org.eclipse.swt.widgets.Slider Maven / Gradle / Ivy
/*******************************************************************************
* Copyright (c) 2008, 2015 Innoopract Informationssysteme GmbH 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:
* Innoopract Informationssysteme GmbH - initial API and implementation
* EclipseSource - ongoing development
******************************************************************************/
package org.eclipse.swt.widgets;
import org.eclipse.rap.rwt.internal.lifecycle.WidgetLCA;
import org.eclipse.rap.rwt.theme.BoxDimensions;
import org.eclipse.swt.SWT;
import org.eclipse.swt.SWTException;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.internal.widgets.sliderkit.SliderLCA;
/**
* 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:
*
* - an arrow button for decrementing the value
* - a page decrement area for decrementing the value by a larger amount
* - a thumb for modifying the value by mouse dragging
* - a page increment area for incrementing the value by a larger amount
* - an arrow button for incrementing the value
*
* 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
* @since 1.2
*/
public class Slider extends Control {
private final Point PREFERRED_SIZE = new Point( 170, 16 );
private int increment;
private int maximum;
private int minimum;
private int pageIncrement;
private int selection;
private int thumb;
/**
* 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
* - ERROR_NULL_ARGUMENT - if the parent is null
*
* @exception SWTException
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent
* - ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass
*
*
* @see SWT#HORIZONTAL
* @see SWT#VERTICAL
* @see Widget#checkSubclass
* @see Widget#getStyle
*/
public Slider( Composite parent, int style ) {
super( parent, checkStyle (style) );
increment = 1;
maximum = 100;
minimum = 0;
pageIncrement = 10;
selection = 0;
thumb = 10;
}
/**
* 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
* - ERROR_NULL_ARGUMENT - if the listener is null
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*
* @see SelectionListener
* @see #removeSelectionListener
* @see SelectionEvent
*/
public void addSelectionListener( SelectionListener listener ) {
checkWidget();
if( listener == null ) {
SWT.error( SWT.ERROR_NULL_ARGUMENT );
}
TypedListener typedListener = new TypedListener( listener );
addListener( SWT.Selection, typedListener );
addListener( SWT.DefaultSelection, typedListener );
}
/**
* 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
* - ERROR_NULL_ARGUMENT - if the listener is null
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*
* @see SelectionListener
* @see #addSelectionListener
*/
public void removeSelectionListener( SelectionListener listener ) {
checkWidget();
if( listener == null ) {
SWT.error( SWT.ERROR_NULL_ARGUMENT );
}
removeListener( SWT.Selection, listener );
removeListener( SWT.DefaultSelection, listener );
}
static int checkStyle( int style ) {
return checkBits( style, SWT.HORIZONTAL, SWT.VERTICAL, 0, 0, 0, 0 );
}
@Override
public Point computeSize( int wHint, int hHint, boolean changed ) {
checkWidget();
int width, height;
if( ( style & SWT.HORIZONTAL ) != 0 ) {
width = PREFERRED_SIZE.x;
height = PREFERRED_SIZE.y;
} else {
width = PREFERRED_SIZE.y;
height = PREFERRED_SIZE.x;
}
if( wHint != SWT.DEFAULT ) {
width = wHint;
}
if( hHint != SWT.DEFAULT ) {
height = hHint;
}
BoxDimensions border = getBorder();
width += border.left + border.right;
height += border.top + border.bottom;
return new Point( width, height );
}
@Override
void createWidget() {
super.createWidget();
increment = 1;
pageIncrement = 10;
maximum = 100;
thumb = 10;
}
/**
* 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
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public int getIncrement() {
checkWidget();
return increment;
}
/**
* Returns the maximum value which the receiver will allow.
*
* @return the maximum
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public int getMaximum() {
checkWidget();
return maximum;
}
/**
* Returns the minimum value which the receiver will allow.
*
* @return the minimum
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
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
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public int getPageIncrement() {
checkWidget();
return pageIncrement;
}
/**
* Returns the 'selection', which is the receiver's value.
*
* @return the selection
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public int getSelection() {
checkWidget();
return selection;
}
/**
* Returns the size of the receiver's thumb relative to the
* difference between its maximum and minimum values.
*
* @return the thumb value
*
* @exception SWTException
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public int getThumb() {
checkWidget();
return thumb;
}
/**
* 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
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setIncrement( int value ) {
checkWidget();
if( value >= 1 && value <= maximum - minimum ) {
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
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setMaximum( int value ) {
checkWidget();
if( 0 <= minimum && minimum < value ) {
maximum = value;
if( selection > maximum - thumb ) {
selection = maximum - thumb;
}
}
if( thumb >= maximum - minimum ) {
thumb = maximum - minimum;
selection = minimum;
}
}
/**
* 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
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setMinimum( int value ) {
checkWidget();
if( 0 <= value && value < maximum ) {
minimum = value;
if( selection < minimum ) {
selection = minimum;
}
}
if( thumb >= maximum - minimum ) {
thumb = maximum - minimum;
selection = minimum;
}
}
/**
* 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
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setPageIncrement( int value ) {
checkWidget();
if( value >= 1 && value <= maximum - minimum ) {
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
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setSelection( int value ) {
checkWidget();
if( value < minimum ) {
selection = minimum;
} else if ( value > maximum - thumb ) {
selection = maximum - thumb;
} else {
selection = 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
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setThumb( int value ) {
checkWidget();
if( value >= 1 ) {
thumb = value;
}
if( value >= maximum - minimum ) {
thumb = maximum - minimum;
selection = minimum;
}
}
/**
* 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
* - ERROR_WIDGET_DISPOSED - if the receiver has been disposed
* - ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver
*
*/
public void setValues( int selection,
int minimum,
int maximum,
int thumb,
int increment,
int pageIncrement )
{
checkWidget();
if( selection >= minimum && selection <= maximum ) {
this.selection = selection;
}
if( 0 <= minimum && minimum < maximum ) {
this.minimum = minimum;
if( selection < minimum ) {
this.selection = minimum;
}
}
if( 0 <= minimum && minimum < maximum ) {
this.maximum = maximum;
if( selection > maximum - thumb ) {
this.selection = maximum - thumb;
}
}
if( thumb >= 1 ) {
this.thumb = thumb;
}
if( increment >= 1 && increment <= ( maximum - minimum ) ) {
this.increment = increment;
}
if( pageIncrement >= 1 && pageIncrement <= ( maximum - minimum ) ) {
this.pageIncrement = pageIncrement;
}
if( thumb >= maximum - minimum ) {
this.thumb = maximum - minimum;
this.selection = minimum;
}
}
@Override
@SuppressWarnings( "unchecked" )
public T getAdapter( Class adapter ) {
if( adapter == WidgetLCA.class ) {
return ( T )SliderLCA.INSTANCE;
}
return super.getAdapter( adapter );
}
@Override
boolean isTabGroup() {
return true;
}
}
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