GridLayout struggle when it has excess rows and how to overcome

In my Java code, I am using GridLayout (line shown in red) in code below: frame = new JFrame("Contacts Details"); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); mainPanel = new JPanel(); buttonPanel = new JPanel(); mainPanel.setLayout(new GridLayout(9, 3)); buttonPanel.setLayout(new GridLayout(1, 3)); The result was this: Name [                        ] (Text Box for name) City [                        ] (Text Box for City) Cell [                        … Continue reading GridLayout struggle when it has excess rows and how to overcome

Where to place a text file for use with a Java project in Eclipse

I placed a text file myapp.txt in the folder ~/workspace/PayrollApp/src/org/username/payrollapp. However, it was not opening in the Java program. To make it work correctly, I had to do use the following path in the Java program when opening the file: src/org/username/payrollapp/pay.txt Code as follows: try { FileReader fr = new FileReader("src/org/username/payrollapp/pay.txt"); BufferedReader br = new … Continue reading Where to place a text file for use with a Java project in Eclipse

Where to place SQLite 3 database for use in a Java Project in Eclipse

My Eclipse Java project path is as follows: ~/workspace/PayrollApp/src/org/username/payrollapp/payroll.db I had placed the SQLite database file payroll.db in the above path, and found it was not getting used when I ran the Java program. Upon inspecting the contents of ~/workspace/PayrollApp, I found that payroll.db was there with 0 bytes. That implied that the file needs … Continue reading Where to place SQLite 3 database for use in a Java Project in Eclipse

Window Builder Pro hangs in Eclipse Luna on Ubuntu 14.04 LTS

If you use Eclipse IDE for Java development, you will find that there is a great GUI builder from Google, and it worked very well on previous releases of Ubuntu. Unfortunately, Eclipse just freezes when you use Windows Builder on 64 bit Ubuntu 14.04 LTS. Several posts on the Internet suggest installing Oracle Java 7 … Continue reading Window Builder Pro hangs in Eclipse Luna on Ubuntu 14.04 LTS

How to make a form refer to the parent frame using a JDialog

Below code segment shows how to use a JDialog to refer to a parent frame. MyApp.java public class MyApp { JDialog dialog; JFrame parentFrame; public static void main(String[] args) { MyApp app = new MyApp(); app.gui(); } public void gui() { //The parentFrame parentFrame = new JFrame(); parentFrame = setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //The dialog dialog = new … Continue reading How to make a form refer to the parent frame using a JDialog

Read data from a JTable created from AbstractTableModel

If you have a JTable in Java created with an AbstractTableModel, you can read the data from it, using following: int rowCount = testTable.getRowCount(); for (int i = 0; i < rowCount; i++) { String mColumn1 = (String) testTable.getModel().getValueAt(i, 0); String mColumn2 = (String) testTable.getModel().getValueAt(i, 1); } Alternatively, you could also try where the JTable … Continue reading Read data from a JTable created from AbstractTableModel

Java program bug due to multiple declaration of variable in code and the fix

I created a small Java class to accept a date. However, when I tried to use it, I got a NullPointerException error. This post is just to illustrate how it was fixed. 1 public class DateForm { 2 JFormattedTextField txtMyDate;     //This is a variable at class level 3 4 dateForm () { 5 JTextFormattedField … Continue reading Java program bug due to multiple declaration of variable in code and the fix

How to restrict size of JButton in GridLayout in Java

If you put the following code in Java with only the lines in blue in your Java Swing program, you will find that whenever the Java dialog is resized, the button grows and looks ugly as it occupies the full row of the GridLayout. Code Segment as below. parameterPanel.setLayout(new GridLayout(2,1)); JButton parameterButton = new JButton("Parameters"); … Continue reading How to restrict size of JButton in GridLayout in Java