main : two examples of how to add text to plots

plots/plot_text_overlay_using_annotations.py

@@ -4,17 +4,15 @@
 
 def add_plot_data():
     dpg.add_scatter_series([random() for i in range(10)], [random() for i in range(10)], parent="x-axis")
-    if dpg.does_item_exist("no_data_annotation"):
-        dpg.delete_item("no_data_annotation")
-        dpg.set_axis_limits_auto("x-axis") # unlock axis limits
-        dpg.set_axis_limits_auto("y-axis")
+    dpg.set_axis_limits_auto("x-axis") # unlock axis limits
+    dpg.set_axis_limits_auto("y-axis")
+    dpg.hide_item("no_data_annotation")
 
 def clear_plot():
     dpg.delete_item("x-axis", children_only=True)
     dpg.set_axis_limits("x-axis", 0, 1) 
     dpg.set_axis_limits("y-axis", 0, 1)
-    if not dpg.does_item_exist("no_data_annotation"):
-        dpg.add_plot_annotation(label="No Data Available", default_value=(0.5, 0.5), tag="no_data_annotation", parent="plot")
+    dpg.show_item("no_data_annotation")
 
 with dpg.window():
     dpg.set_primary_window(dpg.last_item(), True)

plots/plot_text_overlay_using_drawlist.py

@@ -0,0 +1,44 @@
+import dearpygui.dearpygui as dpg
+from random import random
+dpg.create_context()
+
+def add_plot_data():
+    dpg.add_scatter_series([random() for i in range(10)], [random() for i in range(10)], parent="x-axis")
+    dpg.hide_item("overlay_text")
+
+def clear_plot():
+    dpg.delete_item("x-axis", children_only=True)
+    dpg.show_item("overlay_text")
+
+with dpg.window(tag="primary_window"):
+    dpg.set_primary_window(dpg.last_item(), True)
+
+    with dpg.group(horizontal=True):
+        with dpg.child_window(width=200):
+            dpg.add_button(label="Add plot data", callback=add_plot_data)
+            dpg.add_button(label="Clear plot", callback=clear_plot)
+
+        with dpg.plot(width=-1, height=-1, tag="plot"):
+            dpg.add_plot_axis(dpg.mvXAxis, label="x-axis", tag="x-axis")
+            dpg.add_plot_axis(dpg.mvYAxis, label="y-axis", tag="y-axis")
+
+def set_overlay_text_position():
+    x,y = dpg.get_item_pos("plot")
+    w,h = dpg.get_item_rect_size("plot")
+    x_offset = -38 # needs a little manual adjustment to center
+    y_offset = -25
+    dpg.configure_item("overlay_text", pos=(x + w/2 + x_offset, y + h/2 + y_offset))
+
+with dpg.viewport_drawlist():
+    dpg.draw_text(pos=(100, 100), text="No Data Available", size=13, tag="overlay_text")
+
+with dpg.item_handler_registry() as registry:
+    dpg.add_item_resize_handler(callback=set_overlay_text_position)
+dpg.bind_item_handler_registry("primary_window", registry) 
+
+
+dpg.create_viewport(width=800, height=600, title="Plot text using drawlist overlay")
+dpg.setup_dearpygui()
+dpg.show_viewport()
+dpg.start_dearpygui()
+dpg.destroy_context()