added prototype for config dialog

frame.py

@@ -3,6 +3,7 @@ from bokeh.models import Button, Div, Spacer
 
 
 CROSS = "🗙"
+GEAR = "⚙"
 
 
 class Frame:
@@ -14,17 +15,47 @@ class Frame:
         name = plt.name
         inner_fig = plt.fig
 
+        n_btns = 2
         btn_width = 35
-        lbl_width = inner_fig.width - btn_width
+        lbl_width = inner_fig.width - n_btns * btn_width
+
+        self.btn_close = btn_close = Button(label=CROSS, button_type="default", width=btn_width)
+        self.btn_cfg   = btn_cfg   = Button(label=GEAR,  button_type="default", width=btn_width)
 
-        self.btn = btn = Button(label=CROSS, button_type="light", width=btn_width)
         lbl = Div(text=name, align="center", style={"font-size": "150%"}, width=lbl_width)
+        header = row(btn_close, btn_cfg, lbl)
 
-        self.fig = column(row(btn, lbl), inner_fig, Spacer(height=35))
+        self.cfg_dialog = cfg_dialog = column()
+        cfg_dialog.visible = False
+
+        #TODO: the following is just a dummy
+        types = ("light", "default", "primary", "success", "warning", "danger")
+        for t in types:
+            btn = Button(label=t, button_type=t, height=35) #TODO: why does this need height to be set? (otherwise buttons are only properly sized on NEXT click!)
+            cfg_dialog.children.append(btn)
+
+        self.btn_cfg.on_click(self.do_click_cfg)
+
+        # wrap fig and cfg such that their container can be hidden during the visibility switch
+        # wrap with another container to maintain size
+        # combined gives a relatively smooth (albeit slow) transition between the two states
+        self.inner = inner = row(inner_fig, cfg_dialog)
+        size_maintainer = row(inner, min_width=inner_fig.width, min_height=inner_fig.height) #TODO: why min_* ?
+
+        self.fig = column(header, size_maintainer, Spacer(height=35))
 
 
     def on_click_close(self, *args, **kwargs):
-        self.btn.on_click(*args, **kwargs)
+        self.btn_close.on_click(*args, **kwargs)
+
+    def do_click_cfg(self):
+        self.inner.visible = False
+        switch_visibility(self.plt.fig, self.cfg_dialog)
+        self.inner.visible = True
+
+
+def switch_visibility(a, b):
+    a.visible, b.visible = b.visible, a.visible