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diff --git a/Mac/Demo/example2.html b/Mac/Demo/example2.html deleted file mode 100644 index 2c3cd2272f..0000000000 --- a/Mac/Demo/example2.html +++ /dev/null @@ -1,162 +0,0 @@ -<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> |