Extras: simplify calendar widget.

extras/widgets/calendar.py

@@ -22,6 +22,8 @@ class Calendar:
         self.date.callback = self.show
         rows = 6
         cols = 7
+        self.ncells = cols * (rows - 1)  # Row 0 has day labels
+        self.last_cell = cols * rows
         lw = (colwidth + 4) * cols  # Label width = width of grid
         kwargs = {"align": ALIGN_CENTER, "fgcolor": fgcolor, "bgcolor": bgcolor}
         self.lbl = Label(wri, row, col, lw, **kwargs)
@@ -31,53 +33,29 @@ class Calendar:
         self.grid[0, 0:7] = iter([d[:3] for d in DateCal.days])  # 3-char day names
         self.show()
 
-    def show(self):
-        def cell():  # Populate dict for a cell
-            d["fgcolor"] = self.fgcolor
-            d["bgcolor"] = self.bgcolor
-            if cur.year == today.year and cur.month == today.month and mday == today.mday:  # Today
-                if self.today_inv:
-                    d["fgcolor"] = self.bgcolor
-                    d["bgcolor"] = self.today_c
-                else:
-                    d["fgcolor"] = self.today_c
-            elif mday == cur.mday:  # Currency
-                if self.cur_inv:
-                    d["fgcolor"] = self.bgcolor
-                    d["bgcolor"] = self.cur_c                    
-                else:
-                    d["fgcolor"] = self.cur_c
-            elif mday in sundays:
-                d["fgcolor"] = self.sun_c
-            else:
-                d["fgcolor"] = self.fgcolor
-            d["text"] = str(mday)
-            self.grid[idx] = d
+    def days(self, month_length):  # Produce content for every cell
+        for n in range(self.ncells + 1):
+            yield str(n + 1) if n < month_length else ""
 
-        today = DateCal()
+    def show(self):
+        grid = self.grid
         cur = self.date  # Currency
         self.lbl.value(f"{DateCal.months[cur.month - 1]} {cur.year}")
-        d = {}  # Args for Label.value
-        wday = 0
-        wday_1 = cur.wday_n(1)  # Weekday of 1st of month
-        mday = 1
-        seek = True
-        sundays = cur.mday_list(6)
-        for idx in range(7, self.grid.ncells):
-            if seek:  # Find column for 1st of month
-                if wday < wday_1:
-                    self.grid[idx] = ""
-                    wday += 1
-                else:
-                    seek = False
-            if not seek:
-                if mday <= cur.month_length:
-                    cell()
-                    mday += 1
-                else:
-                    self.grid[idx] = ""
-        idx = 7  # Where another row would be needed, roll over to top few cells.
-        while mday <= cur.month_length:
-            cell()
-            idx += 1
-            mday += 1
+        values = self.days(cur.month_length)  # Instantiate generator
+        idx_1 = 7 + cur.wday_n(1)  # Index of 1st of month
+        grid[idx_1 : self.last_cell] = values
+        grid[7 : idx_1] = values
+        # Assign colors. Last to be applied has priority.
+        grid[1:6, 6] = {"fgcolor": self.sun_c}  # Sunday color
+        idx_cur = idx_1 + cur.mday - 1  # Currency (overrides Sunday)
+        if self.cur_inv:
+            grid[idx_cur] = {"fgcolor": self.bgcolor, "bgcolor": self.cur_c}
+        else:
+            grid[idx_cur] = {"fgcolor": self.cur_c}
+        today = DateCal()
+        if cur.year == today.year and cur.month == today.month:  # Today is in current month
+            idx = idx_1 + today.mday - 1
+            if self.today_inv:
+                grid[idx] = {"fgcolor": self.bgcolor, "bgcolor": self.fgcolor}
+            else:
+                grid[idx] = {"fgcolor": self.today_c}