Is there any built-in functionality or plugin that would allow me to define my own custom regions for code folding? I am using version 4.8.0 (Photon release)
In particular, I am interested in folding certain parts of .java files where I am needing to declare a lot of variables.
To add folding regions to Java sources, you can implement the extension "org.eclipse.jdt.ui.foldingStructureProvider". To do this, you create an eclipse plug-in project (requires Eclipse PDE) and add an extension point to your plugin.xml. Then you create a class that implements IJavaFoldingStructureProvider and possibly IJavaFoldingStructureProviderExtension.
Folding regions are added like this:
FoldingStructureComputationContext context
IRegion normalized = alignRegion(new Region(offset, length), context);
if (normalized != null) {
Position position = createMemberPosition(normalized, (IMember) element);
if (position != null) {
boolean isCollapsed = false, isComment = false;
context.addProjectionRange(new JavaProjectionAnnotation(isCollapsed, element, isComment), position);
}
}
See DefaultJavaFoldingStructureProvider for alignRegion, createMemberPosition, etc. offset and length are determined by your code.
Related
I'm using Itext 7 and their html2Pdf lib.
Is there a way to implement for example cmyk colors.
.wootWorkingCMYK-color{
color: cmyk( 1 , 0.69 , 0.08 , 0.54);
}
I know the itext core part pretty good, looking for away to use the html2Pdf side. I'm aware of the CssApplierFactory but this seems to be to far up the chain.
Well, of course there is a way of processing custom CSS properties like cmyk colors, but unfortunately the code would be quite bulky and you will need to write quite some code for different cases. I will show how to apply custom color for font, but e.g. for backgrounds, borders or other cases you will need to write separate code in a similar way. Reason behind it is that iText layout structure, although designed with HTML/CSS in mind, is not 100% similar and has some differences you have to code around.
Having that said, if you can fork, build and use your custom version from sources, this is the way I would advice to go. Although it has drawbacks like having to rebase to get updates, the solution would be simpler and more generic. To do that, search for usages of CssUtils.parseRgbaColor in pdfHTML module, and you will find that it is used in BackgroundApplierUtil, BorderStyleApplierUtil, FontStyleApplierUtil, OutlineApplierUtil. There you will find code like
if (!CssConstants.TRANSPARENT.equals(cssColorPropValue)) {
float[] rgbaColor = CssUtils.parseRgbaColor(cssColorPropValue);
Color color = new DeviceRgb(rgbaColor[0], rgbaColor[1], rgbaColor[2]);
float opacity = rgbaColor[3];
transparentColor = new TransparentColor(color, opacity);
} else {
transparentColor = new TransparentColor(ColorConstants.BLACK, 0f);
}
Which I belive you can tweak to process cmyk as well, knowing that you know core part pretty well.
Now, the solution without custom pdfHTML version is to indeed start with implementing ICssApplierFactory, or subclassing default implementation DefaultCssApplierFactory. We are mostly interested in customizing implementation of SpanTagCssApplier and BlockCssApplier, but you can consult with DefaultTagCssApplierMapping to get the full list of appliers and cases they are used in, so that you can decide which of them you want to process in your code.
I will show you how to add support for custom color space for font color in the two main applier classes I mentioned and you can work from there.
private static class CustomCssApplierFactory implements ICssApplierFactory {
private static final ICssApplierFactory DEFAULT_FACTORY = new DefaultCssApplierFactory();
#Override
public ICssApplier getCssApplier(IElementNode tag) {
ICssApplier defaultApplier = DEFAULT_FACTORY.getCssApplier(tag);
if (defaultApplier instanceof SpanTagCssApplier) {
return new CustomSpanTagCssApplier();
} else if (defaultApplier instanceof BlockCssApplier) {
return new CustomBlockCssApplier();
} else {
return defaultApplier;
}
}
}
private static class CustomSpanTagCssApplier extends SpanTagCssApplier {
#Override
protected void applyChildElementStyles(IPropertyContainer element, Map<String, String> css, ProcessorContext context, IStylesContainer stylesContainer) {
super.applyChildElementStyles(element, css, context, stylesContainer);
String color = css.get("color2");
if (color != null) {
color = color.trim();
if (color.startsWith("cmyk")) {
element.setProperty(Property.FONT_COLOR, new TransparentColor(parseCmykColor(color)));
}
}
}
}
private static class CustomBlockCssApplier extends BlockCssApplier {
#Override
public void apply(ProcessorContext context, IStylesContainer stylesContainer, ITagWorker tagWorker) {
super.apply(context, stylesContainer, tagWorker);
IPropertyContainer container = tagWorker.getElementResult();
if (container != null) {
String color = stylesContainer.getStyles().get("color2");
if (color != null) {
color = color.trim();
if (color.startsWith("cmyk")) {
container.setProperty(Property.FONT_COLOR, new TransparentColor(parseCmykColor(color)));
}
}
}
}
}
// You might want a safer implementation with better handling of corner cases
private static DeviceCmyk parseCmykColor(String color) {
final String delim = "cmyk(), \t\r\n\f";
StringTokenizer tok = new StringTokenizer(color, delim);
float[] res = new float[]{0, 0, 0, 0};
for (int k = 0; k < 3; ++k) {
if (tok.hasMoreTokens()) {
res[k] = Float.parseFloat(tok.nextToken());
}
}
return new DeviceCmyk(res[0], res[1], res[2], res[3]);
}
Having that custom code, you should configure the ConverterProperties accordingly and pass it to HtmlConverter:
ConverterProperties properties = new ConverterProperties();
properties.setCssApplierFactory(new CustomCssApplierFactory());
HtmlConverter.convertToPdf(..., properties);
You might have noticed that I used color2 instead of color, and this is for a reason. pdfHTML has a mechanism of CSS property validation (as browsers do as well), to discard invalid CSS properties when calculating effective properties for an element. Unfortunately, there is no mechanism of customizing this validation logic currently and of course it treats cmyk colors as invalid declarations at the moment. Thus, if you really want to have custom color property, you will have to preprocess your HTML and replace declarations like color: cmyk... to color2: cmyk.. or whatever the property name you might want to use.
As I mentioned at the start of the answer, my recommendation is to build your own custom version :)
I am building an application with eclipse e4 RCP. I have a navigator (similar to Navigator in eclipse IDE) and I would like to link it to an editor (similar to how a file in Navigator in eclipse IDE is linked to an editor). Currently I am using EPartService to open up my editor Part (by creating a new instance) when the user double clicks on a file in the Navigator tree. But I would like to pass it a parameter (a String or an Object) to let it know which file to open in the editor. I want to be able to open multiple editors for different nodes of the Navigator tree. I have done a lot of research on internet but could not find a solution. I think its a common problem and the e4 framework should provide an mechanism to pass such parameters from one Part to another Part. Current code is as below:
viewer.addDoubleClickListener(event -> {
final IStructuredSelection selection = (IStructuredSelection) event.getSelection();
FileNode file = null;
boolean partExists = false;
if (selection.getFirstElement() instanceof FileNode ) {
file = (FileNode ) selection.getFirstElement();
for (MPart part1 : partService.getParts()) {
if (part1.getLabel().equals(file.getName())) {
partService.showPart(part1, PartState.ACTIVATE);
partExists = true;
break;
}
}
if (!partExists) {
MPart part2 = partService
.createPart("com.parts.partdescriptor.fileeditor");
part2.setLabel(file.getName());
partService.showPart(part2, PartState.ACTIVATE);
}
}
});
Is it possible to say something like part2.setParameter("PARAM_NAME", "FILE_NAME"); ?
When you have an MPart you can call:
MPart mpart = ...
MyClass myClass = (MyClass)mpart.getObject();
to get your class for the part (the class defined in the 'Class URI' for the part in the Application.e4xmi). You can then call any methods you have defined on your part class.
You can also set data in the 'transient data' area of a part:
mpart.getTransientData().put("key", "data");
Object data = mpart.getTransientData().get("key");
I have a question concerning the grid widget. This widget is also available in vanilla GWT through the "GWT-Widgets 7.4.3" download.
But my question is how do you enable sorting in this widget in GWT ?
I started from the example provided by Vaadin : https://github.com/Artur-/grid-gwt
But when you do a "setSortable(true)" on a Column the only thing that happens is that an arrow of sort direction is drawn in the table header when clicking it. The table itself isn't re-sorted.
Also executing a sort method on the grid with a column and a direction has no effect.
In the book of vaadin https://vaadin.com/book/-/page/components.grid.html I noted the following : "The container data source must support sorting. At least, it must implement Container.Sortable.".
So I suppose that ListDataSource is not suited for sorting.
But what else can I use in GWT so that it sorts ? In the book of Vaadin I see that a
BeanItemContainer is used, but this is not available in "GWT-Widgets 7.4.3" as this seems to be a server component.
So it comes down to this question: How do I enable sorting on the Vaadin grid in a vanilla GWT project ?
thanks
Frank
I have no experience with Vaadin, but in plain GWT you would do something like this (where T is your object):
ListDataProvider<T> dataProvider = new ListDataProvider<T>();
List<T> displayItems = dataProvider.getList();
ListHandler<T> sortHandler = new ListHandler<T>(displayItems);
Then, to make a column sortable, you need to tell the sortHandler how to sort these objects:
dateColumn.setSortable(true);
dateColumn.setDefaultSortAscending(false);
sortHandler.setComparator(dateColumn, new Comparator<Item>() {
#Override
public int compare(Item o1, Item o2) {
if (o1.getDate() != null) {
return (o2.getDate() != null) ?
o1.getDate().compareTo(o2.getDate()) : 1;
}
return -1;
}
});
I am building an application where i need to parse a pdf which is generated by a system and with that parsed information i need to populate my applications database columns but unfortunaltely the pdf structure that i am dealing with is having a column called comments which has both text and image. I found the way of reading the images and text separately from the pdf but my ultimate aim was to add a place holder something like {2} in the place of image inside the parsed content and whenever my parser ( the application code ) parse this line the system will render the appropriate image in that area which is also stored in a separate table inside my application.
Please help me with resolving this problem.
Thanks in advance.
As already mentioned in comments, a solution would be to essentially use a customized text extraction strategy to insert a "[ 2]" text chunk at the coordinates of the image.
Code
You can e.g. extend the LocationTextExtractionStrategy like this:
class SimpleMixedExtractionStrategy extends LocationTextExtractionStrategy
{
SimpleMixedExtractionStrategy(File outputPath, String name)
{
this.outputPath = outputPath;
this.name = name;
}
#Override
public void renderImage(final ImageRenderInfo renderInfo)
{
try
{
PdfImageObject image = renderInfo.getImage();
if (image == null) return;
int number = counter++;
final String filename = String.format("%s-%s.%s", name, number, image.getFileType());
Files.write(new File(outputPath, filename).toPath(), image.getImageAsBytes());
LineSegment segment = UNIT_LINE.transformBy(renderInfo.getImageCTM());
TextChunk location = new TextChunk("[" + filename + "]", segment.getStartPoint(), segment.getEndPoint(), 0f);
Field field = LocationTextExtractionStrategy.class.getDeclaredField("locationalResult");
field.setAccessible(true);
List<TextChunk> locationalResult = (List<TextChunk>) field.get(this);
locationalResult.add(location);
}
catch (IOException | NoSuchFieldException | SecurityException | IllegalArgumentException | IllegalAccessException ioe)
{
ioe.printStackTrace();
}
}
final File outputPath;
final String name;
int counter = 0;
final static LineSegment UNIT_LINE = new LineSegment(new Vector(0, 0, 1) , new Vector(1, 0, 1));
}
(Unfortunately for this kind of work, some members of LocationTextExtractionStrategy are private. Thus, I used some Java reflection. Alternatively you can copy the whole class and change your copy accordingly.)
Example
Using that strategy you can extract mixed contents like this:
#Test
public void testSimpleMixedExtraction() throws IOException
{
InputStream resourceStream = getClass().getResourceAsStream("book-of-vaadin-page14.pdf");
try
{
PdfReader reader = new PdfReader(resourceStream);
PdfReaderContentParser parser = new PdfReaderContentParser(reader);
SimpleMixedExtractionStrategy listener = new SimpleMixedExtractionStrategy(OUTPUT_PATH, "book-of-vaadin-page14");
parser.processContent(1, listener);
Files.write(new File(OUTPUT_PATH, "book-of-vaadin-page14.txt").toPath(), listener.getResultantText().getBytes());
}
finally
{
if (resourceStream != null)
resourceStream.close();
}
}
E.g. for my test file (which contains page 14 of the Book of Vaadin):
You get this text
Getting Started with Vaadin
• A version of Book of Vaadin that you can browse in the Eclipse Help system.
You can install the plugin as follows:
1. Start Eclipse.
2. Select Help Software Updates....
3. Select the Available Software tab.
4. Add the Vaadin plugin update site by clicking Add Site....
[book-of-vaadin-page14-0.png]
Enter the URL of the Vaadin Update Site: http://vaadin.com/eclipse and click OK. The
Vaadin site should now appear in the Software Updates window.
5. Select all the Vaadin plugins in the tree.
[book-of-vaadin-page14-1.png]
Finally, click Install.
Detailed and up-to-date installation instructions for the Eclipse plugin can be found at http://vaad-
in.com/eclipse.
Updating the Vaadin Plugin
If you have automatic updates enabled in Eclipse (see Window Preferences Install/Update
Automatic Updates), the Vaadin plugin will be updated automatically along with other plugins.
Otherwise, you can update the Vaadin plugin (there are actually multiple plugins) manually as
follows:
1. Select Help Software Updates..., the Software Updates and Add-ons window will
open.
2. Select the Installed Software tab.
14 Vaadin Plugin for Eclipse
and two images book-of-vaadin-page14-0.png
and book-of-vaadin-page14-1.png
in OUTPUT_PATH.
Improvements to make
As also already mentioned in comments, this solution is for the easy situation in which the image has text above and/or below but neither left nor right.
If there is text left and/or right, too, there is the problem that the code above calculates LineSegment segment as the bottom line of the image but the text strategy usually works with the base line of text which is above the bottom line.
But in this case one first has to decide at which position on which line one wants the marker in the text to be anyways. Having decided that, one can adapt the source above.
I successfully extended the PyDev editor in Eclipse with a side-by-side display, but I can't copy the contents of the extra SourceViewer that I added. I can select some text in the display, but when I press Ctrl+C, it always copies the main PyDev editor's selected text.
I found an article on key bindings in Eclipse editors, but the code there seems incomplete and a bit out-of-date. How can I configure the copy command to copy from whichever SourceViewer has focus?
The reason I want to do this is that I've written a tool for live coding in Python, and it would be much easier for users to submit bug reports if they could just copy the display and paste it into the bug description.
David Green's article was a good start, but it took a bit of digging to make it all work. I published a full example project on GitHub, and I'll post a couple of snippets here.
The TextViewerSupport class wires up a new action handler for each command you want to delegate to the extra text viewer. If you have multiple text viewers, just instantiate a TextViewerSupport object for each of them. It wires up everything in its constructor.
public TextViewerSupport(TextViewer textViewer) {
this.textViewer = textViewer;
StyledText textWidget = textViewer.getTextWidget();
textWidget.addFocusListener(this);
textWidget.addDisposeListener(this);
IWorkbenchWindow window = PlatformUI.getWorkbench()
.getActiveWorkbenchWindow();
handlerService = (IHandlerService) window
.getService(IHandlerService.class);
if (textViewer.getTextWidget().isFocusControl()) {
activateContext();
}
}
The activateContext() method has a list of all the commands you want to delegate, and registers a new handler for each one. This was one of the changes from David's article; his ITextEditorActionDefinitionIds has been deprecated and replaced with IWorkbenchCommandConstants.
protected void activateContext() {
if (handlerActivations.isEmpty()) {
activateHandler(ITextOperationTarget.COPY,
IWorkbenchCommandConstants.EDIT_COPY);
}
}
// Add a single handler.
protected void activateHandler(int operation, String actionDefinitionId) {
StyledText textWidget = textViewer.getTextWidget();
IHandler actionHandler = createActionHandler(operation,
actionDefinitionId);
IHandlerActivation handlerActivation = handlerService.activateHandler(
actionDefinitionId, actionHandler,
new ActiveFocusControlExpression(textWidget));
handlerActivations.add(handlerActivation);
}
// Create a handler that delegates to the text viewer.
private IHandler createActionHandler(final int operation,
String actionDefinitionId) {
Action action = new Action() {
#Override
public void run() {
if (textViewer.canDoOperation(operation)) {
textViewer.doOperation(operation);
}
}
};
action.setActionDefinitionId(actionDefinitionId);
return new ActionHandler(action);
}
The ActiveFocusControlExpression gives the new handler a high enough priority that it will replace the standard handler, and it's almost identical to David's version. However, to get it to compile, I had to add extra dependencies to my plug-in manifest: I imported packages org.eclipse.core.expressions and org.eclipse.ui.texteditor.