Community
Participate
Working Groups
Build Identifier: 3.6.1 When using MAT with a screen reader (i.e. JAWS), icons are read as "Graphic XXXX". In tables, the whole row is read with no indication of the meaning of the column contents. In Trees, only the content of the first column is read. Reproducible: Always Steps to Reproduce: 1. Start Memory Analyzer on Windows with JAWS 2. Open Histogram view, listen to JAWS read the rows. 3. Open Dominator Tree view, listen to JAWS read the items.
Created attachment 192401 [details] Patch enabling JAWS to read graphics and table/tree items better.
The attached patch contains a partial fix to the reported issues: 1) Modifications to MemoryAnalyzerPlugin.java to maintain descriptive text for Images obtained via MemoryAnalyzerPlugin.java. Currently this text is derived from the file name for the Image, but should be obtained from an NLS-enabled message file. 2) A new class AccessibleCompositeAdapter which allows an AccessibleListener to be added to any Eclipse SWT Table or Tree to return an accessible name to the screen reader with descriptive text for any Images, and column headings describing the content. 3) Addition of the above Accessible decoration to several of the most important tables and views in the MAT UI. TODO 1) The descriptions for the Images need to be created in an NLS enabled properties file, and loaded according to the language. 2) More bug fixes, as some graphics in the UI are still not read correctly , and some views are not read appropriately.
I've applied this to my workspace and I get table rows being read out twice, once with the graphic label and once without. I'll investigate.
(In reply to comment #3) > I've applied this to my workspace and I get table rows being read out twice, > once with the graphic label and once without. I'll investigate. Yes this is how JAWS seems to work with ListView windows. I was not able to find a way to prevent JAWS from reading out the default content of each row in a table, so what happens now is that you get the customized text, then the original. If anyone can tell me how to use the SWT Accessibility APIs in order to achieve a better result I will be more than grateful. It works better with Tree views (Windows TreeViews), in which case JAWS reads out just the customized content for each row. These are issues which need to be raised both with the Eclipse SWT developers (to provide documentation for how the Accessibility APIs should be used by application developers, and by the accessibility clients), and with Freedom Scientific.
New patch, includes mechanism to NLS enable the text which is read out by a screen reader to describe icons in the UI. In order to NLS enable the text read out for an icon, the text needs to be held in a properties file, so that it can be translated. This implies a separate property for each icon file. It would be tedious, error prone, and result in excessive code to use a hard-coded key for each icon file. Instead, the property key for an icon label is generated from it's path relative to its parent /icons directory. The descriptive text for each icon is also generated automatically by an offline utility (main() method in MemoryAnalyzerPlugin), which scans the MAT icons directories and generates an "iconlabels.properties" file which is then used at runtime to retrieve the readable icon descriptions (labels) and is translatable. At runtime, when an icon description is needed, the key is generated from the icon file's path, and then the label is retrieved from the relevant NLS enabled properties file. The new patch is based on the current repository code version as of today's date, and therefore includes and supersedes the previous patch which has not yet been applied to the code base. The previous version of the patch should be ignored.
Created attachment 193433 [details] Revised fix for this bug, includes NLS support for icon labels. Described in previous comment. Previous patch is now obsolete.
I'm using JAWS 12. I found this link: http://www.eclipse.org/swt/faq.php#tableheaderswithJAWS This is a much more flexible way of controlling whether the column headers are read. Therefore, I don't think we should add the column names ourselves. There is also a Graphic Labeler option, which should convert a Graphic 252 into a name, but I don't know how we could preset these.
Running Memory Analyzer under the Eclipse debugger gives this exception: Thread [main] (Suspended (exception NoClassDefFoundError)) ClassLoader.defineClassImpl(String, byte[], int, int, Object) line: not available [native method] DefaultClassLoader(ClassLoader).defineClass(String, byte[], int, int, ProtectionDomain) line: 275 DefaultClassLoader.defineClass(String, byte[], ClasspathEntry, BundleEntry) line: 188 ClasspathManager.defineClass(String, byte[], ClasspathEntry, BundleEntry, ClassLoadingStatsHook[]) line: 580 ClasspathManager.findClassImpl(String, ClasspathEntry, ClassLoadingStatsHook[]) line: 550 ClasspathManager.findLocalClassImpl(String, ClassLoadingStatsHook[]) line: 481 ClasspathManager.findLocalClass_LockClassLoader(String, ClassLoadingStatsHook[]) line: 469 ClasspathManager.findLocalClass(String) line: 449 DefaultClassLoader.findLocalClass(String) line: 216 BundleLoader.findLocalClass(String) line: 393 BundleLoader.findClassInternal(String, boolean, ClassLoader) line: 469 BundleLoader.findClass(String, boolean) line: 422 BundleLoader.findClass(String) line: 410 DefaultClassLoader.loadClass(String, boolean) line: 107 DefaultClassLoader(ClassLoader).loadClass(String) line: 619 Class<T>.forNameImpl(String, boolean, ClassLoader) line: not available [native method] Class<T>.forName(String, boolean, ClassLoader) line: 172 ResourceBundle.handleGetBundle(String, String, boolean, ClassLoader) line: 468 ResourceBundle.handleGetBundle(String, String, boolean, ClassLoader) line: 523 ResourceBundle.handleGetBundle(String, String, boolean, ClassLoader) line: 523 ResourceBundle.getBundleImpl(String, Locale, ClassLoader) line: 362 ResourceBundle.getBundle(String) line: 104 IconLabels.<clinit>() line: 23 J9VMInternals.initializeImpl(Class) line: not available [native method] J9VMInternals.initialize(Class) line: 200 MemoryAnalyserPlugin.getIconString(String) line: 290 MemoryAnalyserPlugin.getPluginImageDescriptor(String) line: 200 MemoryAnalyserPlugin.getImageDescriptor(String) line: 184 InspectorView.createSyncAction() line: 436 InspectorView.createPartControl(Composite) line: 367 ViewReference.createPartHelper() line: 375 ViewReference.createPart() line: 229 ViewReference(WorkbenchPartReference).getPart(boolean) line: 595 ViewPane(PartPane).setVisible(boolean) line: 313 ViewPane.setVisible(boolean) line: 529 PresentablePart.setVisible(boolean) line: 180 PresentablePartFolder.select(IPresentablePart) line: 270 LeftToRightTabOrder.select(IPresentablePart) line: 65 TabbedStackPresentation.selectPart(IPresentablePart) line: 473 ViewStack(PartStack).refreshPresentationSelection() line: 1254 ViewStack(PartStack).createControl(Composite, StackPresentation) line: 666 ViewStack(PartStack).createControl(Composite) line: 574 ViewSashContainer(PartSashContainer).createControl(Composite) line: 568 PerspectiveHelper.activate(Composite) line: 272 Perspective.onActivate() line: 981 WorkbenchPage.onActivate() line: 2632 WorkbenchWindow$27.run() line: 2986 BusyIndicator.showWhile(Display, Runnable) line: 70 WorkbenchWindow.setActivePage(IWorkbenchPage) line: 2967 WorkbenchWindow$21.runWithException() line: 2284 WorkbenchWindow$21(StartupThreading$StartupRunnable).run() line: 31 RunnableLock.run() line: 35 UISynchronizer(Synchronizer).runAsyncMessages(boolean) line: 134 Display.runAsyncMessages(boolean) line: 4041 Display.readAndDispatch() line: 3660 ApplicationWorkbenchAdvisor(WorkbenchAdvisor).openWindows() line: 803 Workbench$31.runWithException() line: 1566 Workbench$31(StartupThreading$StartupRunnable).run() line: 31 UISynchronizer(Synchronizer).syncExec(Runnable) line: 179 UISynchronizer.syncExec(Runnable) line: 150 Display.syncExec(Runnable) line: 4584 StartupThreading.runWithoutExceptions(StartupThreading$StartupRunnable) line: 94 Workbench.init() line: 1561 Workbench.runUI() line: 2556 Workbench.access$4(Workbench) line: 2427 Workbench$7.run() line: 670 Realm.runWithDefault(Realm, Runnable) line: 332 Workbench.createAndRunWorkbench(Display, WorkbenchAdvisor) line: 663 PlatformUI.createAndRunWorkbench(Display, WorkbenchAdvisor) line: 149 Application.start(IApplicationContext) line: 52 EclipseAppHandle.run(Object) line: 196 EclipseAppLauncher.runApplication(Object) line: 110 EclipseAppLauncher.start(Object) line: 79 EclipseStarter.run(Object) line: 369 EclipseStarter.run(String[], Runnable) line: 179 NativeMethodAccessorImpl.invoke0(Method, Object, Object[]) line: not available [native method] NativeMethodAccessorImpl.invoke(Object, Object[]) line: 48 DelegatingMethodAccessorImpl.invoke(Object, Object[]) line: 25 Method.invoke(Object, Object...) line: 600 Main.invokeFramework(String[], URL[]) line: 619 Main.basicRun(String[]) line: 574 Main.run(String[]) line: 1407 Main.main(String[]) line: 1383 The line causing it is: private static final String BUNDLE_NAME = "org.eclipse.mat.ui.iconlabels"; //$NON-NLS-1$ private static final ResourceBundle RESOURCE_BUNDLE = ResourceBundle.getBundle(BUNDLE_NAME); Is this expected? I don't like to see exception thrown as part of normal behaviour as it makes debugging of problems harder.
Bug 115947 suggests using display.findWidget(composite, e.childID); for Trees Also see: give accessible names to a tree and its tree items http://dev.eclipse.org/viewcvs/viewvc.cgi/org.eclipse.swt.snippets/src/org/eclipse/swt/snippets/Snippet291.java?view=co
With JAWS 12 I can read a whole tree row using ctrl-shift-right arrow without this patch
Yes, this is better. Thanks. One odd thing about using this mechanism is that once the "Customize ListView (Headers)" dialog has been used for a given ListView which has column headers, JAWS 12 appears to stop reading the graphics altogether, and it does not seem to be possible to recover them even by reversing the applied customization. This doesn't happen if the ListView does not have column headers, eg the Inspector view. Therefore if one wants anything to be read for the graphics in a ListView, which seems desirable, this will need to be done by another mechanism. Regarding the Graphic Labeler, I could not get this to work in MAT. An error dialog is displayed stating that "The JAWS cursor is NOT positioned on a graphic". It also does not seem to be possible to preset the contents, confirming the comment mentioned below. (In reply to comment #7) > I'm using JAWS 12. > I found this link: http://www.eclipse.org/swt/faq.php#tableheaderswithJAWS > This is a much more flexible way of controlling whether the column headers are > read. > Therefore, I don't think we should add the column names ourselves. > > There is also a Graphic Labeler option, which should convert a Graphic 252 into > a name, but I don't know > how we could preset these.
The Exception appears to be inherent in the implementation of ResourceBundle.getBundle(). Because of the trial-and-error search mechanism for the most specific (class or property) resource bundle matching the base name & locale, the mechanism appears to rely on throwing & catching Exceptions. This is highly unfortunate as it appears to be the only place where internal exceptions are used on the mainline path of MAT. An alternative would be to implement a custom ResourceBundle loader which avoided throwing Exceptions internally, or not to attempt to label the graphics at all. (In reply to comment #8) > Running Memory Analyzer under the Eclipse debugger gives this exception: > > Thread [main] (Suspended (exception NoClassDefFoundError)) > ClassLoader.defineClassImpl(String, byte[], int, int, Object) line: not > available [native method] > DefaultClassLoader(ClassLoader).defineClass(String, byte[], int, int, > ProtectionDomain) line: 275 > DefaultClassLoader.defineClass(String, byte[], ClasspathEntry, BundleEntry) > line: 188 > ClasspathManager.defineClass(String, byte[], ClasspathEntry, BundleEntry, > ClassLoadingStatsHook[]) line: 580 > ClasspathManager.findClassImpl(String, ClasspathEntry, > ClassLoadingStatsHook[]) line: 550 > ClasspathManager.findLocalClassImpl(String, ClassLoadingStatsHook[]) line: > 481 > ClasspathManager.findLocalClass_LockClassLoader(String, > ClassLoadingStatsHook[]) line: 469 > ClasspathManager.findLocalClass(String) line: 449 > DefaultClassLoader.findLocalClass(String) line: 216 > BundleLoader.findLocalClass(String) line: 393 > BundleLoader.findClassInternal(String, boolean, ClassLoader) line: 469 > BundleLoader.findClass(String, boolean) line: 422 > BundleLoader.findClass(String) line: 410 > DefaultClassLoader.loadClass(String, boolean) line: 107 > DefaultClassLoader(ClassLoader).loadClass(String) line: 619 > Class<T>.forNameImpl(String, boolean, ClassLoader) line: not available > [native method] > Class<T>.forName(String, boolean, ClassLoader) line: 172 > ResourceBundle.handleGetBundle(String, String, boolean, ClassLoader) line: > 468 > ResourceBundle.handleGetBundle(String, String, boolean, ClassLoader) line: > 523 > ResourceBundle.handleGetBundle(String, String, boolean, ClassLoader) line: > 523 > ResourceBundle.getBundleImpl(String, Locale, ClassLoader) line: 362 > ResourceBundle.getBundle(String) line: 104 > IconLabels.<clinit>() line: 23 > J9VMInternals.initializeImpl(Class) line: not available [native method] > J9VMInternals.initialize(Class) line: 200 > MemoryAnalyserPlugin.getIconString(String) line: 290 > MemoryAnalyserPlugin.getPluginImageDescriptor(String) line: 200 > MemoryAnalyserPlugin.getImageDescriptor(String) line: 184 > InspectorView.createSyncAction() line: 436 > InspectorView.createPartControl(Composite) line: 367 > ViewReference.createPartHelper() line: 375 > ViewReference.createPart() line: 229 > ViewReference(WorkbenchPartReference).getPart(boolean) line: 595 > ViewPane(PartPane).setVisible(boolean) line: 313 > ViewPane.setVisible(boolean) line: 529 > PresentablePart.setVisible(boolean) line: 180 > PresentablePartFolder.select(IPresentablePart) line: 270 > LeftToRightTabOrder.select(IPresentablePart) line: 65 > TabbedStackPresentation.selectPart(IPresentablePart) line: 473 > ViewStack(PartStack).refreshPresentationSelection() line: 1254 > ViewStack(PartStack).createControl(Composite, StackPresentation) line: 666 > ViewStack(PartStack).createControl(Composite) line: 574 > ViewSashContainer(PartSashContainer).createControl(Composite) line: 568 > PerspectiveHelper.activate(Composite) line: 272 > Perspective.onActivate() line: 981 > WorkbenchPage.onActivate() line: 2632 > WorkbenchWindow$27.run() line: 2986 > BusyIndicator.showWhile(Display, Runnable) line: 70 > WorkbenchWindow.setActivePage(IWorkbenchPage) line: 2967 > WorkbenchWindow$21.runWithException() line: 2284 > WorkbenchWindow$21(StartupThreading$StartupRunnable).run() line: 31 > RunnableLock.run() line: 35 > UISynchronizer(Synchronizer).runAsyncMessages(boolean) line: 134 > Display.runAsyncMessages(boolean) line: 4041 > Display.readAndDispatch() line: 3660 > ApplicationWorkbenchAdvisor(WorkbenchAdvisor).openWindows() line: 803 > Workbench$31.runWithException() line: 1566 > Workbench$31(StartupThreading$StartupRunnable).run() line: 31 > UISynchronizer(Synchronizer).syncExec(Runnable) line: 179 > UISynchronizer.syncExec(Runnable) line: 150 > Display.syncExec(Runnable) line: 4584 > StartupThreading.runWithoutExceptions(StartupThreading$StartupRunnable) > line: 94 > Workbench.init() line: 1561 > Workbench.runUI() line: 2556 > Workbench.access$4(Workbench) line: 2427 > Workbench$7.run() line: 670 > Realm.runWithDefault(Realm, Runnable) line: 332 > Workbench.createAndRunWorkbench(Display, WorkbenchAdvisor) line: 663 > PlatformUI.createAndRunWorkbench(Display, WorkbenchAdvisor) line: 149 > Application.start(IApplicationContext) line: 52 > EclipseAppHandle.run(Object) line: 196 > EclipseAppLauncher.runApplication(Object) line: 110 > EclipseAppLauncher.start(Object) line: 79 > EclipseStarter.run(Object) line: 369 > EclipseStarter.run(String[], Runnable) line: 179 > NativeMethodAccessorImpl.invoke0(Method, Object, Object[]) line: not > available [native method] > NativeMethodAccessorImpl.invoke(Object, Object[]) line: 48 > DelegatingMethodAccessorImpl.invoke(Object, Object[]) line: 25 > Method.invoke(Object, Object...) line: 600 > Main.invokeFramework(String[], URL[]) line: 619 > Main.basicRun(String[]) line: 574 > Main.run(String[]) line: 1407 > Main.main(String[]) line: 1383 > > The line causing it is: > private static final String BUNDLE_NAME = "org.eclipse.mat.ui.iconlabels"; > //$NON-NLS-1$ > private static final ResourceBundle RESOURCE_BUNDLE = > ResourceBundle.getBundle(BUNDLE_NAME); > > Is this expected? I don't like to see exception thrown as part of normal > behaviour as it makes debugging of problems harder.
Yes, this could be an alternative. It's not clear whether it's an improvement on the implementation in the patch which uses getItem() for the same purpose, and seems to be working satisfactorily. (In reply to comment #9) > Bug 115947 suggests using display.findWidget(composite, e.childID); for Trees > > Also see: give accessible names to a tree and its tree items > http://dev.eclipse.org/viewcvs/viewvc.cgi/org.eclipse.swt.snippets/src/org/eclipse/swt/snippets/Snippet291.java?view=co
Thanks for pointing this out. It does read the whole row, but without column headers and without the graphics. There doesn't seem to be the equivalent of "Customize ListView" which works for TreeViews. (In reply to comment #10) > With JAWS 12 I can read a whole tree row using ctrl-shift-right arrow without > this patch
Proposal for changes to the fix, for further comment: ===================================================== 1) Remove the customized reading of ListView rows, except for the graphic label, so that "Customize ListView" can be used for the row content & column headers. Headers will still be read for empty cells, which was overridden in the original patch, however this seems acceptable. 2) Investigate whether there is a viable alternative to using ResourceBundle.getBundle() which does not rely on throwing & catching Exceptions internally, or implement one. Raise a bug against ResourceBundle to correct this problem. So with the above changes, the following aspects of the patch would (largely) remain: 1) The current mechanism for generating labels for the MAT graphics, and for reading them out in JAWS, for both ListView & TreeView. 2) The customized TreeView row reading which includes the column headers when a row is read out.
(In reply to comment #12) > The Exception appears to be inherent in the implementation of > ResourceBundle.getBundle(). Because of the trial-and-error search mechanism for > the most specific (class or property) resource bundle matching the base name & > locale, the mechanism appears to rely on throwing & catching Exceptions. > This is highly unfortunate as it appears to be the only place where internal > exceptions are used on the mainline path of MAT. An alternative would be to > implement a custom ResourceBundle loader which avoided throwing Exceptions > internally, or not to attempt to label the graphics at all. > > (In reply to comment #8) > > Running Memory Analyzer under the Eclipse debugger gives this exception: > > > > Thread [main] (Suspended (exception NoClassDefFoundError)) > > ClassLoader.defineClassImpl(String, byte[], int, int, Object) line: not > > available [native method] > > private static final ResourceBundle RESOURCE_BUNDLE = > > ResourceBundle.getBundle(BUNDLE_NAME); > > > > Is this expected? I don't like to see exception thrown as part of normal > > behaviour as it makes debugging of problems harder. Strangely enough, the exception doesn't occur when reading the annotations.properties files in org.eclipse.mat.report. Perhaps ResoruceBundle was attempting to read the file as a class file. The similarity of names of IconLabels.java and iconlabels.properties might be the reason - I tried renaming the properties file to icon_labels.properties and the problem went away. Perhaps you could check too.
I've made changes to the patch so that for tables just the first column of the item and the graphic is read out for the name, and the whole row (and column names if required) can be read by JAWS . For trees, the whole row including columns is given as the name and then is read out by JAWS. I've also used findWidget for trees. I've renamed iconlabels.properties to icon_labels.properties to avoid the NoClassDefFoundError. I'll check in this version - please test.
Changes applied.
I am closing the bug now. In case further improvements are needed let us track them in separate messages.
