The difficult art of explaning
Posted by Esben Mose Hansen
Sometimes, explaining abstract concepts concisely in an easy-to-understand language is everything but simple. Consider Klipper's config dialog as I recently adjusted it to look
Now, if you already know the difference between selection and primary when talking about the X clipboard, the radio button and the check box are both pretty clear, at least in my opinion. If not, I hope that the verbose what-is text might bridge the confusion, but I am not so sure. So, dear readers, do any of you understand what I'm trying to say? Can some of it be clearer? If you do not understand what I'm going on about, see below, where I'll try to explain at length what selection and primary is all about.
X does not have one clipboard but several clipboards, of which 2 are actually commonly used. They are often named after their XAtoms, "SELECTION" and "PRIMARY". Traditionally, X has supported highlightning an area with the mouse and then middle-clicking to paste this selection elsewhere. This is done via the SELECTION clipboard. Practically speaking, that means that if an area is selected in well-behaved X program XAPP, it will notify X that that XAPP now has the SELECTION. Thus, when the middle mouse button is clicked somewhere, the clicked application can ask X "give me the contents of SELECTION", and X can send the request on to XAPP, which can then send back the answer. Reasonable simple, even if I did leave out all the details about formats. Completely independent of this, X also has a clipboard like known in most other desktop environments, in which the user, usually by a keystroke like ctrl-C or a menu selection makes the application tell X "I now have the PRIMARY", and when the user selects paste somewhere, the content of the PRIMARY is pasted via. the same mechanism as the SELECTION above.
Now, many people find this to be confusing and/or annoying in practice. Keeping track of 2 different clipboards requires the user to remember "Did I just select it or did I copy it to the clipboard? If I selected it, I have to grab my mouse and use the middle button, otherwise I will have to press ctrl-V to paste." Thus, Klipper provide the ability to synchronize the PRIMARY and the SELECTION, ensuring that whatever method the user used to copy to the clipboard(s), all methods works for pasting. For the traditionalists, the option to keep the clipboards separate is also provided.
So what is this "ignore selection" all about? Well, if you use the separate option above, the clipboard history will still be populated from the mouse selection, and Klipper's actions will still be triggered. Some people do not want this: they wish Klipper to keep its endearing hands off SELECTION and only act on PRIMARY. So that is the last option. This will make the clipboard be almost completely like the Windows clipboard, except that you can still accidentally paste the mouse selection by pressing the middle mouse button, which is an X thing through and through.
Again, I'd value people's comments, and I do believe the comment system is actually working now. Otherwise, please direct comments to me by email.
PS: Now at 98 bugs. They seem to come in as quickly as I can fix them.
