Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2012 IBM Corporation and others. * * This program and the accompanying materials * are made available under the terms of the Eclipse Public License 2.0 * which accompanies this distribution, and is available at * https://www.eclipse.org/legal/epl-2.0/ * * SPDX-License-Identifier: EPL-2.0 * * 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.*; /** * Instances of the receiver represent an unselectable * user interface object that is used to display progress, * typically in the form of a bar. * <dl> * <dt><b>Styles:</b></dt> * <dd>SMOOTH, HORIZONTAL, VERTICAL, INDETERMINATE</dd> * <dt><b>Events:</b></dt> * <dd>(none)</dd> * </dl> * <p> * Note: Only one of the styles HORIZONTAL and VERTICAL may be specified. * </p><p> * IMPORTANT: This class is <em>not</em> intended to be subclassed. * </p> * * @see <a href="http://www.eclipse.org/swt/snippets/#progressbar">ProgressBar snippets</a> * @see <a href="http://www.eclipse.org/swt/examples.php">SWT Example: ControlExample</a> * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a> * @noextend This class is not intended to be subclassed by clients. */ public class ProgressBar extends Control { static final int DELAY = 100; static final int TIMER_ID = 100; static final int MINIMUM_WIDTH = 100; static final long ProgressBarProc; static final TCHAR ProgressBarClass = new TCHAR(0, OS.PROGRESS_CLASS, true); static { WNDCLASS lpWndClass = new WNDCLASS(); OS.GetClassInfo(0, ProgressBarClass, lpWndClass); ProgressBarProc = lpWndClass.lpfnWndProc; /* * Feature in Windows. The progress bar window class * does not include CS_DBLCLKS. This means that these * controls will not get double click messages such as * WM_LBUTTONDBLCLK. The fix is to register a new * window class with CS_DBLCLKS. * * NOTE: Screen readers look for the exact class name * of the control in order to provide the correct kind * of assistance. Therefore, it is critical that the * new window class have the same name. It is possible * to register a local window class with the same name * as a global class. Since bits that affect the class * are being changed, it is possible that other native * code, other than SWT, could create a control with * this class name, and fail unexpectedly. */ lpWndClass.hInstance = OS.GetModuleHandle(null); lpWndClass.style &= ~OS.CS_GLOBALCLASS; lpWndClass.style |= OS.CS_DBLCLKS; OS.RegisterClass(ProgressBarClass, lpWndClass); } /** * 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 * lists the style constants that are applicable to the class. * Style bits are also inherited from superclasses. * </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#SMOOTH * @see SWT#HORIZONTAL * @see SWT#VERTICAL * @see SWT#INDETERMINATE * @see Widget#checkSubclass * @see Widget#getStyle */ public ProgressBar(Composite parent, int style) { super(parent, checkStyle(style)); } @Override long callWindowProc(long hwnd, int msg, long wParam, long lParam) { if (handle == 0) return 0; return OS.CallWindowProc(ProgressBarProc, hwnd, msg, wParam, lParam); } static int checkStyle(int style) { style |= SWT.NO_FOCUS; return checkBits(style, SWT.HORIZONTAL, SWT.VERTICAL, 0, 0, 0, 0); } @Override Point computeSizeInPixels(int wHint, int hHint, boolean changed) { checkWidget(); int border = getBorderWidthInPixels(); int width = border * 2, height = border * 2; if ((style & SWT.HORIZONTAL) != 0) { width += OS.GetSystemMetrics(OS.SM_CXHSCROLL) * 10; height += OS.GetSystemMetrics(OS.SM_CYHSCROLL); } else { width += OS.GetSystemMetrics(OS.SM_CXVSCROLL); height += OS.GetSystemMetrics(OS.SM_CYVSCROLL) * 10; } if (wHint != SWT.DEFAULT) width = wHint + (border * 2); if (hHint != SWT.DEFAULT) height = hHint + (border * 2); return new Point(width, height); } @Override void createHandle() { super.createHandle(); startTimer(); } @Override int defaultForeground() { return OS.GetSysColor(OS.COLOR_HIGHLIGHT); } /** * 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() { checkWidget(); return (int) OS.SendMessage(handle, OS.PBM_GETRANGE, 0, 0); } /** * 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() { checkWidget(); return (int) OS.SendMessage(handle, OS.PBM_GETRANGE, 1, 0); } /** * Returns the single 'selection' that is the receiver's position. * * @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() { checkWidget(); return (int) OS.SendMessage(handle, OS.PBM_GETPOS, 0, 0); } /** * Returns the state of the receiver. The value will be one of: * <ul> * <li>{@link SWT#NORMAL}</li> * <li>{@link SWT#ERROR}</li> * <li>{@link SWT#PAUSED}</li> * </ul> * * @return the 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> * * @since 3.4 */ public int getState() { checkWidget(); int state = (int) OS.SendMessage(handle, OS.PBM_GETSTATE, 0, 0); switch (state) { case OS.PBST_NORMAL: return SWT.NORMAL; case OS.PBST_ERROR: return SWT.ERROR; case OS.PBST_PAUSED: return SWT.PAUSED; } return SWT.NORMAL; } @Override void releaseWidget() { super.releaseWidget(); stopTimer(); } void startTimer() { if ((style & SWT.INDETERMINATE) != 0) { int bits = OS.GetWindowLong(handle, OS.GWL_STYLE); if ((bits & OS.PBS_MARQUEE) == 0) { OS.SetTimer(handle, TIMER_ID, DELAY, 0); } else { OS.SendMessage(handle, OS.PBM_SETMARQUEE, 1, DELAY); } } } void stopTimer() { if ((style & SWT.INDETERMINATE) != 0) { int bits = OS.GetWindowLong(handle, OS.GWL_STYLE); if ((bits & OS.PBS_MARQUEE) == 0) { OS.KillTimer(handle, TIMER_ID); } else { OS.SendMessage(handle, OS.PBM_SETMARQUEE, 0, 0); } } } @Override void setBackgroundPixel(int pixel) { if (pixel == -1) pixel = OS.CLR_DEFAULT; OS.SendMessage(handle, OS.PBM_SETBKCOLOR, 0, pixel); } @Override void setForegroundPixel(int pixel) { if (pixel == -1) pixel = OS.CLR_DEFAULT; OS.SendMessage(handle, OS.PBM_SETBARCOLOR, 0, pixel); } /** * Sets the maximum value that the receiver will allow. This new * value will be ignored if it is not greater than the receiver's current * minimum value. If the new maximum is applied then the receiver's * selection value will be adjusted if necessary to fall within its new range. * * @param value the new maximum, which must be greater than the current 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 void setMaximum(int value) { checkWidget(); int minimum = (int) OS.SendMessage(handle, OS.PBM_GETRANGE, 1, 0); if (0 <= minimum && minimum < value) { OS.SendMessage(handle, OS.PBM_SETRANGE32, minimum, value); } } /** * Sets the minimum value that the receiver will allow. This new * value will be ignored if it is negative or is not less than the receiver's * current maximum value. If the new minimum is applied then the receiver's * selection value will be adjusted if necessary to fall within its new range. * * @param value the new minimum, which must be nonnegative and less than the current 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 void setMinimum(int value) { checkWidget(); int maximum = (int) OS.SendMessage(handle, OS.PBM_GETRANGE, 0, 0); if (0 <= value && value < maximum) { OS.SendMessage(handle, OS.PBM_SETRANGE32, value, maximum); } } /** * Sets the single 'selection' that is the receiver's * position 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 value) { checkWidget(); OS.SendMessage(handle, OS.PBM_SETPOS, value, 0); /* * Bug in Vista. For some reason, when the progress bar is not in * a normal state, it shows the selection of previous call to * PBM_SETPOS. This is undocumented. The fix is to call PBM_SETPOS * a second time. */ long state = OS.SendMessage(handle, OS.PBM_GETSTATE, 0, 0); if (state != OS.PBST_NORMAL) { OS.SendMessage(handle, OS.PBM_SETPOS, value, 0); } } /** * Sets the state of the receiver. The state must be one of these values: * <ul> * <li>{@link SWT#NORMAL}</li> * <li>{@link SWT#ERROR}</li> * <li>{@link SWT#PAUSED}</li> * </ul> * <p> * Note: This operation is a hint and is not supported on * platforms that do not have this concept. * </p> * * @param state the new 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> * * @since 3.4 */ public void setState(int state) { checkWidget(); switch (state) { case SWT.NORMAL: OS.SendMessage(handle, OS.PBM_SETSTATE, OS.PBST_NORMAL, 0); break; case SWT.ERROR: OS.SendMessage(handle, OS.PBM_SETSTATE, OS.PBST_ERROR, 0); break; case SWT.PAUSED: OS.SendMessage(handle, OS.PBM_SETSTATE, OS.PBST_PAUSED, 0); break; } } @Override int widgetStyle() { int bits = super.widgetStyle(); if ((style & SWT.SMOOTH) != 0) bits |= OS.PBS_SMOOTH; if ((style & SWT.VERTICAL) != 0) bits |= OS.PBS_VERTICAL; if ((style & SWT.INDETERMINATE) != 0) bits |= OS.PBS_MARQUEE; return bits; } @Override TCHAR windowClass() { return ProgressBarClass; } @Override long windowProc() { return ProgressBarProc; } @Override LRESULT WM_GETDLGCODE(long wParam, long lParam) { LRESULT result = super.WM_GETDLGCODE(wParam, lParam); if (result != null) return result; /* * Feature in Windows. The progress bar does * not implement WM_GETDLGCODE. As a result, * a progress bar takes focus and takes part * in tab traversal. This behavior, while * unspecified, is unwanted. The fix is to * implement WM_GETDLGCODE to behave like a * STATIC control. */ return new LRESULT(OS.DLGC_STATIC); } @Override LRESULT WM_SIZE(long wParam, long lParam) { LRESULT result = super.WM_SIZE(wParam, lParam); if (result != null) return result; /* * Feature in Windows. When a progress bar with the style * PBS_MARQUEE becomes too small, the animation (currently * a small bar moving from right to left) does not have * enough space to draw. The result is that the progress * bar does not appear to be moving. The fix is to detect * this case, clear the PBS_MARQUEE style and emulate the * animation using PBM_STEPIT. * * NOTE: This only happens on Window XP. */ if ((style & SWT.INDETERMINATE) != 0) { if (!OS.IsAppThemed()) { forceResize(); RECT rect = new RECT(); OS.GetClientRect(handle, rect); int oldBits = OS.GetWindowLong(handle, OS.GWL_STYLE); int newBits = oldBits; if (rect.right - rect.left < MINIMUM_WIDTH) { newBits &= ~OS.PBS_MARQUEE; } else { newBits |= OS.PBS_MARQUEE; } if (newBits != oldBits) { stopTimer(); OS.SetWindowLong(handle, OS.GWL_STYLE, newBits); startTimer(); } } } return result; } @Override LRESULT WM_TIMER(long wParam, long lParam) { LRESULT result = super.WM_TIMER(wParam, lParam); if (result != null) return result; if ((style & SWT.INDETERMINATE) != 0) { int bits = OS.GetWindowLong(handle, OS.GWL_STYLE); if ((bits & OS.PBS_MARQUEE) == 0) { if (wParam == TIMER_ID) { OS.SendMessage(handle, OS.PBM_STEPIT, 0, 0); } } } return result; } }