Fix bug in encoder-only mode.

README.md

@@ -312,17 +312,17 @@ runtime. A disabled `active` widget is shown "greyed-out" and cannot accept the
 
 ### 1.4.1 Encoder only mode
 
-This uses a rotary encoder with a pushbutton as the sole means of navigation, a
-mode suggested by @eudoxos. By default, turning the dial moves the currency
-between widgets. Clicking the button selects a widget; the widget with the
-focus has a white border. Supporting widgets such as sliders and dropdown lists
-enter "adjust" mode such that turning the dial adjusts the widget.
+This uses a rotary encoder with a built-in pushbutton as the sole means of
+navigation, a mode suggested by @eudoxos. By default, turning the dial moves
+the currency between widgets; the widget with the focus has a white border.
+Widgets for numeric entry such as sliders and scales may be put into "adjust"
+mode with a double click. In that mode turning the dial adjusts the widget.
 [Floating Point Widgets](./README.md#112-floating-point-widgets) can enter
-precision adjustment mode with a long press of the button. "Adjust" mode is
-cleared with a short button press.
+"precision" adjustment mode with a long press of the button. "Adjust" and
+"precision" modes are cleared with a short button press.
 
-This mode works well and its use is quite intuitive. The rapid navigation makes
-it particularly useful when a screen has a large number of widgets.
+This mode works well and its use is quite intuitive. Navigation by turning a
+dial makes it particularly useful when a screen has a large number of widgets.
 
 ###### [Contents](./README.md#0-contents)
 

gui/core/ugui.py

@@ -122,6 +122,8 @@ class Input:
 # nxt and prev are Pin instances corresponding to encoder X and Y.
 # sel is a Pin for the encoder's pushbutton.
 # encoder is the division ratio.
+# Note that using a single click for adjust mode failed because the mode changed when
+# activating pushbuttons, checkboxes etc.
 class InputEnc:
     def __init__(self, nxt, sel, prev, encoder):
         from gui.primitives import Encoder
@@ -132,18 +134,19 @@ class InputEnc:
         self._sel = Pushbutton(sel, suppress=True)
         self._sel.release_func(self.release)  # Widgets are selected on release.
         self._sel.long_func(self.precision, (True,))  # Long press -> precision mode
+        self._sel.double_func(self.adj_mode, (True,))  # Double press -> adjust mode
 
     # Screen.adjust: adjust the value of a widget. In this case 1st button arg
     # is an int (discarded), val is the delta. (With button interface 1st arg
-    # arg is the button, delta is +1 or -1).
-    def enc_cb(self, position, delta):  # Default encoder callback
+    # is the button, delta is +1 or -1).
+    def enc_cb(self, position, delta):  # Eencoder callback
         if self._adj:
             Screen.adjust(0, delta)
         else:
             Screen.ctrl_move(_NEXT if delta > 0 else _PREV)
 
     def release(self):
-        self.adj_mode() #False)  # Cancel adjust and precision
+        self.adj_mode(False)  # Cancel adjust and precision
         Screen.sel_ctrl()
         
     def precision(self, val):  # Also called by Screen.ctrl_move to cancel mode