OS X に macports でインストールした mono で Graphics や Forms を使うための設定

OS X (10.5.6) に macports で mono をインストールしたはいいが、Windows.Forms や System.Drawing なアプリを動かすために設定が必要だったのにビックリしたので、備忘録をかねてメモ。

ためした環境

% mono -V
Mono JIT compiler version 2.0.1 (tarball)
Copyright (C) 2002-2008 Novell, Inc and Contributors. www.mono-project.com
	TLS:           normal
	GC:            Included Boehm (with typed GC)
	SIGSEGV:       normal
	Notification:  Thread + polling
	Architecture:  x86
	Disabled:      none

% port version
Version: 1.700

% port info mono
mono @2.0.1 (devel, lang, mono)
Variants:    darwin_9, universal

Mono is an effort to create an open source implementation of the .NET Development Framework including a C#
compiler.
Homepage:    http://www.go-mono.com/

Build Dependencies:   pkgconfig, gawk
Library Dependencies: gettext, glib2, libiconv, zlib, libgdiplus, XFree86
Platforms:            darwin
Maintainers:          mww@macports.org

設定しておかないとこういうエラーが出る

Unhandled Exception: System.TypeInitializationException: An exception was thrown by the type initializer for wizz.swimmy._081126.EntryPointForm ---> System.TypeInitializationException: An exception was thrown by the type initializer for System.Windows.Forms.WindowsFormsSynchronizationContext ---> System.TypeInitializationException: An exception was thrown by the type initializer for System.Windows.Forms.ThemeEngine ---> System.TypeInitializationException: An exception was thrown by the type initializer for System.Windows.Forms.ThemeWin32Classic ---> System.TypeInitializationException: An exception was thrown by the type initializer for System.Drawing.KnownColors ---> System.TypeInitializationException: An exception was thrown by the type initializer for System.Drawing.GDIPlus ---> System.DllNotFoundException: gdiplus.dll

必要だった設定

% cat ~/.mono/config
<configuration>
        <dllmap dll="gdiplus.dll" target="/opt/local/lib/libgdiplus.dylib"/>
</configuration>

要するに、libgdiplus がインストールされているだけでなく、gdiplus.dll の対応先(libgdiplus.dylib)がどこなのかを mono ランタイムに伝えてやる必要があるようだ。