--- /dev/null
+// Because sometimes you need to style the cursor's line.
+//
+// Adds an option 'styleActiveLine' which, when enabled, gives the
+// active line's wrapping <div> the CSS class "CodeMirror-activeline",
+// and gives its background <div> the class "CodeMirror-activeline-background".
+
+(function() {
+ "use strict";
+ var WRAP_CLASS = "CodeMirror-activeline";
+ var BACK_CLASS = "CodeMirror-activeline-background";
+
+ CodeMirror.defineOption("styleActiveLine", false, function(cm, val, old) {
+ var prev = old && old != CodeMirror.Init;
+ if (val && !prev) {
+ updateActiveLine(cm);
+ cm.on("cursorActivity", updateActiveLine);
+ } else if (!val && prev) {
+ cm.off("cursorActivity", updateActiveLine);
+ clearActiveLine(cm);
+ delete cm.state.activeLine;
+ }
+ });
+
+ function clearActiveLine(cm) {
+ if ("activeLine" in cm.state) {
+ cm.removeLineClass(cm.state.activeLine, "wrap", WRAP_CLASS);
+ cm.removeLineClass(cm.state.activeLine, "background", BACK_CLASS);
+ }
+ }
+
+ function updateActiveLine(cm) {
+ var line = cm.getLineHandleVisualStart(cm.getCursor().line);
+ if (cm.state.activeLine == line) return;
+ clearActiveLine(cm);
+ cm.addLineClass(line, "wrap", WRAP_CLASS);
+ cm.addLineClass(line, "background", BACK_CLASS);
+ cm.state.activeLine = line;
+ }
+})();