Hot questions for Using JTextField in gridbaglayout

Top Java Programmings / JTextField / gridbaglayout

Question:

I have searched all problems like this but I couldn't find the solution.

public class FormPanel extends JPanel
{
    private JLabel namelabel;
    private JLabel occlabel;
    private JTextField nametext;
    private JTextField occtext;
    private JButton okButton;

    public FormPanel() {
        Dimension dim = getPreferredSize();
        dim.width = 250;
        setPreferredSize(dim);
        namelabel = new JLabel("Name : ");
        occlabel = new JLabel("Occupation : ");
        nametext = new JTextField();
        nametext.setPreferredSize(new Dimension(80,20));
        occtext = new JTextField();
        occtext.setColumns(20);
        okButton = new JButton("OK");

        Border inner = BorderFactory.createTitledBorder("Add Person : ");
        Border outer = BorderFactory.createEmptyBorder(5,5,5,5);

        setBorder(BorderFactory.createCompoundBorder(inner,outer));
        setLayout(new GridBagLayout());
        GridBagConstraints gc = new GridBagConstraints();
        gc.gridx = 0;
        gc.gridy = 0;
        gc.weightx = 1;
        gc.weighty = 1;
        gc.fill = GridBagConstraints.NONE;

        add(namelabel,gc);
        gc.gridx = 1;
        gc.gridy = 0;
        add(nametext,gc);

        gc.gridy = 1;
        gc.gridx = 0;
        add(occlabel,gc);

        gc.gridy = 1;
        gc.gridx = 1;
        add(occtext,gc);

        gc.gridy = 2;
        gc.gridx = 1;
        add(okButton,gc);

    }
}

nametext and occtext are extremely small. I tried new JTextField(20) , and string version, I tried setPreferredSize as above class, and also I tried setColumn but none of them works.


Answer:

Get rid of setPreferredSize(dim);. Let the GUI size itself via calling pack() on the top-level Window and your problem will likely go away. You're constraining the size of the container likely to smaller than is best for it, and by doing so, the GridBagLayout will then shrink its components, including your JTextFields, in a bad way.

Question:

I am attempting to line up my JLabel that reads "Power Information" with the first column of Jlabels and have it so that the columns start from the left hand side of the window and end at the right hand side of the window.

Ive tried using anchors to the first column of Jlabels and then use anchors to move the text fields as well, but the while I can move the Jlabel columns the text field columns wont move an inch.

Can someone please help me figure this out?

edit: I am attempting to create

     public class PowerListener implements ActionListener 
     {
      public void actionPerformed(ActionEvent event)
     {
     JFrame frame = new JFrame("Power Creation");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setSize(550,400 );

        Toolkit tools = Toolkit.getDefaultToolkit();
        Dimension dim = tools.getScreenSize();

        int x = (dim.width / 2) - (frame.getWidth() / 2);
        int y = (dim.height / 2) - (frame.getHeight() / 2);

        frame.setLocation(x, y);

        //frame.setResizable(false);

         JTextField nameBox = new JTextField(6);
         JTextField levelBox = new JTextField(6);
         JTextField timingBox = new JTextField(6);

         JTextField skillBox = new JTextField(6);
         JTextField defenseBox = new JTextField(6);
         JTextField targetBox = new JTextField(6);

         JTextField RNGBox = new JTextField(6);
         JTextField encrochBox = new JTextField(6);
         JTextField restrictionBox = new JTextField(6);

         JTextField notesBox = new JTextField(4);

        JPanel panel1 = new JPanel(new GridBagLayout());

        GridBagConstraints c = new GridBagConstraints();

        c.insets = new Insets(5,5,5,5);

        //------------------------------------------------------------
        // Power Infromation
        //------------------------------------------------------------
        JLabel main = new JLabel("Power Information");
        main.setFont(new Font("Verdana", Font.BOLD, 12));
        c.gridx = 0;
        c.gridy = 0;
        //c.insets = new Insets(15,15,15,15)l;
        c.anchor = GridBagConstraints.CENTER;

        panel1.add(main,c);

        //c.insets = new Insets(5,5,5,5);

        c.anchor = GridBagConstraints.LINE_END;
        c.gridx = 0;
        c.gridy = 6;
        JLabel lname = new JLabel("Name:");
        panel1.add(lname,c);

        c.anchor = GridBagConstraints.BASELINE_LEADING;
        c.gridx = 1;
        c.gridy = 6;
        panel1.add(nameBox,c);

        c.anchor = GridBagConstraints.LINE_START;
        c.gridx = 2;
        c.gridy = 6;
        JLabel lLevel = new JLabel("Level:");
        panel1.add(lLevel,c);

        c.anchor = GridBagConstraints.CENTER;
        c.gridx = 3;
        c.gridy = 6;
        panel1.add(levelBox,c);

        c.anchor = GridBagConstraints.LINE_START;
        c.gridx = 4;
        c.gridy = 6;
        JLabel lTiming = new JLabel("Timing:");
        panel1.add(lTiming,c);

        c.anchor = GridBagConstraints.CENTER;
        c.gridx = 5;
        c.gridy = 6;
        panel1.add(timingBox,c);

        c.anchor = GridBagConstraints.LINE_END;
        c.gridx = 0;
        c.gridy = 7;
        JLabel lSkill = new JLabel("Skill:");
        panel1.add(lSkill,c);

        c.anchor = GridBagConstraints.CENTER;
        c.gridx = 1;
        c.gridy = 7;
        panel1.add(skillBox,c);

        c.anchor = GridBagConstraints.LINE_START;
        c.gridx = 2;
        c.gridy = 7;
        JLabel lDefense = new JLabel("Defense:");
        panel1.add(lDefense,c);

        c.anchor = GridBagConstraints.CENTER;
        c.gridx = 3;
        c.gridy = 7;
        panel1.add(defenseBox,c);

        c.anchor = GridBagConstraints.LINE_START;
        c.gridx = 4;
        c.gridy = 7;
        JLabel lTarget = new JLabel("Target:");
        panel1.add(lTarget,c);

        c.anchor = GridBagConstraints.CENTER;
        c.gridx = 5;
        c.gridy = 7;
        panel1.add(targetBox,c);

        c.anchor = GridBagConstraints.LINE_END;
        c.gridx = 0;
        c.gridy = 8;
        JLabel lRNG = new JLabel("RNG:");
        panel1.add(lRNG,c);

        c.anchor = GridBagConstraints.CENTER;
        c.gridx = 1;
        c.gridy = 8;
        panel1.add(RNGBox,c);

        c.anchor = GridBagConstraints.LINE_START;
        c.gridx = 2;
        c.gridy = 8;
        JLabel lencroach= new JLabel("Encroach:");
        panel1.add(lencroach,c);

        c.anchor = GridBagConstraints.CENTER;
        c.gridx = 3;
        c.gridy = 8;
        panel1.add(encrochBox,c);

        c.anchor = GridBagConstraints.LINE_START;
        c.gridx = 4;
        c.gridy = 8;
        JLabel lRestriction = new JLabel("Restriction:"+ " ");
        panel1.add(lRestriction,c);

        c.anchor = GridBagConstraints.CENTER;
        c.gridx = 5;
        c.gridy = 8;
        panel1.add(restrictionBox,c);

        frame.add(panel1);
        frame.setVisible(true);
 }

Answer:

  • Again, I'd display the GUI as a JDialog, not as a JFrame since it looks to be a dependent child window and not the main GUI application. If you display it as a modal dialog, you'll know exactly when the user is done using it, making extraction of information from it easy.
  • You look to be ignoring the weightx and weighty properties of your GridBagConstraints.
  • You're far better off calling pack() on your GUI after adding components, and not trying to set a component's or GUI's size.

For example:

import java.awt.BorderLayout;
import java.awt.Dialog.ModalityType;
import java.awt.event.ActionEvent;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.Window;
import java.util.HashMap;
import java.util.Map;

import javax.swing.*;

@SuppressWarnings("serial")
public class PowerDialogPanel extends JPanel {
    private static final int I_GAP = 4;
    public static final String[][] LABEL_TEXTS = {
        {"Name", "Level", "Timing"},
        {"Skill", "Defense", "Target"},
        {"RNG", "Encroach", "Restriction"}
    };
    private static final int TF_COLS = 10;
    private static final String TITLE_TEXT = "Power Information";
    private Map<String, JTextField> labelFieldMap = new HashMap<>();

    public PowerDialogPanel() {
        JPanel centerPanel = new JPanel(new GridBagLayout());
        for (int row = 0; row < LABEL_TEXTS.length; row++) {
            for (int col = 0; col < LABEL_TEXTS[row].length; col++) {
                String text = LABEL_TEXTS[row][col];
                JLabel label = new JLabel(text + ":");
                JTextField textField = new JTextField(TF_COLS);
                labelFieldMap.put(text, textField);

                int x = 2 * col;
                centerPanel.add(label, createGbc(x, row));
                centerPanel.add(textField, createGbc(x + 1, row));
            }
        }

        JButton submitButton = new JButton(new AbstractAction("Submit") {

            @Override
            public void actionPerformed(ActionEvent e) {
                Window win = SwingUtilities.getWindowAncestor(PowerDialogPanel.this);
                win.dispose();
            }
        });

        setLayout(new BorderLayout(I_GAP, I_GAP));
        add(new JLabel(TITLE_TEXT), BorderLayout.PAGE_START);
        add(centerPanel, BorderLayout.CENTER);
        add(submitButton, BorderLayout.PAGE_END);
    }

    public String getText(String labelText) {
        return labelFieldMap.get(labelText).getText();
    }

    private GridBagConstraints createGbc(int x, int y) {
        GridBagConstraints gbc = new GridBagConstraints();
        gbc.gridx = x;
        gbc.gridy = y;
        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.weightx = 1.0;
        gbc.weighty = 0.0;
        gbc.insets = new Insets(I_GAP, I_GAP, I_GAP, I_GAP);
        gbc.anchor = x % 2 == 0 ? GridBagConstraints.WEST : GridBagConstraints.EAST;
        return gbc;
    }

    private static void createAndShowGui() {
        final PowerDialogPanel powerDialogPanel = new PowerDialogPanel();

        final JFrame frame = new JFrame("Power Frame");
        final JDialog dialog = new JDialog(frame, "Power Dialog", ModalityType.APPLICATION_MODAL);
        dialog.add(powerDialogPanel);
        dialog.pack();
        dialog.setLocationRelativeTo(null);

        JPanel framePanel = new JPanel();
        framePanel.add(new JButton(new AbstractAction("Show Power Dialog") {

            @Override
            public void actionPerformed(ActionEvent arg0) {
                dialog.setVisible(true);
                for (String[] strings : LABEL_TEXTS) {
                    for (String labelText : strings) {
                        System.out.printf("%12s: %s%n", labelText, powerDialogPanel.getText(labelText));
                    }
                }
            }
        }));
        frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
        frame.getContentPane().add(framePanel);
        frame.pack();
        frame.setLocationByPlatform(true);
        frame.setVisible(true);
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGui();
            }
        });
    }
}

Question:

I am trying to create a JDialog that looks like this:

but where the JTextField spans two columns so that it almost reaches the "Find Next" button. However, when I try to set the gridwidth of the JTextField to 2, I get this:

Here is my code:

JDialog dialog = new JDialog(frame, "Find");
dialog.setPreferredSize(new Dimension(370, 129));
Point p = frame.getLocation();
dialog.setLocation(p.x + 53, p.y + 170);

Container c = dialog.getContentPane();
GridBagLayout gbl = new GridBagLayout();
c.setLayout(gbl);
GridBagConstraints gbc = new GridBagConstraints();

JLabel label = new JLabel("Find what:");
gbc.gridx = gbc.gridy = 0;
c.add(label, gbc);

JTextField field = new JTextField();
field.setMinimumSize(field.getPreferredSize());
gbc.gridx = 1;
gbc.fill = GridBagConstraints.HORIZONTAL;
gbc.gridwidth = 2;
c.add(field, gbc);

JButton findNext = new JButton("Find Next");
findNext.setPreferredSize(new Dimension(82, 23));
gbc.gridx = 3;
c.add(findNext, gbc);

JCheckBox check = new JCheckBox("Match case");
gbc.gridx = 0;
gbc.gridy = 1;
c.add(check, gbc);

JRadioButton up = new JRadioButton("Up"), down = new JRadioButton("Down");
ButtonGroup group = new ButtonGroup();
group.add(up);
group.add(down);
gbc.gridx = 1;
c.add(up, gbc);
gbc.gridx = 2;
c.add(down, gbc);

JButton cancel = new JButton("Cancel");
cancel.setPreferredSize(new Dimension(82, 23));
cancel.addActionListener(e2 -> dialog.dispose());
gbc.gridx = 3;
c.add(cancel, gbc);

Font f = new Font("Segoe UI", Font.PLAIN, 12);
c.setFont(f);
for (Component child : c.getComponents())
    child.setFont(f);

dialog.pack();
dialog.setDefaultCloseOperation(JDialog.DISPOSE_ON_CLOSE);
dialog.setResizable(false);
dialog.setVisible(true);

Thanks in advance!


Answer:

So two problems...

  1. You set the gridwidth to 2, but never reset it: gbc.gridwidth = 2;, this means that all subsequent uses of the GridBagConstraints has a gridwidth of 2
  2. Overuse of setPreferredSize, in fact, any use is overuse...

Solution...

Rest the gridwidth before re-using the GridBagConstraints...

gbc.gridwidth = 2;
c.add(field, gbc);

gbc.gridwidth = 1;
//...

Don't use setPreferredSize, you don't control the properties which can change the required size for components across multiple platforms.

See Should I avoid the use of set(Preferred|Maximum|Minimum)Size methods in Java Swing? for more discussions

With setPreferredSize:

Without setPrefferedSize:

Can you see the difference between the buttons?

If you want to add padding into a component use an EmptyBorder and/or GridBagConstraints#insets for starters

Question:

My form is very simple I just want to have labels next to text fields. The labels are default centering and it makes the form look weird. I want to the labels exactly next to the textfield. I have played with the horizontal alignment of the labels and textfields but it did not change anything.

Here is my code:

JPanel root = new JPanel(new GridBagLayout());
                 GridBagConstraints gbc = new GridBagConstraints();
                 gbc.insets= new Insets(0,0,0,0);

                 newVehicleRecord.setLayout(new BorderLayout());
                 newVehicleRecord.add(root,BorderLayout.PAGE_START);


                 JLabel title = new JLabel("New Vehicle Record - Customer ID:" + customerIDInfo.getText());
                 title.setFont(fontTitle);
                 gbc.weightx = 0;
                 gbc.gridx = 0; gbc.gridy = 0; gbc.gridwidth= 2;

                 root.add(title,gbc);

                 gbc.gridx = 0; gbc.gridy = 0; gbc.gridwidth= 1;
                 root.add(Box.createVerticalStrut(15),gbc);


                 gbc.gridx = 0; gbc.gridy = 2;
                 JLabel classificationLabel = new JLabel("Classification:");
                 classificationLabel.setHorizontalAlignment(JLabel.RIGHT);
                 root.add(classificationLabel,gbc);

                 gbc.gridx = 1; gbc.gridy = 2;
                 JTextField classificationTextField = new JTextField(10);
                 classificationTextField.setHorizontalAlignment(JTextField.LEFT);
                 root.add(classificationTextField,gbc);

                 gbc.gridx = 0; gbc.gridy = 3;
                  JLabel modelLabel = new JLabel("Model:");
                 root.add(modelLabel,gbc);

                 gbc.gridx = 1; gbc.gridy = 3;
                 JTextField modelTextField = new JTextField(10);
                 root.add(modelTextField,gbc);

                 gbc.gridx = 0; gbc.gridy = 4;
                  JLabel makeLabel = new JLabel("Make:");
                 root.add(makeLabel,gbc);

                 gbc.gridx = 1; gbc.gridy = 4;
                 JTextField makeTextField = new JTextField(10);
                 root.add(makeTextField,gbc);

I get the following display: http://prntscr.com/6j3iki

As you can see there is a lot of empty space between the label and the textfield which I don't want.


Answer:

I want to the labels exactly next to the textfield.

You need to play with the anchor constraint:

gbc.anchor = GridBagConstraints.LINE_END;
panel.add(label, gbc);
gbc.anchor = GridBagConstraints.LINE_START;
panel.add(textField, gbc);

Also you would probably want something like:

gbc.insets = new Insets(5, 10, 5, 10);

so the right edge of the label has some space between the left edge of the text field.

Read the section from the Swing tutorial on How to Use GridBagLayout for more information on all the constraints.

Question:

Some background: I am making a program that uses a JTree full of nodes of various types. The TreeSelectionListener determines what type of node it is, clears an inner JPanel of components, then adds the appropriate JPanel to the JPanel it just cleared, to edit properties specific to that type of node. The JPanel uses GridBagLayout, but the text fields aren't displaying correctly (Note: the title is a JTextField, the description is a JTextArea:

Code for the JPanel is as follows:

class nodePanel extends JPanel{
        public nodePanel(DefaultMutableTreeNode info){
            super(new GridBagLayout());

            GridBagConstraints c = new GridBagConstraints();
            c.insets=new Insets(10,10,10,10);
            c.gridx=0;
            c.gridy=0;
            c.gridheight=1;
            c.gridwidth=1;
            c.weightx=0;
            c.weighty=0;

            c.fill=GridBagConstraints.NONE;
            c.anchor=GridBagConstraints.EAST;
            this.add(new JLabel("Title: "),c);

            c.gridy=1;
            c.weighty=2;
            c.gridheight=2;
            this.add(new JLabel("Description: "),c);

            c.gridx=1;
            c.gridy=0;
            c.gridheight=1;
            c.gridwidth=2;
            c.weightx=100;
            c.weighty=0;
            c.anchor=GridBagConstraints.WEST;
            c.fill=GridBagConstraints.HORIZONTAL;
            JTextField title = new JTextField();
            title.setMinimumSize(new Dimension(300,25));
            this.add(title,c);

            c.gridy=1;
            c.gridheight=2;
            c.weighty=200;
            JTextArea description = new JTextArea();
            JScrollPane descriptionScroll= new JScrollPane(description);
            descriptionScroll.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
            descriptionScroll.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_NEVER);
            this.add(descriptionScroll, c);
        }
}

Thank you


Answer:

// ..
JTextField title = new JTextField(20);  // suggest a size in columns!
//title.setMinimumSize(new Dimension(300,25)); // don't call these methods! (1)
this.add(title,c);

c.gridy=1;
c.gridheight=2;
c.weighty=200;
JTextArea description = new JTextArea(3, 15); // suggest a size in rows/cols!
// ..    
  1. See Should I avoid the use of set(Preferred|Maximum|Minimum)Size methods in Java Swing? (Yes.)

Question:

So have a JFrame which contains 2 JPanels and one Button using the GridBagLayout. But the problem lies with the Panels which also use GridBagLayouts. JPanel p_addIng has has a 3x2 Grid with two JTextFields in the first column one the the size of the first is fine but the second one is way too thin.

Some disclaimers ahead: ing stands for ingredient, gbc for GridBagConstraints, everything with b_var means its a swing component b = JButton, tf = JTextField, p = JPanel, cb = JCombobox.

What i've already tried because of other posts: gbc_addIng.fill = GridBagConstraints.HORIZONTAL; gbc_addIng.weightx = 1; i saw also somewhere to use the pack() method but this was for the JFrame and didn't do anything to fix the problem. Here's the code:

//making a new panel
//initializing the new Panel
p_addIng = new JPanel();
p_addIng.setName("Adding an Ingredient");
p_addIng.setPreferredSize(ingPanelDim);
p_addIng.setLayout(new GridBagLayout());
GridBagConstraints gbc_ing = new GridBagConstraints(0, 0, 1, 1, 1, 0,
                                                    GridBagConstraints.CENTER, GridBagConstraints.BOTH
                                                    new Insets(0,0,0,0),10, 10);

//the components of the panel
//TextField to set the name of the Ingredient
gbc_ing.gridx = 0; //the position of the component on the panel
gbc_ing.gridy = 0;
tf_ingName = new JTextField();
tf_ingName.setPreferredSize(new Dimension(ingPanelDim.width / 2, ingPanelDim.height/2));
tf_ingName.addActionListener(this);
p_addIng.add(tf_ingName, gbc_ing); //adding the component to the Panel
//endOfTextFieldIngName
gbc_ing.gridx = 1;
gbc_ing.gridy = 0;
//button to add the ingredient
tf_amnt = new JTextField("Choose amount");
tf_amnt.setPreferredSize(new Dimension(ingPanelDim.width/4, ingPanelDim.height/2));
tf_amnt.addActionListener(this);
p_addIng.add(tf_amnt, gbc_ing);
//endOfButtonToAddIng
//button to add the ingredient
gbc_ing.gridx = 2;
gbc_ing.gridy = 0;
UnitOfMeasurement[] un = {UnitOfMeasurement.g, UnitOfMeasurement.kg, UnitOfMeasurement.Stück, UnitOfMeasurement.L, UnitOfMeasurement.ml, UnitOfMeasurement.cm};
cb_measurement = new JComboBox<UnitOfMeasurement>(un);
cb_measurement.setPreferredSize(new Dimension(ingPanelDim.width/4, ingPanelDim.height/2));
cb_measurement.addActionListener(this);
p_addIng.add(cb_measurement, gbc_ing);
//endOfButtonToAddIng
//button to add the ingredient
gbc_ing.gridx = 0;
gbc_ing.gridy = 1;
b_addIng = new JButton("Add Ingredient");
b_addIng.setPreferredSize(new Dimension(ingPanelDim.width/2, ingPanelDim.height/2));
b_addIng.addActionListener(this);
p_addIng.add(b_addIng, gbc_ing);
//endOfButtonToAddIng
//button to remove the ingredient
gbc_ing.gridx = 2;
gbc_ing.gridy = 1;
b_removeIng = new JButton("Remove Ingredient");
b_removeIng.setPreferredSize(new Dimension(ingPanelDim.width/2, ingPanelDim.height/2));
b_removeIng.addActionListener(this);
p_addIng.add(b_removeIng, gbc_ing);
//endOfButtonToRemoveIng
//
frame.pack();
frame.add(p_addIng,gbc_frame);
//

Here ,as wished, is the fully functional class the only thing thats missing is the enumeration UnitOfMeasurement which contains the elements as shown in the list for cb_meausrement:

package WindowDesign;

import Food.UnitOfMeasurement;

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.LinkedList;

public class StartingWindow implements ActionListener {

    //window dimension
    private static final int WIDTH = 500;
    private static final int HEIGHT = 200;
    //

    //the JFrame
    private JFrame frame;
    //JComponents
    //adding an Ingredient
    private JPanel p_addIng;
    private Dimension ingPanelDim = new Dimension(WIDTH/2, HEIGHT/2);
    private JButton b_addIng; //a button to add an Ingredient
    private JButton b_removeIng;
    private JTextField tf_ingName;
    private JTextField tf_amnt;
    private JComboBox<UnitOfMeasurement> cb_measurement;
    //

    //adding a Recipe
    private JPanel p_addRecipe;
    private JButton b_addRecipe;    // add a Recipe to the list of Recipes
    private JButton b_removeRecipe;
    private JButton b_buildRecipe;
    private JButton b_clearRecipe;
    private JTextField tf_recipeName;
    private JTextField tf_ingredient;
    private JComboBox<UnitOfMeasurement> cb_measurementR;
    //

    //

    private JButton b_findCombination; //find the right combination of things to buy
    private JButton b_exit; //exit the program

    public StartingWindow(String name) {
        frame = new JFrame(name);
        frame.setLayout(new GridBagLayout());
        //constraints
        GridBagConstraints gbc_frame = new GridBagConstraints();
        frame.setSize(WIDTH, HEIGHT);
        frame.setBackground(Color.LIGHT_GRAY);
        gbc_frame.ipadx = 10;
        gbc_frame.ipady = 10;
        gbc_frame.weightx = 1;
        gbc_frame.fill = GridBagConstraints.BOTH;
        //Adding the Panels
        gbc_frame.gridx = 0;
        gbc_frame.gridy = 0;
        implementIngredientPanel(gbc_frame);

        gbc_frame.gridx += 1;
        gbc_frame.gridy = 0;
        implementRecipePanel(gbc_frame);
        //

        gbc_frame.gridx = 0;
        gbc_frame.gridy = 1;
        implementStartingPanel(gbc_frame);

        /*



        b_exit = new JButton("exit");
        b_exit.addActionListener(this);

         */

        /*
        frame.add(b_findCombination);
        frame.add(b_addIng);
        frame.add(b_addRecipe);
        frame.add(b_exit);
         */

        frame.setResizable(false);
        frame.setDefaultCloseOperation(frame.EXIT_ON_CLOSE);
        frame.requestFocus();
        frame.setLocationRelativeTo(null);
        frame.pack();
        frame.setVisible(true);

    }
    //helper function to organize code
    private void implementIngredientPanel(GridBagConstraints gbc_frame){
        //making a new panel
        //initializing the new Panel
        p_addIng = new JPanel();
        p_addIng.setName("Adding an Ingredient");
        p_addIng.setPreferredSize(ingPanelDim);
        p_addIng.setLayout(new GridBagLayout());
        GridBagConstraints gbc_ing = new GridBagConstraints(0, 0, 1, 1, 1, 0,
                                                            GridBagConstraints.CENTER, GridBagConstraints.BOTH,
                                                            new Insets(0,0,0,0),10, 10);

        //the components of the panel
        //TextField to set the name of the Ingredient
        gbc_ing.gridx = 0; //the position of the component on the panel
        gbc_ing.gridy = 0;
        tf_ingName = new JTextField();
        tf_ingName.setPreferredSize(new Dimension(ingPanelDim.width / 2, ingPanelDim.height/2));
        tf_ingName.addActionListener(this);
        p_addIng.add(tf_ingName, gbc_ing); //adding the component to the Panel
        //endOfTextFieldIngName
        gbc_ing.gridx = 1;
        gbc_ing.gridy = 0;
        //button to add the ingredient
        tf_amnt = new JTextField("Choose amount");
        tf_amnt.setPreferredSize(new Dimension(ingPanelDim.width/4, ingPanelDim.height/2));
        tf_amnt.addActionListener(this);
        p_addIng.add(tf_amnt, gbc_ing);
        //endOfButtonToAddIng
        //button to add the ingredient
        gbc_ing.gridx = 2;
        gbc_ing.gridy = 0;
        UnitOfMeasurement[] un = {UnitOfMeasurement.g, UnitOfMeasurement.kg, UnitOfMeasurement.Stück, UnitOfMeasurement.L, UnitOfMeasurement.ml, UnitOfMeasurement.cm};
        cb_measurement = new JComboBox<UnitOfMeasurement>(un);
        cb_measurement.setPreferredSize(new Dimension(ingPanelDim.width/4, ingPanelDim.height/2));
        cb_measurement.addActionListener(this);
        p_addIng.add(cb_measurement, gbc_ing);
        //endOfButtonToAddIng
        //button to add the ingredient
        gbc_ing.gridx = 0;
        gbc_ing.gridy = 1;
        b_addIng = new JButton("Add Ingredient");
        b_addIng.setPreferredSize(new Dimension(ingPanelDim.width/2, ingPanelDim.height/2));
        b_addIng.addActionListener(this);
        p_addIng.add(b_addIng, gbc_ing);
        //endOfButtonToAddIng
        //button to remove the ingredient
        gbc_ing.gridx = 2;
        gbc_ing.gridy = 1;
        b_removeIng = new JButton("Remove Ingredient");
        b_removeIng.setPreferredSize(new Dimension(ingPanelDim.width/2, ingPanelDim.height/2));
        b_removeIng.addActionListener(this);
        p_addIng.add(b_removeIng, gbc_ing);
        //endOfButtonToRemoveIng
        //
        frame.pack();
        frame.add(p_addIng,gbc_frame);
        //
    }

    private void implementRecipePanel(GridBagConstraints gbc_frame){
        //Adding a Panel to add
        p_addRecipe = new JPanel();
        p_addRecipe.setName("Adding an Ingredient");
        p_addRecipe.setPreferredSize(new Dimension(WIDTH/2, HEIGHT/2));
        p_addRecipe.setLayout(new GridBagLayout());
        GridBagConstraints gbc_recipe = new GridBagConstraints();


        //the components:
        //add Button to Add a Recipe
        b_addRecipe = new JButton("Add Recipe");
        b_addRecipe.addActionListener(this);
        p_addRecipe.add(b_addRecipe, gbc_recipe );
        //

        frame.add(p_addRecipe, gbc_frame);
    }

    private void implementStartingPanel(GridBagConstraints c){
        b_findCombination = new JButton("go shopping!");
        b_findCombination.addActionListener(this);
        c.fill = GridBagConstraints.HORIZONTAL;

        frame.add(b_findCombination, c);
    }

    @Override
    public void actionPerformed(ActionEvent actionEvent) {

    }
}


Answer:

Here is a working example that may or may not be what you're asking for...

package stackoverflow;

import javax.swing.*;
import java.awt.*;

public class IngredientJFrame {

    public static void main(String... args) {

        IngredientJFrame ingredientJFrame = new IngredientJFrame();
        ingredientJFrame.init();
    }

    public void init() {

        JFrame jFrame = new JFrame();

        //making a new panel
        //initializing the new Panel
        JPanel p_addIng = new JPanel();
        p_addIng.setLayout(new GridBagLayout());

        GridBagConstraints gbc_ing = new GridBagConstraints();

        JLabel l_addIng = new JLabel("Add Ingredient");
        gbc_ing.gridx = 0;
        gbc_ing.gridy = 0;
        p_addIng.add(l_addIng, gbc_ing);

        JTextField tf_ingName = new JTextField();
        gbc_ing.gridx = 1;
        gbc_ing.gridy = 0;
        gbc_ing.fill = GridBagConstraints.HORIZONTAL;
        p_addIng.add(tf_ingName, gbc_ing); //adding the component to the Panel

        JLabel tf_amnt = new JLabel("Choose amount");
        gbc_ing.gridx = 0;
        gbc_ing.gridy = 1;
        gbc_ing.fill = GridBagConstraints.NONE;
        p_addIng.add(tf_amnt, gbc_ing);

        JComboBox cb_measurement = new JComboBox();
        gbc_ing.gridx = 1;
        gbc_ing.gridy = 1;
        gbc_ing.fill = GridBagConstraints.HORIZONTAL;
        p_addIng.add(cb_measurement, gbc_ing);

        JButton b_addIng = new JButton("Add Ingredient");
        gbc_ing.gridx = 0;
        gbc_ing.gridy = 2;
        gbc_ing.fill = GridBagConstraints.NONE;
        p_addIng.add(b_addIng, gbc_ing);

        JButton b_removeIng = new JButton("Remove Ingredient");
        gbc_ing.gridx = 1;
        gbc_ing.gridy = 2;
        p_addIng.add(b_removeIng, gbc_ing);

        jFrame.pack();
        jFrame.add(p_addIng);
        jFrame.setSize(500, 500);
        jFrame.setVisible(true);
    }
}

GridBayLayout (GBL) and GridBagConstraints (GBC) are powerful, but hard to use properly, and easy to screw up.

Here are some pointers on how I use to use these two classes and other tips for making a Swing based UI:

  • Text, in general, should be displayed using a JLabel. That should help right away with your formatting.
  • In general with GBL and GBC we don't normally set actual sizes on our components. We allow the components to react to one another and fill the space as needed. Often times using JPanels inside of other JPanels to get the correct flow that we are looking for.
  • The way that I use GBC is most likely not great, but I hate having to remake that object over and over and over and over again. So, I reused it in my example, you just have to be careful when reusing that object because it is easy to set one particular field and forget to 'unset' it later. Thing insets.
  • Typically a component has an anonymous inner class that actually does the listening to the component.

Question:

The layout of the JFrame in the picture is a GridBagLayout. The e-mail JTextfield has a gridwidth of 3. Is there any possibility to give this JTextfield a 100% width to fill the whole grid cell?

The fields are added dynamically. So give it a static width value width setColumns is not an option.


Answer:

GridBagConstraints c = new GridBagConstraints();
button = new JButton("Button");
c.fill = GridBagConstraints.HORIZONTAL;
yourPanel.add(button, c);

Question:

With the Java GridBagLayout why is there a large space to the right of the first JTextField (Labeled A) before the column but the last two JTextField's B and C behave as expected without unwanted spaces between them and how can I eliminate the space? I've attached an image below to show the problem along with the code.

    /* Label digital timer */
    gbcRightPanel.gridx = 0;
    gbcRightPanel.gridy = 0;
    rightPanel.add(labelDitigalTimer, gbcRightPanel);

    /* Text Field Hours */
    gbcRightPanel.gridx = 0;
    gbcRightPanel.gridy = 1;
    gbcRightPanel.weighty = 1;
    rightPanel.add(jtxtFieldHours, gbcRightPanel);

    /* Label colon */
    gbcRightPanel.gridx = 1;
    gbcRightPanel.gridy = 1;
    rightPanel.add(new JLabel(":"), gbcRightPanel);

    /* Text Field Minuites */
    gbcRightPanel.gridx = 2;
    gbcRightPanel.gridy = 1;
    rightPanel.add(jtxtFieldMinuites, gbcRightPanel);

    /*Colon*/
    gbcRightPanel.gridx = 3;
    gbcRightPanel.gridy = 1;
    rightPanel.add(new JLabel(":"), gbcRightPanel);

    /* Text Field Seconds */
    gbcRightPanel.gridx = 4;
    gbcRightPanel.gridy = 1;
    rightPanel.add(jtxtFieldSeconds, gbcRightPanel);    


Answer:

A GridBagLayout works with cells consisting of row/columns.

The first row has a single column. The second row has 5 columns.

So the width of column 1 is the width of the largest component in all the rows of the first column which happens to be your label so you see the extra space.

One way to change this is to have the label take up 5 columns. So before you add the label you need to use:

gbcRightPane.gridWidth = 5;
rightPanel.add(labelDitigalTimer, gbcRightPanel);
gbcRightPane.gridWidth = 1; // reset for the other components.

Now the label will appear above all 5 of the components. You can then determine whether you want the label centered or left justified by specifying an appropriate constraint.

Read the section from the Swing tutorial on How to Use GridBagLayout for more information about the constraints and working examples.

Another approach is to use nested panels. So you can create a separate panel for the text fields and colon labels. Then in the GridBagPanel you add the label and the panel as two separate components.

Read up on the other layout managers from the tutorial to get an idea how each layout manager works to you can effectively nest panels to get the desired layout.

Question:

I have an array of JSliders and JTextfields and I want to place a JTextfield then a JSlider below, move left and place the next JTextfield, Jslider again.

        setLayout(new GridBagLayout());

        JTextField[] textField = new JTextField[NUM_CHANNELS + 1];

        JSlider[] sliders = makeSliders(NUM_CHANNELS + 1);

        for (int i = 0; i < NUM_CHANNELS + 1; i++) {

            textField[i] = new JTextField();

            textField[i].setText("Channel " + (i + 1));

            add(textField[i]);

            add(sliders[i]);
        }

With the above, I get JTextField - JSlider ... in a row.


Answer:

You need to add GridBagConstraints when you add your components

   GridBagConstraints gbc = new GridBagConstraints();
   for (int i = 0; i < NUM_CHANNELS + 1; i++) {
        gbc.gridy = 0;
        textField[i] = new JTextField();

        textField[i].setBorder(BorderFactory.createEmptyBorder(0, 0, 0, 0));

        textField[i].setText("Channel " + (i + 1));

        add(textField[i], gbc);
        gbc.gridy = 1;
        add(sliders[i], gbc);
        gbc.gridx++;
    }