jcomponent

I know the fact that when I create an instance of a JComponent, it has it's own preferred size. Now let's suppose that I setPreferredSize that JComponent manually with a dimension of 0 x 0. And i want that Component to "reset" its own preferredSize. How do I do that? Tormod 1) Setting preferred size to null should reset the component back to getting its preferred size calculated as if it was never set. component.setPreferredSize(null); This might not do what you want, depending on how you signal that the layout should be redone - but at least it is technically the answer to your question. 2)

What's the difference between Component.isShowing() and Component.isDisplayable() ? I want to use them to decide wheter I should stop/start a Timer. Pr0gr4mm3r A component isShowing() when Determines whether this component is showing on screen. This means that the component must be visible, and it must be in a container that is visible and showing. isShowing() is recursive and checks all parent components, too, but isDisplayable() and isVisible() verify only the state of the component, not that state of its parents. This means that your component is currently showing on the screen within a

The Problem is when I resize the JFrame the animation goes on with it's Pre supplied dimensions for JComponent . Is there a way that I can update my width and height variables as I resize the JFrame , so that the Animation can run along with the new Co-ordinates. In simpler terms, say the JComponent has initial width = 300 and height = 300 , so the BALL moves inside these specified Co-ordinates . Now if I resize my JFrame , the size for the JComponent still remains as is i.e. width = 300 and height = 300 , but what I was hoping for, is a way to modify these variables with the present size of

So basically I have some code I was working on a couple of days ago that is kind of like Paint, which allows you to essentially draw on the screen using the mouse. I kind of discovered this property by accident, and I realized that it is really inefficient and i'm wondering if there is a more practical way to do this. There isn't really any reason to give all of my code, but here are the important parts private static void createAndShowGui() { SimpleDraw mainPanel = new SimpleDraw(); MenuBar.createMenuBar(); JLabel label = new JLabel(); label.setText("Drawing prototype 0.0.1"); // label

I'm working on a map editor for my college project. And I had a problem that the map panel is not listening key event while it should. This happens when I add a ToolBarPane (which extends JPanel) with JComponent such as JButton, JComboBox that implements ActionListener on it AND the map panel (which extends the JPanel) together on to the Frame (I used BorderLayout). I have System.out.println statement to test if the key press is received, and it's not printing, if I remove the ToolBar, the key listener works again, so is the mouseListenner is disabled just like the keyListener, which means I