(cherry-pick) Fixed bug [1927212] - MouseWheel unbound for non-aqua scrollbars

2 files changed, 19 insertions, 0 deletions

diff --git a/library/scrlbar.tcl b/library/scrlbar.tcl
index 4b25325..7cec556 100644
--- a/library/scrlbar.tcl
+++ b/library/scrlbar.tcl
@@ -141,6 +141,10 @@ if {[tk windowingsystem] eq "aqua"} {
     bind Scrollbar <Shift-Option-MouseWheel> {
         tk::ScrollByUnits %W h [expr {-10 * (%D)}]
     }
+} else {
+    bind Scrollbar <MouseWheel> {
+        tk::ScrollByUnits %W v [expr {- (%D/120)}]
+    }
 }
 # tk::ScrollButtonDown --
 # This procedure is invoked when a button is pressed in a scrollbar.
diff --git a/tests/scrollbar.test b/tests/scrollbar.test
index 5d4334f..10aa7d6 100644
--- a/tests/scrollbar.test
+++ b/tests/scrollbar.test
@@ -632,6 +632,21 @@ test scrollbar-9.1 {scrollbar widget vs hidden commands} {
     list [winfo children .] [interp hidden]
 } [list {} $l]
 
+test scrollbar-10.1 {<MouseWheel> event on scrollbar} -constraints win -setup {
+    destroy .t .s
+} -body {
+    pack [text .t -yscrollcommand {.s set}] -side left
+    for {set i 1} {$i < 100} {incr i} {.t insert end "Line $i\n"}
+    pack [scrollbar .s -command {.t yview}] -fill y -expand 1 -side left
+    update
+    focus -force .s
+    event generate .s <MouseWheel> -delta -120
+    after 200 {set eventprocessed 1} ; vwait eventprocessed
+    .t index @0,0
+} -cleanup {
+    destroy .t .s
+} -result {2.0}
+
 catch {destroy .s}
 catch {destroy .t}