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This week I've been working on a mandatory task in Java Programming. It's quite simple, but I figured I'd make a challenge to it by adding a GUI. I have been working with Java GUI earlier on, but I barely remembered the horrors of how annoying the layout manager can be.

Let's start off with a simple example, and how it usually works.



This is quite simple, it contains a text input box, a button and a label, three quite easy things to stuff into the JPanel.

// ...
JPanel panel = new JPanel(); 
JLabel label = new JLabel(""); 
JTextField text = new JTextField(15);
JButton button = new JButton("Press me!"); 

panel.setLayout(new GridLayout(3, 1)); // A grid with 3 rows, 1 column.
panel.add(text); 
panel.add(button); 
panel.add(label); 
getContentPane().add(panel); 
validate(); // To refresh the frame making changes to it visible

Fair enough, right? Right. But when you are making more complex solutions, things get a much more nasty.

Now I do not say that I am an expert of Java and its GUI functions, but some of the aspects are quite annoying. Nested layouts are very messy. Let's take another example:

JButton button; 
JLabel nc, n, a, p; 
JTextField numbercode, name, amount, price; 
JPanel behind, panel; 

behind = new JPanel(); 
panel = new JPanel(); 

button = new JButton("Display receipt");
button.addActionListener(new Listener()); // I won't add the code for this class

nc = new JLabel("Number code: ");  
n = new JLabel("Name: "); 
a = new JLabel("Amount: ");
p = new JLabel("Price: "); 

numbercode = new JTextField(10); 
name = new JTextField(50);
amount = new JTextField(3); 
price = new JTextField(7); 

behind.setLayout(new GridLayout(2, 1));

panel.setLayout(new GridLayout(4, 2));
panel.setBorder(BorderFactory.createEmptyBorder(30,30,10,30)); // A cute border

// Let the fun begin
panel.add(nc);
panel.add(numbercode);
panel.add(n);
panel.add(name);
panel.add(a);
panel.add(amount);
panel.add(p);
panel.add(price);

behind.add(panel); 
behind.add(knapp); 
getContentPane().add(behind);
validate(); 

Now, I might not have used the best variables (I probably should have used label_ and button_ or such as prefixes for the different element types), but the thing is that it gets quite complexly in the end with even more nested layouts.

I know that there are different layout types, but I found grid to be the easiest. Though grid has some flaws, for instance: If my main window is 200 pixels in height and I have a GridLayout(2,1) for a JTextField and a JButton, I will get a JTextField of 100 pixels in height and a JButton with 100 pixels in height. I miss the possibility to set custom heights of different rows. There are other layout managers offering this, but I do not feel like I want to write 50 lines of code to be able to get this simple layout. A good example of the above scenario is this:



I will continue study this and hopefully figure out to use Swing's layout managers better. It seems I will be stuck with Java for quite some time.