/*******************************************************************************
* Copyright (c) 2000, 2012 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.swt.examples.controlexample;
import org.eclipse.swt.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.widgets.*;
import org.eclipse.swt.events.*;
import org.eclipse.swt.layout.*;
class CanvasTab extends Tab {
static final int colors [] = {
SWT.COLOR_RED,
SWT.COLOR_GREEN,
SWT.COLOR_BLUE,
SWT.COLOR_MAGENTA,
SWT.COLOR_YELLOW,
SWT.COLOR_CYAN,
SWT.COLOR_DARK_RED,
SWT.COLOR_DARK_GREEN,
SWT.COLOR_DARK_BLUE,
SWT.COLOR_DARK_MAGENTA,
SWT.COLOR_DARK_YELLOW,
SWT.COLOR_DARK_CYAN
};
static final String canvasString = "Canvas"; //$NON-NLS-1$
/* Example widgets and groups that contain them */
Canvas canvas;
Group canvasGroup;
/* Style widgets added to the "Style" group */
Button horizontalButton, verticalButton, noBackgroundButton, noFocusButton,
noMergePaintsButton, noRedrawResizeButton, doubleBufferedButton;
/* Other widgets added to the "Other" group */
Button caretButton, fillDamageButton;
int paintCount;
int cx, cy;
int maxX, maxY;
/**
* Creates the Tab within a given instance of ControlExample.
*/
CanvasTab(ControlExample instance) {
super(instance);
}
/**
* Creates the "Other" group.
*/
void createOtherGroup () {
super.createOtherGroup ();
/* Create display controls specific to this example */
caretButton = new Button (otherGroup, SWT.CHECK);
caretButton.setText (ControlExample.getResourceString("Caret"));
fillDamageButton = new Button (otherGroup, SWT.CHECK);
fillDamageButton.setText (ControlExample.getResourceString("FillDamage"));
/* Add the listeners */
caretButton.addSelectionListener (new SelectionAdapter () {
public void widgetSelected (SelectionEvent event) {
setCaret ();
}
});
}
/**
* Creates the "Example" group.
*/
void createExampleGroup () {
super.createExampleGroup ();
/* Create a group for the canvas widget */
canvasGroup = new Group (exampleGroup, SWT.NONE);
canvasGroup.setLayout (new GridLayout ());
canvasGroup.setLayoutData (new GridData (SWT.FILL, SWT.FILL, true, true));
canvasGroup.setText ("Canvas");
}
/**
* Creates the "Example" widgets.
*/
void createExampleWidgets () {
/* Compute the widget style */
int style = getDefaultStyle();
if (horizontalButton.getSelection ()) style |= SWT.H_SCROLL;
if (verticalButton.getSelection ()) style |= SWT.V_SCROLL;
if (borderButton.getSelection ()) style |= SWT.BORDER;
if (noBackgroundButton.getSelection ()) style |= SWT.NO_BACKGROUND;
if (noFocusButton.getSelection ()) style |= SWT.NO_FOCUS;
if (noMergePaintsButton.getSelection ()) style |= SWT.NO_MERGE_PAINTS;
if (noRedrawResizeButton.getSelection ()) style |= SWT.NO_REDRAW_RESIZE;
if (doubleBufferedButton.getSelection ()) style |= SWT.DOUBLE_BUFFERED;
/* Create the example widgets */
paintCount = 0; cx = 0; cy = 0;
canvas = new Canvas (canvasGroup, style);
canvas.addPaintListener(new PaintListener () {
public void paintControl(PaintEvent e) {
paintCount++;
GC gc = e.gc;
if (fillDamageButton.getSelection ()) {
Color color = e.display.getSystemColor (colors [paintCount % colors.length]);
gc.setBackground(color);
gc.fillRectangle(e.x, e.y, e.width, e.height);
}
Point size = canvas.getSize ();
gc.drawArc(cx + 1, cy + 1, size.x - 2, size.y - 2, 0, 360);
gc.drawRectangle(cx + (size.x - 10) / 2, cy + (size.y - 10) / 2, 10, 10);
Point extent = gc.textExtent(canvasString);
gc.drawString(canvasString, cx + (size.x - extent.x) / 2, cy - extent.y + (size.y - 10) / 2, true);
}
});
canvas.addControlListener(new ControlAdapter() {
public void controlResized(ControlEvent event) {
Point size = canvas.getSize ();
maxX = size.x * 3 / 2; maxY = size.y * 3 / 2;
resizeScrollBars ();
}
});
ScrollBar bar = canvas.getHorizontalBar();
if (bar != null) {
bar.addSelectionListener(new SelectionAdapter() {
public void widgetSelected(SelectionEvent event) {
scrollHorizontal ((ScrollBar)event.widget);
}
});
}
bar = canvas.getVerticalBar();
if (bar != null) {
bar.addSelectionListener(new SelectionAdapter() {
public void widgetSelected(SelectionEvent event) {
scrollVertical ((ScrollBar)event.widget);
}
});
}
}
/**
* Creates the "Style" group.
*/
void createStyleGroup() {
super.createStyleGroup();
/* Create the extra widgets */
horizontalButton = new Button (styleGroup, SWT.CHECK);
horizontalButton.setText ("SWT.H_SCROLL");
horizontalButton.setSelection(true);
verticalButton = new Button (styleGroup, SWT.CHECK);
verticalButton.setText ("SWT.V_SCROLL");
verticalButton.setSelection(true);
borderButton = new Button (styleGroup, SWT.CHECK);
borderButton.setText ("SWT.BORDER");
noBackgroundButton = new Button (styleGroup, SWT.CHECK);
noBackgroundButton.setText ("SWT.NO_BACKGROUND");
noFocusButton = new Button (styleGroup, SWT.CHECK);
noFocusButton.setText ("SWT.NO_FOCUS");
noMergePaintsButton = new Button (styleGroup, SWT.CHECK);
noMergePaintsButton.setText ("SWT.NO_MERGE_PAINTS");
noRedrawResizeButton = new Button (styleGroup, SWT.CHECK);
noRedrawResizeButton.setText ("SWT.NO_REDRAW_RESIZE");
doubleBufferedButton = new Button (styleGroup, SWT.CHECK);
doubleBufferedButton.setText ("SWT.DOUBLE_BUFFERED");
}
/**
* Creates the tab folder page.
*
* @param tabFolder org.eclipse.swt.widgets.TabFolder
* @return the new page for the tab folder
*/
Composite createTabFolderPage (TabFolder tabFolder) {
super.createTabFolderPage (tabFolder);
/*
* Add a resize listener to the tabFolderPage so that
* if the user types into the example widget to change
* its preferred size, and then resizes the shell, we
* recalculate the preferred size correctly.
*/
tabFolderPage.addControlListener(new ControlAdapter() {
public void controlResized(ControlEvent e) {
setExampleWidgetSize ();
}
});
return tabFolderPage;
}
/**
* Gets the "Example" widget children.
*/
Control [] getExampleWidgets () {
return new Control [] {canvas};
}
/**
* Returns a list of set/get API method names (without the set/get prefix)
* that can be used to set/get values in the example control(s).
*/
String[] getMethodNames() {
return new String[] {"ToolTipText"};
}
/**
* Gets the text for the tab folder item.
*/
String getTabText () {
return "Canvas";
}
/**
* Resizes the maximum and thumb of both scrollbars.
*/
void resizeScrollBars () {
Rectangle clientArea = canvas.getClientArea();
ScrollBar bar = canvas.getHorizontalBar();
if (bar != null) {
bar.setMaximum(maxX);
bar.setThumb(clientArea.width);
bar.setPageIncrement(clientArea.width);
}
bar = canvas.getVerticalBar();
if (bar != null) {
bar.setMaximum(maxY);
bar.setThumb(clientArea.height);
bar.setPageIncrement(clientArea.height);
}
}
/**
* Scrolls the canvas horizontally.
*
* @param scrollBar
*/
void scrollHorizontal (ScrollBar scrollBar) {
Rectangle bounds = canvas.getClientArea();
int x = -scrollBar.getSelection();
if (x + maxX < bounds.width) {
x = bounds.width - maxX;
}
canvas.scroll(x, cy, cx, cy, maxX, maxY, false);
cx = x;
}
/**
* Scrolls the canvas vertically.
*
* @param scrollBar
*/
void scrollVertical (ScrollBar scrollBar) {
Rectangle bounds = canvas.getClientArea();
int y = -scrollBar.getSelection();
if (y + maxY < bounds.height) {
y = bounds.height - maxY;
}
canvas.scroll(cx, y, cx, cy, maxX, maxY, false);
cy = y;
}
/**
* Sets or clears the caret in the "Example" widget.
*/
void setCaret () {
Caret oldCaret = canvas.getCaret ();
if (caretButton.getSelection ()) {
Caret newCaret = new Caret(canvas, SWT.NONE);
Font font = canvas.getFont();
newCaret.setFont(font);
GC gc = new GC(canvas);
gc.setFont(font);
newCaret.setBounds(1, 1, 1, gc.getFontMetrics().getHeight());
gc.dispose();
canvas.setCaret (newCaret);
canvas.setFocus();
} else {
canvas.setCaret (null);
}
if (oldCaret != null) oldCaret.dispose ();
}
/**
* Sets the state of the "Example" widgets.
*/
void setExampleWidgetState () {
super.setExampleWidgetState ();
horizontalButton.setSelection ((canvas.getStyle () & SWT.H_SCROLL) != 0);
verticalButton.setSelection ((canvas.getStyle () & SWT.V_SCROLL) != 0);
borderButton.setSelection ((canvas.getStyle () & SWT.BORDER) != 0);
noBackgroundButton.setSelection ((canvas.getStyle () & SWT.NO_BACKGROUND) != 0);
noFocusButton.setSelection ((canvas.getStyle () & SWT.NO_FOCUS) != 0);
noMergePaintsButton.setSelection ((canvas.getStyle () & SWT.NO_MERGE_PAINTS) != 0);
noRedrawResizeButton.setSelection ((canvas.getStyle () & SWT.NO_REDRAW_RESIZE) != 0);
doubleBufferedButton.setSelection ((canvas.getStyle () & SWT.DOUBLE_BUFFERED) != 0);
if (!instance.startup) setCaret ();
}
}