I have an ArrayList that i want to convert to an ArrayList

Question

I have an ArrayList<JCheckBox> that i want to convert to an ArrayList<String>

First I do like this. I get all my titles from a file and put them into a new ArrayList. Afterwords I make a new JCheckBox Array that contains all the Strings from the StringArray.

ArrayList<String> titler = new ArrayList<String>();
titler.addAll(FileToArray.getName());

ArrayList<JCheckBox> filmListe = new ArrayList<JCheckBox>();
for(String titel:titler){
    filmListe.add(new JCheckBox(titel));
}
for(JCheckBox checkbox:filmListe){
    CenterCenter.add(checkbox);
}

This is what I am trying to do: First I make a new ArrayList (still in the JCheckBox format), that contains alle the selected Checkboxes. Afterwords I want to add the to a new ArrayList in a String format.

The main problem is italicized (with **):

ArrayList<JCheckBox> selectedBoxes = new ArrayList<JCheckBox>();

for(JCheckBox checkbox: filmListe){
    if (checkbox.isSelected()){
        selectedBoxes.add(checkbox);
    }

ArrayList<String> titlesArr = new ArrayList<String>();
for(JCheckBox titel:selectedBoxes){ 
    *titlesArr.add(titel);*
}

A lot of code and text for a little problem! But I really appreciate your help! :)

I'm not sure I understand what you're trying to achieve.. – mre Nov 30 '11 at 13:14 — mre, Nov 30 '11 at 13:14

score 4 · Answer 1 · answered Nov 30 '11 at 13:15

4

You can't add a JCheckBox to a List<String>, the types JCheckBox and String are incompatibles.

I guess you want to add the text of the check box into your list, so you have to retrieve it manually, using:

titlesArr.add(titel.getText());

answered Nov 30 '11 at 13:15

Vivien Barousse

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Óscar López · Answer 2 · 2011-11-30T13:36:38.987

1

Try this:

ArrayList<String> titlesArr = new ArrayList<String>();
for(JCheckBox checkbox: filmListe)
    if (checkbox.isSelected())
        titlesArr.add(checkbox.getText());

Now titlesArr contains what you wanted.

edited Nov 30 '11 at 13:36

answered Nov 30 '11 at 13:29

Óscar López

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Using `toString` on an object in this way is a very bad idea, as you depend on its implementation, which is only usually supposed to be used for debugging. In your case, calling `toString` on a `JCheckBox` would result in a horrible output like "javax.swing.JCheckBox[,0,0,0x0,invalid,alignmentX=0.0,alignmentY=0......" – BoffinBrain Nov 30 '11 at 13:34
Fixed. Mind telling constructive comments like that, *before* downvoting? – Óscar López Nov 30 '11 at 13:37

score 1 · Accepted Answer · answered Nov 30 '11 at 13:32

Assuming the checkbox's label is exactly the same as what you originally had in your list of titles, just use the checkbox's getText method (which gets the String label). You don't need to make a separate list of checkboxes that are checked - just put an if-block inside your first loop like this:

    ArrayList<String> titlesArr = new ArrayList<String>(filmListe.size());

    for (JCheckBox checkbox : filmListe) {
        if (checkbox.isSelected()) {
            titlesArr.add(checkbox.getText());
        }
    }

Thanks a lot! I've been starring at this program for too long. :) — Strammefar, Nov 30 '11 at 13:36

I have an ArrayList that i want to convert to an ArrayList

3 Answers3