I’m experimenting with writing some Swift code to target the JVM with Swing APIs. I’m working with Fire on macOS. Bit of background: I’m an experienced Java developer (written large Swing-based apps) and iOS/macOS developer (Swift; I have reasonably successful apps on the app store).
Now, I’m trying to get the simplest of simple Swing apps up and running - a JFrame with a JLabel. First of all, the project template I’ve had the most success with is the console application, and then modifying from there. This is what I’ve come up with:
import javax.swing
import java.awt
System.out.println("The magic happens here.")
EventQueue.invokeAndWait {
System.out.println("Hello from the event queue")
let frame = JFrame("This is the frame title")
let label = JLabel("This is a label")
frame.getContentPane().setLayout(FlowLayout())
frame.getContentPane().add(label)
frame.pack()
frame.setVisible(true)
}
System.`in`.read()
If I run this from within Fire, it fails to load any of the Swing-related UI classes or resources, although it does spit out the message “Hello from the event queue”. I have cooper, rt and swift as References in the project. The last line (System.in.read()) seems necessary because even though the event thread is running, when execution reaches the end of the file, the program terminates (unlike the Java language equivalent, compiled with javac).
If I run the compiled jar output from the above program, then it runs fine - I get the frame with label, as expected, with no runtime errors. However, this is quite tedious - write code in Fire, build, then switch to terminal in order to run/view the results. What am I missing in terms of configuring the project so that I can just run it from the IDE?
For reference, here is the roughly equivalent Java code:
import java.util.*;
import javax.swing.*;
import java.awt.*;
public class Main implements Runnable {
public static void main(String[] args) throws Exception {
System.out.println("The magic happens here.");
EventQueue.invokeAndWait(new Main());
}
public void run() {
System.out.println("Hello from the event queue");
JFrame frame = new JFrame("This is the frame title");
JLabel label = new JLabel("This is a label");
frame.getContentPane().setLayout(new FlowLayout());
frame.getContentPane().add(label);
frame.pack();
frame.setVisible(true);
}
}
One more thing - am I missing something in the IDE? Code completion lets me complete function/class names, but it provides no hints whatsoever about function parameters that I can see, unless you first type the () after the method call, then cursor back into the brackets, then press command-P, which is quite tedious. Then it only tells you the types of the arguments in the java library, and not the parameter names.
Finally, the editor could use a few “standard” keyboard shortcuts for text editing that work in all standard Apple text components e.g. OPTION+DEL should delete the previous word. CMD+DEL should delete to beginning of line, etc.
Apologies for the length of time I’ve been away - had computer issues (my iMac died) and this is also currently a side-project to evaluate viability for using this in future projects.