Question

Runnable r = new Runnable() {
    @Override
    public void run() {
        if(varx) {
            new displayFullScreen().setVisible(true);
        } else {
            javax.swing.JOptionPane.showMessageDialog(this, "dfv"); // this statement gives an error
        }
    }
};
new Thread(r,"full_screen_display").start();

The error in the marked line says "No suitable method found for anonymous (<java.lang.Runnable>,java.lang.String)“

Why does it so when i have directly written javax.swing._CLASS_ ?

Answer 1

The problem is that this in that line refers to the anonymous Runnable instance you’ve created, not the class that surrounds it. You’ll need to be more explicit about what this you mean in there.

If the enclosing class is named Foo, and is a swing Component, you should write:

javax.swing.JOptionPane.showMessageDialog(Foo.this, "dfv"); 

See the Nested Classes docs for more information.