[lazarus] clipboard is there

[Mattias Gaertner]

Hi

LCL has now more than a clipboard, it has three of them.


Features:
- a TClipboard object for each of the three selection types under gtk:
  PrimarySelection, SecondarySelection and Clipboard.
- Very similar to Delphis TClipboard.
- Internal caching. This accelerates access and makes it possible to use all
  three clipboards even under win32. (Although the Primary- and Secondary-
  Selection will only work within an application.)
- Putting data on demand. You can set the supported formats without setting
  the data. Just set the OnRequest event and put the data when someone
  requests a specific format. This makes it easy to use the PrimarySelection.
- The gtk interface automatically translates TEXT, STRING, COMPOUND_TEXT and
  text/plain to text and back.


Usage examples:

1. Putting text onto the clipboard:

  Clipboard.AsText := 'some text';


2. Getting text from the clipboard:

  MyString := Clipboard.AsText;


3. Registering a custom clipboard format:
  
  var MyCustomFormatID: TClipboardFormat;

  MyCustomFormatID := ClipboardRegisterFormat('My custom format');


4. The IDE itself:
  TSynEdit now supports the LCL clipboard.
  - Paste/Copy/Cut will use text and TSynEdits own text format
  - Setting the selection will also set the primary selection
  - Middle mouse button will insert the primary selection.


Mattias