I have following server side code in the top level page to set background image for all pages in the app.
#Override
public void createContent(final Composite parent, final PageData oData) {
Image bg = ResourceManager.getImage( LnfSettings.IMAGE_PAGE_BACKGROUND );
Composite comp = parent.getParent();
int width = comp.getDisplay().getClientArea().width;
int height = comp.getDisplay().getClientArea().height;
comp.setBackgroundImage( new Image( bg.getDevice(), bg.getImageData().scaledTo(
width, height ) ) );
... more code here to create layout and contents
}
Above code correctly sets background for all pages and also scaled image to fit with the different screen sizes. But if I rotate the screen, image doesn't get scaled according to the new screen dimension. How to deal with this issue? I am using Tabris 1.4.
You can add a resize listener to your composite like this:
comp.addListener(SWT.Resize, listenerComp);
Listener listenerComp = new Listener() {
#Override
public void handleEvent(Event event) {
...
}
};
Just get sure you cache your scaled Images so you do not scale and create new images on every rotation.
Related
Solution
Original: Window Service > Parent Layout > Views
Fixed: Window Service > Parent Layout > Parent Layout 2 > Views
You cannot use a parent layout that is not a child to another layout before being added to window service. Only graphics will scale if you do so.
Issue
I have a RelativeLayout that parents some views like a TextView, SeekBar, and a Button. Using setScaleX/Y, I am successfully able to scale the views visually. A problem I now have is that although the graphics have scaled, the onClickListeners touch area have not scaled along with the graphics. I need to touch the original position in order to trigger any of these events. I want the touch area to scale with the graphics without scaling the children individually.
Current Scaling Code:
size.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
#Override
public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
/** Max Progress is 100 **/
float scale = 1.0f;
scale = scale + 0.01f * progress;
/** mLayout is Parent Layout **/
mLayout.setScaleX(scale);
mLayout.setScaleY(scale);
mLayout.invalidate();
}
#Override
public void onStartTrackingTouch(SeekBar seekBar) {
}
#Override
public void onStopTrackingTouch(SeekBar seekBar) {
}
});
Solution
Original: Window Service > Parent Layout > Views
Fixed: Window Service > Parent Layout > Parent Layout 2 > Views
You cannot use a parent layout that is not a child to another layout before being added to window service. Only graphics will scale if you do so.
I want to write a new class that extends Region containing a StackPane inside. But I'm getting into trouble when I add insets to it like padding or a border. Here is a simplified example of the class:
public class CustomPane extends Region
{
private ToggleButton testControl = new ToggleButton("just a test control");
private StackPane rootPane = new StackPane(testControl);
public CustomPane()
{
getChildren().add(rootPane);
setStyle("-fx-border-color: #257165; -fx-border-width: 10;");
}
}
And that is how the result looks like:
If I try to move the StackPane by calling
rootPane.setLayoutX(10);
rootPane.setLayoutY(10);
then the Region just grows:
But really I wanted it to look like this:
(The third image was created by extending StackPane instead of Region, which already manages the layouting stuff correctly. Unfortunately I have to extend Region since I want to keep getChildren() protected.)
Okay, I tried to handle the layout calculation but I didn't come up with it. Could experts give me some advise?
StackPane uses the insets for layouting the (managed) children. Region doesn't do this by default. Therefore you need to override the layoutChildren with something that uses these insets, e.g.:
#Override
protected void layoutChildren() {
Insets insets = getInsets();
double top = insets.getTop(),
left = insets.getLeft(),
width = getWidth() - left - insets.getRight(),
height = getHeight() - top - insets.getBottom();
// layout all managed children (there's only rootPane in this case)
layoutInArea(rootPane,
left, top, // offset of layout area
width, height, // available size for content
0,
HPos.LEFT,
VPos.TOP);
}
I need to create a bufferedimage
(circular type) but I am able to create only rectangular type. Then I want to create a oval inside the bufferedimage with some configurations and finally i want to draw a rectangular icon inside the circular shape which should be inserted on the circular shape and not on the rectangular bufferedimage.
Now i am able to do the following
BufferedImage img = "SomeImage.png";
BufferedImage bfImage = new BufferedImage(200,200,BufferedImage.TYPE_INT_ARGB);
Graphics2D graphics = bfImage.createGraphics();
graphics.fillOval(0, 0, 200, 200);
graphics.drawImage(img, 0, 0, null);
(This creates a circular oval inside the bfImage object)
Now i need to draw "img" which is rectangular in shape of say 100*100 size.
This i can draw using
When i am doing this my final image is getting drawn in the Rectangular BfImage, which i dont want.I want the image "img" to be drawn in the circular oval and it should not come outside the boundaries of the circular oval shape.
In short instead of drawing my final image on the rectangular bfImage can i have a circular bfImage on which i can directly draw my image.
Any logic to do this in Java2D using graphics.
I've never encountered a "circular image" in the sense of a two dimensional array that is not in rectangular form. If all you are concerned about is that the pixels outside the circle are not visible, just set the alpha to 0 for those pixels. An easy way to do this is to fill the entire rectangular image with ARGB(0,0,0,0) first and then draw whatever else you want.
Also, not that if you intent to persist this buffer as an image file, you must make sure that you export/save to a format like PNG or TIFF that supports transparency.
As #justinzane says, you can't have a truly circular image. All BufferedImages will be rectangular.
But: You can achieve the effect you are after, by using the AlphaComposite class, and the rule AlphaComposite.SrcIn. I've added a fully running example, plus a screen shot below, the compose method is the important part.
public class AlphaCompositeTest {
private static BufferedImage compose(final BufferedImage source, int w, int h) {
BufferedImage destination = new BufferedImage(w, h, BufferedImage.TYPE_INT_ARGB);
Graphics2D graphics = destination.createGraphics();
try {
graphics.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
graphics.setColor(Color.BLACK); // The color here doesn't really matter
graphics.fillOval(0, 0, destination.getWidth(), destination.getHeight());
if (source != null) {
graphics.setComposite(AlphaComposite.SrcIn); // Only paint inside the oval from now on
graphics.drawImage(source, 0, 0, null);
}
}
finally {
graphics.dispose();
}
return destination;
}
public static void main(String[] args) throws IOException {
final BufferedImage original = ImageIO.read(new File("lena.png"));
final BufferedImage template = compose(null, original.getWidth(), original.getHeight());
final BufferedImage composed = compose(original, original.getWidth(), original.getHeight());
SwingUtilities.invokeLater(new Runnable() {
#Override public void run() {
JFrame frame = new JFrame();
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
JPanel panel = new JPanel(new BorderLayout(10, 10));
panel.add(new JLabel("+", new ImageIcon(template), SwingConstants.LEFT), BorderLayout.WEST);
panel.add(new JLabel("=", new ImageIcon(original), SwingConstants.LEFT), BorderLayout.CENTER);
panel.add(new JLabel(new ImageIcon(composed)), BorderLayout.EAST);
frame.add(new JScrollPane(panel));
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
}
See for example the Compositing tutorial for more info and examples.
I want to save the current state of the canvas as an image as I will use it in the next pointerevent. If I use repaint it will clear the canvas and I can't get the previous state of canvas. So, I want to save it as image and then iterate it over and over so that finally I can make out what I want.
The final question is how to save the canvas as image ?.
Or Is there any possibility of converting the Graphics object to a byte array ?
You can't save the canvas as an image.
You have to create an image first, and then you can paint onto that image.
Basically that means that your midlet will be doing more work, since you first have to draw onto your image, and then you have to draw that image onto the canvas. But it's the only way you can do what you want.
Create an Image with same size (width and height) of the screen. When you want to save the canvas state call Canvas.paint passing the image Graphics.
class MyCanvas extends Canvas {
private Image lastScreen;
protected void sizeChanged(int w, int h) {
if (lastScreen == null || w != lastScreen.getWidth()
|| h != lastScreen.getHeight) {
lastScreen = Image.createImage(w, h);
}
}
protected void paint(Graphics g) {
// paint the whole screen
}
protected void pointerReleased(int x, int y) {
paint(lastScreen.getGraphics());
}
}
I want to make a png Image as the background image of a LWUIT Form. The problem is that the image is altered : there are stains in the image after setting it as the Form's background image. Here are codes :
public class DetailPhotoClient extends Form implements ActionListener {
private Command options, delete, back, annuler, ok;
private GaleriePhotos backForm;
private FileConnection fcFile;
private Image sourceImage, fullImage;
private InputStream is;
private PopupMenu popup;
public DetailPhotoClient(GaleriePhotos prevForm, String absolutePathphotoName)
{
super();
back = new Command("Retour");
options = new Command("Options");
this.addCommand(back);
this.addCommand(options);
this.addCommandListener(this);
delete = new Command("Supprimer");
annuler = new Command("Annuler");
ok = new Command("Ok");
backForm = prevForm;
try {
fcFile = (FileConnection) Connector.open(absolutePathphotoName, Connector.READ);
is = fcFile.openInputStream();
sourceImage = Image.createImage(is);
fullImage = createThumbnail(sourceImage);
setBgImage(fullImage);
is.close();
fcFile.close();
} catch (IOException ex) {
handleException();
} catch (OutOfMemoryError oom) {
handleOOM();
}
}
private Image createThumbnail(Image image) {
Image thumb = image.scaled(this.getPreferredW(), this.getPreferredH());
return thumb;
}
...
}
I noticed that when I open the photo manually , that is from the phone memory's photo folder , then the photo is not altered !
So how to make the image not altered when setting it as the Form's background image ?
LWUIT uses scaling for background images by default. It will always scale the images unless you explicitly ask the style for different behavior e.g. tiling, aligning etc. try:
myForm.getStyle().setBackgroundType(Style.BACKGROUND_IMAGE_ALIGNED_CENTER);
Validate whether the image read from file, i.e. sourceImage, is as seen in the native phone device. If not so the problem lies here.
If you are able to see the sourceImage correct, than there are some things to be evaluated in getting a scaled image.
In case your form contentPane's width / height is smaller than the images width / height than a better option would be use
Image thumb = image.scaledSmallerRatio(this.getWidth(), this.getHeight());
NOTE: Yes, its getWidth() and not getPreferredW(). If you don't get desired result than try scaling with getPreferredW().
In case your image's width / height is smaller than form contentPane's width / height, you might as well do not scale it since the image will fit the screen.