package org.eclipse.swt.widgets; | |
/* | |
* (c) Copyright IBM Corp. 2000, 2001. | |
* All Rights Reserved | |
*/ | |
import org.eclipse.swt.internal.win32.*; | |
import org.eclipse.swt.*; | |
import org.eclipse.swt.graphics.*; | |
import org.eclipse.swt.events.*; | |
/** | |
* Instances of this class are selectable user interface | |
* objects that represent a range of positive, numeric values. | |
* <p> | |
* At any given moment, a given scroll bar will have a | |
* single <em>selection</em> that is considered to be its | |
* value, which is constrained to be within the range of | |
* values the scroll bar represents (that is, between its | |
* <em>minimum</em> and <em>maximum</em> values). | |
* </p><p> | |
* Typically, scroll bars will be made up of five areas: | |
* <ol> | |
* <li>an arrow button for decrementing the value</li> | |
* <li>a page decrement area for decrementing the value by a larger amount</li> | |
* <li>a <em>thumb</em> for modifying the value by mouse dragging</li> | |
* <li>a page increment area for incrementing the value by a larger amount</li> | |
* <li>an arrow button for incrementing the value</li> | |
* </ol> | |
* Based on their style, scroll bars are either <code>HORIZONTAL</code> | |
* (which have left and right facing buttons for incrementing and | |
* decrementing the value) or <code>VERTICAL</code> (which have | |
* up and down facing buttons for incrementing and decrementing | |
* the value). | |
* </p><p> | |
* On some platforms, the size of the scroll bar'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 scroll bar will not change. | |
* </p><p> | |
* Scroll bars are created by specifying either <code>H_SCROLL</code>, | |
* <code>V_SCROLL</code> or both when creating a <code>Scrollable</code>. | |
* They are accessed from the <code>Scrollable</code> using | |
* <code>getHorizontalBar</code> and <code>getVerticalBar</code>. | |
* </p><p> | |
* Note: Scroll bars are not Controls. On some platforms, scroll bars | |
* that appear as part of some standard controls such as a text or list | |
* have no operating system resources and are not children of the control. | |
* For this reason, scroll bars are treated specially. To create a control | |
* that looks like a scroll bar but has operating system resources, use | |
* <code>Slider</code>. | |
* </p> | |
* <dl> | |
* <dt><b>Styles:</b></dt> | |
* <dd>HORIZONTAL, VERTICAL</dd> | |
* <dt><b>Events:</b></dt> | |
* <dd>Selection</dd> | |
* </dl> | |
* <p> | |
* IMPORTANT: This class is <em>not</em> intended to be subclassed. | |
* | |
* @see Slider | |
* @see Scrollable | |
* @see Scrollable#getHorizontalBar | |
* @see Scrollable#getVerticalBar | |
*/ | |
public class ScrollBar extends Widget { | |
Scrollable parent; | |
int increment, pageIncrement; | |
/** | |
* Constructs a new instance of this class given its parent | |
* and a style value describing its behavior and appearance. | |
* <p> | |
* The style value is either one of the style constants defined in | |
* class <code>SWT</code> which is applicable to instances of this | |
* class, or must be built by <em>bitwise OR</em>'ing together | |
* (that is, using the <code>int</code> "|" operator) two or more | |
* of those <code>SWT</code> style constants. The class description | |
* for all SWT widget classes should include a comment which | |
* describes the style constants which are applicable to the class. | |
* </p> | |
* | |
* @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 <ul> | |
* <li>ERROR_NULL_ARGUMENT - if the parent is null</li> | |
* </ul> | |
* @exception SWTException <ul> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the parent</li> | |
* <li>ERROR_INVALID_SUBCLASS - if this class is not an allowed subclass</li> | |
* </ul> | |
* | |
* @see SWT | |
* @see Widget#checkSubclass | |
* @see Widget#getStyle | |
*/ | |
ScrollBar (Scrollable parent, int style) { | |
super (parent, checkStyle (style)); | |
this.parent = parent; | |
createWidget (); | |
} | |
/** | |
* Adds the listener to the collection of listeners who will | |
* be notified when the receiver's value changes, by sending | |
* it one of the messages defined in the <code>SelectionListener</code> | |
* interface. | |
* <p> | |
* When <code>widgetSelected</code> is called, the event object detail field contains one of the following values: | |
* <code>0</code> - for the end of a drag. | |
* <code>SWT.DRAG</code>. | |
* <code>SWT.HOME</code>. | |
* <code>SWT.END</code>. | |
* <code>SWT.ARROW_DOWN</code>. | |
* <code>SWT.ARROW_UP</code>. | |
* <code>SWT.PAGE_DOWN</code>. | |
* <code>SWT.PAGE_UP</code>. | |
* <code>widgetDefaultSelected</code> is not called. | |
* </p> | |
* | |
* @param listener the listener which should be notified | |
* | |
* @exception IllegalArgumentException <ul> | |
* <li>ERROR_NULL_ARGUMENT - if the listener is null</li> | |
* </ul> | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
* | |
* @see SelectionListener | |
* @see #removeSelectionListener | |
* @see SelectionEvent | |
*/ | |
public void addSelectionListener (SelectionListener listener) { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
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); | |
} | |
void createWidget () { | |
increment = 1; | |
pageIncrement = 10; | |
} | |
void destroyWidget () { | |
int hwnd = hwndScrollBar (), type = scrollBarType (); | |
if (OS.ShowScrollBar (hwnd, type, false)); | |
} | |
/* | |
* Not currently used. | |
*/ | |
Rectangle getBounds () { | |
RECT rect = new RECT (); | |
OS.GetClientRect (parent.handle, rect); | |
int x = 0, y = 0, width, height; | |
if ((style & SWT.HORIZONTAL) != 0) { | |
y = rect.bottom - rect.top; | |
width = rect.right - rect.left; | |
height = OS.GetSystemMetrics (OS.SM_CYHSCROLL); | |
} else { | |
x = rect.right - rect.left; | |
width = OS.GetSystemMetrics (OS.SM_CXVSCROLL); | |
height = rect.bottom - rect.top; | |
} | |
return new Rectangle (x, y, width, height); | |
} | |
public Display getDisplay () { | |
Scrollable parent = this.parent; | |
if (parent == null) error (SWT.ERROR_WIDGET_DISPOSED); | |
return parent.getDisplay (); | |
} | |
/** | |
* Returns <code>true</code> if the receiver is enabled, and | |
* <code>false</code> otherwise. A disabled control is typically | |
* not selectable from the user interface and draws with an | |
* inactive or "grayed" look. | |
* | |
* @return the enabled state | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public boolean getEnabled () { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
return (state & DISABLED) == 0; | |
} | |
/** | |
* 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 <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public int getIncrement () { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
return increment; | |
} | |
/** | |
* Returns the maximum value which the receiver will allow. | |
* | |
* @return the maximum | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public int getMaximum () { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
SCROLLINFO info = new SCROLLINFO (); | |
info.cbSize = SCROLLINFO.sizeof; | |
info.fMask = OS.SIF_RANGE; | |
int hwnd = hwndScrollBar (); | |
int type = scrollBarType (); | |
OS.GetScrollInfo (hwnd, type, info); | |
return info.nMax; | |
} | |
/** | |
* Returns the minimum value which the receiver will allow. | |
* | |
* @return the minimum | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public int getMinimum () { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
SCROLLINFO info = new SCROLLINFO (); | |
info.cbSize = SCROLLINFO.sizeof; | |
info.fMask = OS.SIF_RANGE; | |
int hwnd = hwndScrollBar (); | |
int type = scrollBarType (); | |
OS.GetScrollInfo (hwnd, type, info); | |
return info.nMin; | |
} | |
/** | |
* 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 <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public int getPageIncrement () { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
return pageIncrement; | |
} | |
/** | |
* Returns the receiver's parent, which must be scrollable. | |
* | |
* @return the receiver's parent | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public Scrollable getParent () { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
return parent; | |
} | |
/** | |
* Returns the single <em>selection</em> that is the receiver's value. | |
* | |
* @return the selection | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public int getSelection () { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
SCROLLINFO info = new SCROLLINFO (); | |
info.cbSize = SCROLLINFO.sizeof; | |
info.fMask = OS.SIF_POS; | |
int hwnd = hwndScrollBar (); | |
int type = scrollBarType (); | |
OS.GetScrollInfo (hwnd, type, info); | |
return info.nPos; | |
} | |
/** | |
* For horizontal scroll bars, returns the height of the | |
* instance, and for vertical scroll bars, returns the width | |
* of the instance. | |
* | |
* @return the scroll bar size | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public Point getSize () { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
RECT rect = new RECT (); | |
OS.GetClientRect (parent.handle, rect); | |
int width, height; | |
if ((style & SWT.HORIZONTAL) != 0) { | |
width = rect.right - rect.left; | |
height = OS.GetSystemMetrics (OS.SM_CYHSCROLL); | |
} else { | |
width = OS.GetSystemMetrics (OS.SM_CXVSCROLL); | |
height = rect.bottom - rect.top; | |
} | |
return new Point (width, height); | |
} | |
/** | |
* Answers the size of the receiver's thumb relative to the | |
* difference between its maximum and minimum values. | |
* | |
* @return the thumb value | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
* | |
* @see ScrollBar | |
*/ | |
public int getThumb () { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
SCROLLINFO info = new SCROLLINFO (); | |
info.cbSize = SCROLLINFO.sizeof; | |
info.fMask = OS.SIF_PAGE; | |
int hwnd = hwndScrollBar (); | |
int type = scrollBarType (); | |
OS.GetScrollInfo (hwnd, type, info); | |
if (info.nPage != 0) --info.nPage; | |
return info.nPage; | |
} | |
/** | |
* Returns <code>true</code> if the receiver is visible, and | |
* <code>false</code> otherwise. | |
* <p> | |
* If one of the receiver's ancestors is not visible or some | |
* other condition makes the receiver not visible, this method | |
* may still indicate that it is considered visible even though | |
* it may not actually be showing. | |
* </p> | |
* | |
* @return the receiver's visibility state | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public boolean getVisible () { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
return (state & HIDDEN) == 0; | |
} | |
int hwndScrollBar () { | |
return parent.handle; | |
} | |
/** | |
* Returns <code>true</code> if the receiver is enabled, and | |
* <code>false</code> otherwise. A disabled control is typically | |
* not selectable from the user interface and draws with an | |
* inactive or "grayed" look. | |
* <p> | |
* Note: Because of the strong connection between a scroll bar | |
* and the widget which contains it (its parent), a scroll bar | |
* will not indicate that it is enabled if its parent is not. | |
* </p> | |
* | |
* @return the receiver's enabled state | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public boolean isEnabled () { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
return getEnabled () && parent.isEnabled (); | |
} | |
/** | |
* Returns <code>true</code> if the receiver is visible, and | |
* <code>false</code> otherwise. | |
* <p> | |
* If one of the receiver's ancestors is not visible or some | |
* other condition makes the receiver not visible, this method | |
* may still indicate that it is considered visible even though | |
* it may not actually be showing. | |
* </p> | |
* | |
* @return the receiver's visibility state | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public boolean isVisible () { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
return getVisible () && parent.isVisible (); | |
} | |
void releaseChild () { | |
super.releaseChild (); | |
if (parent.horizontalBar == this) parent.horizontalBar = null; | |
if (parent.verticalBar == this) parent.verticalBar = null; | |
} | |
void releaseWidget () { | |
super.releaseWidget (); | |
parent = null; | |
} | |
/** | |
* Removes the listener from the collection of listeners who will | |
* be notified when the receiver's value changes. | |
* | |
* @param listener the listener which should no longer be notified | |
* | |
* @exception IllegalArgumentException <ul> | |
* <li>ERROR_NULL_ARGUMENT - if the listener is null</li> | |
* </ul> | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
* | |
* @see SelectionListener | |
* @see #addSelectionListener | |
*/ | |
public void removeSelectionListener (SelectionListener listener) { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
if (listener == null) error (SWT.ERROR_NULL_ARGUMENT); | |
if (eventTable == null) return; | |
eventTable.unhook (SWT.Selection, listener); | |
eventTable.unhook (SWT.DefaultSelection,listener); | |
} | |
int scrollBarType () { | |
if ((style & SWT.VERTICAL) != 0) return OS.SB_VERT; | |
/* | |
* This line is intentionally commented. There should | |
* only ever be HORIZONTAL and VERTICAL scroll bars. | |
* The commented code reminds us that this is the case | |
* and that the default style is HORIZONTAL. | |
*/ | |
// if ((style & SWT.HORIZONTAL) != 0) return OS.SB_HORZ; | |
return OS.SB_HORZ; | |
} | |
/** | |
* Enables the receiver if the argument is <code>true</code>, | |
* and disables it otherwise. A disabled control is typically | |
* not selectable from the user interface and draws with an | |
* inactive or "grayed" look. | |
* | |
* @param enabled the new enabled state | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public void setEnabled (boolean enabled) { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
int hwnd = hwndScrollBar (), type = scrollBarType (); | |
int flags = OS.ESB_DISABLE_BOTH; | |
if (enabled) flags = OS.ESB_ENABLE_BOTH; | |
OS.EnableScrollBar (hwnd, type, flags); | |
state &= ~DISABLED; | |
if (!enabled) state |= DISABLED; | |
} | |
/** | |
* 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 <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public void setIncrement (int value) { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
if (value < 1) return; | |
increment = value; | |
} | |
/** | |
* Sets the maximum value which the receiver will allow | |
* to be the argument which must be greater than or | |
* equal to zero. | |
* | |
* @param value the new maximum (must be zero or greater) | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public void setMaximum (int value) { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
if (value < 0) return; | |
SCROLLINFO info = new SCROLLINFO (); | |
info.cbSize = SCROLLINFO.sizeof; | |
int hwnd = hwndScrollBar (), type = scrollBarType (); | |
info.fMask = OS.SIF_RANGE | OS.SIF_DISABLENOSCROLL; | |
OS.GetScrollInfo (hwnd, type, info); | |
if (value - info.nMin - info.nPage < 1) return; | |
info.nMax = value; | |
OS.SetScrollInfo (hwnd, type, info, (state & DISABLED) == 0); | |
/* | |
* Bug in Windows. For some reason, when the widget | |
* is a standard scroll bar, and SetScrollInfo () is | |
* called with SIF_RANGE or SIF_PAGE, the widget is | |
* incorrectly made visible so that the next time the | |
* widget is resized (or another scroll bar operation | |
* is performed), the scroll bar draws. The fix is | |
* to hide the scroll bar (again) when already hidden. | |
*/ | |
if ((state & HIDDEN) != 0) { | |
OS.ShowScrollBar (hwnd, type, false); | |
} | |
/* | |
* Feature in Windows. Using SIF_DISABLENOSCROLL, | |
* SetScrollInfo () can change enabled and disabled | |
* state of the scroll bar causing a scroll bar that | |
* was disabled by the application to become enabled. | |
* The fix is to disable the scroll bar (again) when | |
* the application has disabled the scroll bar. | |
*/ | |
if ((state & DISABLED) != 0) { | |
OS.EnableScrollBar (hwnd, type, OS.ESB_DISABLE_BOTH); | |
} | |
} | |
/** | |
* Sets the minimum value which the receiver will allow | |
* to be the argument which must be greater than or | |
* equal to zero. | |
* | |
* @param value the new minimum (must be zero or greater) | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public void setMinimum (int value) { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
if (value < 0) return; | |
SCROLLINFO info = new SCROLLINFO (); | |
info.cbSize = SCROLLINFO.sizeof; | |
int hwnd = hwndScrollBar (), type = scrollBarType (); | |
info.fMask = OS.SIF_RANGE | OS.SIF_DISABLENOSCROLL; | |
OS.GetScrollInfo (hwnd, type, info); | |
if (info.nMax - value - info.nPage < 1) return; | |
info.nMin = value; | |
OS.SetScrollInfo (hwnd, type, info, true); | |
/* | |
* Bug in Windows. For some reason, when the widget | |
* is a standard scroll bar, and SetScrollInfo () is | |
* called with SIF_RANGE or SIF_PAGE, the widget is | |
* incorrectly made visible so that the next time the | |
* widget is resized (or another scroll bar operation | |
* is performed), the scroll bar draws. The fix is | |
* to hide the scroll bar (again) when already hidden. | |
*/ | |
if ((state & HIDDEN) != 0) { | |
OS.ShowScrollBar (hwnd, type, false); | |
} | |
/* | |
* Feature in Windows. Using SIF_DISABLENOSCROLL, | |
* SetScrollInfo () can change enabled and disabled | |
* state of the scroll bar causing a scroll bar that | |
* was disabled by the application to become enabled. | |
* The fix is to disable the scroll bar (again) when | |
* the application has disabled the scroll bar. | |
*/ | |
if ((state & DISABLED) != 0) { | |
OS.EnableScrollBar (hwnd, type, OS.ESB_DISABLE_BOTH); | |
} | |
} | |
/** | |
* 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. | |
* | |
* @return the page increment (must be greater than zero) | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public void setPageIncrement (int value) { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
if (value < 1) return; | |
pageIncrement = value; | |
} | |
/** | |
* Sets the single <em>selection</em> that 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 <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public void setSelection (int selection) { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
if (selection < 0) return; | |
SCROLLINFO info = new SCROLLINFO (); | |
info.cbSize = SCROLLINFO.sizeof; | |
int hwnd = hwndScrollBar (), type = scrollBarType (); | |
info.fMask = OS.SIF_POS; | |
info.nPos = selection; | |
OS.SetScrollInfo (hwnd, type, info, true); | |
} | |
/** | |
* Sets the size of the receiver's thumb relative to the | |
* difference between its maximum and minimum values to the | |
* argument which must be at least one. | |
* | |
* @param value the new thumb value (must be at least one) | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
* | |
* @see ScrollBar | |
*/ | |
public void setThumb (int value) { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
/* Position the thumb */ | |
if (value < 1) return; | |
SCROLLINFO info = new SCROLLINFO (); | |
info.cbSize = SCROLLINFO.sizeof; | |
int hwnd = hwndScrollBar (), type = scrollBarType (); | |
info.fMask = OS.SIF_PAGE | OS.SIF_RANGE | OS.SIF_DISABLENOSCROLL; | |
OS.GetScrollInfo (hwnd, type, info); | |
if (info.nMax - info.nMin - value < 0) return; | |
info.nPage = value; | |
if (info.nPage != 0) info.nPage++; | |
OS.SetScrollInfo (hwnd, type, info, true); | |
/* | |
* Bug in Windows. For some reason, when the widget | |
* is a standard scroll bar, and SetScrollInfo () is | |
* called with SIF_RANGE or SIF_PAGE, the widget is | |
* incorrectly made visible so that the next time the | |
* widget is resized (or another scroll bar operation | |
* is performed), the scroll bar draws. The fix is | |
* to hide the scroll bar (again) when already hidden. | |
*/ | |
if ((state & HIDDEN) != 0) { | |
OS.ShowScrollBar (hwnd, type, false); | |
} | |
/* | |
* Feature in Windows. Using SIF_DISABLENOSCROLL, | |
* SetScrollInfo () can change enabled and disabled | |
* state of the scroll bar causing a scroll bar that | |
* was disabled by the application to become enabled. | |
* The fix is to disable the scroll bar (again) when | |
* the application has disabled the scroll bar. | |
*/ | |
if ((state & DISABLED) != 0) { | |
OS.EnableScrollBar (hwnd, type, OS.ESB_DISABLE_BOTH); | |
} | |
} | |
/** | |
* Sets the receiver's selection, minimum value, maximum | |
* value, thumb, increment and page increment all at once. | |
* <p> | |
* Note: This is equivalent to setting the values individually | |
* using the appropriate methods, but may be implemented in a | |
* more efficient fashion on some platforms. | |
* </p> | |
* | |
* @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 <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public void setValues (int selection, int minimum, int maximum, int thumb, int increment, int pageIncrement) { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
if (selection < 0) return; | |
if (minimum < 0) return; | |
if (maximum < 0) return; | |
if (thumb < 1) return; | |
if (maximum - minimum - thumb < 0) return; | |
if (increment < 1) return; | |
if (pageIncrement < 1) return; | |
this.increment = increment; | |
this.pageIncrement = pageIncrement; | |
SCROLLINFO info = new SCROLLINFO (); | |
info.cbSize = SCROLLINFO.sizeof; | |
info.fMask = OS.SIF_POS | OS.SIF_PAGE | OS.SIF_RANGE | OS.SIF_DISABLENOSCROLL; | |
info.nPos = selection; | |
info.nMin = minimum; | |
info.nMax = maximum; | |
info.nPage = thumb; | |
if (info.nPage != 0) info.nPage++; | |
int hwnd = hwndScrollBar (), type = scrollBarType (); | |
OS.SetScrollInfo (hwnd, type, info, true); | |
/* | |
* Bug in Windows. For some reason, when the widget | |
* is a standard scroll bar, and SetScrollInfo () is | |
* called with SIF_RANGE or SIF_PAGE, the widget is | |
* incorrectly made visible so that the next time the | |
* widget is resized (or another scroll bar operation | |
* is performed), the scroll bar draws. The fix is | |
* to hide the scroll bar (again) when already hidden. | |
*/ | |
if ((state & HIDDEN) != 0) { | |
OS.ShowScrollBar (hwnd, type, false); | |
} | |
/* | |
* Feature in Windows. Using SIF_DISABLENOSCROLL, | |
* SetScrollInfo () can change enabled and disabled | |
* state of the scroll bar causing a scroll bar that | |
* was disabled by the application to become enabled. | |
* The fix is to disable the scroll bar (again) when | |
* the application has disabled the scroll bar. | |
*/ | |
if ((state & DISABLED) != 0) { | |
OS.EnableScrollBar (hwnd, type, OS.ESB_DISABLE_BOTH); | |
} | |
} | |
/** | |
* Marks the receiver as visible if the argument is <code>true</code>, | |
* and marks it invisible otherwise. | |
* <p> | |
* If one of the receiver's ancestors is not visible or some | |
* other condition makes the receiver not visible, marking | |
* it visible may not actually cause it to be displayed. | |
* </p> | |
* | |
* @param visible the new visibility state | |
* | |
* @exception SWTException <ul> | |
* <li>ERROR_WIDGET_DISPOSED - if the receiver has been disposed</li> | |
* <li>ERROR_THREAD_INVALID_ACCESS - if not called from the thread that created the receiver</li> | |
* </ul> | |
*/ | |
public void setVisible (boolean visible) { | |
if (!isValidThread ()) error (SWT.ERROR_THREAD_INVALID_ACCESS); | |
if (!isValidWidget ()) error (SWT.ERROR_WIDGET_DISPOSED); | |
int hwnd = hwndScrollBar (), type = scrollBarType (); | |
if (OS.ShowScrollBar (hwnd, type, visible)) { | |
/* | |
* Bug in Windows. For some reason, when the widget | |
* is a standard scroll bar, and SetScrollInfo () is | |
* called with SIF_RANGE or SIF_PAGE while the widget | |
* is not visible, the widget is incorrectly disabled | |
* even though the values for SIF_RANGE and SIF_PAGE, | |
* when set for a visible scroll bar would not disable | |
* the scroll bar. The fix is to enable the scroll bar | |
* when already enabled after showing the scroll bar. | |
*/ | |
if ((state & DISABLED) == 0) { | |
OS.EnableScrollBar (hwnd, type, OS.ESB_ENABLE_BOTH); | |
} | |
state &= ~HIDDEN; | |
if (!visible) state |= HIDDEN; | |
sendEvent (visible ? SWT.Show : SWT.Hide); | |
// widget could be disposed at this point | |
} | |
} | |
LRESULT wmScrollChild (int wParam, int lParam) { | |
/* Do nothing when scrolling is ending */ | |
int code = wParam & 0xFFFF; | |
if (code == OS.SB_ENDSCROLL) return null; | |
/* | |
* Send the event because WM_HSCROLL and | |
* WM_VSCROLL are sent from a modal message | |
* loop in Windows that is active when the | |
* user is scrolling. | |
*/ | |
Event event = new Event (); | |
switch (code) { | |
/* | |
* This line is intentionally commented. Do not set the detail | |
* field to DRAG to indicate that the dragging has ended when the | |
* scroll bar is finally positioned in SB_THUMBPOSITION. | |
*/ | |
// case OS.SB_THUMBPOSITION: break; | |
case OS.SB_THUMBTRACK: event.detail = SWT.DRAG; break; | |
case OS.SB_TOP: event.detail = SWT.HOME; break; | |
case OS.SB_BOTTOM: event.detail = SWT.END; break; | |
case OS.SB_LINEDOWN: event.detail = SWT.ARROW_DOWN; break; | |
case OS.SB_LINEUP: event.detail = SWT.ARROW_UP; break; | |
case OS.SB_PAGEDOWN: event.detail = SWT.PAGE_DOWN; break; | |
case OS.SB_PAGEUP: event.detail = SWT.PAGE_UP; break; | |
} | |
sendEvent (SWT.Selection, event); | |
// the widget could be destroyed at this point | |
return null; | |
} | |
} |