Adding on_empty_keys patch ref. #51

README.md

@@ -15,6 +15,8 @@ Refer to [https://dwm.suckless.org/](https://dwm.suckless.org/) for details on t
 
 ### Changelog:
 
+2020-09-29 - Added the on\_empty\_keys patch (ported from InstantOS)
+
 2020-09-28 - Added the \_IS\_FLOATING patch (embedded in the EWMHTAGS patch)
 
 2020-09-18 - Added the nomodbuttons patch allowing for toggleable mouse button bindings that have no modifiers
@@ -426,6 +428,10 @@ Refer to [https://dwm.suckless.org/](https://dwm.suckless.org/) for details on t
       - this patch ensures that borders have no transparency
       - note that this patch is only relevant if you are not using the alpha patch
 
+   - [on\_empty\_keys](https://github.com/bakkeby/dwm-flexipatch/issues/51)
+      - port of InstantVM's on_empty_keys functionality allowing keybindings that apply only when a tag/view is empty
+      - an example use case is being able to launch applications with first hand keys like "f" to launch firefox
+
    - [onlyquitonempty](https://dwm.suckless.org/patches/onlyquitonempty/)
       - makes it so dwm will only exit via quit() if no windows are open (in order to prevent accidental loss of work)
 

config.def.h

@@ -733,6 +733,14 @@ static const char *statuscmds[] = { "notify-send Mouse$BUTTON" };
 static char *statuscmd[] = { "/bin/sh", "-c", NULL, NULL };
 #endif // BAR_STATUSCMD_PATCH | DWMBLOCKS_PATCH
 
+#if ON_EMPTY_KEYS_PATCH
+static const char* firefoxcmd[] = {"firefox", NULL};
+static Key on_empty_keys[] = {
+	/* modifier key            function                argument */
+	{ 0,        XK_f,          spawn,                  {.v = firefoxcmd } },
+};
+#endif // ON_EMPTY_KEYS_PATCH
+
 static Key keys[] = {
 	/* modifier                     key            function                argument */
 	#if KEYMODES_PATCH

dwm.c

@@ -420,6 +420,9 @@ struct Monitor {
 	unsigned int sellt;
 	unsigned int tagset[2];
 	int showbar;
+	#if ON_EMPTY_KEYS_PATCH
+	int isempty;
+	#endif // ON_EMPTY_KEYS_PATCH
 	Client *clients;
 	Client *sel;
 	Client *stack;
@@ -1813,6 +1816,13 @@ focus(Client *c)
 	}
 	selmon->sel = c;
 	drawbars();
+
+	#if ON_EMPTY_KEYS_PATCH
+	if ((selmon->isempty && selmon->sel) || (!selmon->isempty && !selmon->sel)) {
+		selmon->isempty = !selmon->isempty;
+		grabkeys();
+	}
+	#endif // ON_EMPTY_KEYS_PATCH
 }
 
 /* there are some broken focus acquiring clients needing extra handling */
@@ -2028,6 +2038,14 @@ grabkeys(void)
 				for (j = 0; j < LENGTH(modifiers); j++)
 					XGrabKey(dpy, code, keys[i].mod | modifiers[j], root,
 						True, GrabModeAsync, GrabModeAsync);
+		#if ON_EMPTY_KEYS_PATCH
+		if (!selmon->sel)
+			for (i = 0; i < LENGTH(on_empty_keys); i++)
+				if ((code = XKeysymToKeycode(dpy, on_empty_keys[i].keysym)))
+					for (j = 0; j < LENGTH(modifiers); j++)
+						XGrabKey(dpy, code, on_empty_keys[i].mod | modifiers[j], root,
+								True, GrabModeAsync, GrabModeAsync);
+		#endif // ON_EMPTY_KEYS_PATCH
 	}
 }
 
@@ -2073,6 +2091,14 @@ keypress(XEvent *e)
 				&& CLEANMASK(keys[i].mod) == CLEANMASK(ev->state)
 				&& keys[i].func)
 			keys[i].func(&(keys[i].arg));
+	#if ON_EMPTY_KEYS_PATCH
+	if (!selmon->sel)
+		for (i = 0; i < LENGTH(on_empty_keys); i++)
+			if (*keysym == on_empty_keys[i].keysym
+					&& CLEANMASK(on_empty_keys[i].mod) == CLEANMASK(ev->state)
+					&& on_empty_keys[i].func)
+				on_empty_keys[i].func(&(on_empty_keys[i].arg));
+	#endif // ON_EMPTY_KEYS_PATCH
 	XFree(keysym);
 }
 
@@ -2128,13 +2154,13 @@ manage(Window w, XWindowAttributes *wa)
 	c->cfact = 1.0;
 	#endif // CFACTS_PATCH
 	updatetitle(c);
-	#if CENTER_PATCH
-	if (c->x == c->mon->wx && c->y == c->mon->wy)
-		c->iscentered = 1;
-	#endif // CENTER_PATCH
 	if (XGetTransientForHint(dpy, w, &trans) && (t = wintoclient(trans))) {
 		c->mon = t->mon;
 		c->tags = t->tags;
+		#if CENTER_PATCH
+		if (c->x == c->mon->wx && c->y == c->mon->wy)
+			c->iscentered = 1;
+		#endif // CENTER_PATCH
 		#if SETBORDERPX_PATCH
 		c->bw = c->mon->borderpx;
 		#else
@@ -2151,6 +2177,10 @@ manage(Window w, XWindowAttributes *wa)
 		#endif // CENTER_TRANSIENT_WINDOWS_PATCH | CENTER_TRANSIENT_WINDOWS_BY_PARENT_PATCH
 	} else {
 		c->mon = selmon;
+		#if CENTER_PATCH
+		if (c->x == c->mon->wx && c->y == c->mon->wy)
+			c->iscentered = 1;
+		#endif // CENTER_PATCH
 		#if SETBORDERPX_PATCH
 		c->bw = c->mon->borderpx;
 		#else

patches.def.h

@@ -677,6 +677,15 @@
  */
 #define NO_TRANSPARENT_BORDERS_PATCH 0
 
+/* Port of InstantVM's on_empty_keys functionality allowing keybindings that apply only when
+ * a tag is empty. An example use case is being able to launch applications with first hand
+ * keys like "f" to launch firefox.
+ *
+ * https://github.com/instantOS/instantWM/
+ * https://github.com/bakkeby/dwm-flexipatch/issues/51
+ */
+#define ON_EMPTY_KEYS_PATCH 0
+
 /* Minor patch that prevents more than one rule being matched for a given client. */
 #define ONLY_ONE_RULE_MATCH_PATCH 0