Retrieve the current language from an editor object - coffeescript

Using this code I can subscribe to each editor's events in Atom:
#subscriptions = new CompositeDisposable
#subscriptions.add atom.workspace.observeTextEditors (editor) =>
// any code to do on the editor
However, I only want to subscribe to the editor if the editor is using a specific language. How can I retrieve that language from the editor object?

This is actually quite easy! The key is the Grammar object.
#subscriptions = new CompositeDisposable
#subscriptions.add atom.workspace.observeTextEditors (editor) =>
if editor.getGrammar().name == "name_of_language"
// code for this editor

Related

How to search for and highlight a substring in Codemirror 6?

I'm building a simple code editor to help children learn HTML. One feature I'm trying to add is that when users mouseover their rendered code (in an iframe), the corresponding HTML code in the editor is highlighted. So, for example, if a user mouses-over an image of kittens, the actual code, , would be highlighted in the editor.
Mousing-over the iframe to get the html source for that element is the easy part, which I've done (using document.elementFromPoint(e.clientX, e.clientY in the iframe itself, and posting that up to the parent) - so that's not the part I need help with. The part I can't figure out is how to search for and highlight that string of selected code in the code editor.
I'm using Codemirror 6 for this project, as it seems as it will give me the most flexibility to create such a feature. However, as a Codemirror 6 novice, I'm struggling with the documentation to find out where I should start. It seems like the steps I need to complete to accomplish this are:
Search for a range in the editor's text that matches a string (ie.'<img src="kittens.gif"').
Highlight that range in the editor.
Can anyone out there give me some advice as to where in the Codemirror 6 API I should look to start implementing this? It seems like it should be easy, but my unfamiliarity with the Codemirror API and the terse documentation is making this difficult.
1. Search for a range in the editor's text that matches a string (ie.'<img src="kittens.gif"').
You can use SearchCursor class (iterator) to get the character's range where is located the DOM element in your editor.
// the import for SearchCursor class
import {SearchCursor} from "#codemirror/search"
// your editor's view
let main_view = new EditorView({ /* your code */ });
// will create a cursor based on the doc content and the DOM element as a string (outerHTML)
let cursor = new SearchCursor(main_view.state.doc, element.outerHTML);
// will search the first match of the string element.outerHTML in the editor view main_view.state.doc
cursor.next()
// display the range where is located your DOM element in your editor
console.log(cursor.value);
2. Highlight that range in the editor.
As described in the migration documentation here, marked text is replace by decoration. To highlight a range in the editor with codemirror 6, you need to create one decoration and apply it in a dispatch on your view. This decoration need to be provide by an extension that you add in the extensions of your editor view.
// the import for the 3 new classes
import {StateEffect, StateField} from "#codemirror/state"
import {Decoration} from "#codemirror/view"
// code mirror effect that you will use to define the effect you want (the decoration)
const highlight_effect = StateEffect.define();
// define a new field that will be attached to your view state as an extension, update will be called at each editor's change
const highlight_extension = StateField.define({
create() { return Decoration.none },
update(value, transaction) {
value = value.map(transaction.changes)
for (let effect of transaction.effects) {
if (effect.is(highlight_effect)) value = value.update({add: effect.value, sort: true})
}
return value
},
provide: f => EditorView.decorations.from(f)
});
// this is your decoration where you can define the change you want : a css class or directly css attributes
const highlight_decoration = Decoration.mark({
// attributes: {style: "background-color: red"}
class: 'red_back'
});
// your editor's view
let main_view = new EditorView({
extensions: [highlight_extension]
});
// this is where the change takes effect by the dispatch. The of method instanciate the effect. You need to put this code where you want the change to take place
main_view.dispatch({
effects: highlight_effect.of([highlight_decoration.range(cursor.value.from, cursor.value.to)])
});
Hope it will help you to implement what you want ;)
Have a look at #codemirror/search.
Specifically, the source code implementation of Selection Matching may be of use for you to adapt.
It uses Decoration.mark over a range of text.
You can use SearchCursor to iterate over ranges that match your pattern (or RegExpCursor)
Use getSearchCursor, something like this:
var cursor = cmEditor.getSearchCursor(keyword , CodeMirror.Pos(cmEditor.firstLine(), 0), {caseFold: true, multiline: true});
if(cursor.find(false)){ //move to that position.
cmEditor.setSelection(cursor.from(), cursor.to());
cmEditor.scrollIntoView({from: cursor.from(), to: cursor.to()}, 20);
}
Programmatically search and select a keyword
Take a look at getSearchCursor source code it it give some glow about how it works and its usage.
So use getSearchCursor for finding text and optionally use markText for highlighting text because you can mark text with setSelection method of editor.
Selection Marking Demo
var editor = CodeMirror.fromTextArea(document.getElementById("code"), {
lineNumbers: true,
styleSelectedText: true
});
editor.markText({line: 6, ch: 26}, {line: 6, ch: 42}, {className: "styled-background"});
And it seem this is what you are looking for:
codemirror: search and highlight multipule words without dialog
RegExpCursor is another option that you can use:
new RegExpCursor(
text: Text,
query: string,
options⁠?: {ignoreCase⁠?: boolean},
from⁠?: number = 0,
to⁠?: number = text.length
)
Sample usage at:
Replacing text between dollar signs for Mathml expression.

VSCode API - 'textInputFocus' for webview or custom undo handling

I am working on VSCode extension implementation.
I am using webview for my extension - in result there is something similar to visual editor, when you can select items and edit.
In result I want to implement custom undo/redo handling for webview.
I have following code to handle VSCode's 'undo'/'redo' commands:
let undoCommand: Disposable;
let redoCommand: Disposable;
const registerCommands = () => {
undoCommand = commands.registerCommand('undo', async (args) => {
// Call custom undo handler
triggerCustomUndo(appJsonFilePath, extensionWebView.webview);
// Execute default undo handler
return commands.executeCommand('default:undo', args);
});
redoCommand = commands.registerCommand('redo', async (args) => {
// Call custom redo handler
triggerCustomRedo(appJsonFilePath, extensionWebView.webview);
// Execute default redo handler
return commands.executeCommand('default:redo', args);
});
};
extensionWebView.onDidChangeViewState((action: WebviewPanelOnDidChangeViewStateEvent) => {
if (!action.webviewPanel.visible || !action.webviewPanel.active) {
undoCommand.dispose();
redoCommand.dispose();
} else {
registerCommands();
}
});
registerCommands();
It works for me.
In result my custom undo/redo handler is called when I select 'undo'/'redo' from VSCode's menu:
Problem is that when I am using 'Ctrl+Z'|'Command+Z' shortcut, then 'undo' command is not called for webview.
This happens because of following 'when' clause in default keybindings:
If I remove 'textInputFocus' statement from 'when' clause, then 'undo' command is called for webview when keyboard shortcut is used.
Some information regarding 'when' contexts - https://github.com/microsoft/vscode-docs/blob/master/docs/getstarted/keybindings.md#contexts
Question:
Is there a way how I can set 'textInputFocus' to 'true', when I am using webview?
Alternative way could be:
I can read keybinding attachments
Default - 'vscode://defaultsettings/keybindings.json'
Custom/Overwritten:
Windows - %APPDATA%\Code\User\keybindings.json;
MacOS - $HOME/Library/Application Support/Code/User/keybindings.json;
Linux - $HOME/.config/Code/User/keybindings.json;
Attach to keyboard key down event manually and handle event to detect 'undo'/'redo' key combination;
That should work, but if I could somehow set 'textInputFocus' to 'true' for webview then it would be much easier.
Or maybe there is other simpler solution available?
I found way how to set 'textInputFocus' manually:
vscode.commands.executeCommand('setContext', 'textInputFocus', true);

Eclipse E4 RCP StyledText obtain INSERT KEY state

For an RCP E4 Text Editor application implemented with a StyledText/SourceViewer it is necessary receive the status of the inset key.
Once received the state (insert, smart-insert), the application shall modify the cursor icon and notify other parts the INSERT state (i.e. notify to the status bar control like in a normal plain text editor behavior).
SWT.INSERT only listens for the key to be pressed, but nothing if the StyledText is in INSERT MODE.
styledText.addKeyListener(new KeyAdapter(){
public void keyPressed(KeyEvent e){
if(e.keyCode == SWT.INSERT){
System.out.println("INSERT KEY PRESSED!!!");
}
}
};
I have avoided to extend
org.eclipse.ui.texteditor.AbstractTextEditor
and use the method
getInsertMode()
since the application is intended to be pure E4 text editor.
Any hint?
Thanks in advance
First off you need to tell the StyledText not to do the default action when it sees the Insert key:
textWidget.setKeyBinding(SWT.INSERT, SWT.NULL);
Next you need to define a Command, Handler and Key Binding in the context for the editor to deal with the Insert key.
The Handler for the insert command can update the status display and shoyld then tell the StyledText to update the overwrite mode:
textWidget.invokeAction(ST.TOGGLE_OVERWRITE);
Also note that Mac keyboards don't have an Insert key!
Since I found some difficulties to deal with the INSERT_KEY within a sourceviewer control for E4 RCP text editor, I will write extra details to gregg449's answer (great help from him as everytime!).
Following the above answer, I have created Binding Context, Binding Table, Command, Handler and added the Binding Context to the required Part (the part implementing the SourceViewer).
The next code is for SourceViewer and InserKey Handler:
public class CheckKeyBindingSourceViewer extends ITextEditorPart{
public SourceViewer sv = null;
public StyledText st = null;
#PostConstruct
public void postConstruct(Composite parent) {
sv = new SourceViewer(parent, null, null, true, SWT.MULTI | SWT.V_SCROLL |SWT.H_SCROLL);
IDocument doc = new Document("");
sv.setDocument(doc);
st = sv.getTextWidget();
//tell the StyledText not to do the default action when it sees the Insert key
st.setKeyBinding(SWT.INSERT, SWT.NULL);
}
}
public class InsertKeyHandler {
#Execute
public void execute(#Named(IServiceConstants.ACTIVE_PART) MPart activePart) {
if (activePart.getObject() instanceof ITextEditorPart){
ITextEditorPart theSourceViewer = (ITextEditorPart) activePart.getObject();
theSourceViewer.st.invokeAction(ST.TOGGLE_OVERWRITE);
//TODO
//Change cursor sourcewiewer, notify to Statusbar...
}
}
}
The next figure shows the Application.e4xmi with the Binding Context and Binding Table created.
Note that if you do not add the supplementary tag "type:user" to the Binding Table, the bindings are not working at all.
This is not reflected into vogella's tutorial (http://www.vogella.com/tutorials/EclipseRCP/article.html) neither his book.
The only place I found this information was at stackoverflow question:
eclipse rcp keybindings don't work
I'm using eclipse Mars (4.5.0) for both Linux and Windows, I do not know if for newer verions this 'bug' is solved.

Eclipse: selection autocopy to clipboard

I love an Emacs feature to copy selection to clipboard automatically. Is it possible to do the same on Eclipse?
Environment: Windows XP, Helios
To copy a String from Eclipse to the clipboard, you can use
void copyToClipboard (String toClipboard, Display display){
String toClipboard = "my String";
Clipboard clipboard = new Clipboard(display);
TextTransfer [] textTransfer = {TextTransfer.getInstance()};
clipboard.setContents(new Object [] {toClipboard}, textTransfer);
clipboard.dispose();
}
Then you can call this method from a MouseAdapter or KeyAdapter, depending on where you want to get your String from. In your case it could be MouseAdapter, which listens to doubleclicks, gets the current cursor position of the text, marks the word and then adds the String to the clipboard.
edit to answer a question: You can set up your own MouseAdapater and attach it to buttons, text fields or whateer you like. Here's an example for a button:
Button btnGo1 = new Button(parent, SWT.NONE);
btnGo1.setText("Go");
btnGo1.addMouseListener(new MouseAdapter() {
#Override
public void mouseDoubleClick(MouseEvent e) {
//do what you want to do in here
}
});
If you want to implement mouseUp and mouseDown events, too, you can just add MouseListenerinstead of the Adapter. The only advantage of the Adapter is, that you don't have to override the other methods of the interface.
Since the original question was to automatically get the selection of the text of an editor: the way to get the selection from an editor is explained here.
You can try this plugin. Along with auto copy points mentioned in Eclipse show number of lines and/or file size also addressed.

Eclipse plugin : Get the enclosing class and member name

I have created a Eclipse plug in to printout the object in selection on press of a short cut key.
I have been able to do this ,but i also would like to add the current method and current class name in the log. I am not sure how to proceede further. I tried to search for breadcrumb API but i was not able to reference the package from my project. I am quite new to plugin developement could someone guide me as to how to achive my goal. Thanks in advance.
It really hard to get that stuff from Breadcrumb, you would have to use reflection to get it.
Here is the code to get current method from editor.
ITextEditor editor = (ITextEditor) PlatformUI.getWorkbench()
.getActiveWorkbenchWindow().getActivePage().getActiveEditor();
ITextSelection selection = (ITextSelection) editor
.getSelectionProvider().getSelection();
IEditorInput editorInput = editor.getEditorInput();
IJavaElement elem = JavaUI.getEditorInputJavaElement(editorInput);
if (elem instanceof ICompilationUnit) {
ICompilationUnit unit = (ICompilationUnit) elem;
IJavaElement selected = unit.getElementAt(selection.getOffset());
System.out.println("selected=" + selected);
System.out.println("selected.class=" + selected.getClass());
}