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

Introduction

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

Prototype

public Rectangle getClientArea() 

Source Link

Document

Returns a rectangle which describes the area of the receiver which is capable of displaying data (that is, not covered by the "trimmings").

Usage

From source file:org.eclipse.swt.examples.accessibility.AccessibleValueExample.java

public static void main(String[] args) {
    Display display = new Display();
    Shell shell = new Shell(display);
    shell.setLayout(new FillLayout());
    shell.setText("Accessible Value Example");

    final Canvas canvas = new Canvas(shell, SWT.DOUBLE_BUFFERED);
    canvas.addPaintListener(e -> {/*from   w  ww .  j av  a 2  s  . c  om*/
        Rectangle rect = canvas.getClientArea();
        String val = String.valueOf(value);
        Point size = e.gc.stringExtent(val);
        e.gc.setBackground(e.display.getSystemColor(SWT.COLOR_LIST_SELECTION));
        e.gc.fillRectangle(0, 0, rect.width * value / (max - min), rect.height);
        e.gc.drawString(val, rect.x + (rect.width - size.x) / 2, rect.y + (rect.height - size.y) / 2, true);
    });

    Accessible accessible = canvas.getAccessible();
    accessible.addAccessibleListener(new AccessibleAdapter() {
        @Override
        public void getName(AccessibleEvent e) {
            e.result = "The value of this canvas is " + value;
        }
    });
    accessible.addAccessibleControlListener(new AccessibleControlAdapter() {
        @Override
        public void getRole(AccessibleControlEvent e) {
            e.detail = ACC.ROLE_PROGRESSBAR;
        }
    });
    accessible.addAccessibleValueListener(new AccessibleValueAdapter() {
        @Override
        public void setCurrentValue(AccessibleValueEvent e) {
            value = e.value.intValue();
            canvas.redraw();
        }

        @Override
        public void getMinimumValue(AccessibleValueEvent e) {
            e.value = Integer.valueOf(min);
        }

        @Override
        public void getMaximumValue(AccessibleValueEvent e) {
            e.value = Integer.valueOf(max);
        }

        @Override
        public void getCurrentValue(AccessibleValueEvent e) {
            e.value = Integer.valueOf(value);
        }
    });

    shell.pack();
    shell.open();
    while (!shell.isDisposed()) {
        if (!display.readAndDispatch())
            display.sleep();
    }
    display.dispose();
}

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From source file:CanvasKeyEvent.java

public static void main(String[] args) {
    final Display display = new Display();
    Shell shell = new Shell(display);

    shell.setLayout(new RowLayout());
    final Canvas canvas = new Canvas(shell, SWT.NULL);
    canvas.setSize(500, 500);//from  w  ww.  java2  s .c  om
    canvas.setBackground(display.getSystemColor(SWT.COLOR_YELLOW));

    canvas.addKeyListener(new KeyListener() {
        public void keyPressed(KeyEvent e) {
            GC gc = new GC(canvas);
            Rectangle rect = canvas.getClientArea();
            gc.fillRectangle(rect.x, rect.y, rect.width, rect.height);

            Font font = new Font(display, "Arial", 32, SWT.BOLD);
            gc.setFont(font);

            gc.drawString("" + e.character, 15, 10);

            gc.dispose();
            font.dispose();
        }

        public void keyReleased(KeyEvent e) {
        }
    });

    shell.open();
    while (!shell.isDisposed()) {
        if (!display.readAndDispatch()) {
            display.sleep();
        }
    }
}

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From source file:org.eclipse.swt.examples.accessibility.AccessibleActionExample.java

public static void main(String[] args) {
    Display display = new Display();
    Shell shell = new Shell(display);
    shell.setLayout(new FillLayout());
    shell.setText("Accessible Action Example");

    Button button = new Button(shell, SWT.PUSH);
    button.setText("Button");

    final Canvas customButton = new Canvas(shell, SWT.NONE) {
        @Override//from   w  ww  .j ava 2s  . c o  m
        public Point computeSize(int wHint, int hHint, boolean changed) {
            GC gc = new GC(this);
            Point point = gc.stringExtent(buttonText);
            gc.dispose();
            point.x += MARGIN;
            point.y += MARGIN;
            return point;
        }
    };
    customButton.addPaintListener(e -> {
        Rectangle clientArea = customButton.getClientArea();
        Point stringExtent = e.gc.stringExtent(buttonText);
        int x = clientArea.x + (clientArea.width - stringExtent.x) / 2;
        int y = clientArea.y + (clientArea.height - stringExtent.y) / 2;
        e.gc.drawString(buttonText, x, y);
    });
    customButton.addMouseListener(MouseListener.mouseDownAdapter(e -> {
        int actionIndex = (e.button == 1) ? 0 : 1;
        customButtonAction(actionIndex);
    }));
    customButton.addKeyListener(new KeyAdapter() {
        @Override
        public void keyPressed(KeyEvent e) {
            int modifierKeys = e.stateMask & SWT.MODIFIER_MASK;
            if (modifierKeys == SWT.CTRL || modifierKeys == 0) {
                if (e.character == '1')
                    customButtonAction(0);
                else if (e.character == '2')
                    customButtonAction(1);
            }
        }
    });

    Accessible accessible = customButton.getAccessible();
    accessible.addAccessibleListener(new AccessibleAdapter() {
        @Override
        public void getName(AccessibleEvent e) {
            e.result = buttonText;
        }

        @Override
        public void getKeyboardShortcut(AccessibleEvent e) {
            e.result = "CTRL+1"; // default action is 'action 1'
        }
    });
    accessible.addAccessibleControlListener(new AccessibleControlAdapter() {
        @Override
        public void getRole(AccessibleControlEvent e) {
            e.detail = ACC.ROLE_PUSHBUTTON;
        }
    });
    accessible.addAccessibleActionListener(new AccessibleActionAdapter() {
        @Override
        public void getActionCount(AccessibleActionEvent e) {
            e.count = 2;
        }

        @Override
        public void getName(AccessibleActionEvent e) {
            if (0 <= e.index && e.index <= 1) {
                if (e.localized) {
                    e.result = AccessibleActionExample.getResourceString("action" + e.index);
                } else {
                    e.result = "Action" + e.index; //$NON-NLS-1$
                }
            }
        }

        @Override
        public void getDescription(AccessibleActionEvent e) {
            if (0 <= e.index && e.index <= 1) {
                e.result = AccessibleActionExample.getResourceString("action" + e.index + "description");
            }
        }

        @Override
        public void doAction(AccessibleActionEvent e) {
            if (0 <= e.index && e.index <= 1) {
                customButtonAction(e.index);
                e.result = ACC.OK;
            }
        }

        @Override
        public void getKeyBinding(AccessibleActionEvent e) {
            switch (e.index) {
            case 0:
                e.result = "1;CTRL+1";
                break;
            case 1:
                e.result = "2;CTRL+2";
                break;
            default:
                e.result = null;
            }
        }
    });

    shell.pack();
    shell.open();
    while (!shell.isDisposed()) {
        if (!display.readAndDispatch())
            display.sleep();
    }
    display.dispose();
}

---

From source file:org.eclipse.swt.snippets.Snippet48.java

public static void main(String[] args) {
    Display display = new Display();
    Shell shell = new Shell(display);
    shell.setText("Snippet 48");
    shell.setLayout(new FillLayout());
    Image originalImage = null;//from  w  w w  .  ja v  a2 s.  c  o m
    FileDialog dialog = new FileDialog(shell, SWT.OPEN);
    dialog.setText("Open an image file or cancel");
    String string = dialog.open();
    if (string != null) {
        originalImage = new Image(display, string);
    }
    if (originalImage == null) {
        int width = 150, height = 200;
        originalImage = new Image(display, width, height);
        GC gc = new GC(originalImage);
        gc.fillRectangle(0, 0, width, height);
        gc.drawLine(0, 0, width, height);
        gc.drawLine(0, height, width, 0);
        gc.drawText("Default Image", 10, 10);
        gc.dispose();
    }
    final Image image = originalImage;
    final Point origin = new Point(0, 0);
    final Canvas canvas = new Canvas(shell,
            SWT.NO_BACKGROUND | SWT.NO_REDRAW_RESIZE | SWT.V_SCROLL | SWT.H_SCROLL);
    final ScrollBar hBar = canvas.getHorizontalBar();
    hBar.addListener(SWT.Selection, e -> {
        int hSelection = hBar.getSelection();
        int destX = -hSelection - origin.x;
        Rectangle rect = image.getBounds();
        canvas.scroll(destX, 0, 0, 0, rect.width, rect.height, false);
        origin.x = -hSelection;
    });
    final ScrollBar vBar = canvas.getVerticalBar();
    vBar.addListener(SWT.Selection, e -> {
        int vSelection = vBar.getSelection();
        int destY = -vSelection - origin.y;
        Rectangle rect = image.getBounds();
        canvas.scroll(0, destY, 0, 0, rect.width, rect.height, false);
        origin.y = -vSelection;
    });
    canvas.addListener(SWT.Resize, e -> {
        Rectangle rect = image.getBounds();
        Rectangle client = canvas.getClientArea();
        hBar.setMaximum(rect.width);
        vBar.setMaximum(rect.height);
        hBar.setThumb(Math.min(rect.width, client.width));
        vBar.setThumb(Math.min(rect.height, client.height));
        int hPage = rect.width - client.width;
        int vPage = rect.height - client.height;
        int hSelection = hBar.getSelection();
        int vSelection = vBar.getSelection();
        if (hSelection >= hPage) {
            if (hPage <= 0)
                hSelection = 0;
            origin.x = -hSelection;
        }
        if (vSelection >= vPage) {
            if (vPage <= 0)
                vSelection = 0;
            origin.y = -vSelection;
        }
        canvas.redraw();
    });
    canvas.addListener(SWT.Paint, e -> {
        GC gc = e.gc;
        gc.drawImage(image, origin.x, origin.y);
        Rectangle rect = image.getBounds();
        Rectangle client = canvas.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);
        }
    });
    Rectangle rect = image.getBounds();
    shell.setSize(Math.max(200, rect.width - 100), Math.max(150, rect.height - 100));
    shell.open();
    while (!shell.isDisposed()) {
        if (!display.readAndDispatch())
            display.sleep();
    }
    originalImage.dispose();
    display.dispose();
}

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From source file:ImageScrollFlickerFree.java

public static void main(String[] args) {
    Display display = new Display();
    Shell shell = new Shell(display);
    shell.setLayout(new FillLayout());
    Image originalImage = null;/*from ww  w.j ava 2  s .c  o  m*/
    FileDialog dialog = new FileDialog(shell, SWT.OPEN);
    dialog.setText("Open an image file or cancel");
    String string = dialog.open();
    if (string != null) {
        originalImage = new Image(display, string);
    }
    if (originalImage == null) {
        int width = 150, height = 200;
        originalImage = new Image(display, width, height);
        GC gc = new GC(originalImage);
        gc.fillRectangle(0, 0, width, height);
        gc.drawLine(0, 0, width, height);
        gc.drawLine(0, height, width, 0);
        gc.drawText("Default Image", 10, 10);
        gc.dispose();
    }
    final Image image = originalImage;
    final Point origin = new Point(0, 0);
    final Canvas canvas = new Canvas(shell,
            SWT.NO_BACKGROUND | SWT.NO_REDRAW_RESIZE | SWT.V_SCROLL | SWT.H_SCROLL);
    final ScrollBar hBar = canvas.getHorizontalBar();
    hBar.addListener(SWT.Selection, new Listener() {
        public void handleEvent(Event e) {
            int hSelection = hBar.getSelection();
            int destX = -hSelection - origin.x;
            Rectangle rect = image.getBounds();
            canvas.scroll(destX, 0, 0, 0, rect.width, rect.height, false);
            origin.x = -hSelection;
        }
    });
    final ScrollBar vBar = canvas.getVerticalBar();
    vBar.addListener(SWT.Selection, new Listener() {
        public void handleEvent(Event e) {
            int vSelection = vBar.getSelection();
            int destY = -vSelection - origin.y;
            Rectangle rect = image.getBounds();
            canvas.scroll(0, destY, 0, 0, rect.width, rect.height, false);
            origin.y = -vSelection;
        }
    });
    canvas.addListener(SWT.Resize, new Listener() {
        public void handleEvent(Event e) {
            Rectangle rect = image.getBounds();
            Rectangle client = canvas.getClientArea();
            hBar.setMaximum(rect.width);
            vBar.setMaximum(rect.height);
            hBar.setThumb(Math.min(rect.width, client.width));
            vBar.setThumb(Math.min(rect.height, client.height));
            int hPage = rect.width - client.width;
            int vPage = rect.height - client.height;
            int hSelection = hBar.getSelection();
            int vSelection = vBar.getSelection();
            if (hSelection >= hPage) {
                if (hPage <= 0)
                    hSelection = 0;
                origin.x = -hSelection;
            }
            if (vSelection >= vPage) {
                if (vPage <= 0)
                    vSelection = 0;
                origin.y = -vSelection;
            }
            canvas.redraw();
        }
    });
    canvas.addListener(SWT.Paint, new Listener() {
        public void handleEvent(Event e) {
            GC gc = e.gc;
            gc.drawImage(image, origin.x, origin.y);
            Rectangle rect = image.getBounds();
            Rectangle client = canvas.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);
            }
        }
    });
    shell.setSize(200, 150);
    shell.open();
    while (!shell.isDisposed()) {
        if (!display.readAndDispatch())
            display.sleep();
    }
    originalImage.dispose();
    display.dispose();
}

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From source file:org.eclipse.swt.snippets.Snippet174.java

static void resize(Canvas canvas) {
    Rectangle rect = canvas.getClientArea();
    int width = rect.width;
    int height = Math.max(rect.height, 1);
    GL.glViewport(0, 0, width, height);/*from  w w  w .  j a  v  a 2s .  c  om*/
    GL.glMatrixMode(GL.GL_PROJECTION);
    GL.glLoadIdentity();
    float aspect = (float) width / (float) height;
    GLU.gluPerspective(45.0f, aspect, 0.5f, 400.0f);
    GL.glMatrixMode(GL.GL_MODELVIEW);
    GL.glLoadIdentity();
}

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From source file:FocusTraversal.java

private void init() {
    shell.setLayout(new RowLayout());

    Composite composite1 = new Composite(shell, SWT.BORDER);
    composite1.setLayout(new RowLayout());
    composite1.setBackground(display.getSystemColor(SWT.COLOR_WHITE));

    Button button1 = new Button(composite1, SWT.PUSH);
    button1.setText("Button1");

    List list = new List(composite1, SWT.MULTI | SWT.BORDER);
    list.setItems(new String[] { "Item-1", "Item-2", "Item-3" });

    Button radioButton1 = new Button(composite1, SWT.RADIO);
    radioButton1.setText("radio-1");
    Button radioButton2 = new Button(composite1, SWT.RADIO);
    radioButton2.setText("radio-2");

    Composite composite2 = new Composite(shell, SWT.BORDER);
    composite2.setLayout(new RowLayout());
    composite2.setBackground(display.getSystemColor(SWT.COLOR_GREEN));

    Button button2 = new Button(composite2, SWT.PUSH);
    button2.setText("Button2");

    final Canvas canvas = new Canvas(composite2, SWT.NULL);
    canvas.setSize(50, 50);//from ww  w  .  j a  va 2 s .  co m
    canvas.setBackground(display.getSystemColor(SWT.COLOR_YELLOW));

    Combo combo = new Combo(composite2, SWT.DROP_DOWN);
    combo.add("combo");
    combo.select(0);

    canvas.addKeyListener(new KeyListener() {
        public void keyPressed(KeyEvent e) {
            GC gc = new GC(canvas);
            // Erase background first. 
            Rectangle rect = canvas.getClientArea();
            gc.fillRectangle(rect.x, rect.y, rect.width, rect.height);

            Font font = new Font(display, "Arial", 32, SWT.BOLD);
            gc.setFont(font);

            gc.drawString("" + e.character, 15, 10);

            gc.dispose();
            font.dispose();
        }

        public void keyReleased(KeyEvent e) {
        }
    });

    canvas.addTraverseListener(new TraverseListener() {
        public void keyTraversed(TraverseEvent e) {
            if (e.detail == SWT.TRAVERSE_TAB_NEXT || e.detail == SWT.TRAVERSE_TAB_PREVIOUS)
                e.doit = true;
        }
    });

    composite1.setTabList(new Control[] { button1, list });
    composite2.setTabList(new Control[] { button2, canvas, combo });

    shell.setTabList(new Control[] { composite2, composite1 });
}

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From source file:org.eclipse.swt.examples.paint.PaintExample.java

/**
 * Creates the GUI.//w  w  w.  j av  a2 s  .c o m
 */
public void createGUI(Composite parent) {
    GridLayout gridLayout;
    GridData gridData;

    /*** Create principal GUI layout elements ***/
    Composite displayArea = new Composite(parent, SWT.NONE);
    gridLayout = new GridLayout();
    gridLayout.numColumns = 1;
    displayArea.setLayout(gridLayout);

    // Creating these elements here avoids the need to instantiate the GUI elements
    // in strict layout order.  The natural layout ordering is an artifact of using
    // SWT layouts, but unfortunately it is not the same order as that required to
    // instantiate all of the non-GUI application elements to satisfy referential
    // dependencies.  It is possible to reorder the initialization to some extent, but
    // this can be very tedious.

    // paint canvas
    final Canvas paintCanvas = new Canvas(displayArea,
            SWT.BORDER | SWT.V_SCROLL | SWT.H_SCROLL | SWT.NO_REDRAW_RESIZE | SWT.NO_BACKGROUND);
    gridData = new GridData(GridData.FILL_HORIZONTAL | GridData.FILL_VERTICAL);
    paintCanvas.setLayoutData(gridData);
    paintCanvas.setBackground(paintColorWhite);

    // color selector frame
    final Composite colorFrame = new Composite(displayArea, SWT.NONE);
    gridData = new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL);
    colorFrame.setLayoutData(gridData);

    // tool settings frame
    final Composite toolSettingsFrame = new Composite(displayArea, SWT.NONE);
    gridData = new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL);
    toolSettingsFrame.setLayoutData(gridData);

    // status text
    final Text statusText = new Text(displayArea, SWT.BORDER | SWT.SINGLE | SWT.READ_ONLY);
    gridData = new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL);
    statusText.setLayoutData(gridData);

    /*** Create the remaining application elements inside the principal GUI layout elements ***/
    // paintSurface
    paintSurface = new PaintSurface(paintCanvas, statusText, paintColorWhite);

    // finish initializing the tool data
    tools[Pencil_tool].data = new PencilTool(toolSettings, paintSurface);
    tools[Airbrush_tool].data = new AirbrushTool(toolSettings, paintSurface);
    tools[Line_tool].data = new LineTool(toolSettings, paintSurface);
    tools[PolyLine_tool].data = new PolyLineTool(toolSettings, paintSurface);
    tools[Rectangle_tool].data = new RectangleTool(toolSettings, paintSurface);
    tools[RoundedRectangle_tool].data = new RoundedRectangleTool(toolSettings, paintSurface);
    tools[Ellipse_tool].data = new EllipseTool(toolSettings, paintSurface);
    tools[Text_tool].data = new TextTool(toolSettings, paintSurface);

    // colorFrame
    gridLayout = new GridLayout();
    gridLayout.numColumns = 3;
    gridLayout.marginHeight = 0;
    gridLayout.marginWidth = 0;
    colorFrame.setLayout(gridLayout);

    // activeForegroundColorCanvas, activeBackgroundColorCanvas
    activeForegroundColorCanvas = new Canvas(colorFrame, SWT.BORDER);
    gridData = new GridData(GridData.HORIZONTAL_ALIGN_FILL);
    gridData.heightHint = 24;
    gridData.widthHint = 24;
    activeForegroundColorCanvas.setLayoutData(gridData);

    activeBackgroundColorCanvas = new Canvas(colorFrame, SWT.BORDER);
    gridData = new GridData(GridData.HORIZONTAL_ALIGN_FILL);
    gridData.heightHint = 24;
    gridData.widthHint = 24;
    activeBackgroundColorCanvas.setLayoutData(gridData);

    // paletteCanvas
    final Canvas paletteCanvas = new Canvas(colorFrame, SWT.BORDER | SWT.NO_BACKGROUND);
    gridData = new GridData(GridData.FILL_HORIZONTAL);
    gridData.heightHint = 24;
    paletteCanvas.setLayoutData(gridData);
    paletteCanvas.addListener(SWT.MouseDown, new Listener() {
        @Override
        public void handleEvent(Event e) {
            Rectangle bounds = paletteCanvas.getClientArea();
            Color color = getColorAt(bounds, e.x, e.y);

            if (e.button == 1)
                setForegroundColor(color);
            else
                setBackgroundColor(color);
        }

        private Color getColorAt(Rectangle bounds, int x, int y) {
            if (bounds.height <= 1 && bounds.width <= 1)
                return paintColorWhite;
            final int row = (y - bounds.y) * numPaletteRows / bounds.height;
            final int col = (x - bounds.x) * numPaletteCols / bounds.width;
            return paintColors[Math.min(Math.max(row * numPaletteCols + col, 0), paintColors.length - 1)];
        }
    });
    Listener refreshListener = e -> {
        if (e.gc == null)
            return;
        Rectangle bounds = paletteCanvas.getClientArea();
        for (int row = 0; row < numPaletteRows; ++row) {
            for (int col = 0; col < numPaletteCols; ++col) {
                final int x = bounds.width * col / numPaletteCols;
                final int y = bounds.height * row / numPaletteRows;
                final int width = Math.max(bounds.width * (col + 1) / numPaletteCols - x, 1);
                final int height = Math.max(bounds.height * (row + 1) / numPaletteRows - y, 1);
                e.gc.setBackground(paintColors[row * numPaletteCols + col]);
                e.gc.fillRectangle(bounds.x + x, bounds.y + y, width, height);
            }
        }
    };
    paletteCanvas.addListener(SWT.Resize, refreshListener);
    paletteCanvas.addListener(SWT.Paint, refreshListener);
    //paletteCanvas.redraw();

    // toolSettingsFrame
    gridLayout = new GridLayout();
    gridLayout.numColumns = 4;
    gridLayout.marginHeight = 0;
    gridLayout.marginWidth = 0;
    toolSettingsFrame.setLayout(gridLayout);

    Label label = new Label(toolSettingsFrame, SWT.NONE);
    label.setText(getResourceString("settings.AirbrushRadius.text"));

    final Scale airbrushRadiusScale = new Scale(toolSettingsFrame, SWT.HORIZONTAL);
    airbrushRadiusScale.setMinimum(5);
    airbrushRadiusScale.setMaximum(50);
    airbrushRadiusScale.setSelection(toolSettings.airbrushRadius);
    airbrushRadiusScale.setLayoutData(new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL));
    airbrushRadiusScale.addSelectionListener(widgetSelectedAdapter(e -> {
        toolSettings.airbrushRadius = airbrushRadiusScale.getSelection();
        updateToolSettings();
    }));

    label = new Label(toolSettingsFrame, SWT.NONE);
    label.setText(getResourceString("settings.AirbrushIntensity.text"));

    final Scale airbrushIntensityScale = new Scale(toolSettingsFrame, SWT.HORIZONTAL);
    airbrushIntensityScale.setMinimum(1);
    airbrushIntensityScale.setMaximum(100);
    airbrushIntensityScale.setSelection(toolSettings.airbrushIntensity);
    airbrushIntensityScale.setLayoutData(new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL));
    airbrushIntensityScale.addSelectionListener(widgetSelectedAdapter(e -> {
        toolSettings.airbrushIntensity = airbrushIntensityScale.getSelection();
        updateToolSettings();
    }));
}

---

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;//from  w  ww . ja  v a  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");
        }
    }));
}

---

From source file:PaintExample.java

/**
 * Creates the GUI.//from w w w. j ava  2s  . c  o  m
 */
public void createGUI(Composite parent) {
    GridLayout gridLayout;
    GridData gridData;

    /*** Create principal GUI layout elements ***/
    Composite displayArea = new Composite(parent, SWT.NONE);
    gridLayout = new GridLayout();
    gridLayout.numColumns = 1;
    displayArea.setLayout(gridLayout);

    // Creating these elements here avoids the need to instantiate the GUI elements
    // in strict layout order.  The natural layout ordering is an artifact of using
    // SWT layouts, but unfortunately it is not the same order as that required to
    // instantiate all of the non-GUI application elements to satisfy referential
    // dependencies.  It is possible to reorder the initialization to some extent, but
    // this can be very tedious.

    // paint canvas
    final Canvas paintCanvas = new Canvas(displayArea,
            SWT.BORDER | SWT.V_SCROLL | SWT.H_SCROLL | SWT.NO_REDRAW_RESIZE | SWT.NO_BACKGROUND);
    gridData = new GridData(GridData.FILL_HORIZONTAL | GridData.FILL_VERTICAL);
    paintCanvas.setLayoutData(gridData);
    paintCanvas.setBackground(paintColorWhite);

    // color selector frame
    final Composite colorFrame = new Composite(displayArea, SWT.NONE);
    gridData = new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL);
    colorFrame.setLayoutData(gridData);

    // tool settings frame
    final Composite toolSettingsFrame = new Composite(displayArea, SWT.NONE);
    gridData = new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL);
    toolSettingsFrame.setLayoutData(gridData);

    // status text
    final Text statusText = new Text(displayArea, SWT.BORDER | SWT.SINGLE | SWT.READ_ONLY);
    gridData = new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL);
    statusText.setLayoutData(gridData);

    /*** Create the remaining application elements inside the principal GUI layout elements ***/
    // paintSurface
    paintSurface = new PaintSurface(paintCanvas, statusText, paintColorWhite);

    // finish initializing the tool data
    tools[Pencil_tool].data = new PencilTool(toolSettings, paintSurface);
    tools[Airbrush_tool].data = new AirbrushTool(toolSettings, paintSurface);
    tools[Line_tool].data = new LineTool(toolSettings, paintSurface);
    tools[PolyLine_tool].data = new PolyLineTool(toolSettings, paintSurface);
    tools[Rectangle_tool].data = new RectangleTool(toolSettings, paintSurface);
    tools[RoundedRectangle_tool].data = new RoundedRectangleTool(toolSettings, paintSurface);
    tools[Ellipse_tool].data = new EllipseTool(toolSettings, paintSurface);
    tools[Text_tool].data = new TextTool(toolSettings, paintSurface);

    // colorFrame      
    gridLayout = new GridLayout();
    gridLayout.numColumns = 3;
    gridLayout.marginHeight = 0;
    gridLayout.marginWidth = 0;
    colorFrame.setLayout(gridLayout);

    // activeForegroundColorCanvas, activeBackgroundColorCanvas
    activeForegroundColorCanvas = new Canvas(colorFrame, SWT.BORDER);
    gridData = new GridData(GridData.HORIZONTAL_ALIGN_FILL);
    gridData.heightHint = 24;
    gridData.widthHint = 24;
    activeForegroundColorCanvas.setLayoutData(gridData);

    activeBackgroundColorCanvas = new Canvas(colorFrame, SWT.BORDER);
    gridData = new GridData(GridData.HORIZONTAL_ALIGN_FILL);
    gridData.heightHint = 24;
    gridData.widthHint = 24;
    activeBackgroundColorCanvas.setLayoutData(gridData);

    // paletteCanvas
    final Canvas paletteCanvas = new Canvas(colorFrame, SWT.BORDER | SWT.NO_BACKGROUND);
    gridData = new GridData(GridData.FILL_HORIZONTAL);
    gridData.heightHint = 24;
    paletteCanvas.setLayoutData(gridData);
    paletteCanvas.addListener(SWT.MouseDown, new Listener() {
        public void handleEvent(Event e) {
            Rectangle bounds = paletteCanvas.getClientArea();
            Color color = getColorAt(bounds, e.x, e.y);

            if (e.button == 1)
                setForegroundColor(color);
            else
                setBackgroundColor(color);
        }

        private Color getColorAt(Rectangle bounds, int x, int y) {
            if (bounds.height <= 1 && bounds.width <= 1)
                return paintColorWhite;
            final int row = (y - bounds.y) * numPaletteRows / bounds.height;
            final int col = (x - bounds.x) * numPaletteCols / bounds.width;
            return paintColors[Math.min(Math.max(row * numPaletteCols + col, 0), paintColors.length - 1)];
        }
    });
    Listener refreshListener = new Listener() {
        public void handleEvent(Event e) {
            if (e.gc == null)
                return;
            Rectangle bounds = paletteCanvas.getClientArea();
            for (int row = 0; row < numPaletteRows; ++row) {
                for (int col = 0; col < numPaletteCols; ++col) {
                    final int x = bounds.width * col / numPaletteCols;
                    final int y = bounds.height * row / numPaletteRows;
                    final int width = Math.max(bounds.width * (col + 1) / numPaletteCols - x, 1);
                    final int height = Math.max(bounds.height * (row + 1) / numPaletteRows - y, 1);
                    e.gc.setBackground(paintColors[row * numPaletteCols + col]);
                    e.gc.fillRectangle(bounds.x + x, bounds.y + y, width, height);
                }
            }
        }
    };
    paletteCanvas.addListener(SWT.Resize, refreshListener);
    paletteCanvas.addListener(SWT.Paint, refreshListener);
    //paletteCanvas.redraw();

    // toolSettingsFrame
    gridLayout = new GridLayout();
    gridLayout.numColumns = 4;
    gridLayout.marginHeight = 0;
    gridLayout.marginWidth = 0;
    toolSettingsFrame.setLayout(gridLayout);

    Label label = new Label(toolSettingsFrame, SWT.NONE);
    label.setText(getResourceString("settings.AirbrushRadius.text"));

    final Scale airbrushRadiusScale = new Scale(toolSettingsFrame, SWT.HORIZONTAL);
    airbrushRadiusScale.setMinimum(5);
    airbrushRadiusScale.setMaximum(50);
    airbrushRadiusScale.setSelection(toolSettings.airbrushRadius);
    airbrushRadiusScale.setLayoutData(new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL));
    airbrushRadiusScale.addSelectionListener(new SelectionAdapter() {
        public void widgetSelected(SelectionEvent e) {
            toolSettings.airbrushRadius = airbrushRadiusScale.getSelection();
            updateToolSettings();
        }
    });

    label = new Label(toolSettingsFrame, SWT.NONE);
    label.setText(getResourceString("settings.AirbrushIntensity.text"));

    final Scale airbrushIntensityScale = new Scale(toolSettingsFrame, SWT.HORIZONTAL);
    airbrushIntensityScale.setMinimum(1);
    airbrushIntensityScale.setMaximum(100);
    airbrushIntensityScale.setSelection(toolSettings.airbrushIntensity);
    airbrushIntensityScale.setLayoutData(new GridData(GridData.FILL_HORIZONTAL | GridData.VERTICAL_ALIGN_FILL));
    airbrushIntensityScale.addSelectionListener(new SelectionAdapter() {
        public void widgetSelected(SelectionEvent e) {
            toolSettings.airbrushIntensity = airbrushIntensityScale.getSelection();
            updateToolSettings();
        }
    });
}

---