/******************************************************************************* * 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.carbon.OS; 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 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); } int actionProc (int theControl, int partCode) { int result = super.actionProc (theControl, partCode); if (result == OS.noErr) return result; Event event = new Event (); int value = OS.GetControl32BitValue (handle); switch (partCode) { case OS.kControlUpButtonPart: value -= increment; event.detail = SWT.ARROW_UP; break; case OS.kControlPageUpPart: value -= pageIncrement; event.detail = SWT.PAGE_UP; break; case OS.kControlPageDownPart: value += pageIncrement; event.detail = SWT.PAGE_DOWN; break; case OS.kControlDownButtonPart: value += increment; event.detail = SWT.ARROW_DOWN; break; case OS.kControlIndicatorPart: dragging = true; event.detail = SWT.DRAG; break; default: return result; } OS.SetControl32BitValue (handle, value); sendEvent (SWT.Selection, event); return result; } public Point computeSize (int wHint, int hHint, boolean changed) { checkWidget(); int [] outMetric = new int [1]; OS.GetThemeMetric (OS.kThemeMetricScrollBarWidth, outMetric); int width = 0, height = 0; if ((style & SWT.HORIZONTAL) != 0) { height = outMetric [0]; width = height * 10; } else { width = outMetric [0]; height = width * 10; } if (wHint != SWT.DEFAULT) width = wHint; if (hHint != SWT.DEFAULT) height = hHint; return new Point (width, height); } void createHandle () { int actionProc = display.actionProc; int [] outControl = new int [1]; int window = OS.GetControlOwner (parent.handle); OS.CreateScrollBarControl (window, null, 0, 0, 90, 10, true, actionProc, outControl); if (outControl [0] == 0) error (SWT.ERROR_NO_HANDLES); handle = outControl [0]; } void drawBackground (int control, int context) { fillBackground (control, context, null); } /** * 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(); int maximum = OS.GetControl32BitMaximum (handle); int viewSize = OS.GetControlViewSize (handle); return maximum + viewSize; } /** * Returns the minimum value which the receiver will allow. * * @return the minimum * * @exception SWTException */ public int getMinimum () { checkWidget(); return OS.GetControl32BitMinimum (handle); } /** * 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(); return OS.GetControl32BitValue (handle); } /** * Returns the size of the receiver's thumb relative to the * difference between its maximum and minimum values. * * @return the thumb value * * @exception SWTException */ public int getThumb () { checkWidget(); return OS.GetControlViewSize (handle); } int kEventMouseDown (int nextHandler, int theEvent, int userData) { int status = super.kEventMouseDown (nextHandler, theEvent, userData); if (status == OS.noErr) return status; dragging = false; status = OS.CallNextEventHandler (nextHandler, theEvent); if (dragging) { Event event = new Event (); sendEvent (SWT.Selection, event); } dragging = false; return status; } /** * 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); } /** * 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; int minimum = OS.GetControl32BitMinimum (handle); if (value <= minimum) return; int viewSize = OS.GetControlViewSize (handle); if (value - minimum < viewSize) { viewSize = value - minimum; OS.SetControlViewSize (handle, viewSize); } OS.SetControl32BitMaximum (handle, value - viewSize); } /** * 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; int viewSize = OS.GetControlViewSize (handle); int maximum = OS.GetControl32BitMaximum (handle) + viewSize; if (value >= maximum) return; if (maximum - value < viewSize) { viewSize = maximum - value; OS.SetControl32BitMaximum (handle, maximum - viewSize); OS.SetControlViewSize (handle, viewSize); } OS.SetControl32BitMinimum (handle, value); } /** * 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(); OS.SetControl32BitValue (handle, value); } /** * Sets the size of the receiver's thumb relative to the * difference between its maximum and minimum values. 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; int minimum = OS.GetControl32BitMinimum (handle); int viewSize = OS.GetControlViewSize (handle); int maximum = OS.GetControl32BitMaximum (handle) + viewSize; value = Math.min (value, maximum - minimum); OS.SetControl32BitMaximum (handle, maximum - value); OS.SetControlViewSize (handle, 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); OS.SetControl32BitMinimum (handle, minimum); OS.SetControl32BitMaximum (handle, maximum - thumb); OS.SetControlViewSize (handle, thumb); OS.SetControl32BitValue (handle, selection); this.increment = increment; this.pageIncrement = pageIncrement; } }