symbian-qemu-0.9.1-12/python-2.6.1/Mac/Demo/example2.html
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+<HTML><HEAD><TITLE>Using python to create Macintosh applications, part two</TITLE></HEAD>
+<BODY>
+<H1>Using python to create Macintosh applications, part two</H1>
+<HR>
+
+In this document we rewrite the application of the <A
+HREF="example1.html">previous example</A> to use modeless dialogs. We
+will use an application framework, and we will have a look at creating
+applets, standalone applications written in Python.  The <A
+HREF="example2/dnslookup-2.py">source code</A> and 
+<A HREF="example2/dnslookup-2.rsrc">resource file</A> are available in the folder 
+<A HREF="example2">example2</A>. <p>
+
+Again, we start with ResEdit to create our dialogs. Not only do we
+want a main dialog this time but also an "About" dialog.  This example is less
+than complete since we do not provide a <A NAME="bundle">BNDL resource</A> 
+and related stuff that an application cannot be without. We are able to do this
+when building a python applet since BuildApplet will substitute default resources
+for BNDL, etc. when none are supplied (<A HREF="#no-bundle">See below</A>.)
+"Inside Mac" or various
+books on Macintosh programming will help here. Also, you can refer to
+the resource files provided in the Python source distribution for some
+of the python-specific points of BNDL programming: the
+"appletbundle.rsrc" file is what is used for creating applets if you
+don't provide your own resource file. <p>
+
+When creating your own BNDL resouorces, keep in mind that the Finder gets 
+confused if you have more than one application with the same signature. This may be due 
+to some incorrectness on the side of "BuildApplet", I am not sure.  There is one 
+case when you definitely need a unique signature: when you create an applet that 
+has its own data files and you want the user to be able to start your
+applet by double-clicking one of the datafiles. <p>
+
+Let's have a look at dnslookup-2.rsrc, our resource file. Dialog 512 is the
+main window which has one button (Lookup), two labels and
+two text entry areas, one of which is used for output only. The "Quit"
+button has disappeared, because its function is handled by a menu choice.  Here's
+what it will look like at run time:<p>
+<div align=center>
+<img width=324 height=205 src="example2/dnslookup-2.gif" alt="dialog image">
+</div>
+<p>
+
+<H2>A modeless dialog application using FrameWork</H2>
+
+On to the source code in <A
+HREF="example2/dnslookup-2.py">dnslookup-2.py</A>.  The
+start is similar to our previous example program <A
+HREF="example1/dnslookup-1.py">dnslookup-1.py</A>, with
+one extra module being imported. To make life more simple we will use
+the <CODE>FrameWork</CODE> module, a nifty piece of code that handles
+all the gory Mac details of event loop programming, menubar
+installation and all the other code that is the same for every Mac
+program in the world.  Like most standard modules, FrameWork will run
+some sample test code when you invoke it as a main program, so try it
+now. It will create a menu bar with an Apple menu with the about box
+and a "File" menu with some pythonesque choices (which do nothing
+interesting, by the way) and a "Quit" command that works. <p>
+
+<BLOCKQUOTE>
+If you have not used <code>FrameWork</code> before you may want to
+first take a look at the <A HREF="textedit.html">Pathetic EDitor</A>
+example, which builds a minimal text editor using FrameWork and TextEdit.
+On the other hand: we don't use many features of FrameWork, so you could
+also continue with this document. 
+</BLOCKQUOTE>
+
+After the imports we get the definitions of resource-IDs in our
+resource file, slightly changed from the previous version of our
+program. The main program is also
+similar to our previous version, with one important exception: we
+first check to see whether our resource is available before opening
+the resource file. Why is this? Because later, when we will have
+converted the script to an applet, our resources will be available in
+the applet file and we don't need the separate resource file
+anymore. <p>
+
+Next comes the definition of our main class,
+<CODE>DNSLookup</CODE>, which inherits
+<CODE>FrameWork.Application</CODE>. The Application class handles the
+menu bar and the main event loop and event dispatching. In the
+<CODE>__init__</CODE> routine we first let the base class initialize
+itself, then we create our modeless dialog and finally we jump into
+the main loop. The main loop continues until we call <CODE>self._quit</CODE>,
+which we will do when the user selects "Quit". When we create
+the instance of <CODE>MyDialog</CODE> (which inherits
+<CODE>DialogWindow</CODE>, which inherits <CODE>Window</CODE>) we pass
+a reference to the application object, this reference is used to tell
+Application about our new window.  This enables the event loop to keep
+track of all windows and dispatch things like update events and mouse
+clicks. <p>
+
+The <CODE>makeusermenus()</CODE> method (which is called sometime
+during the Application <CODE>__init__</CODE> routine) creates a File
+menu with a Quit command (shortcut command-Q), which will callback to
+our quit() method. <CODE>Quit()</CODE>, in turn, calls <CODE>_quit</CODE> which
+causes the mainloop to terminate at a convenient time. <p>
+
+Application provides a standard about box, but we override this by
+providing our own <CODE>do_about()</CODE> method which shows an about
+box from a resource as a modal dialog. This piece of code should look
+familiar to you from the previous example program. That do_about is
+called when the user selects About from the Apple menu is, again,
+taken care of by the __init__ routine of Application. <p>
+
+The <CODE>MyDialog</CODE> class is the container for our main
+window. Initialization is again done by first calling the base class
+<CODE>__init__</CODE> function and finally setting the local variable
+"parent." <p>
+
+<CODE>Do_itemhit()</CODE> is called when an item is selected in this
+dialog by the user. We are passed the item number (and the original
+event structure, which we normally ignore). The code is similar to the
+main loop of our previous example program: a switch depending on the
+item selected.  <CODE>Dnslookup()</CODE> is quite similar to our previous 
+example. <p>
+
+<H2><IMG SRC="html.icons/mkapplet.gif"><A NAME="applets">Creating applets</A></H2>
+
+Now let us try to turn the python script into an applet, a standalone
+application. This will <em>not</em> work if you have the "classic 68k"
+Python distribution, only if you have the cfm68k or PPC distribution.
+
+<blockquote>
+Actually, "standalone" is probably not the correct term here, since an
+applet does still depend on a lot of the python environment: the
+PythonCore shared library, the Python Preferences file, the python Lib
+folder and any other modules that the main module depends on. It is
+possible to get rid of all these dependencies and create true standalone
+applications in Python, but this is a bit difficult. See <a href="freezing.html">
+Standalone Applications in Python</a> for details. For this
+document, by standalone we mean here that
+the script has the look-and-feel of an application, including the
+ability to have its own document types, be droppable, etc.
+</blockquote>
+
+The easiest way to create an applet is to take your source file and
+drop it onto "BuildApplet", located in the Python home
+folder. This will create an applet with the same name as your python
+source with the ".py" stripped. Also, if a resource file with the same
+name as your source but with ".rsrc" extension is available the
+resources from that file will be copied to your applet too. If there
+is no resource file for your script a set of default resources will be
+used, and the applet will have the default creator 'Pyt0'. The latter
+also happens if you do have a resource file but without the BNDL
+combo. <A NAME="no-bundle">Actually</A>, as in the present example.
+<p>
+
+If you need slightly more control over the BuildApplet process you can
+double-click it, and you will get dialogs for source and
+destination of the applet. The rest of the process, including locating
+the resource file, remains the same. <p>
+
+Note that though our example application completely bypasses the
+normal python user interface this is by no means necessary. Any python
+script can be turned into an applet, and all the usual features of the
+interpreter still work. <p>
+
+That's all for this example, you may now return to the <A HREF="index.html">
+table of contents</A> to pick another topic. <p>
+</BODY>
+</HTML>