Added Modifier-only keybinding support

src/config/key_bindings.rs

@@ -90,11 +90,11 @@ pub struct KeyPattern {
     pub modifiers: KeyModifiers,
     /// The actual key, that was pressed
     #[serde(deserialize_with = "deserialize_Keysym")]
-    pub key: u32,
+    pub key: Option<u32>,
 }
 
 impl KeyPattern {
-    pub fn new(modifiers: impl Into<KeyModifiers>, key: u32) -> KeyPattern {
+    pub fn new(modifiers: impl Into<KeyModifiers>, key: Option<u32>) -> KeyPattern {
         KeyPattern {
             modifiers: modifiers.into(),
             key,
@@ -117,7 +117,12 @@ impl ToString for KeyPattern {
         if self.modifiers.shift {
             result += "Shift+";
         }
-        result += &keysym_get_name(self.key);
+
+        if let Some(key) = self.key {
+            result += &keysym_get_name(key);
+        } else {
+            result.remove(result.len() - 1);
+        }
         result
     }
 }
@@ -176,7 +181,7 @@ fn insert_binding(
         for key in keys {
             let pattern = KeyPattern {
                 modifiers: modifiers.clone(),
-                key,
+                key: Some(key),
             };
             if !key_bindings.contains_key(&pattern) {
                 key_bindings.insert(pattern, action.clone());

src/config/types.rs

@@ -56,13 +56,18 @@ where
 }
 
 #[allow(non_snake_case)]
-pub fn deserialize_Keysym<'de, D>(deserializer: D) -> Result<Keysym, D::Error>
+pub fn deserialize_Keysym<'de, D>(deserializer: D) -> Result<Option<Keysym>, D::Error>
 where
     D: serde::Deserializer<'de>,
 {
     use serde::de::{Error, Unexpected};
 
-    let name = String::deserialize(deserializer)?;
+    let name: Option<String> = Option::deserialize(deserializer)?;
+    if name.is_none() {
+        return Ok(None);
+    }
+
+    let name = name.unwrap();
     //let name = format!("KEY_{}", code);
     match xkb::keysym_from_name(&name, xkb::KEYSYM_NO_FLAGS) {
         KeySyms::KEY_NoSymbol => match xkb::keysym_from_name(&name, xkb::KEYSYM_CASE_INSENSITIVE) {
@@ -76,9 +81,9 @@ where
                     name,
                     xkb::keysym_get_name(x)
                 );
-                Ok(x)
+                Ok(Some(x))
             }
         },
-        x => Ok(x),
+        x => Ok(Some(x)),
     }
 }