Question

The dialogue and the array displays just fine, I just want to be able to set the static variable from the originating class within the onClick that is in a method that is in a different class. All of the try, catch and
<?> were things that I put in at the insistence of the compiler:

public class Setter
    {
    public void myList(Context context, Class<?> thisclass, int arrayid, String choice)
        {
        return new AlertDialog.Builder(context)
        .setItems(arrayid, new OnClickListener()
            {
            @Override
            public void onClick(DialogInterface dialog, int which)
                {
                setChoice(thisclass, context, arrayid, which, choice);
                }
            })
        .create();
        }           
    public void setChoice(Class<?> thisclass, Context context, int arrayid, int which, String choice)
        {
        String[] array = context.getResources().getStringArray(arrayid);
        try
            {
            Field f = thisclass.getDeclaredField(choice);
            f.set(null, array[which]);
            }
        catch (SecurityException e)
            {
            e.printStackTrace();
            }
        catch (NoSuchFieldException e)
            {
            e.printStackTrace();
            }
        catch (IllegalArgumentException e)
            {
            e.printStackTrace();
            }
        catch (IllegalAccessException e)
            {
            e.printStackTrace();
            }
        }
    }

public class ClassA extends Activity
    {
    static String stringa;
    Setter setted = new Setter();
    ...
    public void onCreate()
        {
        super.onCreate();
        ...
        AlertDialog thinga = setted.myList(this, getclass(), R.array.thinga, stringa).show();
        ...
        }
    }

When I select an item from the list, I get this from debugger:

ClassCache.findFieldByName(Field[], String) line: 438   
Class.getDeclaredField(String) line: 666    
Setter.setChoice(Class, Context, int, int, String) line: 45 // the line with the Field

I think I’m passing it the class wrong but this is a bit out of my current depth.

I have a number of different classes each with their own static Strings. I am passing the method below the name of the String (in choice) and the context of what I had hoped was the original class that called a method that called a method that led to the code below. I was hoping I could call context.choice = something and the machine would read that as ClassA.stringa = something; how do I do that?

Briefly, I want to have a list of items that the user can choose from be the content of a dialogue, and have their selection be saved and accessible to the class that called for the creation of the dialogue. Perhaps I’m going about this all wrong but I got tired of dealing with other ‘kludges’ involving using spinners to do the same thing.

Because onClick can’t have non-final objects declared elsewhere (at least that is my understanding) I thought maybe I could get around that by calling to another method, setChoice that would store the value of whatever was chosen. I would definitively say this is a kludge and would love to be shown the light as to how you are supposed to deal with these things.

Answer 1

Java does not have closures, but you can get close with anonymous inner classes.

String output;
public void onCreate() {
    Setter.addActionListener(new ActionListener() {

        @Override
        public void actionPerformed(ActionEvent e) {
            output  = "selected";
        }
    });
}

See also this swing tutorial: http://download.oracle.com/javase/tutorial/uiswing/events/actionlistener.html

Edit:
In spirit of your example, this should look like this:

public class Setter
{
public void setChoice(IsetString setter, String something)
    {
    setter.setString(something);
    }
}


class ClassA extends Activity implements setString
{
static String stringa;
string polka = "dots";
Setter setted = new Setter();
...
public void onCreate()
    {
    super.onCreate();
    ...
    setted.setChoice(new IsetString() {

        @Override
        public void setString(String s) {
            stringa = s;
        }
    }, polka);
    ...
    }
}

interface IsetString {
    void setString(String s);
}