I am trying to learn how to write firefox extensions. I download an HelloWorld example from here but I can't figure out how to register it.
I found my profiles extension folder (Easy since I use the latest Firefox version) but couldn't really understand what is this "Pointer file" that I need to create (tried a shortcut but it didn't work).
What is this "Pointer File"?
How can I register it correctly?
I am using Win 7 if matters.
Thank You.
You have to create a file in the extensions folder with the ID of the add-on as name (e.g. helloworld#mozilla.doslash.org). This file should contain only one line which is the absolute path to the folder where the add-on is contained (e.g. C:\\my\path\to\addon (or however windows paths look like)).
The add-on name is located inside of the install.rdf file. Usually, it's a GUID string, but for the demo it will look like an email address.
The filename will need to match that exactly and be free of any .txt extensions, so be careful your text editor doesn't automatically give it an extension.
Related
I am trying to open a .chm file.
I downloaded the source, extracted it, and double clicked on Waffle.chm and clicked "Open" but no matter what element in the chm file I click, I get the message:
Navigation to the webpage was canceled.
What you can try:
Retype the address.
What's going on here?
Summary
Microsoft Security Updates 896358 & 840315 block display of CHM file contents when opened from a network drive (or a UNC path). This is Windows' attempt to stop attack vectors for viruses/malware from infecting your computer and has blocked out the .chm file that draw data over the "InfoTech" protocol, which this chm file uses.
Microsoft's summary of the problem: http://support.microsoft.com/kb/896054
Solutions
If you are using Windows Server 2008, Windows 7, windows has created a quick fix. Right click the chm file, and you will get the "yourfile.chm Properties" dialog box, at the bottom, a button called "Unblock" appears. Click Unblock and press OK, and try to open the chm file again, it works correctly. This option is not available for earlier versions of Windows before WindowsXP (SP3).
Solve the problem by moving your chm file OFF the network drive. You may be unaware you are using a network drive, double check now: Right click your .chm file, click properties and look at the "location" field. If it starts with two backslashes like this: \\epicserver\blah\, then you are using a networked drive. So to fix it, Copy the chm file, and paste it into a local drive, like C:\ or E:. Then try to reopen the chm file, windows does not freak out.
Last resort, if you can't copy/move the file off the networked drive. If you must open it where it sits, and you are using a lesser version of windows like XP, Vista, ME or other, you will have to manually tell Windows not to freak out over this .chm file. HHReg (HTML Help Registration Utility) Utility Automates this Task. Basically you download the HHReg utility, load your .chm file, press OK, and it will create the necessary registry keys to tell Windows not to block it. For more info: http://www.winhelponline.com/blog/fix-cannot-view-chm-files-network-xp-2003-vista/
Windows 8 or 10? --> Upgrade to Windows XP.
"unblocking" the file fixes the problem. Screenshot:
Win 8 x64:
just move it to another folder or rename your folder (in my case: my folder was "c#").
avoid to use symbol on folder name. name it with letter.
done.
In addition to Eric Leschinski's answer, and because this is stackoverflow, a programmatical solution:
Windows uses hidden file forks to mark content as "downloaded". Truncating these unblocks the file. The name of the stream used for CHM's is "Zone.Identifier". One can access streams by appending :streamname when opening the file. (keep backups the first time, in case your RTL messes that up!)
In Delphi it would look like this:
var f : file;
begin
writeln('unblocking ',s);
assignfile(f,'some.chm:Zone.Identifier');
rewrite(f,1);
truncate(f);
closefile(f);
end;
I'm told that on non forked filesystems (like FAT32) there are hidden files, but I haven't gotten to the bottom of that yet.
P.s. Delphi's DeleteFile() should also recognize forks.
The definitive solution is to allow the InfoTech protocol to work in the intranet zone.
Add the following value to the registry and the problem should be solved:
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\HTMLHelp\1.x\ItssRestrictions]
"MaxAllowedZone"=dword:00000001
More info here: http://support.microsoft.com/kb/896054
Go to Start
Type regsvr32 hhctrl.ocx
You should get a success message like:
" DllRegisterServer in hhctrl.ocx succeeded "
Now try to open your CHM file again.
other way is to use different third party software. This link shows more third party software to view chm files...
I tried with SumatraPDF and it work fine.
I fixed this programmatically in my software, using C++ Builder.
Before I assign the CHM help file, Application->HelpFile = HelpFileName, I check to see if it contains the "Zone.Identifier" stream, and when it does, I simply remove it.
String ZIStream(HelpFileName + ":Zone.Identifier") ;
if (FileExists(ZIStream))
{ DeleteFile(ZIStream) ; }
There are apparently different levels of authentication. Most articles I read tell you to set the MaxAllowedZone to '1' which means that local machine zone and intranet zone are allowed but '4' allows access for 'all' zones.
For more info, read this article:
https://support.microsoft.com/en-us/kb/892675
This is how my registry looks (I wasn't sure it would work with the wild cards but it seems to work for me):
Windows Registry Editor Version 5.00
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\HTMLHelp]
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\HTMLHelp\1.x]
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\HTMLHelp\1.x\ItssRestrictions]
"MaxAllowedZone"=dword:00000004
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\HTMLHelp\1.x\ItssRestrictions]
"UrlAllowList"="\\\\<network_path_root>;\\\\<network_path_root>\*;\\ies-inc.local;http://www.*;http://*;https://www.*;https://*;"
As an additional note, weirdly the "UrlAllowList" key was required to make this work on another PC but not my test one. It's probably not required at all but when I added it, it fixed the problem. The user may have not closed the original file or something like that. So just a consideration. I suggest try the least and test it, then add if needed. Once you confirm, you can deploy if needed. Good Luck!
Edit: P.S. Another method that worked was mapping the path to the network locally by using mklink /d (symbolic linking in Windows 7 or newer) but mapping a network drive letter (Z: for testing) did not work. Just food for thought and I did not have to 'Unblock' any files. Also the accepted 'Solution' did not resolve the issue for me.
Moving to local folder is the quickest solution, nothing else worked for me esp because I was not admin on my system (can't edit registery etc), which is a typical case in a work environment.
Create a folder in C:\help drive, lets call it help and copy the files there and open.
Do not copy to mydocuments or anywhere else, those locations are usually on network drive in office setup and will not work.
This is only under windows env.
As I know windows os identifies associated application of a particular file by file extension.
Like wise each file (binary) starting with corresponding symbols ("starting symbols"). For an example .JPG starts with ÿØÿà. Let say I open this .JPG file in a Hex editor or a Text editor and then I change that starting symbols into another file type. for an example I can change ÿØÿà to .Eߣ (.mkv). So when I double click on the .JPG the Windows Photo Viewer says there are some errors or similar message. So I need to get some information about the application that tries to open that kind of a file. If I can, I need to open that file using the application that associated with "starting symbols".
Briefly when I open .JPG I need to open a default video player .mkv files. But It may not work for this example. Because I changed only the "starting symbols" of my .JPG.
Please give me any idea to do this.
Thanks!
When you encrypt the file, give it a new extension. e.g. Picture.jpg becomes Picture.encrypted-jpg. You then register as the handler for encrypted-jpg, decrypt the file, then launch the normal jpg handler.
When the shell is asked to perform a verb on a file, the shell does not use the contents of the file to determine which app to pass it to. The file extension is what determines how the file will be treated.
You wish to use the contents of the file to influence which app processes a shell verb. In order to do so you would need to create a launcher app that reads the file header and then decides which app to pass the file on to. You would assign your launcher app as the handler app for all file extensions that you were interested in.
Although you could do this, it would be much easier just to set the file extension appropriately.
The proper way to do this sort of thing is to replace the files with reparse points.
The downside is that this involves writing a file system filter driver, i.e., an operating system extension, which is a whole level of trouble above and beyond ordinary application programming. (Since Windows already does file encryption, I doubt it would be worth the effort.)
I downloaded this Firefox sample extension from mozilla.org, I modified the file install.rdf and changed maxVersion value to 3.6.10 (also tried 3.6.*, 100 and *) and I added a new string with name "hello world" and the value is the path where the folder of the sample extension is to HKCU (also tried HKLM)/Software/Mozilla/Firefox/Extensions/ into the registry.
I start Firefox, go to Tools > Addons, and it says it needs to restart, I restart and go there again and the plugin appears but says "Not compatible with Firefox 3.6.10", and every button appears disabled. Also removing the registry key and folder doesn't uninstall it.
Is there something else I have to change to use the hello world sample in Firefox 3.6.10?
Update 2018
This sample extension was created in 2000s and Firefox switched to a radically different extension system called "Web Extensions" in 2017. The old extensions will not work in the current versions of Firefox and have to be rewritten completely.
The easiest way to start developing an extension is putting a "pointer" file in the extensions folder in the profile directory. I wouldn't touch the registry method until the deployment moment.
Thanks for reminding me to update the example extension. Updated it now.
Basically, the best way to use an extension is to package the addon in .xpi format. Then you just have to open this addon with Firefox. Note:To make an .xpi , take all the contents of helloworld like content,locale,skin,install.rdf,chrome.manifest etc and try to zip it but change the extension to .xpi instead of .zip. Otherwise u can just rename ur helloworld folder to helloworld#xyz.com and then copy this folder into C:\Users\"OS user name"\AppData\Roaming\Mozilla\Firefox\Profiles\h31hcfq9.default\extensions and then restart ur browser. Also, it would be best to learn about addon development with this Basic tutorial on addon development
The procedure to create sample firefox extension can be found on this link. This tutorial explains how to create a Firefox extension to find all links in the current web page, highlight those which have a target attribute and alert you how many links it found.
I have both InDesign CS2 and CS3 installed. Both use files with .indd extension. How does Windows know which icon to use? It uses correct icons i.e. CS2 files have cs2 icon and CS3 files have CS3 icon.
How does Windows know how to do this?
And how can I extract or use this version-detection system in my programs?
Edit:
Thank you for your shell-extension-icon-handler answers. Something new to me. But is there any way I could connect to IconHandler that InDesign provides and use it to detect version of the InDesign file?
You need to write an Icon Handler shell extension. See the MSDN documentation for IExtractIcon. The basic mechanism is that you create a shell extension and register the icon handler for the file type you want (look in HKEY_CLASSES_ROOT/.indd) and then the shell loads your handler, passes the file information and requests an icon in return. There's also the IExtractImage method if you want to provide a thumbnail bitmap rather than just an icon.
Note that you need to be especially careful writing shell extension handlers as any memory leaks or crashes can nuke the explorer and any other applications that display a file open/save dialog.
For some files it's HKEY_CLASSES_ROOT\<file extension here>\DefaultIcon registry entry, but most files map to a more friendly name, e.g. .pdf\(Default) -> AcroExch.Document (if Adobe Reader is installed).
In that case you have to go along the registry to AcroExch.Document and see that either
DefaultIcon is right there or
AcroExch.Document\CLSID\(Default) is some GUID. Then, follow HKEY_CLASSES_ROOT\CLSID\<insert that guid here> and you'll notice that this key contains DefaultIcon
... and DefaultIcon is where the icon is loaded from.
Hope that was clear enough ;). I don't know about your special case but there should be a distinction in the registry.
It almost certainly installs a shell icon extension handler. Writing your own and knowing how to detect the version in a file format that isn't documented well or at all is quite tricky.
Problem: I have to support users who need to edit web pages. Some of these web pages exist only as textarea controls. Fortunately, there is a firefox plugin that allows the user to open the textarea in a default text editor. Unfortunately, this plugin requires you to point to the EXE file of the text editor you want to invoke.
This is a reasonable requirement, but ##$%^ Microsoft Expression Web is one of those applications whose shortcut .lnk file does not appear to point to a real EXE file. If there is an EXE file somewhere, it's hidden.
Question:
How can I locate the actual EXE file so people can configure Microsoft Expression web to be their editor of choice?
Update: I should have emphasized that I was looking for a way to automate this via script or batch file (hence the SO posting, in case anyone's "not-programming-related" spidey sense was tingling).
I found my executable in the following location:
C:\Program Files\Microsoft Expression\Web Designer\EXPRWD.EXE
I'm not sure if that gives you what you need, but you can always have your users (or programmatically) search for EXPRWD.EXE and go from there.