<center><b><font size=+2>Python Component Sample</font></b>

<p>

<br>

Last modified

<script>

document.write(document.lastModified);

</script>

</center>

<p>XPConnect allows JavaScript

to transparantly access and manipulate XPCOM objects;

<p>Big Deal, I hear you say! But it also works for Python!!!

<p>

This sample demonstrates accessing a XPCOM object through XPConnect.

The JavaScript executed when this page loads creates an instance

of the Python object by

using the <tt>Components</tt> object, then accesses it through

the <a href="py_test_component.idl">nsISample</a> interface by calling <tt>QueryInterface</tt>:

<br>

<pre>

netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect");

var sample = Components.classes["component://mozilla/sample/sample-world"].createInstance();

sample = sample.QueryInterface(Components.interfaces.nsISample);

</pre>

<p>

The buttons on the form are connected to JavaScript event handlers which

call the methods defined in Python

<p><b><a name="Compiling">Compiling the idl</b>

<p>The XPIDL compiler (xpidl on Unix, xpidl.exe on Windows, and a CodeWarrior plugin on Mac)

is compiled at build time (except on Mac) thus

you will have to build mozilla in order to test this out. If you

have already built mozilla then the compiler will be located at <tt>mozilla\dist\WIN32_D.OBJ\bin\xpidl.exe</tt>.

<p>Once you have the XPIDL compiler enter the following command at your

prompt:

<br><tt>D:\whereever\xpcom\test\test_component>d:\mozilla\dist\WIN32_D.OBJ\bin\xpidl -I

d:\mozilla\dist\idl -m typelib py_test_component.idl</tt>. You must then copy the generated .xpt file

to the mozilla component directory.

<p>The <tt>-I d:\mozilla\dist\idl</tt> points the compiler to the folder

containing the other idl files, needed because nsISample.idl inherits from

nsISupports.idl. The <tt>-m typelib</tt> instruction tells the compiler

to build the .XPT typelib file.</tt>.

<p>

For more information on compilation see the <a href="http://www.mozilla.org/scriptable/xpidl/">xpidl

compiler page</a>.

<p><b>Running the sample</b>

<p><b>NOTE: This doesnt work for me - I get an access denied error using XPConnect!</b>

<p>Using Mozilla, load this file. Pay attention

to the console when clicking "write".

<script>

netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect");

var sample = Components.classes["Python.TestComponent"].createInstance();

sample = sample.QueryInterface(Components.interfaces.nsIPythonTestInterface);

dump("sample = " + sample + "\n");

function get()

{

var field = document.getElementById('Value');

field.value = sample.str_value;

}

function set()

{

var field = document.getElementById('Value');

sample.str_value = field.value;

}

function poke()

{

var field = document.getElementById('Value');

sample.poke(field.value);

}

function write()

{

sample.writeValue("here is what I'm writing: ");

}

</script>

<p>

<form name="form">

<input type="button" value="Get" onclick="get();">

<input type="button" value="Set" onclick="set();">

<input type="button" value="Poke" onclick="poke();">

<input type="text" id="Value">

<input type="button" value="Write" onclick="write();">

<form>

<hr>

<p>

JavaScript and form source:

<pre>

&lt;script&gt;

netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect");

var sample = Components.classes["component://Python.TestComponent"].createInstance();

sample = sample.QueryInterface(Components.interfaces.nsIPythonTestInterface);

dump("sample = " + sample + "\n");

function get()

{

var field = document.getElementById('Value');

field.value = sample.str_value;

}

function set()

{

var field = document.getElementById('Value');

sample.str_value = field.value;

}

function poke()

{

var field = document.getElementById('Value');

sample.poke(field.value);

}

function write()

{

sample.writeValue("here is what I'm writing: ");

}

&lt;/script&gt;

&lt;form name=&quot;form&quot;&gt;

&lt;input type=&quot;button&quot; value=&quot;Get&quot; onclick=&quot;get();&quot;&gt;

&lt;input type=&quot;button&quot; value=&quot;Set&quot; onclick=&quot;set();&quot;&gt;

&lt;input type=&quot;button&quot; value=&quot;Poke&quot; onclick=&quot;poke();&quot;&gt;

&lt;input type=&quot;text&quot; id=&quot;Value&quot;&gt;

&lt;input type=&quot;button&quot; value=&quot;Write&quot; onclick=&quot;write();&quot;&gt;

&lt;form>

</pre>