examples(micropython): add a few missing MP examples (#3672)

examples/others/gridnav/lv_example_gridnav_3.py

@@ -0,0 +1,84 @@
+def cont_sub_event_cb(e):
+    k = e.get_key()
+    obj = e.get_current_target()
+    if k == lv.KEY.ENTER:
+        lv.group_focus_obj(obj)
+
+    elif k == lv.KEY.ESC:
+        obj.get_group().focus_next()
+
+#
+# Nested grid navigations
+#
+# It's assumed that the default group is set and
+# there is a keyboard indev*/
+
+cont_main = lv.obj(lv.scr_act())
+lv.gridnav_add(cont_main,lv.GRIDNAV_CTRL.ROLLOVER | lv.GRIDNAV_CTRL.SCROLL_FIRST)
+
+# Only the container needs to be in a group
+lv.group_get_default().add_obj(cont_main)
+
+# Use flex here, but works with grid or manually placed objects as well
+cont_main.set_flex_flow(lv.FLEX_FLOW.ROW_WRAP)
+cont_main.set_style_bg_color(lv.palette_lighten(lv.PALETTE.BLUE, 5), lv.STATE.FOCUSED)
+cont_main.set_size(lv.pct(80), lv.SIZE_CONTENT)
+
+btn = lv.btn(cont_main)
+lv.group_remove_obj(btn)
+label = lv.label(btn)
+label.set_text("Button 1")
+
+btn = lv.btn(cont_main)
+lv.group_remove_obj(btn)
+label = lv.label(btn)
+label.set_text("Button 2");
+
+
+# Create an other container with long text to show how LV_GRIDNAV_CTRL_SCROLL_FIRST works
+cont_sub1 = lv.obj(cont_main)
+cont_sub1.set_size(lv.pct(100), 100)
+
+label = lv.label(cont_sub1)
+cont_sub1.set_style_bg_color(lv.palette_lighten(lv.PALETTE.RED, 5), lv.STATE.FOCUSED)
+label.set_width(lv.pct(100));
+label.set_text(
+    """I'm a very long text which makes my container scrollable. 
+    As LV_GRIDNAV_FLAG_SCROLL_FIRST is enabled arrows will scroll me first 
+    and a new objects will be focused only when an edge is reached with the scrolling.\n
+    This is only some placeholder text to be sure the parent will be scrollable. \n
+    Hello world!
+    Hello world!
+    Hello world!
+    Hello world!
+    Hello world!
+    Hello world!
+    """)
+
+# Create a third container that can be focused with ENTER and contains an other grid nav
+cont_sub2 = lv.obj(cont_main)
+lv.gridnav_add(cont_sub2, lv.GRIDNAV_CTRL.ROLLOVER)
+#Only the container needs to be in a group
+lv.group_get_default().add_obj(cont_sub2)
+
+cont_sub2.add_event_cb(cont_sub_event_cb, lv.EVENT.KEY, None)
+
+# Use flex here, but works with grid or manually placed objects as well
+cont_sub2.set_flex_flow(lv.FLEX_FLOW.ROW_WRAP)
+cont_sub2.set_style_bg_color(lv.palette_lighten(lv.PALETTE.RED, 5), lv.STATE.FOCUSED)
+cont_sub2.set_size(lv.pct(100), lv.SIZE_CONTENT)
+
+label = lv.label(cont_sub2)
+label.set_text("Use ENTER/ESC to focus/defocus this container")
+label.set_width(lv.pct(100))
+
+btn = lv.btn(cont_sub2)
+lv.group_remove_obj(btn)
+label = lv.label(btn)
+label.set_text("Button 3")
+
+btn = lv.btn(cont_sub2)
+lv.group_remove_obj(btn)
+label = lv.label(btn)
+label.set_text("Button 4")
+