/******************************************************************************* * Copyright (c) 2000, 2009 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.widgets; import org.eclipse.swt.internal.cocoa.*; import org.eclipse.swt.*; import org.eclipse.swt.events.*; import org.eclipse.swt.graphics.*; /** * Instances of this class are selectable user interface * objects that represent a range of positive, numeric values. *

* At any given moment, a given slider will have a * single 'selection' that is considered to be its * value, which is constrained to be within the range of * values the slider represents (that is, between its * minimum and maximum values). *

* Typically, sliders will be made up of five areas: *

    *
  1. an arrow button for decrementing the value
    2. *
  2. a page decrement area for decrementing the value by a larger amount
    3. *
  3. a thumb for modifying the value by mouse dragging
    4. *
  4. a page increment area for incrementing the value by a larger amount
    5. *
  5. an arrow button for incrementing the value
    6. *
* Based on their style, sliders are either HORIZONTAL * (which have a left facing button for decrementing the value and a * right facing button for incrementing it) or VERTICAL * (which have an upward facing button for decrementing the value * and a downward facing buttons for incrementing it). *

* On some platforms, the size of the slider's thumb can be * varied relative to the magnitude of the range of values it * represents (that is, relative to the difference between its * maximum and minimum values). Typically, this is used to * indicate some proportional value such as the ratio of the * visible area of a document to the total amount of space that * it would take to display it. SWT supports setting the thumb * size even if the underlying platform does not, but in this * case the appearance of the slider will not change. *

*
*
Styles:
*
HORIZONTAL, VERTICAL
*
Events:
*
Selection
*
*

* Note: Only one of the styles HORIZONTAL and VERTICAL may be specified. *

* IMPORTANT: This class is not intended to be subclassed. *

* * @see ScrollBar * @see Slider snippets * @see SWT Example: ControlExample * @see Sample code and further information * @noextend This class is not intended to be subclassed by clients. */ public class Slider extends Control { boolean dragging; int minimum, maximum, thumb; int increment = 1; int pageIncrement = 10; /** * Constructs a new instance of this class given its parent * and a style value describing its behavior and appearance. *

* The style value is either one of the style constants defined in * class SWT which is applicable to instances of this * class, or must be built by bitwise OR'ing together * (that is, using the int "|" operator) two or more * of those SWT style constants. The class description * lists the style constants that are applicable to the class. * Style bits are also inherited from superclasses. *

* * @param parent a composite control which will be the parent of the new instance (cannot be null) * @param style the style of control to construct * * @exception IllegalArgumentException * @exception SWTException * * @see SWT#HORIZONTAL * @see SWT#VERTICAL * @see Widget#checkSubclass * @see Widget#getStyle */ public Slider (Composite parent, int style) { super (parent, checkStyle (style)); } /** * Adds the listener to the collection of listeners who will * be notified when the user changes the receiver's value, by sending * it one of the messages defined in the SelectionListener * interface. *

* When widgetSelected is called, the event object detail field contains one of the following values: * SWT.NONE - for the end of a drag. * SWT.DRAG. * SWT.HOME. * SWT.END. * SWT.ARROW_DOWN. * SWT.ARROW_UP. * SWT.PAGE_DOWN. * SWT.PAGE_UP. * widgetDefaultSelected is not called. *

* * @param listener the listener which should be notified when the user changes the receiver's value * * @exception IllegalArgumentException * @exception SWTException * * @see SelectionListener * @see #removeSelectionListener * @see SelectionEvent */ public void addSelectionListener(SelectionListener listener) { checkWidget(); if (listener == null) error (SWT.ERROR_NULL_ARGUMENT); TypedListener typedListener = new TypedListener(listener); addListener(SWT.Selection,typedListener); addListener(SWT.DefaultSelection,typedListener); } static int checkStyle (int style) { return checkBits (style, SWT.HORIZONTAL, SWT.VERTICAL, 0, 0, 0, 0); } public Point computeSize (int wHint, int hHint, boolean changed) { checkWidget(); int width = 0, height = 0; if ((style & SWT.HORIZONTAL) != 0) { height = (int)NSScroller.scrollerWidthForControlSize(((NSScroller)view).controlSize()); width = height * 10; } else { width = (int)NSScroller.scrollerWidthForControlSize(((NSScroller)view).controlSize()); height = width * 10; } if (wHint != SWT.DEFAULT) width = wHint; if (hHint != SWT.DEFAULT) height = hHint; return new Point (width, height); } void createHandle () { NSScroller widget = (NSScroller)new SWTScroller().alloc(); NSRect rect = new NSRect(); if ((style & SWT.HORIZONTAL) != 0) { rect.width = 1; } else { rect.height = 1; } widget.initWithFrame(rect); widget.setEnabled(true); widget.setTarget(widget); widget.setAction(OS.sel_sendSelection); view = widget; updateBar(0, minimum, maximum, thumb); } void createWidget () { maximum = 100; thumb = 10; super.createWidget(); } NSFont defaultNSFont () { return display.scrollerFont; } void enableWidget(boolean enabled) { super.enableWidget(enabled); if (enabled) { int range = maximum - thumb - minimum; if (range <= 0) ((NSScroller)view).setEnabled(false); } }; /** * Returns the amount that the receiver's value will be * modified by when the up/down (or right/left) arrows * are pressed. * * @return the increment * * @exception SWTException */ public int getIncrement () { checkWidget(); return increment; } /** * Returns the maximum value which the receiver will allow. * * @return the maximum * * @exception SWTException */ public int getMaximum () { checkWidget(); return maximum; } /** * Returns the minimum value which the receiver will allow. * * @return the minimum * * @exception SWTException */ public int getMinimum () { checkWidget(); return minimum; } /** * Returns the amount that the receiver's value will be * modified by when the page increment/decrement areas * are selected. * * @return the page increment * * @exception SWTException */ public int getPageIncrement () { checkWidget(); return pageIncrement; } /** * Returns the 'selection', which is the receiver's value. * * @return the selection * * @exception SWTException */ public int getSelection () { checkWidget(); NSScroller widget = (NSScroller)view; double value = widget.doubleValue(); return (int)(0.5f + ((maximum - thumb - minimum) * value + minimum)); } /** * Returns the receiver's thumb value. * * @return the thumb value * * @exception SWTException */ public int getThumb () { checkWidget(); return thumb; } /** * Removes the listener from the collection of listeners who will * be notified when the user changes the receiver's value. * * @param listener the listener which should no longer be notified * * @exception IllegalArgumentException * @exception SWTException * * @see SelectionListener * @see #addSelectionListener */ public void removeSelectionListener(SelectionListener listener) { checkWidget(); if (listener == null) error (SWT.ERROR_NULL_ARGUMENT); if (eventTable == null) return; eventTable.unhook(SWT.Selection, listener); eventTable.unhook(SWT.DefaultSelection,listener); } void sendSelection () { Event event = new Event(); int hitPart = (int)/*64*/((NSScroller)view).hitPart(); int value = getSelection (); switch (hitPart) { case OS.NSScrollerDecrementLine: event.detail = SWT.ARROW_UP; value -= increment; break; case OS.NSScrollerDecrementPage: value -= pageIncrement; event.detail = SWT.PAGE_UP; break; case OS.NSScrollerIncrementLine: value += increment; event.detail = SWT.ARROW_DOWN; break; case OS.NSScrollerIncrementPage: value += pageIncrement; event.detail = SWT.PAGE_DOWN; break; case OS.NSScrollerKnob: event.detail = SWT.DRAG; break; } if (event.detail != SWT.DRAG) { setSelection(value); } sendSelectionEvent(SWT.Selection, event, true); } /** * Sets the amount that the receiver's value will be * modified by when the up/down (or right/left) arrows * are pressed to the argument, which must be at least * one. * * @param value the new increment (must be greater than zero) * * @exception SWTException */ public void setIncrement (int value) { checkWidget(); if (value < 1) return; increment = value; } /** * Sets the maximum. If this value is negative or less than or * equal to the minimum, the value is ignored. If necessary, first * the thumb and then the selection are adjusted to fit within the * new range. * * @param value the new maximum, which must be greater than the current minimum * * @exception SWTException */ public void setMaximum (int value) { checkWidget(); if (value < 0) return; if (value <= minimum) return; if (value - minimum < thumb) { thumb = value - minimum; } int selection = Math.max(minimum, Math.min (getSelection (), value - thumb)); this.maximum = value; updateBar(selection, minimum, value, thumb); } /** * Sets the minimum value. If this value is negative or greater * than or equal to the maximum, the value is ignored. If necessary, * first the thumb and then the selection are adjusted to fit within * the new range. * * @param value the new minimum * * @exception SWTException */ public void setMinimum (int value) { checkWidget(); if (value < 0) return; if (value >= maximum) return; if (maximum - value < thumb) { thumb = maximum - value; } int selection = Math.min(maximum - thumb, Math.max (getSelection (), value)); this.minimum = value; updateBar(selection, value, maximum, thumb); } /** * Sets the amount that the receiver's value will be * modified by when the page increment/decrement areas * are selected to the argument, which must be at least * one. * * @param value the page increment (must be greater than zero) * * @exception SWTException */ public void setPageIncrement (int value) { checkWidget(); if (value < 1) return; pageIncrement = value; } /** * Sets the 'selection', which is the receiver's * value, to the argument which must be greater than or equal * to zero. * * @param value the new selection (must be zero or greater) * * @exception SWTException */ public void setSelection (int value) { checkWidget(); updateBar(value, minimum, maximum, thumb); } void setSmallSize () { /* This code is intentionally comment */ // ((NSScroller)view).setControlSize (OS.NSSmallControlSize); } void updateBar (int selection, int minimum, int maximum, int thumb) { NSScroller widget = (NSScroller)view; selection = Math.max (minimum, Math.min (maximum - thumb, selection)); int range = maximum - thumb - minimum; float fraction = range <= 0 ? 1 : (float)(selection - minimum) / range; float knob = range <= 0 ? 1 : (float)thumb / (maximum - minimum); widget.setDoubleValue(fraction); widget.setKnobProportion(knob); widget.setEnabled (range > 0); } /** * Sets the thumb value. The thumb value should be used to represent * the size of the visual portion of the current range. This value is * usually the same as the page increment value. *

* This new value will be ignored if it is less than one, and will be * clamped if it exceeds the receiver's current range. *

* * @param value the new thumb value, which must be at least one and not * larger than the size of the current range * * @exception SWTException */ public void setThumb (int value) { checkWidget(); if (value < 1) return; value = Math.min (value, maximum - minimum); updateBar(getSelection(), minimum, maximum, value); this.thumb = value; } /** * Sets the receiver's selection, minimum value, maximum * value, thumb, increment and page increment all at once. *

* Note: This is similar to setting the values individually * using the appropriate methods, but may be implemented in a * more efficient fashion on some platforms. *

* * @param selection the new selection value * @param minimum the new minimum value * @param maximum the new maximum value * @param thumb the new thumb value * @param increment the new increment value * @param pageIncrement the new pageIncrement value * * @exception SWTException */ public void setValues (int selection, int minimum, int maximum, int thumb, int increment, int pageIncrement) { checkWidget(); if (minimum < 0) return; if (maximum < 0) return; if (thumb < 1) return; if (increment < 1) return; if (pageIncrement < 1) return; thumb = Math.min (thumb, maximum - minimum); this.thumb = thumb; this.maximum = maximum; this.minimum = minimum; this.increment = increment; this.pageIncrement = pageIncrement; updateBar(selection, minimum, maximum, thumb); } }