MainClass.java Source code

Introduction

Here is the source code for MainClass.java

Source

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.VerifyEvent;
import org.eclipse.swt.events.VerifyListener;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Text;

public class MainClass {

    public static void main(String[] a) {
        Display display = new Display();

        // Create the main window
        Shell shell = new Shell(display);

        Text fahrenheit = new Text(shell, SWT.BORDER);
        fahrenheit.setData("Type a temperature in Fahrenheit");
        fahrenheit.setBounds(20, 20, 100, 20);

        fahrenheit.addVerifyListener(new VerifyListener() {
            public void verifyText(VerifyEvent event) {
                // Assume we don't allow it
                event.doit = false;

                // Get the character typed
                char myChar = event.character;
                String text = ((Text) event.widget).getText();

                // Allow '-' if first character
                if (myChar == '-' && text.length() == 0)
                    event.doit = true;

                // Allow 0-9
                if (Character.isDigit(myChar))
                    event.doit = true;

                // Allow backspace
                if (myChar == '\b')
                    event.doit = true;
            }

        });
        shell.open();

        while (!shell.isDisposed()) {
            if (!display.readAndDispatch()) {
                display.sleep();
            }
        }
        display.dispose();
    }
}