Display values inside a JList -

Question

I have a method that returns a HashMap, and is defined as follows;

public HashMap<Integer, Animal> allAnimal(){

      return returnsAHashMap;
   }

Animal will have the following values in its class:

public Animal{

int animalID;
String animalName;

// i have declared getters/setters
}

I have a GUI screen which has a JList and it's defined as:

l = new JList();
l.setModel(new AbstractListModel() {

        String[] v = new String[] {"animal id 1", "2", "3"};
        public int getSize() {
            return v.length;
        }
        public Object getElementAt(int index) {
            return v[index];
        }
    });

What I want to do is to display the AnimalID's in the JList. I need to find a way to call the allAnimal() method and display all its Animal Id's in the JList. How can i do this ?

vishal_aim · Accepted Answer · 2012-12-10T11:16:06.397

1

you can try:

public int getSize() {
    return allAnimal().size();
}
public Object getElementAt(int index) {
    return allAnimal().keySet().toArray()[index];
}

or can try:

        String[] v = null;
        v = allAnimals().keySet().toArray(v);
        public int getSize() {
            return v.length;
        }
        public Object getElementAt(int index) {
            return v[index];
        }

edited Dec 10 '12 at 11:16

answered Dec 10 '12 at 11:02

vishal_aim

7,636
1
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Consider re-factoring the invocation of `toArray()` to avoid repeated calls. – trashgod Dec 10 '12 at 11:09
But, how could i replace this line ` String[] v = new String[] {"animal id 1", "2", "3"}; With all the Animal Id's ? ` – Sharon Watinsan Dec 10 '12 at 11:10
@trashgod Like how he has done in the post or is there some other way to do it ? – Sharon Watinsan Dec 10 '12 at 11:11
Thank you.Is there a way, i could get the selected Value in the JList ? – Sharon Watinsan Dec 10 '12 at 11:17
I think you can get selected index easily, then you can get selected Id (for example using `getElementAt()`), then using allAnimals map, you can get value by `map.get(id)` method(if this is what you asked) – vishal_aim Dec 10 '12 at 11:21

score 1 · Answer 2 · edited May 23 '17 at 10:24

1

Your AbstractListModel is anonymous, so first promote it to a named class, e.g. MyListModel. Then add a method to MyListModel that either accepts a Map or calls allAnimal() to obtain one. Once you have a reference to the Map in your model, you can convert the keySet to an array, as shown here, and use the keys to get() each Map entry in getElementAt(). Optionally, sort the array using Arrays.sort().

edited May 23 '17 at 10:24

Community

1
1

answered Dec 10 '12 at 11:03

trashgod

203,806
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1,045

It's not clear what your keys represent; you may be better off iterating over the `entrySet()`. Please edit your question to include an [sscce](http://sscce.org/) that shows a _small_ number of typical `Map` entries. – trashgod Dec 10 '12 at 11:16

Display values inside a JList -

2 Answers2