Question

I need to display an image in a JFrame. How can I make the window size to be automatically adjusted based on the size of the image.

Answer 1

1.in the case that you put image as Icon / ImageIcon to the JLabel then

• have to test for MaximumSize for JFrame that returned Toolkit for concrete monitor

• if PreferedSize is lower than MaximumSize size then call JFrame#pack()

• otherwise have to call setSize()

2.in the case that you put image as Icon / ImageIcon by using Custom Painting to the JComponent, JPanel, JLabel e.i. then

• then this JComponent must to returns PreferredSize

  a) call JFrame#pack() if PreferedSize is lower than MaximumSize,

  b) otherwise have to call JFrame#setSize()

  c) by assume that you don’t use Image#getScalledInstance

3.I’d be to use Icon in the JLabel, there is only one issue that image can be smaller then expected size on the screen, but no issue with that, is pretty possible to centering image to the JLabel.CENTER to the JLabel