please someone tell me how to change the size of the button.the code:

JButton button1 = new JButton();
    JButton button1 = new JButton();

    public Mainmenu() {
        setLayout(new FlowLayout(100,278,158));

        Icon button2= new ImageIcon(getClass().getResource("button1.jpg"));
        button2=new JButton(button2);
        add(button);

        Icon button2= new ImageIcon(getClass().getResource("button2.jpg"));
        button2=new JButton(button2);
        add(button2);

        HandlerC hand = new HandlerC();
        button1.addActionListener(hand);
        button2.addActionListener(hand);

    }       
    private class HandlerC implements ActionListener {
        public void actionPerformed(ActionEvent e) {            

        }
    }
    }

What size do you want it to be? Eg If you have multiple buttons do you want them all to be the same size?
setPrefferedSize is a last resort really ,because you set the size in pixels the when someone runs yur code on a retina display it looks really silly...

You can set the size of your button like this:

this.setlayoutManager(null); //Where the button is placed on a panel / frame / ...
Button but = new Button("Button");
but.setBounds(x,y,w,l); //xposition / uposition / width /length
this.add(but);

Using a null layout manager is a really bad idea unless you are coding for some very specific hardware configuration and the code will never run run on (eg) a Mac retina display. Pixel sizes are very different from one machine ot the next, so they are a near-usless way of specifying layout that has any text anywhere in it.

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