AvalonEdit :: How do I preserve current state in the UndoStack? - avalonedit

I am currently working on implementing AvalonEdit in an HTML WYSIWYG/"Source Code" side-by-side editor. When the user switches from Design Mode (a RichTextBox) to Source Mode (AvalonEdit TextEditor) the XAML from the RTB is converted to HTML and written to the TextEditor.Document.Text property.
This apparently wipes out the undo stack.
How can I push the state of the Document to the UndoStack so the user can "go back"? I tried wrapping the write operation in a RunUpdate() IDisposable, but that didn't work:
using (var _ = TextEditor.Document.RunUpdate())
{
TextEditor.Document.Text = html;
}
Any assistance would be greatly appreciated.

Since this is a couple years late, I'm not sure if it answers the question directly. However, the current release of AvalonEdit functions such that setting TextEditor.Text will clear the undo stack, but modifying TextEditor.Document.Text will not. (This runs counter to the behavior observed by the asker, so perhaps it has changed in the couple years since). Looking at the source code, TextEditor.Document.Text appears to execute code equivalent to
this.Replace(0, this.TextLength, value);
so perhaps a similar call would work even on older versions of the library.

Related

Meteor how to save templates in mongo

I want to give my users the possibility to create document templates (contracts, emails, etc.)
The best option I figured out would be to store these document templates in mongo (maybe I'm wrong...)
I've been searching for a couple of hours now but I can't figure out how to render these document template with their data context.
Example:
Template stored in Mongo: "Dear {{firstname}}"
data context: {firstname: "Tom"}
On Tom's website, He should read: "Dear Tom"
How can I do this?
EDIT
After some researches, I discovered a package called spacebars-compiler that brings the option to compile to the client:
meteor add spacebars-compiler
I then tried something like this:
Template.doctypesList.rendered = ->
content = "<div>" + this.data.content + "</div>"
template = Spacebars.compile content
rendered = UI.dynamic(template,{name:"nicolas"})
UI.insert(rendered, $(this).closest(".widget-body"))
but it doesn't work.
the template gets compiled but then, I don't know how to interpret it with its data context and to send it back to the web page.
EDIT 2
I'm getting closer thanks to Tom.
This is what I did:
Template.doctypesList.rendered = ->
content = this.data.content
console.log content
templateName = "template_#{this.data._id}"
Template.__define__(templateName, () -> content)
rendered = UI.renderWithData(eval("Template.#{templateName}"),{name:"nicolas"})
UI.insert(rendered, $("#content_" + this.data._id).get(0))
This works excepted the fact that the name is not injected into the template. UI.renderWithData renders the template but without the data context...
The thing your are missing is the call to (undocumented!) Template.__define__ which requires the template name (pick something unique and clever) as the first argument and the render function which you get from your space bars compiler. When it is done you can use {{> UI.dynamic}} as #Slava suggested.
There is also another way to do it, by using UI.Component API, but I guess it's pretty unstable at the moment, so maybe I will skip this, at least for now.
Use UI.dynamic: https://www.discovermeteor.com/blog/blaze-dynamic-template-includes/
It is fairly new and didn't make its way to docs for some reason.
There are few ways to achieve what you want, but I would do it like this:
You're probably already using underscore.js, if not Meteor has core package for it.
You could use underscore templates (http://underscorejs.org/#template) like this:
var templateString = 'Dear <%= firstname %>'
and later compile it using
_.template(templateString, {firstname: "Tom"})
to get Dear Tom.
Of course you can store templateString in MongoDB in the meantime.
You can set delimiters to whatever you want, <%= %> is just the default.
Compiled template is essentially htmljs notation Meteor uses (or so I suppose) and it uses Template.template_name.lookup to render correct data. Check in console if Template.template_name.lookup("data_helper")() returns the correct data.
I recently had to solve this exact (or similar) problem of compiling templates client side. You need to make sure the order of things is like this:
Compiled template is present on client
Template data is present (verify with Template.template_name.lookup("data_name")() )
Render the template on page now
To compile the template, as #apendua have suggested, use (this is how I use it and it works for me)
Template.__define__(name, eval(Spacebars.compile(
newHtml, {
isTemplate: true,
sourceName: 'Template "' + name + '"'
}
)));
After this you need to make sure the data you want to render in template is available before you actually render the template on page. This is what I use for rendering template on page:
UI.DomRange.insert(UI.render(Template.template_name).dom, document.body);
Although my use case for rendering templates client side is somewhat different (my task was to live update the changed template overriding meteor's hot code push), but this worked best among different methods of rendering the template.
You can check my very early stage package which does this here: https://github.com/channikhabra/meteor-live-update/blob/master/js/live-update.js
I am fairly new to real-world programming so my code might be ugly, but may be it'll give you some pointers to solve your problem. (If you find me doing something stupid in there, or see something which is better done some other way, please feel free to drop a comment. That's the only way I get feedback for improvement as I am new and essentially code alone sitting in my dark corner).

Plone Conditional - If Content Type is Versionable

Is there a simple way to check if a content-type, or a specific object, has Versioning enabled/disabled in Plone (4.3.2)?
For context, I am making some unique conditionals around portal_actions. So instead of checking path('object/##iterate_control').checkout_allowed(), I need to first see if versioning is even enabled. Otherwise, the action in question does not display for items that have versioning disabled, because obviously it isn't checkout_allowed.
I didn't have any luck with good ole Google, and couldn't find this question anywhere here, so I hope it's not a dupe. Thanks!
I was able to get this working by creating a new script, importing getToolByName, and checking current content type against portal_repository.getVersionableContentTypes(). Then just included that script in the conditional.
I was looking for something like this that already existed, so if anyone knows of one let me know. Otherwise, I've got my own now. Thanks again!
The first thing that checkout_allowed does is check if the object in question supports versioning at all:
if not interfaces.IIterateAware.providedBy(context):
return False
(the interface being plone.app.iterate.interfaces.IIterateAware:
class IIterateAware( Interface ):
"""An object that can be used for check-in/check-out operations.
"""
The semantics Interface.providedBy(instance) are a bit unfortunate for usage in conditions or TAL scripts, because you'd need to import the interface, but there's a reversal helper:
context.portal_interface.objectImplements(context,
'plone.app.iterate.interfaces.IIterateAware')

What determines sorting of files in a QFileDialog?

Users open files in our app through a QFileDialog. The order of the filenames is bizarre. What is determining the sorting order, and how can we make it sort by filenames, or otherwise impose our own sorting, perhaps giving it a pointer to our own comparison function?
The documentation and online forums haven't been helpful. Unless it's well hidden, there doesn't seem to be any sorting method, property, etc.
This is a primarily Linux app, but also runs on Macs. (I know nothing about Mac.)
Here is the juicy part of the source code:
QtFileDialog chooser(parent, caption, directory, filter);
/// QtFileDialog is our class derived from QFileDialog
chooser.setModal(true);
chooser.setAcceptMode(acceptMode);
chooser.setFileMode(fileMode);
QStringList hist = chooser.history();
chooser.setHistory(hist);
/* point "x" */
if(chooser.exec()) {
QStringList files = chooser.selectedFiles();
...blah blah blah...
From one of the answers, I tried an evil experiment, adding this ill-informed guesswork code at "point x":
QSortFilterProxyModel *sorter = new QSortFilterProxyModel();
sorter->sort(1); // ???
chooser.setProxyModel(sorter);
But this crashed spectacularly at a point about 33 subroutine calls deep from this level of code. I admit, even after reading the Qt4 documentation and sample code, I have no idea of the proper usage of QSortFilterProxyModel.
Are you using QFileDialog by calling exec()? If you are, you should have a button to switch the view to Detail View. This will give you some column headers that you can click on to sort the files. It should remember that mode the next time the dialog opens but you can force it by calling setViewMode(QFileDialog::Detail) before calling exec().
An alternative is to call the static function QFileDialog::getOpenFileName() which will open a file dialog that is native to the OS on which you are running. Your users may like the familiarity of this option better.
Update 1:
About sort order in screen cap from OP:
This screen capture is actually showing a sorted list. I don't know if the listing behaviour is originating from the Qt dialog or the underlying file system but I know Windows XP and later do it this way.
When sorting filenames with embedded numbers, any runs of consecutive digits are treated as a single number. With the more classic plain string sorting, files would be sorted like this:
A_A_10e0
A_A_9a05
Going character by character, the first 1 sorts before the 9.
.. But with numerical interpretation (as in Windows 7 at least), they are sorted as:
A_A_9a05
A_A_10e0
The 9 sorts before the 10.
So, the sorting you are seeing is alphabetical with numerical interpretation and not just straight character by character. Some deep digging may be required to see if that is Qt behaviour or OS behaviour and whether or not it can be configured.
Update 2:
The QSortFilterProxyModel will sort the strings alphabetically by default so there is not much work to using it to get the behavior you are looking for. Use the following code where you have "point x" in your example.. (you almost had it :)
QSortFilterProxyModel *sorter = new QSortFilterProxyModel();
sorter->setDynamicSortFilter(true); // This ensures the proxy will resort when the model changes
chooser.setProxyModel(sorter);
I think what you need to do is create a QSortFilterProxyModel which you then set in your QFileDialog with QFileDialog::setProxyModel(QAbstractProxyModel * proxyModel)
Here are some relevant links to the Qt 4.6 docs about it.
http://doc.trolltech.com/4.6/qfiledialog.html#setProxyModel
http://doc.trolltech.com/4.6/qsortfilterproxymodel.html#details
I don't think it depends upon the implementation of Qt libraries... But upon the Native OS implementation..
For example in Windows,
if you use QFileDialog, it will display the Files and Directories by Name sorted.. It is the same when used in other applications. In the sense that, if you try to open a file through MS- Word, it indeed displays the Files and directories as Name sorted by default..
And am not sure about other environments since am not used to them...
But in Windows, you can change the sorted order by right-click in the area of Files and Directories display and can select the options you like.. For e.g like Name,size,type, modified... And also which is similar, when you use an MS-Word application...
So, I believe it does depend on the Native OS implementation and not on QFileDialog's...

Is there a way to wait for and get a key press from a (remote) terminal session?

I've been playing around with some ANSI stuff (like colors etc.) in java and php (from scratch) and I'm trying to find a way to basically wait for a key press. I'd like to have something like the following pseudo code at the end of my main event loop:
If (KeyPressed)
Begin
var event = new KeyboardEvent();
event.Key = ReadKey();
this.BubbleEvent(event);
End
But everything I've been trying over the last couple days fails because the key presses only become available on STDIN after the user has pressed enter.
It doesn't matter much what language you answer in, but java, php, plain old c or c# would be nicest, and I cannot use any really spiffy library stuff because I need to port it to all four of those languages... I need this to work over a telnet or ssh connection, but my research so far suggests it is impossible unless you're working on the local machine.
Please prove me wrong.
The curses function cbreak(3) will disable line-buffering and erase/kill handling. You can do this yourself with stty(1) if you really want.
When your program dies and leaves the terminal in cbreak mode, you can usually use either stty sane or reset to bring the terminal back to a reasonable state.
From within Perl, you can use either the Term::ReadKey or the Curses module to manipulate the terminal. See the Term::ReadKey(3pm) or Curses(3pm) manpage for details.
From within C, you can use either ioctl(2) calls on the terminal device to turn on cbreak mode, or you can use curses. See the ncurses(3) manpage for details.
I know, this is an old thread, but I could not find a suitable answer anywhere else. So with some help from the senior programmers of my company I came up with this:
private void waitKeypress() throws IOException
{
System.in.read();
while ( System.in.available() > 0 )
{
System.in.read();
}
}
The part reading as much input as is available solved my problem that when used multiple times, "System.in.read()" alone does not always wait.
For me this does the trick, I use it like this:
doSomething();
waitKeypress();
doNextThing();
Hope it helps.
Kind regards,
Ralph

Are there solutions for streamlining the update of legacy code in multiple places?

I'm working in some old code which was originally designed for handling two different kinds of files. I was recently tasked with adding a new kind of file to this code. Most of my problems were solved by filling out an extensive XML file with a new entry that handled everything from what lists were named to how the file is written in plural lower case. But this ended up being insufficient, as there were maybe 50 different places in 24 different code files where I had to update hardcoded switch-statements that only branched for the original two file types.
Unfortunately there is no consistency in this; there are methods which operate half from the XML file, and half off of hardcode. Some of the files which look like they would operate off of the XML file don't, and some that I would expect that I'd need to update the hardcode don't need it. So the only way to find the majority of these is to run through testing the whole system when only part of it is operational, finding that one step to fix (when I'm lucky that error logging actually tells me what is going on), and then running the whole thing again. This wastes time testing the parts of the code which are already confirmed to work, time better spent testing the new parts I have to add on top of it all.
It's a hassle and a half, and to my luck I can expect that I will have to add yet another new kind of file in the near future.
Are there any solutions out there which can aid in this kind of endeavour? Something which I can input some parameters of current features, document what points in a whole code project actually need to be updated, and run something nice the next time I need to add a new feature to the code. It needn't even be fully automated, something that'll help me navigate straight to the specific points in everything and maybe even record what kind of parameters need to be loaded.
Doubt it matters specifically, but the code is comprised of ASP.NET pages, some ASP.NET controls, hundreds of C# code files, and a handful of additional XML files. It's all currently in a couple big Visual Studio 2008 projects.
Not exactly what you are describing, but if you can introduce a seam into the code and lay down some interfaces you can break out and mock, a suite of unit/integration tests would go a long way to helping you modify old code you may not fully understand well.
I completely agree with the comment about using Michael Feathers' book to learn how to wedge new tests into legacy code. I'd also strongly recommend Refactoring, by Martin Fowler. What it sounds like you need to do for your code is to implement the "Replace conditionals with polymorphism" refactoring.
I imagine your code today looks somewhat like this:
if (filetype == 23)
{
type23parser.parse(file);
}
else if (filetype == 69)
{
filestore = type69reader.read(file);
File newfile = convertFSto23(filestore);
type23parser.parse(newfile);
}
What you want to do is to abstract away all the "if (type == foo)" kinds of logic into strategy patterns that are created in a factory.
class FileRules : pReader(NULL), pParser(NULL)
{
private:
FileReaderRules *pReader;
FileParserRules *pParser;
public:
void read(File* inFile) {pReader->read(inFile);};
void parse(File* inFile) {pParser->parse(inFile);};
};
class FileRulesFactory
{
FileRules* GetRules(int inputFiletype, int parserType)
{
switch (inputFiletype)
{
case 23:
pReader = new ASCIIReader;
break;
case 69:
pReader = new EBCDICReader;
break;
}
switch (parserType)
... etc...
then your main line of code looks like this:
FileRules* rules = FileRulesFactory.GetRules(filetype, parsertype);
rules.read(file);
rules.parse(file);
Pull off this refactoring, and adding a new set of file types, parsers, readers, etc., becomes as simple as writing one exclusive to your new type.
Of course, go read the book. I vastly oversimplified it here, and probably got stuff wrong, but you should get the general idea of how to approach it from this. I can also recommend another book, "Head First Design Patterns", which has a great section on the Factory patterns (if you like those "Head First" kinds of books.)

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