Pasting Selection With Middle-Click

There is another type of paste operation that is supported on Linux, specifically by the X11 window system used by Linux and MAC-OS.  The selection is made using the mouse by clicking at the start of the text and dragging to the end of the text.  This selection can then be pasted into any window using the middle mouse button (the button under the wheel on most modern mice).  Windows does not support this feature.

This paste operation is intercepted by reimplementing the mouse release event handler.  If the event has the middle mouse button, the clipboard is checked to see if it supports this type of selection.  If it does, the text() function is again used to obtain the text of the selection, however, instead of using the default argument (nothing), the QClipboard::Selection argument is used to get this selection text instead of the normal clipboard paste buffer text.  Otherwise, the mouse release event is passed to the mouse release event handler of the QPlainTextEdit base class.

There is one issue with this paste operation however.  The text is pasted at the current location of the text cursor, not where the mouse cursor is actually pointing to at the time of the middle button click.  This will be the subject of next post.

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