Combobox null pointer exception

[lrdblk]

So I made a Combobox and added stuff to it like so...

cmbBank = new JComboBox<>();

        cmbBank.setModel(new DefaultComboBoxModel<>(new String[] {
            "YES",
            "NO"
        }));

I want to convert the choice to a boolean.  Start button code..

private void button1ActionPerformed(ActionEvent e) {
        script.setShouldBank(getSelection(cmbBank.getSelectedItem()));
        script.setShouldStart(true); //start script
        this.setVisible(false);
    }

    private boolean getSelection(Object o){
        if(o.toString().equalsIgnoreCase("yes")){
            return true;
        }
        return false;
    }

Error that I'm getting

ERROR][01/18 03:29:45 PM]: Uncaught exception!
java.lang.NullPointerException
	at GuiMain.cmbBankActionPerformed(GuiMain.java:36)
	at GuiMain.lambda$initComponents$0(GuiMain.java:65)
	at javax.swing.JComboBox.fireActionEvent(Unknown Source)
	at javax.swing.JComboBox.setSelectedItem(Unknown Source)
	at javax.swing.JComboBox.setSelectedIndex(Unknown Source)
	at javax.swing.plaf.basic.BasicComboPopup$Handler.mouseReleased(Unknown Source)
	at java.awt.AWTEventMulticaster.mouseReleased(Unknown Source)
	at java.awt.Component.processMouseEvent(Unknown Source)
	at javax.swing.JComponent.processMouseEvent(Unknown Source)
	at javax.swing.plaf.basic.BasicComboPopup$1.processMouseEvent(Unknown Source)
	at java.awt.Component.processEvent(Unknown Source)
	at java.awt.Container.processEvent(Unknown Source)
	at java.awt.Component.dispatchEventImpl(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
	at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
	at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Window.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
	at java.awt.EventQueue.access$500(Unknown Source)
	at java.awt.EventQueue$3.run(Unknown Source)
	at java.awt.EventQueue$3.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
	at java.awt.EventQueue$4.run(Unknown Source)
	at java.awt.EventQueue$4.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
	at java.awt.EventQueue.dispatchEvent(Unknown Source)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.run(Unknown Source)

What am I doing wrong?  Or is there a better way to do this

[Chris]

just use a checkbox bro

[lrdblk]

just use a checkbox bro

 

LMAO i may actually do that.  Let's assume I want to learn something  .  Gonna have to use combobox eventually

[Hayase]

Since you are using a combobox and your options are stored in an array of strings why not just handle them based on the index of the string?

 

We know that at index 0 in your box, answer is "Yes"  

setShouldBank = cmbBank.getSelectedIndex() == 0;

If the selected index is 0, setShouldBank will be true.

If you absolutely need the name of the value use this:

String selectedIndex = cmbBank.getItemAt(cmbBank.getSelectedIndex());

[Explv]

So I made a Combobox and added stuff to it like so...

cmbBank = new JComboBox<>();

        cmbBank.setModel(new DefaultComboBoxModel<>(new String[] {
            "YES",
            "NO"
        }));

I want to convert the choice to a boolean.  Start button code..

private void button1ActionPerformed(ActionEvent e) {
        script.setShouldBank(getSelection(cmbBank.getSelectedItem()));
        script.setShouldStart(true); //start script
        this.setVisible(false);
    }

    private boolean getSelection(Object o){
        if(o.toString().equalsIgnoreCase("yes")){
            return true;
        }
        return false;
    }

What am I doing wrong?  Or is there a better way to do this

 

 

In this case a JCheckBox would make more sense, however, if you want to use a JComboBox, this works:

JComboBox<String> optionSelector = new JComboBox<>(new String[]{ "Yes", "No" });

To check if "Yes" is selected:

boolean yesSelected = optionSelector.getSelectedItem().toString().equals("Yes");

Edited January 18, 2017 by Explv

[lrdblk]

Since you are using a combobox and your options are stored in an array of strings why not just handle them based on the index of the string?

 

We know that at index 0 in your box, answer is "Yes"  

 

setShouldBank = cmbBank.getSelectedIndex() == 0;

If the selected index is 0, setShouldBank will be true.

If you absolutely need the name of the value use this:

String selectedIndex = cmbBank.getItemAt(cmbBank.getSelectedIndex());

 

 

 

In this case a JCheckBox would make more sense, however, if you want to use a JComboBox, this works:

JComboBox<String> optionSelector = new JComboBox<>(new String[]{ "Yes", "No" });

To check if "Yes" is selected:

boolean yesSelected = optionSelector.getSelectedItem().toString().equals("Yes");

 

got it working, the issue was completly unrelated.  fucked up my GUI constructor which was causing issues.

 

for the record, both your solutions worked for me though.  thanks for your help