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/*******************************************************************************
 * Copyright (c) 2000, 2013 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.win32.*;
import org.eclipse.swt.*;
import org.eclipse.swt.graphics.*;
import org.eclipse.swt.events.*;

/**
 * Instances of this class support the layout of selectable
 * expand bar items.
 * 

* The item children that may be added to instances of this class * must be of type ExpandItem. *

*

*
Styles:
*
V_SCROLL
*
Events:
*
Expand, Collapse
*
*

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

* * @see ExpandItem * @see ExpandEvent * @see ExpandListener * @see ExpandAdapter * @see ExpandBar snippets * @see SWT Example: ControlExample * @see Sample code and further information * * @since 3.2 * @noextend This class is not intended to be subclassed by clients. */ public class ExpandBar extends Composite { ExpandItem[] items; int itemCount; ExpandItem focusItem; int spacing = 4; int yCurrentScroll; int /*long*/ hFont; /** * 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#V_SCROLL * @see Widget#checkSubclass * @see Widget#getStyle */ public ExpandBar (Composite parent, int style) { super (parent, checkStyle (style)); } /** * Adds the listener to the collection of listeners who will * be notified when an item in the receiver is expanded or collapsed * by sending it one of the messages defined in the ExpandListener * interface. * * @param listener the listener which should 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 ExpandListener * @see #removeExpandListener */ public void addExpandListener (ExpandListener listener) { checkWidget (); if (listener == null) error (SWT.ERROR_NULL_ARGUMENT); TypedListener typedListener = new TypedListener (listener); addListener (SWT.Expand, typedListener); addListener (SWT.Collapse, typedListener); } int /*long*/ callWindowProc (int /*long*/ hwnd, int msg, int /*long*/ wParam, int /*long*/ lParam) { if (handle == 0) return 0; return OS.DefWindowProc (hwnd, msg, wParam, lParam); } protected void checkSubclass () { if (!isValidSubclass ()) error (SWT.ERROR_INVALID_SUBCLASS); } static int checkStyle (int style) { style &= ~SWT.H_SCROLL; return style | SWT.NO_BACKGROUND; } public Point computeSize (int wHint, int hHint, boolean changed) { checkWidget (); int height = 0, width = 0; if (wHint == SWT.DEFAULT || hHint == SWT.DEFAULT) { if (itemCount > 0) { int /*long*/ hDC = OS.GetDC (handle); int /*long*/ hTheme = 0; if (isAppThemed ()) { hTheme = display.hExplorerBarTheme (); } int /*long*/ hCurrentFont = 0, oldFont = 0; if (hTheme == 0) { if (hFont != 0) { hCurrentFont = hFont; } else { if (!OS.IsWinCE) { NONCLIENTMETRICS info = OS.IsUnicode ? (NONCLIENTMETRICS) new NONCLIENTMETRICSW () : new NONCLIENTMETRICSA (); info.cbSize = NONCLIENTMETRICS.sizeof; if (OS.SystemParametersInfo (OS.SPI_GETNONCLIENTMETRICS, 0, info, 0)) { LOGFONT logFont = OS.IsUnicode ? (LOGFONT) ((NONCLIENTMETRICSW)info).lfCaptionFont : ((NONCLIENTMETRICSA)info).lfCaptionFont; hCurrentFont = OS.CreateFontIndirect (logFont); } } } if (hCurrentFont != 0) { oldFont = OS.SelectObject (hDC, hCurrentFont); } } height += spacing; for (int i = 0; i < itemCount; i++) { ExpandItem item = items [i]; height += item.getHeaderHeight (); if (item.expanded) height += item.height; height += spacing; width = Math.max (width, item.getPreferredWidth (hTheme, hDC)); } if (hCurrentFont != 0) { OS.SelectObject (hDC, oldFont); if (hCurrentFont != hFont) OS.DeleteObject (hCurrentFont); } OS.ReleaseDC (handle, hDC); } } if (width == 0) width = DEFAULT_WIDTH; if (height == 0) height = DEFAULT_HEIGHT; if (wHint != SWT.DEFAULT) width = wHint; if (hHint != SWT.DEFAULT) height = hHint; Rectangle trim = computeTrim (0, 0, width, height); return new Point (trim.width, trim.height); } void createHandle () { super.createHandle (); state &= ~CANVAS; state |= TRACK_MOUSE; } void createItem (ExpandItem item, int style, int index) { if (!(0 <= index && index <= itemCount)) error (SWT.ERROR_INVALID_RANGE); if (itemCount == items.length) { ExpandItem [] newItems = new ExpandItem [itemCount + 4]; System.arraycopy (items, 0, newItems, 0, items.length); items = newItems; } System.arraycopy (items, index, items, index + 1, itemCount - index); items [index] = item; itemCount++; if (focusItem == null) focusItem = item; RECT rect = new RECT (); OS.GetWindowRect (handle, rect); item.width = Math.max (0, rect.right - rect.left - spacing * 2); layoutItems (index, true); } void createWidget () { super.createWidget (); items = new ExpandItem [4]; if (!isAppThemed ()) { backgroundMode = SWT.INHERIT_DEFAULT; } } int defaultBackground() { if (!isAppThemed ()) { return OS.GetSysColor (OS.COLOR_WINDOW); } return super.defaultBackground(); } void destroyItem (ExpandItem item) { int index = 0; while (index < itemCount) { if (items [index] == item) break; index++; } if (index == itemCount) return; if (item == focusItem) { int focusIndex = index > 0 ? index - 1 : 1; if (focusIndex < itemCount) { focusItem = items [focusIndex]; focusItem.redraw (true); } else { focusItem = null; } } System.arraycopy (items, index + 1, items, index, --itemCount - index); items [itemCount] = null; item.redraw (true); layoutItems (index, true); } void drawThemeBackground (int /*long*/ hDC, int /*long*/ hwnd, RECT rect) { RECT rect2 = new RECT (); OS.GetClientRect (handle, rect2); OS.MapWindowPoints (handle, hwnd, rect2, 2); OS.DrawThemeBackground (display.hExplorerBarTheme (), hDC, OS.EBP_NORMALGROUPBACKGROUND, 0, rect2, null); } void drawWidget (GC gc, RECT clipRect) { int /*long*/ hTheme = 0; if (isAppThemed ()) { hTheme = display.hExplorerBarTheme (); } if (hTheme != 0) { RECT rect = new RECT (); OS.GetClientRect (handle, rect); OS.DrawThemeBackground (hTheme, gc.handle, OS.EBP_HEADERBACKGROUND, 0, rect, clipRect); } else { drawBackground (gc.handle); } boolean drawFocus = false; if (handle == OS.GetFocus ()) { int uiState = (int)/*64*/OS.SendMessage (handle, OS.WM_QUERYUISTATE, 0, 0); drawFocus = (uiState & OS.UISF_HIDEFOCUS) == 0; } int /*long*/ hCurrentFont = 0, oldFont = 0; if (hTheme == 0) { if (hFont != 0) { hCurrentFont = hFont; } else { if (!OS.IsWinCE) { NONCLIENTMETRICS info = OS.IsUnicode ? (NONCLIENTMETRICS) new NONCLIENTMETRICSW () : new NONCLIENTMETRICSA (); info.cbSize = NONCLIENTMETRICS.sizeof; if (OS.SystemParametersInfo (OS.SPI_GETNONCLIENTMETRICS, 0, info, 0)) { LOGFONT logFont = OS.IsUnicode ? (LOGFONT) ((NONCLIENTMETRICSW)info).lfCaptionFont : ((NONCLIENTMETRICSA)info).lfCaptionFont; hCurrentFont = OS.CreateFontIndirect (logFont); } } } if (hCurrentFont != 0) { oldFont = OS.SelectObject (gc.handle, hCurrentFont); } if (foreground != -1) { OS.SetTextColor (gc.handle, foreground); } } for (int i = 0; i < itemCount; i++) { ExpandItem item = items[i]; item.drawItem (gc, hTheme, clipRect, item == focusItem && drawFocus); } if (hCurrentFont != 0) { OS.SelectObject (gc.handle, oldFont); if (hCurrentFont != hFont) OS.DeleteObject (hCurrentFont); } } Control findBackgroundControl () { Control control = super.findBackgroundControl (); if (!isAppThemed ()) { if (control == null) control = this; } return control; } Control findThemeControl () { return isAppThemed () ? this : super.findThemeControl (); } int getBandHeight () { if (hFont == 0) return ExpandItem.CHEVRON_SIZE; int /*long*/ hDC = OS.GetDC (handle); int /*long*/ oldHFont = OS.SelectObject (hDC, hFont); TEXTMETRIC lptm = OS.IsUnicode ? (TEXTMETRIC)new TEXTMETRICW() : new TEXTMETRICA(); OS.GetTextMetrics (hDC, lptm); OS.SelectObject (hDC, oldHFont); OS.ReleaseDC (handle, hDC); return Math.max (ExpandItem.CHEVRON_SIZE, lptm.tmHeight + 4); } /** * Returns the item at the given, zero-relative index in the * receiver. Throws an exception if the index is out of range. * * @param index the index of the item to return * @return the item at the given index * * @exception IllegalArgumentException
    *
  • ERROR_INVALID_RANGE - if the index is not between 0 and the number of elements in the list minus 1 (inclusive)
  • *
* @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 ExpandItem getItem (int index) { checkWidget (); if (!(0 <= index && index < itemCount)) error (SWT.ERROR_INVALID_RANGE); return items [index]; } /** * Returns the number of items contained in the receiver. * * @return the number of items * * @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 getItemCount () { checkWidget (); return itemCount; } /** * Returns an array of ExpandItems which are the items * in the receiver. *

* Note: This is not the actual structure used by the receiver * to maintain its list of items, so modifying the array will * not affect the receiver. *

* * @return the items in the receiver * * @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 ExpandItem [] getItems () { checkWidget (); ExpandItem [] result = new ExpandItem [itemCount]; System.arraycopy (items, 0, result, 0, itemCount); return result; } /** * Returns the receiver's spacing. * * @return the spacing * * @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 getSpacing () { checkWidget (); return spacing; } /** * Searches the receiver's list starting at the first item * (index 0) until an item is found that is equal to the * argument, and returns the index of that item. If no item * is found, returns -1. * * @param item the search item * @return the index of the item * * @exception IllegalArgumentException
    *
  • ERROR_NULL_ARGUMENT - if the item is null
  • *
  • ERROR_INVALID_ARGUMENT - if the item has been disposed
  • *
* @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 indexOf (ExpandItem item) { checkWidget (); if (item == null) error (SWT.ERROR_NULL_ARGUMENT); for (int i = 0; i < itemCount; i++) { if (items [i] == item) return i; } return -1; } boolean isAppThemed () { if (background != -1) return false; if (foreground != -1) return false; if (hFont != 0) return false; return OS.COMCTL32_MAJOR >= 6 && OS.IsAppThemed (); } void layoutItems (int index, boolean setScrollbar) { if (index < itemCount) { int y = spacing - yCurrentScroll; for (int i = 0; i < index; i++) { ExpandItem item = items [i]; if (item.expanded) y += item.height; y += item.getHeaderHeight () + spacing; } for (int i = index; i < itemCount; i++) { ExpandItem item = items [i]; item.setBounds (spacing, y, 0, 0, true, false); if (item.expanded) y += item.height; y += item.getHeaderHeight () + spacing; } } if (setScrollbar) setScrollbar (); } void releaseChildren (boolean destroy) { if (items != null) { for (int i=0; i *
  • 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 ExpandListener * @see #addExpandListener */ public void removeExpandListener (ExpandListener listener) { checkWidget (); if (listener == null) error (SWT.ERROR_NULL_ARGUMENT); if (eventTable == null) return; eventTable.unhook (SWT.Expand, listener); eventTable.unhook (SWT.Collapse, listener); } void reskinChildren (int flags) { if (items != null) { for (int i=0; i 0 && height > maxHeight) { yCurrentScroll = Math.max (0, yCurrentScroll + maxHeight - height); layoutItems (0, false); } maxHeight += yCurrentScroll; SCROLLINFO info = new SCROLLINFO (); info.cbSize = SCROLLINFO.sizeof; info.fMask = OS.SIF_RANGE | OS.SIF_PAGE | OS.SIF_POS; info.nMin = 0; info.nMax = maxHeight; info.nPage = height; info.nPos = Math.min (yCurrentScroll, info.nMax); if (info.nPage != 0) info.nPage++; OS.SetScrollInfo (handle, OS.SB_VERT, info, true); } /** * Sets the receiver's spacing. Spacing specifies the number of pixels allocated around * each item. * * @param spacing the spacing around each item * * @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 setSpacing (int spacing) { checkWidget (); if (spacing < 0) return; if (spacing == this.spacing) return; this.spacing = spacing; RECT rect = new RECT (); OS.GetClientRect (handle, rect); int width = Math.max (0, (rect.right - rect.left) - spacing * 2); for (int i = 0; i < itemCount; i++) { ExpandItem item = items[i]; if (item.width != width) item.setBounds (0, 0, width, item.height, false, true); } layoutItems (0, true); OS.InvalidateRect (handle, null, true); } boolean updateTextDirection(int textDirection) { if (super.updateTextDirection(textDirection)) { for (int i = 0, n = items.length; i < n; i++) { if (items[i] != null) { items[i].updateTextDirection(style & SWT.FLIP_TEXT_DIRECTION); } } return true; } return false; } void showItem (ExpandItem item) { Control control = item.control; if (control != null && !control.isDisposed ()) { control.setVisible (item.expanded); } item.redraw (true); int index = indexOf (item); layoutItems (index + 1, true); } void showFocus (boolean up) { RECT rect = new RECT(); OS.GetClientRect (handle, rect); int height = rect.bottom - rect.top; int updateY = 0; if (up) { if (focusItem.y < 0) { updateY = Math.min (yCurrentScroll, -focusItem.y); } } else { int itemHeight = focusItem.y + getBandHeight (); if (focusItem.expanded) { if (height >= getBandHeight () + focusItem.height) { itemHeight += focusItem.height; } } if (itemHeight > height) { updateY = height - itemHeight; } } if (updateY != 0) { yCurrentScroll = Math.max (0, yCurrentScroll - updateY); if ((style & SWT.V_SCROLL) != 0) { SCROLLINFO info = new SCROLLINFO (); info.cbSize = SCROLLINFO.sizeof; info.fMask = OS.SIF_POS; info.nPos = yCurrentScroll; OS.SetScrollInfo (handle, OS.SB_VERT, info, true); } OS.ScrollWindowEx (handle, 0, updateY, null, null, 0, null, OS.SW_SCROLLCHILDREN | OS.SW_INVALIDATE); for (int i = 0; i < itemCount; i++) { items [i].y += updateY; } } } TCHAR windowClass () { return display.windowClass; } int /*long*/ windowProc () { return display.windowProc; } LRESULT WM_KEYDOWN (int /*long*/ wParam, int /*long*/ lParam) { LRESULT result = super.WM_KEYDOWN (wParam, lParam); if (result != null) return result; if (focusItem == null) return result; switch ((int)/*64*/wParam) { case OS.VK_SPACE: case OS.VK_RETURN: Event event = new Event (); event.item = focusItem; sendEvent (focusItem.expanded ? SWT.Collapse : SWT.Expand, event); focusItem.expanded = !focusItem.expanded; showItem (focusItem); return LRESULT.ZERO; case OS.VK_UP: { int focusIndex = indexOf (focusItem); if (focusIndex > 0) { focusItem.redraw (true); focusItem = items [focusIndex - 1]; focusItem.redraw (true); showFocus (true); return LRESULT.ZERO; } break; } case OS.VK_DOWN: { int focusIndex = indexOf (focusItem); if (focusIndex < itemCount - 1) { focusItem.redraw (true); focusItem = items [focusIndex + 1]; focusItem.redraw (true); showFocus (false); return LRESULT.ZERO; } break; } } return result; } LRESULT WM_KILLFOCUS (int /*long*/ wParam, int /*long*/ lParam) { LRESULT result = super.WM_KILLFOCUS (wParam, lParam); if (focusItem != null) focusItem.redraw (true); return result; } LRESULT WM_LBUTTONDOWN (int /*long*/ wParam, int /*long*/ lParam) { LRESULT result = super.WM_LBUTTONDOWN (wParam, lParam); if (result == LRESULT.ZERO) return result; int x = OS.GET_X_LPARAM (lParam); int y = OS.GET_Y_LPARAM (lParam); for (int i = 0; i < itemCount; i++) { ExpandItem item = items[i]; boolean hover = item.isHover (x, y); if (hover && focusItem != item) { focusItem.redraw (true); focusItem = item; focusItem.redraw (true); forceFocus (); break; } } return result; } LRESULT WM_LBUTTONUP (int /*long*/ wParam, int /*long*/ lParam) { LRESULT result = super.WM_LBUTTONUP (wParam, lParam); if (result == LRESULT.ZERO) return result; if (focusItem == null) return result; int x = OS.GET_X_LPARAM (lParam); int y = OS.GET_Y_LPARAM (lParam); boolean hover = focusItem.isHover (x, y); if (hover) { Event event = new Event (); event.item = focusItem; sendEvent (focusItem.expanded ? SWT.Collapse : SWT.Expand, event); focusItem.expanded = !focusItem.expanded; showItem (focusItem); } return result; } LRESULT WM_MOUSELEAVE (int /*long*/ wParam, int /*long*/ lParam) { LRESULT result = super.WM_MOUSELEAVE (wParam, lParam); if (result != null) return result; for (int i = 0; i < itemCount; i++) { ExpandItem item = items [i]; if (item.hover) { item.hover = false; item.redraw (false); break; } } return result; } LRESULT WM_MOUSEMOVE (int /*long*/ wParam, int /*long*/ lParam) { LRESULT result = super.WM_MOUSEMOVE (wParam, lParam); if (result == LRESULT.ZERO) return result; int x = OS.GET_X_LPARAM (lParam); int y = OS.GET_Y_LPARAM (lParam); for (int i = 0; i < itemCount; i++) { ExpandItem item = items [i]; boolean hover = item.isHover (x, y); if (item.hover != hover) { item.hover = hover; item.redraw (false); } } return result; } LRESULT WM_MOUSEWHEEL (int /*long*/ wParam, int /*long*/ lParam) { return wmScrollWheel (true, wParam, lParam); } LRESULT WM_PAINT (int /*long*/ wParam, int /*long*/ lParam) { PAINTSTRUCT ps = new PAINTSTRUCT (); GCData data = new GCData (); data.ps = ps; data.hwnd = handle; GC gc = new_GC (data); if (gc != null) { int width = ps.right - ps.left; int height = ps.bottom - ps.top; if (width != 0 && height != 0) { RECT rect = new RECT (); OS.SetRect (rect, ps.left, ps.top, ps.right, ps.bottom); drawWidget (gc, rect); if (hooks (SWT.Paint) || filters (SWT.Paint)) { Event event = new Event (); event.gc = gc; event.x = rect.left; event.y = rect.top; event.width = width; event.height = height; sendEvent (SWT.Paint, event); event.gc = null; } } gc.dispose (); } return LRESULT.ZERO; } LRESULT WM_PRINTCLIENT (int /*long*/ wParam, int /*long*/ lParam) { LRESULT result = super.WM_PRINTCLIENT (wParam, lParam); RECT rect = new RECT (); OS.GetClientRect (handle, rect); GCData data = new GCData (); data.device = display; data.foreground = getForegroundPixel (); GC gc = GC.win32_new (wParam, data); drawWidget (gc, rect); gc.dispose (); return result; } LRESULT WM_SETCURSOR (int /*long*/ wParam, int /*long*/ lParam) { LRESULT result = super.WM_SETCURSOR (wParam, lParam); if (result != null) return result; int hitTest = (short) OS.LOWORD (lParam); if (hitTest == OS.HTCLIENT) { for (int i = 0; i < itemCount; i++) { ExpandItem item = items [i]; if (item.hover) { int /*long*/ hCursor = OS.LoadCursor (0, OS.IDC_HAND); OS.SetCursor (hCursor); return LRESULT.ONE; } } } return result; } LRESULT WM_SETFOCUS (int /*long*/ wParam, int /*long*/ lParam) { LRESULT result = super.WM_SETFOCUS (wParam, lParam); if (focusItem != null) focusItem.redraw (true); return result; } LRESULT WM_SIZE (int /*long*/ wParam, int /*long*/ lParam) { LRESULT result = super.WM_SIZE (wParam, lParam); RECT rect = new RECT (); OS.GetClientRect (handle, rect); int width = Math.max (0, (rect.right - rect.left) - spacing * 2); for (int i = 0; i < itemCount; i++) { ExpandItem item = items[i]; if (item.width != width) item.setBounds (0, 0, width, item.height, false, true); } setScrollbar (); OS.InvalidateRect (handle, null, true); return result; } LRESULT wmScroll (ScrollBar bar, boolean update, int /*long*/ hwnd, int msg, int /*long*/ wParam, int /*long*/ lParam) { LRESULT result = super.wmScroll (bar, true, hwnd, msg, wParam, lParam); SCROLLINFO info = new SCROLLINFO (); info.cbSize = SCROLLINFO.sizeof; info.fMask = OS.SIF_POS; OS.GetScrollInfo (handle, OS.SB_VERT, info); int updateY = yCurrentScroll - info.nPos; OS.ScrollWindowEx (handle, 0, updateY, null, null, 0, null, OS.SW_SCROLLCHILDREN | OS.SW_INVALIDATE); yCurrentScroll = info.nPos; if (updateY != 0) { for (int i = 0; i < itemCount; i++) { items [i].y += updateY; } } return result; } }




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