{
    map.setBounds(user, user.getImage().getBounds());
}

And when you receive a mouse event, you can query this

    MouseEvent e = ...;
    User user = map.get(e.getX(), e.getY());

But whether this is appropriate really depends on your use-case. Maybe a JList with an appropriate CellRenderer would better suit your needs.

Getting information about the certain object by clicking the certain image

3 Answers3