CODEWITHSUNDEEP
javaarraysswingjcombobox
Dan
Dan

Reputation: 251

Java code for String arrays populating a ComboBox

years = new String[67];
for(int y = cal.get(Calendar.YEAR) - 13; y <= cal.get(Calendar.YEAR) - 80; y++) {
    for(int i = 0; i < years.length; i++){
        years[i] = Integer.toString(y);
    }
}
jComboBox1.setModel(new javax.swing.DefaultComboBoxModel(years));

I have this code for populating ComboBox with 67 dates however all I'm getting is empty values?

Upvotes: 0

Views: 4663

Answers (6)

aioobe
aioobe

Reputation: 420991

The body of the outer loop will never execute since the loop condition is false on the first iteration:

You try to go from x - 13 up to x - 80.

for(int y = cal.get(Calendar.YEAR) - 13; y <= cal.get(Calendar.YEAR) - 80; y++)
            ^^^^^^^^^^^^^^^^^^^^^^^^^^^       ^^^^^^^^^^^^^^^^^^^^^^^^^^^
               this is higher than...    ...this even in the first iteration

Also, to make sure -13 to -80 actually adds up to the length of the years array, I'd suggest you write it like this:

String[] years = new String[67];
int thisYear = cal.get(Calendar.YEAR);
int startYear = thisYear - 13;

for (int i = 0; i < years.length; i++)
    years[i] = Integer.toString(startYear - i);

jComboBox1.setModel(new javax.swing.DefaultComboBoxModel(years));

Upvotes: 4

Konstantin Tarashchanskiy
Konstantin Tarashchanskiy

Reputation: 2800

Several issues jump out at me: One, your loop executes exactly 0 times since cal.get(Calendar.YEAR) - 13 <= cal.get(Calendar.YEAR) - 80 so the loop will exit immediately.

Two, since you are going from a larger value (cal.get(Calendar.YEAR) - 13) to a smaller one (cal.get(Calendar.YEAR) - 80), you should not do y++ since it will increase y, you should instead use y--.

Finally, for(int i = 0; i < years.length; i++) will replace ALL of the values in years.

Upvotes: 0

JB Nizet
JB Nizet

Reputation: 691735

Supposing that the calendar is initialized with the current time, you go from year 1999 to year 1932. That makes an empty loop.

And what's the point in having those two nested loops?

Upvotes: 1

Guillaume Polet
Guillaume Polet

Reputation: 47608

Your for-loop end condition is true at the first iteration. Use this instead:

years = new String[67];

         for(int i = 0; i < years.length; i++){

            years[i] = Integer.toString(cal.get(Calendar.YEAR) - 13-i);
         }

jComboBox1.setModel(new javax.swing.DefaultComboBoxModel(years));

Upvotes: 0

redDevil
redDevil

Reputation: 1919

    for(int y = cal.get(Calendar.YEAR) - 13; y >= cal.get(Calendar.YEAR) - 80; **y--**) {

Upvotes: 0

Alex
Alex

Reputation: 11090

years = new String[67];
int index = 0;

    for(int y = cal.get(Calendar.YEAR) - 13; y >= cal.get(Calendar.YEAR) - 80; y--) {

            years[index++] = Integer.toString(y);
    }

jComboBox1.setModel(new javax.swing.DefaultComboBoxModel(years));

Upvotes: 0

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