Example usage for org.eclipse.swt.widgets Canvas redraw

List of usage examples for org.eclipse.swt.widgets Canvas redraw

Introduction

In this page you can find the example usage for org.eclipse.swt.widgets Canvas redraw.

Prototype

public void redraw() 

Source Link

Document

Causes the entire bounds of the receiver to be marked as needing to be redrawn.

Usage

From source file:BrowserExample.java

/**
 * Creates an instance of a ControlExample embedded inside the supplied
 * parent Composite./*  w  w  w  .  j  a v  a  2  s . co  m*/
 * 
 * @param parent
 *            the container of the example
 */
public BrowserExample(Composite parent) {

    final Display display = parent.getDisplay();
    FormLayout layout = new FormLayout();
    parent.setLayout(layout);
    ToolBar toolbar = new ToolBar(parent, SWT.NONE);
    final ToolItem itemBack = new ToolItem(toolbar, SWT.PUSH);
    itemBack.setText(getResourceString("Back"));
    final ToolItem itemForward = new ToolItem(toolbar, SWT.PUSH);
    itemForward.setText(getResourceString("Forward"));
    final ToolItem itemStop = new ToolItem(toolbar, SWT.PUSH);
    itemStop.setText(getResourceString("Stop"));
    final ToolItem itemRefresh = new ToolItem(toolbar, SWT.PUSH);
    itemRefresh.setText(getResourceString("Refresh"));
    final ToolItem itemGo = new ToolItem(toolbar, SWT.PUSH);
    itemGo.setText(getResourceString("Go"));

    location = new Text(parent, SWT.BORDER);

    images = new Image[] { new Image(display, "java2s.gif") };

    final Canvas canvas = new Canvas(parent, SWT.NO_BACKGROUND);
    final Rectangle rect = images[0].getBounds();
    canvas.addListener(SWT.Paint, new Listener() {
        public void handleEvent(Event e) {
            Point pt = canvas.getSize();
            e.gc.drawImage(images[index], 0, 0, rect.width, rect.height, 0, 0, pt.x, pt.y);
        }
    });
    canvas.addListener(SWT.MouseDown, new Listener() {
        public void handleEvent(Event e) {
            browser.setUrl(getResourceString("Startup"));
        }
    });

    display.asyncExec(new Runnable() {
        public void run() {
            if (canvas.isDisposed())
                return;
            if (busy) {
                index++;
                if (index == images.length)
                    index = 0;
                canvas.redraw();
            }
            display.timerExec(150, this);
        }
    });

    final Label status = new Label(parent, SWT.NONE);
    final ProgressBar progressBar = new ProgressBar(parent, SWT.NONE);

    FormData data = new FormData();
    data.top = new FormAttachment(0, 5);
    toolbar.setLayoutData(data);

    data = new FormData();
    data.left = new FormAttachment(0, 0);
    data.right = new FormAttachment(100, 0);
    data.top = new FormAttachment(canvas, 5, SWT.DEFAULT);
    data.bottom = new FormAttachment(status, -5, SWT.DEFAULT);
    try {
        browser = new Browser(parent, SWT.NONE);
        browser.setLayoutData(data);
    } catch (SWTError e) {
        /* Browser widget could not be instantiated */
        Label label = new Label(parent, SWT.CENTER | SWT.WRAP);
        label.setText(getResourceString("BrowserNotCreated"));
        label.setLayoutData(data);
    }

    data = new FormData();
    data.width = 24;
    data.height = 24;
    data.top = new FormAttachment(0, 5);
    data.right = new FormAttachment(100, -5);
    canvas.setLayoutData(data);

    data = new FormData();
    data.top = new FormAttachment(toolbar, 0, SWT.TOP);
    data.left = new FormAttachment(toolbar, 5, SWT.RIGHT);
    data.right = new FormAttachment(canvas, -5, SWT.DEFAULT);
    location.setLayoutData(data);

    data = new FormData();
    data.left = new FormAttachment(0, 5);
    data.right = new FormAttachment(progressBar, 0, SWT.DEFAULT);
    data.bottom = new FormAttachment(100, -5);
    status.setLayoutData(data);

    data = new FormData();
    data.right = new FormAttachment(100, -5);
    data.bottom = new FormAttachment(100, -5);
    progressBar.setLayoutData(data);

    if (browser != null) {
        itemBack.setEnabled(browser.isBackEnabled());
        itemForward.setEnabled(browser.isForwardEnabled());

        Listener listener = new Listener() {
            public void handleEvent(Event event) {
                ToolItem item = (ToolItem) event.widget;
                if (item == itemBack)
                    browser.back();
                else if (item == itemForward)
                    browser.forward();
                else if (item == itemStop)
                    browser.stop();
                else if (item == itemRefresh)
                    browser.refresh();
                else if (item == itemGo)
                    browser.setUrl(location.getText());
            }
        };
        browser.addLocationListener(new LocationListener() {
            public void changed(LocationEvent event) {
                busy = true;
                if (event.top)
                    location.setText(event.location);
            }

            public void changing(LocationEvent event) {
            }
        });
        browser.addProgressListener(new ProgressListener() {
            public void changed(ProgressEvent event) {
                if (event.total == 0)
                    return;
                int ratio = event.current * 100 / event.total;
                progressBar.setSelection(ratio);
                busy = event.current != event.total;
                if (!busy) {
                    index = 0;
                    canvas.redraw();
                }
            }

            public void completed(ProgressEvent event) {
                itemBack.setEnabled(browser.isBackEnabled());
                itemForward.setEnabled(browser.isForwardEnabled());
                progressBar.setSelection(0);
                busy = false;
                index = 0;
                canvas.redraw();
            }
        });
        browser.addStatusTextListener(new StatusTextListener() {
            public void changed(StatusTextEvent event) {
                status.setText(event.text);
            }
        });
        if (parent instanceof Shell) {
            final Shell shell = (Shell) parent;
            browser.addTitleListener(new TitleListener() {
                public void changed(TitleEvent event) {
                    shell.setText(event.title + " - " + getResourceString("window.title"));
                }
            });
        }
        itemBack.addListener(SWT.Selection, listener);
        itemForward.addListener(SWT.Selection, listener);
        itemStop.addListener(SWT.Selection, listener);
        itemRefresh.addListener(SWT.Selection, listener);
        itemGo.addListener(SWT.Selection, listener);
        location.addListener(SWT.DefaultSelection, new Listener() {
            public void handleEvent(Event e) {
                browser.setUrl(location.getText());
            }
        });

        initialize(display, browser);
        browser.setUrl(getResourceString("Startup"));
    }
}

From source file:DoubleBuffer.java

public DoubleBuffer() {
    shell.setLayout(new FillLayout());

    final Image imageEclipse = new Image(display, "java2s.gif");

    //      final Canvas canvas = new Canvas(shell, SWT.NULL);
    //      canvas.addPaintListener(new PaintListener() {
    //         public void paintControl(PaintEvent e) {
    //            Point size = canvas.getSize();
    //// w  w w.j  a  v  a  2 s.c o  m
    //            int x1 = (int) (Math.random() * size.x);
    //            int y1 = (int) (Math.random() * size.y);
    //            int x2 = Math.max(canvas.getBounds().width - x1 - 10, 50);
    //            int y2 = Math.max(canvas.getBounds().height - y1 - 10, 50);
    //
    //            
    //            e.gc.drawRoundRectangle(x1, y1, x2, y2, 5, 5);
    //
    //            display.timerExec(100, new Runnable() {
    //               public void run() {
    //                  canvas.redraw();
    //               }
    //            });
    //            
    //         }
    //      });

    final Canvas doubleBufferedCanvas = new Canvas(shell, SWT.NO_BACKGROUND);

    doubleBufferedCanvas.addPaintListener(new PaintListener() {
        public void paintControl(PaintEvent e) {
            // Creates new image only absolutely necessary.
            Image image = (Image) doubleBufferedCanvas.getData("double-buffer-image");
            if (image == null || image.getBounds().width != doubleBufferedCanvas.getSize().x
                    || image.getBounds().height != doubleBufferedCanvas.getSize().y) {
                image = new Image(display, doubleBufferedCanvas.getSize().x, doubleBufferedCanvas.getSize().y);
                doubleBufferedCanvas.setData("double-buffer-image", image);
            }

            // Initializes the graphics context of the image. 
            GC imageGC = new GC(image);
            imageGC.setBackground(e.gc.getBackground());
            imageGC.setForeground(e.gc.getForeground());
            imageGC.setFont(e.gc.getFont());

            // Fills background. 
            Rectangle imageSize = image.getBounds();
            imageGC.fillRectangle(0, 0, imageSize.width + 1, imageSize.height + 1);

            // Performs actual drawing here ...
            Point size = doubleBufferedCanvas.getSize();

            int x1 = (int) (Math.random() * size.x);
            int y1 = (int) (Math.random() * size.y);
            int x2 = Math.max(doubleBufferedCanvas.getBounds().width - x1 - 10, 50);
            int y2 = Math.max(doubleBufferedCanvas.getBounds().height - y1 - 10, 50);

            imageGC.drawRoundRectangle(x1, y1, x2, y2, 5, 5);

            // Draws the buffer image onto the canvas. 
            e.gc.drawImage(image, 0, 0);

            imageGC.dispose();

            display.timerExec(100, new Runnable() {
                public void run() {
                    doubleBufferedCanvas.redraw();
                }
            });
        }
    });

    shell.setSize(300, 200);
    shell.open();
    //textUser.forceFocus();

    // Set up the event loop.
    while (!shell.isDisposed()) {
        if (!display.readAndDispatch()) {
            // If no more entries in event queue
            display.sleep();
        }
    }

    display.dispose();
}

From source file:Extents.java

/**
 * Creates the main window's contents//from   w  ww .  j a  v a 2 s  . co m
 * 
 * @param shell the main window
 */
private void createContents(final Shell shell) {
    // Create a canvas to draw on
    final Canvas canvas = new Canvas(shell, SWT.NONE);

    // Add a listener to the shell to resize the canvas to fill the window
    // any time the window is resized
    shell.addControlListener(new ControlAdapter() {
        public void controlResized(ControlEvent event) {
            canvas.setBounds(shell.getClientArea());
        }
    });

    // Add a listener to the canvas. This is where we draw the text.
    canvas.addPaintListener(new PaintListener() {
        public void paintControl(PaintEvent event) {
            // Set the font into the gc
            event.gc.setFont(font);

            // Calcalute the width (nad height) of the string
            Point pt = event.gc.stringExtent(STRING);

            // Figure out how big our drawing area is
            Rectangle rect = canvas.getBounds();

            // Calculate the height of the font. We could have used pt.y,
            // but this demonstrates FontMetrics
            int height = event.gc.getFontMetrics().getHeight();

            // Outside loop goes from the top of the window to the bottom.
            // Since the (x, y) passed to drawString represents the upper left
            // corner, subtract the height of the font from the height of the
            // drawing area, so we don't have any partial drawing.
            for (int i = 0, n = rect.height - height; i < n; i += height) {
                // Inside loop goes from the left to the right, stopping far enough
                // from the right to ensure no partial string drawing.
                for (int j = 0, m = rect.width - pt.x; j < m; j += pt.x) {
                    // Draw the string
                    event.gc.drawString(STRING, j, i);
                }
            }
        }
    });

    // Create an editor to house the dropdown
    ControlEditor editor = new ControlEditor(canvas);

    // Create the combo and fill it
    final Combo combo = new Combo(canvas, SWT.READ_ONLY);
    for (int i = 0, n = SIZES.length; i < n; i++) {
        combo.add(SIZES[i]);
    }

    // Set up the editor
    editor.horizontalAlignment = SWT.CENTER;
    editor.verticalAlignment = SWT.TOP;
    Point size = combo.computeSize(SWT.DEFAULT, SWT.DEFAULT);
    editor.minimumWidth = size.x;
    editor.minimumHeight = size.y;
    editor.setEditor(combo);

    // Add a listener to the combo, so that when the selection changes,
    // we change the font and redraw the canvas
    combo.addSelectionListener(new SelectionAdapter() {
        public void widgetSelected(SelectionEvent event) {
            if (font != null)
                font.dispose();
            font = new Font(shell.getDisplay(), "Helvetica", new Integer(combo.getText()).intValue(), SWT.BOLD);
            canvas.redraw();
        }
    });

    // Select the first item in the combo
    combo.select(0);
}

From source file:org.eclipse.swt.examples.clipboard.ClipboardExample.java

void createImageTransfer(Composite copyParent, Composite pasteParent) {
    final Image[] copyImage = new Image[] { null };
    Label l = new Label(copyParent, SWT.NONE);
    l.setText("ImageTransfer:"); //$NON-NLS-1$
    GridData data = new GridData();
    data.verticalSpan = 2;/*w ww  . ja va 2 s.  c  o m*/
    l.setLayoutData(data);

    final Canvas copyImageCanvas = new Canvas(copyParent, SWT.BORDER | SWT.V_SCROLL | SWT.H_SCROLL);
    data = new GridData(GridData.FILL_BOTH);
    data.verticalSpan = 2;
    data.widthHint = HSIZE;
    data.heightHint = VSIZE;
    copyImageCanvas.setLayoutData(data);

    final Point copyOrigin = new Point(0, 0);
    final ScrollBar copyHBar = copyImageCanvas.getHorizontalBar();
    copyHBar.setEnabled(false);
    copyHBar.addListener(SWT.Selection, e -> {
        if (copyImage[0] != null) {
            int hSelection = copyHBar.getSelection();
            int destX = -hSelection - copyOrigin.x;
            Rectangle rect = copyImage[0].getBounds();
            copyImageCanvas.scroll(destX, 0, 0, 0, rect.width, rect.height, false);
            copyOrigin.x = -hSelection;
        }
    });
    final ScrollBar copyVBar = copyImageCanvas.getVerticalBar();
    copyVBar.setEnabled(false);
    copyVBar.addListener(SWT.Selection, e -> {
        if (copyImage[0] != null) {
            int vSelection = copyVBar.getSelection();
            int destY = -vSelection - copyOrigin.y;
            Rectangle rect = copyImage[0].getBounds();
            copyImageCanvas.scroll(0, destY, 0, 0, rect.width, rect.height, false);
            copyOrigin.y = -vSelection;
        }
    });
    copyImageCanvas.addListener(SWT.Paint, e -> {
        if (copyImage[0] != null) {
            GC gc = e.gc;
            gc.drawImage(copyImage[0], copyOrigin.x, copyOrigin.y);
            Rectangle rect = copyImage[0].getBounds();
            Rectangle client = copyImageCanvas.getClientArea();
            int marginWidth = client.width - rect.width;
            if (marginWidth > 0) {
                gc.fillRectangle(rect.width, 0, marginWidth, client.height);
            }
            int marginHeight = client.height - rect.height;
            if (marginHeight > 0) {
                gc.fillRectangle(0, rect.height, client.width, marginHeight);
            }
            gc.dispose();
        }
    });
    Button openButton = new Button(copyParent, SWT.PUSH);
    openButton.setText("Open Image");
    openButton.addSelectionListener(widgetSelectedAdapter(e -> {
        FileDialog dialog = new FileDialog(shell, SWT.OPEN);
        dialog.setText("Open an image file or cancel");
        String string = dialog.open();
        if (string != null) {
            if (copyImage[0] != null) {
                System.out.println("CopyImage");
                copyImage[0].dispose();
            }
            copyImage[0] = new Image(e.display, string);
            copyVBar.setEnabled(true);
            copyHBar.setEnabled(true);
            copyOrigin.x = 0;
            copyOrigin.y = 0;
            Rectangle rect = copyImage[0].getBounds();
            Rectangle client = copyImageCanvas.getClientArea();
            copyHBar.setMaximum(rect.width);
            copyVBar.setMaximum(rect.height);
            copyHBar.setThumb(Math.min(rect.width, client.width));
            copyVBar.setThumb(Math.min(rect.height, client.height));
            copyImageCanvas.scroll(0, 0, 0, 0, rect.width, rect.height, true);
            copyVBar.setSelection(0);
            copyHBar.setSelection(0);
            copyImageCanvas.redraw();
        }
    }));
    Button b = new Button(copyParent, SWT.PUSH);
    b.setText("Copy");
    b.addSelectionListener(widgetSelectedAdapter(e -> {
        if (copyImage[0] != null) {
            status.setText("");
            // Fetch ImageData at current zoom and save in the clip-board.
            clipboard.setContents(new Object[] { copyImage[0].getImageDataAtCurrentZoom() },
                    new Transfer[] { ImageTransfer.getInstance() });
        } else {
            status.setText("No image to copy");
        }
    }));

    final Image[] pasteImage = new Image[] { null };
    l = new Label(pasteParent, SWT.NONE);
    l.setText("ImageTransfer:");
    final Canvas pasteImageCanvas = new Canvas(pasteParent, SWT.BORDER | SWT.V_SCROLL | SWT.H_SCROLL);
    data = new GridData(GridData.FILL_BOTH);
    data.widthHint = HSIZE;
    data.heightHint = VSIZE;
    pasteImageCanvas.setLayoutData(data);
    final Point pasteOrigin = new Point(0, 0);
    final ScrollBar pasteHBar = pasteImageCanvas.getHorizontalBar();
    pasteHBar.setEnabled(false);
    pasteHBar.addListener(SWT.Selection, e -> {
        if (pasteImage[0] != null) {
            int hSelection = pasteHBar.getSelection();
            int destX = -hSelection - pasteOrigin.x;
            Rectangle rect = pasteImage[0].getBounds();
            pasteImageCanvas.scroll(destX, 0, 0, 0, rect.width, rect.height, false);
            pasteOrigin.x = -hSelection;
        }
    });
    final ScrollBar pasteVBar = pasteImageCanvas.getVerticalBar();
    pasteVBar.setEnabled(false);
    pasteVBar.addListener(SWT.Selection, e -> {
        if (pasteImage[0] != null) {
            int vSelection = pasteVBar.getSelection();
            int destY = -vSelection - pasteOrigin.y;
            Rectangle rect = pasteImage[0].getBounds();
            pasteImageCanvas.scroll(0, destY, 0, 0, rect.width, rect.height, false);
            pasteOrigin.y = -vSelection;
        }
    });
    pasteImageCanvas.addListener(SWT.Paint, e -> {
        if (pasteImage[0] != null) {
            GC gc = e.gc;
            gc.drawImage(pasteImage[0], pasteOrigin.x, pasteOrigin.y);
            Rectangle rect = pasteImage[0].getBounds();
            Rectangle client = pasteImageCanvas.getClientArea();
            int marginWidth = client.width - rect.width;
            if (marginWidth > 0) {
                gc.fillRectangle(rect.width, 0, marginWidth, client.height);
            }
            int marginHeight = client.height - rect.height;
            if (marginHeight > 0) {
                gc.fillRectangle(0, rect.height, client.width, marginHeight);
            }
        }
    });
    b = new Button(pasteParent, SWT.PUSH);
    b.setText("Paste");
    b.addSelectionListener(widgetSelectedAdapter(e -> {
        ImageData imageData = (ImageData) clipboard.getContents(ImageTransfer.getInstance());
        if (imageData != null) {
            if (pasteImage[0] != null) {
                System.out.println("PasteImage");
                pasteImage[0].dispose();
            }
            status.setText("");
            // Consume the ImageData at current zoom as-is.
            pasteImage[0] = new Image(e.display, new AutoScaleImageDataProvider(imageData));
            pasteVBar.setEnabled(true);
            pasteHBar.setEnabled(true);
            pasteOrigin.x = 0;
            pasteOrigin.y = 0;
            Rectangle rect = pasteImage[0].getBounds();
            Rectangle client = pasteImageCanvas.getClientArea();
            pasteHBar.setMaximum(rect.width);
            pasteVBar.setMaximum(rect.height);
            pasteHBar.setThumb(Math.min(rect.width, client.width));
            pasteVBar.setThumb(Math.min(rect.height, client.height));
            pasteImageCanvas.scroll(0, 0, 0, 0, rect.width, rect.height, true);
            pasteVBar.setSelection(0);
            pasteHBar.setSelection(0);
            pasteImageCanvas.redraw();
        } else {
            status.setText("No image to paste");
        }
    }));
}