I have an image that is too tall for my JFrame even when it is maximized. I want to dynamically resize it so that the image will never be clipped by the top or bottom of the JFrame. I have inserted the image within a JLabel as an ImageIcon. I have tried setting the maximum size to no avail. How do I ensure that the height of the image will never be larger than the JFrame? I would ideally like to keep the ratio of height to width constant. The image is in a portrait orientation. Any ideas?
public class myClass extends JFrame {
private void initGUI(){
pane = getContentPane();
pane.setLayout(new BorderLayout());
next = new JButton("Next");
previous = new JButton("Previous");
page = new JLabel(loadImg());
page.setMaximumSize(this.getSize());
pane.add(next, BorderLayout.EAST);
pane.add(previous, BorderLayout.WEST);
pane.add(page, BorderLayout.CENTER);
}
}
I would ideally like to keep the ratio of height to width constant.
Check out Darryl's Stretch Icon. It will shrink/grow depending on the space available, while maintaining the width/height ratio.
You can try overriding the paintComponent(Graphics g) method and drawing the resized image yourself.
page = new JLabel(loadIMG()){
#Override
paintComponent(Graphics g)
{
//So we don't kill default behaviour
super.paintComponent(g);
int scaledWidth, scaledHeight;
//pseudo-code
scale and store into scaledWidth and scaledHeight;
render with g.drawImage(icon, x, y, scaledWidth, scaledHeight, null);
}
};
Related
I'm building a simple 2D game in Java.
I'm using the JFrame class, but I don't think the width and height are what I specified, or perhaps the graphics are incorrect.
Here are some snippets of my code:
public final static int WIDTH = 600, HEIGHT = 900;
JFrame frame = new JFrame();
frame.setSize(WIDTH, HEIGHT);
g.setColor(Color.BLACK);
g.fillRect(0, 0, WIDTH, HEIGHT - 10);
The JFrame is displaying a black background. However, based on the arguments I gave to the fillRect function, there should still be a 10px tall sliver of white at the bottom of the frame. This is not the case. The white sliver only really starts to show after a 30px decrease from the height of the frame.
Thanks for your help.
The JFrame size includes the borders so you need to allow for them. To facilitate dealing with this don't specify the width and height of the JFrame. I recommend doing the following.
JFrame frame = new JFrame();
JPanel panel = new JPanel();
panel.setPreferredSize(new Dimension(width,height));
frame.add(panel);
// add other components in the panel
frame.pack();
// center on screen.
frame.setLocationRelativeTo(null);
frame.setVisible(true);
Now your panel will be the specified size.
Note, if your going to paint, make certain you override paintComponent(Graphics g) in JPanel and do your painting there.
#Override
public void paintComponent(Graphics g) {
super.paintComponent(g);
// your code here
}
I need to achieve the effect of "lights off" while displaying animation. It's currently been done with transparent Jframe, black background with 50% opacity the size of the monitor. then, there is this canvas component which should draw RGBA buffered-image.
Problems pops up when the the JFrame opacity effects the Canvas as well, making it semi transparent. That's what i'm trying to avoid.
//** Window class extends Canvas
public Window(){
GraphicsDevice gd = GraphicsEnvironment.getLocalGraphicsEnvironment().getDefaultScreenDevice();
int hostMonitorWidth = gd.getDisplayMode().getWidth();
int hostMonitorHeight = gd.getDisplayMode().getHeight();
Dimension dimension = new Dimension(hostMonitorWidth, hostMonitorHeight);
super.setPreferredSize(dimension);
window = new JFrame();
window.setUndecorated(true);
window.setOpacity(0.55f);
window.setLayout(new GridLayout());
window.setSize(hostMonitorWidth, hostMonitorHeight);
window.add(this);
window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
window.setLocationRelativeTo(null);
window.setVisible(true);
window.requestFocus();
window.setFocusableWindowState(true);
super.createBufferStrategy(3);
}
public void draw(){
BufferStrategy buffer = super.getBufferStrategy();
java.awt.Graphics g = buffer.getDrawGraphics();
g.setColor(Color.BLACK);
g.fillRect(0,0, super.getWidth(), super.getHeight());
g.drawImage(batch.getImage(), 0, 0, super.getWidth(), super.getHeight(), null);
g.dispose();
buffer.show();
}
I have tried couple combinations of the following code with Jpanel, Layered Panes, Jlabel and what not. It's always seems to keep the opacity / throwing unexplainable exceptions / not working for any reason.
Am i doing it the correct way? what am i missing here?
Don't use setOpacity, use setBackground on the JFrame and pass it a alpha based color. This will allow the frame to become transparent without affecting the other components.
You may, however, find that Canvas doesn't like alpha based colors (as it only has an opaque state)
I have a loaded image, but when I try to display it nothing is appearing.
public class JComponentButton extends JComponent implements MouseListener {
BufferedImage image;
public static void main(String[] args) {
JFrame mainFrame = new JFrame("Test Title3");
mainFrame.setSize(400,400);
mainFrame.setLayout(new GridLayout(1,1));
mainFrame.addWindowListener(new WindowAdapter() {
#Override public void windowClosing(WindowEvent windowEvent){
System.exit(0);
}
});
JPanel controlPanel = new JPanel();
controlPanel.setLayout(new FlowLayout());
JComponentButton button = new JComponentButton();
button.setSize(64,64);
controlPanel.add(button);
mainFrame.add(controlPanel);
mainFrame.setVisible(true);
System.out.println("finishing");
}
public JComponentButton(){
super();
try {
this.image = ImageIO.read(new File("resources/default.png"));
} catch (IOException e) {
System.out.println("did not load image");
System.exit(1);
}
enableInputMethods(true);
addMouseListener(this);
}
#Override public void paintComponent(Graphics g){
super.paintComponent(g);
System.out.println(image.getHeight() + "," + image.getWidth());
g.drawImage(image, 64, 64, null);
}
The image seems to be loaded as 64,64 is printed into the console. However where it should be appearing on the window is blank. I drew a square there without a problem using g.fillRect. So it seems like the problem has to be with g.drawImage. I also tried changing the perspective from null to this, but nothing changed.
In your code the method g.drawImage(image, 64, 64, null) will draw your image at it's full resolution starting at the offset at 64, 64.
Javadoc for drawImage:
Draws as much of the specified image as is currently available. The image is drawn with its top-left corner at (x, y) in this graphics context's coordinate space. Transparent pixels in the image do not affect whatever pixels are already there.
This means that whilst your image is indeed being drawn, it's being drawn outside the visible co-ordinate space of your button.
To fix the issue, replace the 64, 64 with 0, 0 if the image is sized at the component's size or use the more explicit method drawImage(Image img, int x, int y, int width, int height, ImageObserver observer) to specify what the image should be resized to whilst in the button.
E.g.
g.drawImage(image, 0, 0, null); //draws image at full resolution
g.drawImage(image, 0, 0, 64, 64, null); //draws image at offset 0, for max resolution of 64x64
You can't view the image is because the image is drawn outside of the button.
since you don't have any panel outside the button,it cannot be drawn.
The reason is,the x and y axis of the image that you have specified,i.e.Top left corner,are 64,64 and the button is of size 64,64.Thus,this image will be drawn at bottom right of the button,that is the corner point of the button.
Thus you should specify image points as 0,0 (these are the top-left corner of image) so that it will cover the 0,0(these are the top-left corner of button) point of the button.
Also,you must specify the width and height of the image.So,that it will not go out side of bounds of button.If you don't want to specify the width and height then you must decrease the pixels of the image to the size of button(at least).
you can rewrite the code as:
g.drawImage(image,0,0,64,64,null);
I have a JPanel with a size of 816 x 1056 pixels (size of a standard typewriting paper). Is there any way of displaying the whole JPanel and its content without altering its actual size, in a small JFrame? Is there a way of like zooming it out?
I can't think of an easy method to zoom a JPanel out, but you can do it via double-buffering:
private void paintPanel (Graphics2D g)
{
// here goes the code of your paint() or paintComponent() method
}
/** Draw content into an Image, shrink it, and display it. */
protected void paintComponent (Graphics g)
{
// paint image
BufferedImage img = new BufferedImage(MAX_WIDTH, MAX_HEIGHT, BufferedImage.TYPE_INT_ARGB);
paintPanel(img.createGraphics());
// shrink image and paint it
g.drawImage(img, 0,0, WIDTH,HEIGHT, 0,0, MAX_WIDTH,MAX_HEIGHT, null);
}
This will paint everything on a BufferedImage with the size MAX_WIDTH x MAX_HEIGHT. Then, the Image will be shrinked into the size WIDTH x HEIGHT and then displayed.
I am trying to learn Swing and have made a panel (with help from other StackOverflow code). I added a checkerboard design on a frame, but I have found that the frame is not as big as it should be.
Here is my code:
#Override
protected void paintComponent(Graphics g) {
int width = getWidth(), height = getHeight();
g.clearRect(0, 0, width, height);
g.setColor(Color.BLACK);
for (int i=0;i<=width;i+=50) {
g.drawLine(0,i,width,i);
}
for (int i=0;i<=height;i+=50) {
g.drawLine(i,0,i,height);
}
label.setText("H = "+ getHeight() +" W = "+ getWidth()); // check actual size
add(label);
}
private void gui(Pan window) {
frame = new JFrame();
Container container = frame.getContentPane();
container.add(window);
frame.setSize(400, 400); // size written here
frame.setVisible(true);
}
If you run it, you'll see the size of the window. It will be 362 by 384, instead of 400 by 400 as written in the code.
If I change the dimensions to 500 by 500, the window will be 462 by 484.
Q: Why are the dimensions off by 38 and 16?
It will be 362 by 384, instead of 400 by 400
Because the size of the frame include the title bar and borders. Don't use the setSize() method.
Instead override the getPreferredSize() method of your custom panel to return the size that you want the panel to be.
Then you use:
frame.pack();
Then the size of the frame will be the preferred size of your panel, plus the size of the title bar and borders.