New Graph Element - drag a square around with mouse... thanks to @davesmivers for original base code....

DemoPrograms/Demo_Graph_Drag_Rectangle_Super_Simple.py

@@ -0,0 +1,44 @@
+import PySimpleGUI as sg
+
+"""
+    Demo - Drag a rectangle and move
+
+    This demo shows how to use a Graph Element to draw a square and move it with the mouse.
+    It's a very simple, single element program.  Like many Demo Programs, it started as
+        a "Test Harness" that demonstrated a bug that happened with a timeout of 0
+        was added to the window.read()    
+
+    Original code comes courtesy of user @davesmivers .... Thanks Dave!!
+
+    Copyright 2022 PySimpleGUI
+"""
+
+
+GRAPH_SIZE = (400, 400)
+START = (200, 200)       # We'll assume X and Y are both this value
+SQ_SIZE = 40                # Both width and height will be this value
+
+layout = [[sg.Graph(
+            canvas_size=GRAPH_SIZE, graph_bottom_left=(0, 0), graph_top_right=GRAPH_SIZE,   # Define the graph area
+            change_submits=True,    # mouse click events
+            drag_submits=True,      # mouse move events
+            background_color='lightblue',
+            key="-GRAPH-",
+            pad=0)]]
+
+window = sg.Window("Simple Square Movement", layout, finalize=True, margins=(0,0))
+
+# draw the square we'll move around
+square = window["-GRAPH-"].draw_rectangle(START, (START[0]+SQ_SIZE, START[1]+SQ_SIZE), fill_color='black')
+
+while True:
+    event, values = window.read()
+    if event == sg.WIN_CLOSED:
+        break
+    print(event, values) if event != sg.TIMEOUT_EVENT else None # our normal debug print, but for this demo, don't spam output with timeouts
+
+    if event == "-GRAPH-":  # if there's a "Graph" event, then it's a mouse movement. Move the square
+        x, y = values["-GRAPH-"]        # get mouse position
+        window["-GRAPH-"].relocate_figure(square, x - SQ_SIZE // 2, y + SQ_SIZE // 2)   # Move using center of square to mouse pos
+
+window.close()