applets/clipboard: Don't delete any item when the search field has focus
applets/clipboard: Don't delete any item when the search field has focus
The behavior may cause unexpected results when the user spam press Del in order to delete all characters in the search field, and find that all items in the list are deleted.
It also causes pressing Del in the search field not deleting the fully selected text.
applets/clipboard: Make Up/Down arrow keys work in ClipboardPage
ListView will absorb the key events, so Keys.onPressed in
ClipboardPage will not receive the event. Instead we should connect
those key events to arrowKeyPressed().
applets/clipboard: Focus on the search field for the first time opening the applet
So Up/Down key can navigate the list items instead of scrolling in the ListView.
Edited by Fushan Wen