Problem

Solution

###########################################################################################################
#
# The PathList widget is a component that collects a list of paths. It appears as a normal list but when
# the user double clicks an item, an edit field and a browse button appear on the item to let the user edit 
# or select a path thorugh a dialog box. An item can be deleted using the Del button or emptying its
# content. An item can be selected also with the arrows keys and edited pressing the return key. 
#
# Author: Marco Frailis
#
###########################################################################################################


class PathList < FXList

  include Responder

  def initialize(composite,tgt = nil, sel = 0, opts = LIST_NORMAL,xpos = 0,ypos = 0,pwidth = 0,pheight = 0)

    super(composite, tgt,sel,opts,xpos,ypos,pwidth,pheight)

    identifier :ID_DBCLICK, :ID_EDITFIELD, :ID_BRWBUTTON

    FXMAPFUNC(SEL_DOUBLECLICKED, 0, 'onCmdDoubleClicked')
    FXMAPFUNC(SEL_KEYPRESS, PathList::ID_EDITFIELD, 'onCmdEditKeyPress')
    FXMAPFUNC(SEL_FOCUSOUT, PathList::ID_EDITFIELD, 'onCmdFocusOut')
    FXMAPFUNC(SEL_COMMAND, PathList::ID_BRWBUTTON, 'onCmdBrowse')
    FXMAPFUNC(SEL_KEYPRESS, 0, 'onKeyPress')   
    FXMAPFUNC(SEL_CHANGED, FXWindow::ID_VSCROLLED, 'onVScrollerDragged')
    
    #An horizontal frame which contains an edit field and a browse button.
    #Note that it belongs to the composite passed in the constructor parameters
    @editBox=FXHorizontalFrame.new(composite,FRAME_LINE|LAYOUT_FIX_X|LAYOUT_FIX_Y|LAYOUT_FIX_WIDTH,0,0,300,100,0,0,0,0)
    @editBox.setVSpacing(0)
    @editBox.setHSpacing(0)

    #A textfield to insert or edit a path into the list
    @textField=FXTextField.new(@editBox,10,self,ID_EDITFIELD,LAYOUT_FILL_X|LAYOUT_FILL_Y)
    #A button opening a dialog to select a particular directory
    @brwButton=FXButton.new(@editBox,"...",nil,self,ID_BRWBUTTON,BUTTON_NORMAL|LAYOUT_FILL_Y)
    #The last item in the list is always empty (contains a space character)
    appendItem(" ")

    @lastItem = 0
    @selectedItem = nil
    
    #The edit box is hidden when no action is performed on the list
    @editBox.hide

    #This variable becomes true when the user press the return key
    @returnPressed = false
  end

  #This method is called when the user double clicks a list item
  def onCmdDoubleClicked(sender,sel,ptr)
    scrollbar = verticalScrollBar
    @selectedItem = getCurrentItem
    #if the item selected is the last, than it's empty
    if (@selectedItem == @lastItem)
      @textField.text = ""
    #otherwise the text field is filled with the path contained into the item
    else 
      @textField.text = getItemText(@selectedItem)
    end

    #The edit box is resized and positioned to completely overlap the list item selected
    width = (scrollbar.shown) ? getWidth-scrollbar.getWidth : getWidth
    height = getItemHeight(@selectedItem)
    @editBox.position(x,y+(height*@selectedItem)-scrollbar.position,width,height)
    #The edit box is shown 
    @editBox.raiseWindow()
    @editBox.show
    @textField.setFocus
    @textField.onCmdCursorEnd(nil,0,nil)
  end

  #This method is called when the user press a key.
  #If the edit box is active and the user press return
  #the edit box is hidden loosing its focus (see the foolowing method) 
  #otherwise it returns false so that the onKeyPress method is called
  def onCmdEditKeyPress(sender,sel,ptr)
    event = ptr
    if (event.code == KEY_Return) && (@textField.hasFocus)
      @returnPressed = true
      @editBox.hide
    else
      return false
    end
  end

  #This method "in practice" is called when the edit box looses its focus
  #It sets a list item text to the path in the edit box. If the edit box
  #is empty, the item is removed
  def onCmdFocusOut(sender,sel,ptr)
    posx,posy,z = parent.getCursorPosition
    if (parent.getChildAt(posx,posy) != @editBox) || @returnPressed
      if (@textField.text == "")
        setCurrentItem = @selectedItem
        removeElement
      else
        setItemText(@selectedItem,@textField.text)
        @textField.text=""
        if (@selectedItem == @lastItem)
          #The last item contains only a space
          appendItem(" ")
          @lastItem += 1
        end
      end
        @returnPressed = false
        @editBox.hide
    end
  end

  #This method is called when the user press the small browse button in the
  # edit box. It raises a directory dialog box.
  def onCmdBrowse(sender,sel,ptr)
    dirDiag = FXDirDialog.new(self,"Path selection")
    if (@textField.text != "")
      dirDiag.setDirectory(@textField.text)
      dirDiag.forceRefresh()
    end
    if (dirDiag.execute != 0)
      @textField.text = dirDiag.getDirectory
      @textField.onCmdCursorEnd(nil,0,nil)
    end
    @textField.setFocus
  end

  #If the key pressed by the user is a delete. the selected item
  #is deleted
  def onKeyPress(sender,sel,ptr)
    event = ptr
    if (event.code == KEY_Delete)
      i = 0
      while (i < getNumItems-1) do
        if isItemSelected(i)
          setCurrentItem(i)
          removeElement
        else
          i += 1
        end
      end
    else
      super
    end
  end

  #If the edit box is visible and the user scrolls the list
  #it's position is adjusted to remain over the selected item
  def onVScrollerDragged(sender,sel,ptr)
    if (@editBox.shown)
      width = getWidth
      height = getItemHeight(@selectedItem)
      scrollbar = verticalScrollBar
      @editBox.position(x,y+(height*@selectedItem)-scrollbar.position,width-scrollbar.getWidth,height)
    end
    super
  end

  #Initializes the PathList with an array of paths
  def setItems(items)
    clearItems
    items.each do |itemText|
      appendItem(itemText)
    end
    appendItem(" ")
    @lastItem = getNumItems-1
  end

  #Returns an array containing all the paths in the PathList
  def getItems
    a = []
    0.upto(@lastItem-1) do |itemIndex|

      a << getItemText(itemIndex)
    end
    return a
  end

private

 #Remove the current list item
 def removeElement
   if (getCurrentItem >= 0)
     if (getCurrentItem==@lastItem)
       setItemText(@lastItem," ")
     else
       removeItem(getCurrentItem)
       @lastItem -= 1
     end
   end
 end

end