Work around SWT 4.13 - 4.18 Win32 DnD bug 567422

[simantics/platform.git] / bundles / org.eclipse.swt.win32.win32.x86_64 / src / org / eclipse / swt / custom / BusyIndicator.java

diff --git a/bundles/org.eclipse.swt.win32.win32.x86_64/src/org/eclipse/swt/custom/BusyIndicator.java b/bundles/org.eclipse.swt.win32.win32.x86_64/src/org/eclipse/swt/custom/BusyIndicator.java
new file mode 100644 (file)
index 0000000..c100fb7
--- /dev/null
+++ b/bundles/org.eclipse.swt.win32.win32.x86_64/src/org/eclipse/swt/custom/BusyIndicator.java
@@ -0,0 +1,95 @@
+/*******************************************************************************
+ * Copyright (c) 2000, 2011 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.custom;
+
+
+import org.eclipse.swt.*;
+import org.eclipse.swt.graphics.*;
+import org.eclipse.swt.widgets.*;
+
+/**
+ * Support for showing a Busy Cursor during a long running process.
+ *
+ * @see <a href="http://www.eclipse.org/swt/snippets/#busyindicator">BusyIndicator snippets</a>
+ * @see <a href="http://www.eclipse.org/swt/">Sample code and further information</a>
+ */
+public class BusyIndicator {
+
+       static int nextBusyId = 1;
+       static final String BUSYID_NAME = "SWT BusyIndicator"; //$NON-NLS-1$
+       static final String BUSY_CURSOR = "SWT BusyIndicator Cursor"; //$NON-NLS-1$
+
+       /**
+        * Runs the given <code>Runnable</code> while providing
+        * busy feedback using this busy indicator.
+        *
+        * @param display the display on which the busy feedback should be
+        *        displayed.  If the display is null, the Display for the current
+        *        thread will be used.  If there is no Display for the current thread,
+        *        the runnable code will be executed and no busy feedback will be displayed.
+        * @param runnable the runnable for which busy feedback is to be shown.
+        *        Must not be null.
+        *
+        * @exception IllegalArgumentException <ul>
+        *    <li>ERROR_NULL_ARGUMENT - if the runnable is null</li>
+        * </ul>
+        */
+
+       public static void showWhile(Display display, Runnable runnable) {
+               if (runnable == null)
+                       SWT.error(SWT.ERROR_NULL_ARGUMENT);
+               if (display == null) {
+                       display = Display.getCurrent();
+                       if (display == null) {
+                               runnable.run();
+                               return;
+                       }
+               }
+
+               Integer busyId = Integer.valueOf(nextBusyId);
+               nextBusyId++;
+               Cursor cursor = display.getSystemCursor(SWT.CURSOR_WAIT);
+               Shell[] shells = display.getShells();
+               for (Shell shell : shells) {
+                       Integer id = (Integer)shell.getData(BUSYID_NAME);
+                       if (id == null) {
+                               setCursorAndId(shell, cursor, busyId);
+                       }
+               }
+
+               try {
+                       runnable.run();
+               } finally {
+                       shells = display.getShells();
+                       for (Shell shell : shells) {
+                               Integer id = (Integer)shell.getData(BUSYID_NAME);
+                               if (id == busyId) {
+                                       setCursorAndId(shell, null, null);
+                               }
+                       }
+               }
+       }
+
+       /**
+        * Paranoia code to make sure we don't break UI because of one shell disposed, see bug 532632 comment 20
+        */
+       private static void setCursorAndId(Shell shell, Cursor cursor, Integer busyId) {
+               if (!shell.isDisposed()) {
+                       shell.setCursor(cursor);
+               }
+               if (!shell.isDisposed()) {
+                       shell.setData(BUSYID_NAME, busyId);
+               }
+       }
+}