Class: Wx::DataObjectComposite

Inherits:

DataObject

Object
DataObject
Wx::DataObjectComposite

show all

Defined in:: lib/wx/doc/gen/data_object.rb

Overview

DataObjectComposite is the simplest DataObject derivation which may be used to support multiple formats.

It contains several DataObjectSimple objects and supports any format supported by at least one of them. Only one of these data objects is preferred (the first one if not explicitly changed by using the second parameter of #add) and its format determines the preferred format of the composite data object as well. See DataObject documentation for the reasons why you might prefer to use DataObject directly instead of DataObjectComposite for efficiency reasons. This example shows how a composite data object capable of storing either bitmaps or file names (presumably of bitmap files) can be initialized and used:

class MyDropTarget < Wx::DropTarget

    def initialize
      dataobj = Wx::DataObjectComposite.new
      dataobj.add(Wx::BitmapDataObject.new, true)
      dataobj.add(Wx::FileDataObject.new)
      set_data_object(dataobj)
    end
  
    def on_data(x, y, defaultDragResult)
      return Wx::DragNone unless get_data
  
      dataobj_comp = get_data_object
  
      format = dataobj_comp.get_received_format
      dataobj = dataobj_comp.get_object(format)
      case format.get_type
      when Wx::DataFormatId::DF_BITMAP
        # dataobj is Wx::BitmapDataObject

        ... use dataobj.get_bitmap ...

      when Wx::DataFormatId::DF_FILENAME
        # dataobj is Wx::FileDataObject

         ... use dataobj->GetFilenames() ...

      else
        Wx.log_error("unexpected data object format")
      end
  
      defaultDragResult
    end

  end

Category: Clipboard and Drag & Drop

Instance Method Summary collapse

#add(dataObject, preferred = false) ⇒ void

Adds the dataObject to the list of supported objects and it becomes the preferred object if preferred is true.
#get_object(format, dir = DataObject::Get) ⇒ Wx::DataObjectSimple (also: #object)

Returns the pointer to the object which supports the passed format for the specified direction.
#get_received_format ⇒ Wx::DataFormat (also: #received_format)

Report the format passed to the Wx::DataObject#set_data method.
#initialize ⇒ Wx::DataObjectComposite constructor

The default constructor.

Methods inherited from DataObject

#get_all_formats, #get_data_here, #get_data_size, #get_format_count, #get_preferred_format, #is_supported, #set_data

Constructor Details

#initialize ⇒ `Wx::DataObjectComposite`

The default constructor.

205	# File 'lib/wx/doc/gen/data_object.rb', line 205 def initialize; end

Instance Method Details

#add(dataObject, preferred = false) ⇒ `void`

This method returns an undefined value.

Adds the dataObject to the list of supported objects and it becomes the preferred object if preferred is true.

Parameters:

dataObject (Wx::DataObjectSimple)
preferred (Boolean) (defaults to: false)

211	# File 'lib/wx/doc/gen/data_object.rb', line 211 def add(dataObject, preferred=false) end

#get_object(format, dir = DataObject::Get) ⇒ `Wx::DataObjectSimple` Also known as: object

Returns the pointer to the object which supports the passed format for the specified direction.

NULL is returned if the specified format is not supported for this direction dir. The returned pointer is owned by Wx::DataObjectComposite itself and shouldn’t be deleted by caller.

Parameters:

format (Wx::DataFormat)
dir (Wx::DataObject::Direction) (defaults to: DataObject::Get)

Returns:

(Wx::DataObjectSimple)

226	# File 'lib/wx/doc/gen/data_object.rb', line 226 def get_object(format, dir=DataObject::Get) end

#get_received_format ⇒ `Wx::DataFormat` Also known as: received_format

Report the format passed to the Wx::DataObject#set_data method.

This should be the format of the data object within the composite that received data from the clipboard or the DnD operation. You can use this method to find out what kind of data object was received.