wxPerl is a multi-platform windowing
API based on the wxWindows API for C++.
It allows developers to create perl applications that will run with little or no
modification on Windows, Motif, GTK and Mac GUI platforms.
And while there is an excellent set of documentation for the wxWindows toolset, wxPerl relies too heavily on its parent's documentation and provides little in the way of what perl programmers have come to rely on in terms of API references ,cookbook recipies and example scripts.
I believe that Wx will come to be a stronger and more reliable API that Win32::GUI, and am striving to document what I can. With that in mind, I'd like to present the first in an $n-part series of examples.
And while there is an excellent set of documentation for the wxWindows toolset, wxPerl relies too heavily on its parent's documentation and provides little in the way of what perl programmers have come to rely on in terms of API references ,cookbook recipies and example scripts.
I believe that Wx will come to be a stronger and more reliable API that Win32::GUI, and am striving to document what I can. With that in mind, I'd like to present the first in an $n-part series of examples.
This first one goes through the creation of one window with a simple
menu. There's a lot to absorb in wx, and I want to take things step-by-step to
make sure that they're presented as clearly as possible.
In the following example, there are three packages. One for the entire application (package MyApp), one for the window (package myFrame) and the main package. Most of the action occurs in myFrame, since that's where all of the controls will be added and where all of the methods are. MyApp acts like a wrapper around myFrame, but has its own methods and properties.
This example program will create a window, and a very simple menu -- all that can be done from it is exit. update Jouke has written a piece which appears on http://www.perl.com covering the same topic.
In the following example, there are three packages. One for the entire application (package MyApp), one for the window (package myFrame) and the main package. Most of the action occurs in myFrame, since that's where all of the controls will be added and where all of the methods are. MyApp acts like a wrapper around myFrame, but has its own methods and properties.
This example program will create a window, and a very simple menu -- all that can be done from it is exit. update Jouke has written a piece which appears on http://www.perl.com covering the same topic.
#!perl -w use Wx; ####################################### # # package MyApp; # # ####################################### use strict; use vars qw(@ISA); @ISA = qw(Wx::App); # the OnInit method is called sub OnInit { my($this) = @_; # # the constructor for our frame. # # although I chose to use 3 parameters in this construction, there +'s a # total of 7 parameters that may be used. # # wx::Frame->new (parent, # id, # title, # position, # size, # window style, # window name) # # the parent is a reference to a wxFrame which will be the paren +t of the # new frame. Setting this value to undef indicated this is a top +-level # frame in the application. # # The ID is an integer that gives the application an identity to + windows # # The title is just that -- what appears in the title bar of the + app. # # The optional parameters : # # The position is an anonymous array of 2 values indicating the +point # where the application till appear on screen. [0,0] is the uppe +r left # portion of the screen. To specify a default position, use [-1, +-1]. # If position is not specified, [-1,-1] is used # # Size determines the dimensions that the window will occupy in +. Again, # this is an array of 2 values, with [-1, -1] specifying a defau +lt size. # If size is not specified, [-1,-1] is used # # The window style lets the designer choose from a variety of op +tions # that will determine what options the frame will possess. # These can be used to keep users from minimizing or maximizing +an # application # The default is wxDEFAULT_FRAME_STYLE. The table below is from +wxWindows' # documentation. # # wxDEFAULT_FRAME_STYLE Defined as wxMINIMIZE_BOX | wxMAXIMIZ +E_BOX | wxRESIZE_BOX | wxSYSTEM_MENU | wxCAPTION. # wxICONIZE Display the frame iconized (minimized). Windows o +nly. # wxCAPTION Puts a caption on the frame. # wxMINIMIZE Identical to wxICONIZE. Windows only. # wxMINIMIZE_BOX Displays a minimize box on the frame. # wxMAXIMIZE Displays the frame maximized. Windows only. # wxMAXIMIZE_BOX Displays a maximize box on the frame. # wxSTAY_ON_TOP Stay on top of other windows. Windows only. # wxSYSTEM_MENU Displays a system menu. # wxSIMPLE_BORDER Displays no border or decorations. GTK and +Windows only. # wxRESIZE_BORDER Displays a resizeable border around the win +dow (Unix only). # wxFRAME_FLOAT_ON_PARENT Causes the frame to be above the pa +rent window in the z-order and not shown in the taskbar. Without this + style, frames are created as top-level windows that may be obscured +by the parent window, and frame titles are shown in the taskbar. Wind +ows and GTK. # wxFRAME_TOOL_WINDOW Causes a frame with a small titlebar to + be created; the frame title does not appear in the taskbar. Windows +only. my($frame) = MyFrame->new( undef, -1, "Hello World"); # # this property determines if the frame will be visible.. # Setting to 0 hides the frame. # $frame->Show(1); # # An optional method to let a wxApp distinguish the topmost wind +ow. # Apparently useful if there may be more than one top level wind +ow in # an application at a time for determining the behavior of modal + dialog # boxes # $this->SetTopWindow($frame); # if OnInit doesn't return true, the application exits immediately +. return 1; } ####################################### # # package MyFrame; # # ####################################### # # This package overrides Wx::Frame, and allows us to put controls # in the frame. # use strict; use vars qw(@ISA); @ISA = qw(Wx::Frame); # # most of these appear to be for constant declarations. # use Wx qw(:id :toolbar wxNullBitmap wxDefaultPosition wxDefaultSize wxDefaultPosition wxDefaultSize wxNullBitmap wxTB_VERTICAL wxSIZE wxTE_MULTILINE wxBITMAP_TYPE_BMP ); # # Wx::Events allows us to attach events to user's actions. # EVT_SIZE for resizing a window # EVT_MENU for selecting a menu item # EVT_COMBOBOX for selecting a combo box item # EVT_TOOL_ENTER for selecting toolbar items # use Wx::Event qw(EVT_SIZE EVT_MENU EVT_COMBOBOX EVT_UPDATE_UI EVT_TOOL_ENTER ); sub new { my( $class ) = shift; my( $this ) = $class->SUPER::new( @_ ); # allocate id numbers for controls. # This method appears a little strange, but it's a way to quickly +allocate # all IDs in one place. my( $ID_TOOLBAR, $ID_COMBO ) = ( 1 .. 100 ); # use the same method to allocate id numbers for menu items with e +vents. my( $IDM_FILE_OPEN, $IDM_FILE_CLOSE, ) = ( 10_000 .. 10_100 ); # create a new menu item. # a menu is attached to a menu bar, it is not the menu bar itself. # e.g. : A menu bar may have "File", "Edit" and "Tools" as options +, # each of which will display a menu. # # there is another way to display menus, but we'll get there later +. my $file_menu = Wx::Menu->new(); # # the next few lines create the entries that will be attached to $ +file_menu. # This process is called through Wx::Menu->Append (). # I have chosen to put the data that will create these items into # an array of array to automate the process of creation. # details of the structure mirror the parameters to Append and are + explained # below # # wxID_EXIT is a predefined id that is used for items which can tr +igger # an application's exit. Otherwise, it's appropriate to use ids th +at are # created in the application, like $IDM_FILE_OPEN is, below. my @file_menu_entries = ([$IDM_FILE_OPEN,"&Open\tCtrl-O","Open" ], ['-'], [wxID_EXIT, "E&xit\tCtrl-X", "Exit $0"] ); # # run through @file_menu_entries and add them. # Note that inside the loop we look to see if the first element +is # a single minus sign. # I chose to use this as a way to signal separators, which have +a # different method of being added to a menu. # foreach (@file_menu_entries) { if ($$_[0] eq '-') { # # Append a separator to the menu -- # A separator is a visual demarcation between groups of me +nu items # $file_menu->AppendSeparator(); } else { # # Append (as shown below, there are other ways to call it +) has 4 # possible parameters : # The unique id of the menu item being created # The text that will appear in the menu # The text that will appear in the status bar on mouse h +over # (optional) # Checkable -- if true, a checkmark will be toggled next + to the # menu item when selected (optional) # # Since I have no checkmarkable items, I chose to remove + it # entirely. This is probably not-so-hot in the long run. # $file_menu->Append ($$_[0],$$_[1],$$_[2]) } } # create the menubar that will contain the menu above. # the new method can take a style parameter, but it's only valid i +n GTK, so, # meh. # If it worked, the style parameter would allow menus to be dockab +le. # my $menubar = Wx::MenuBar->new(); # #attach a menu to the menubar. # $menubar->Append ($file_menu, '&File'); # # attach the menubar to the window. # $this->SetMenuBar ($menubar); # # this is the only event right now. # The EVT_MENU sets events called from clicking on menu items. # the parameters are # a reference to the frame; # the menu # EVT_MENU( $this, wxID_EXIT, sub {$_[0]->Close( 1 )} ); # # menu done, create tree control # return $this; } package main; my($app) = MyApp->new(); $app->MainLoop();
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