快速入门：应用程序
A command is an action that is presented in Cinema 4D 's user interface. The command can be invoked by pressing the button in the interface or calling CallCommand() with the command ID.
A custom command is created by implementing a CommandData based class. CommandData::Execute() receives a pointer to the currently active BaseDocument .
另请参阅 一般插件信息手册 and Command Utility Manual .
// This example shows the most simple version of a CommandData plugin.A custom command plugin must be registered with RegisterCommandPlugin() . The function must be called in the context of PluginStart() .
另请参阅 插件函数手册 .
// This example shows how to use a "Register" function to register a plugin.// registers a CommandData plugin RegisterCommandPlugin (pluginID, "Example Command" _s, 0, nullptr , "" _s, ExampleCommand::Alloc());
GeDialog is the base class for custom dialog windows. A custom window is created by implementing a GeDialog based class.
见 GeDialog 手册 .
// This example shows the most simple implementation of a GeDialog based window. class ExampleDialog : public GeDialog { INSTANCEOF (ExampleDialog, GeDialog ) public : Bool CreateLayout () { SetTitle ( "Example Dialog" _s); return true ; } };A dialog window can be displayed modal/synchronously (blocking) or non-modal/asynchronously. Such an asynchronous dialog instance must be stored in memory. It is typically stored as a member of a CommandData plugin. The CommandData plugin can be used to open and close the dialog. CommandData::RestoreLayout() must be implemented to handle the dialog correctly in a layout.
// This example shows a CommandData plugin that hosts and opens a GeDialog based window. class ExampleCommand : public CommandData { INSTANCEOF (ExampleCommand, CommandData ) private : ExampleDialog _dialog; public : Bool Execute ( BaseDocument * doc, GeDialog * parentManager) { if (_dialog.IsOpen() == false ) { // open dialog window _dialog.Open( DLG_TYPE::ASYNC , g_exampleDialogID, -1, -1, 400, 400); } else { // close dialog window _dialog.Close(); } return true ; }; Bool RestoreLayout ( void * secret) { return _dialog.RestoreLayout(g_exampleDialogID, 0, secret); }; static ExampleCommand* Alloc() { return NewObjClear(ExampleCommand); } };The layout is defined with groups that contain various GUI gadgets. It is possible to define the layout by implementing GeDialog::CreateLayout() . It is also possible to define the layout in a layout file.
// This example shows how to add basic dialog gadgets // to the layout and how to define the default value. Bool CreateLayout() { SetTitle( "Example Dialog" _s);// group with two columns GroupBegin(100, BFH_SCALEFIT , 2, 0, "" _s, 0, 0, 300); AddEditNumber(g_numberID, BFH_SCALEFIT , 0, 10); AddButton(g_buttonID, BFH_SCALEFIT , 0, 10, "Increase" _s); GroupEnd(); return true ; } Bool InitValues() { // set the value for the edit number gadget SetInt32(g_numberID, 123); return true ; }
A user can interact with the gadgets displayed in the dialog. The dialog can react when a value was changed or when a button was pressed. In such a case GeDialog::Command() will be called.
见 交互 and Gadget Values .
// This example shows how to implement GeDialog::Command() to define the user interaction. Bool Command( Int32 id , const BaseContainer & msg) { switch ( id ) { // the number value was changed case (g_numberID): { ApplicationOutput ( "Value changed" );// get the value Int32 value; if (GetInt32(g_numberID, value)) { // print value const String valueStr = String::IntToString (value); ApplicationOutput ( "Value: " + valueStr); } break ; } // the button was pressed case (g_buttonID): { ApplicationOutput ( "The button was pressed" );
// get value Int32 value; if (GetInt32(g_numberID, value)) { // increase value value = value + 1; // store increased value SetInt32(g_numberID, value); } break ; } } return true ; }
Files can simply be read using file streams. File names can be handled using the classic Filename class or the maxon::Url class.
见 Filename Manual , Url Manual and InputStream Manual .
// This example shows a simple function to load text from a file. String LoadTextFromFile( const Filename & file) { iferr_scope_handler { err.DiagOutput(); err.DbgStop(); return "" _s; };// construct maxon::Url const maxon::Url url = MaxonConvert (file, MAXONCONVERTMODE::NONE );
// check if this is a file if (url.IoDetect() != maxon::IODETECT::FILE ) iferr_throw (maxon::IoError( MAXON_SOURCE_LOCATION , url, "File not found." _s));
// open input stream and get file size const maxon::InputStreamRef inputStream = url.OpenInputStream() iferr_return ; const maxon::Int length = inputStream.GetStreamLength() iferr_return ; maxon::BaseArray<maxon::Char> data; data. Resize (length) iferr_return ; inputStream.Read(data) iferr_return ;
// convert to String return maxon::String { data }; }
This function could be used in a dialog like this:
// This example shows the implementation of a simple dialog window // that offers a button to select and load a text file. The content // of that text file is displayed in the dialog window text field. Bool CreateLayout() { SetTitle( "Example Dialog" _s); GroupBegin(100, BFH_SCALEFIT , 2, 0, "" _s, 0, 0, 300); const Int32 style = DR_MULTILINE_WORDWRAP ; AddMultiLineEditText(g_textID, BFH_SCALEFIT | BFV_TOP , 0, 200, style); AddButton(g_buttonID, BFH_SCALEFIT | BFV_TOP , 0, 10, "Load Text File" _s); GroupEnd(); return true ; } Bool Command( Int32 id , const BaseContainer & msg) { switch ( id ) { // the button was pressed case (g_buttonID): { ApplicationOutput ( "The button was pressed" );// select file Filename selectedFile; if (selectedFile. FileSelect ( FILESELECTTYPE::ANYTHING , FILESELECT::LOAD , "Load File" _s) == false ) return true ; const String loadedText = LoadTextFromFile(selectedFile); SetString(g_textID, loadedText); break ; } } return true ; }
