how to create a Custom list model in Java

Question

I'm trying to create list that shows contacts, each list item shows the name on a line, and the phone number on a second line, and maybe an image or icon. I was thinking of using two labels for that, but i can figure out how to use a custom list model to implement this.

My first attempt was to add a Panel object that contained the info i wanted in the list, then add it to an instance of the defualt list model, but that only turned up the class name in the list.

    DefaultListModel Clistmodel = new DefaultListModel();//
    Clistmodel.addElement(Contact);//Contact is an JPanel object
    GroupList.setModel(Clistmodel);//GroupList is the List object

this didn't work out at all then i learnt that the default list model only knows how to render strings i think, so i have to create a custom list model, or a custom ListCellRenderer, i don't really know which will solve the problem.

Answer 1

Your question asks how to create a custom list model, however, that's not what you need (I don't think) as a DefaultListModel will work nicely for you. Rather you will need to work on the renderer. You need to create a non-GUI class to hold your information that each item will display, probably your Contact class, and then create a JList that holds this in its DefaultListModel.

The key for you will be to then create a custom list cell renderer to display the information on multiple lines -- perhaps a JTextArea, or a JPanel that holds two JLabels in a GridLayout. Please understand that the renderer does not display the actual underlying components, but something more akin to a stamped image of whatever components you're trying to display, so it will not have the full behaviors available to it as the actual component would. It will take work, but the writing a renderer section of the tutorial linked to by user714965 will show you how to do this.

Please give it a try, and then if you still are stuck, come on back with your code, your errors, and your questions, and we'll be better able to give you specific help.