About XPConnect
Description
XPConnect is a technology that is used to link [XPCOM] and scripting languages like Javascript together.
Discussion
XPConnect allows JavaScript objects to transparently access and manipulate [XPCOM] objects. It also enables JavaScript objects to present [XPCOM] compliant interfaces to be called by [XPCOM] objects. A main goal is that objects communicating from either side of an [XPCOM] style interface should not generally need to know or care about the implementation language of the object on the other side of the interface.
XPConnect's primary reason for existence is to replace handwritten code used in places where native code needs to interact with JavaScript code. An example is the DOM module.
In order for XPConnect to properly function with [XPCOM] interfaces, it must be declared using XPIDL.
The XPConnect does not support the scripting of MS COM objects. It also does not support any interfaces that are not declared within XPIDL. While [XPCOM] objects are mainly supported, it does not support scripting of [XPCOM] objects that break conventions in [XPCOM]. E.g. non-standard return types, use of C++ default parameters, assumptions about the underlying C++ type of the object implementing a given interface, etc.
Relevant Resources
Links to Tutorials:
- In depth detail about XPConnect
- The XPConnect 'Components' Object Reference
- JavaScript Call Stack Dumper Reference
- XPCShell Reference
- JavaScript XPCOM Components Status
- Using XPCOM in JavaScript without leaking
- Dynamic Component Registration describes how to register your xpcom component so that it can be used from within Mozilla
Links to Examples:
- Simple XPConnect Sample
- XPConnect source code
- Document Object Model (DOM)
- Roadmap for XPCOM, XPConnect, XPTCall, and XPIDL
Links to FAQ:
Other Useful Links:
- XPCOM page
- XPIDL page
- typelibs
- xptcall
- Open bugs against XPConnect
- XPConnect runtime proposal
- XPConnect runtime interface thoughts
- Proposal for reflecting dynamic properties
- XPJS Components Proposal
Links to Newsgroups:
Links to IRC Channels:
Summarized By: Vanessa Miranda & Philip Vitorino