adding sprite button example

Author: FoamyGuy

examples/bmps/gradient_button_0.bmp

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+# SPDX-FileCopyrightText: 2022 Tim Cocks for Adafruit Industries
+# SPDX-License-Identifier: MIT

examples/bmps/gradient_button_0.bmp.license

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+# SPDX-FileCopyrightText: 2022 Tim Cocks for Adafruit Industries
+# SPDX-License-Identifier: MIT

examples/bmps/gradient_button_1.bmp

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+# SPDX-FileCopyrightText: 2022 Tim Cocks for Adafruit Industries
+# SPDX-License-Identifier: MIT
+import time
+import board
+import displayio
+import adafruit_touchscreen
+import terminalio
+from adafruit_button.sprite_button import SpriteButton
+
+# These pins are used as both analog and digital! XL, XR and YU must be analog
+# and digital capable. YD just need to be digital
+ts = adafruit_touchscreen.Touchscreen(
+    board.TOUCH_XL,
+    board.TOUCH_XR,
+    board.TOUCH_YD,
+    board.TOUCH_YU,
+    calibration=((5200, 59000), (5800, 57000)),
+    size=(board.DISPLAY.width, board.DISPLAY.height),
+)
+
+# Make the display context
+main_group = displayio.Group()
+board.DISPLAY.show(main_group)
+
+BUTTON_WIDTH = 10 * 16
+BUTTON_HEIGHT = 3 * 16
+BUTTON_MARGIN = 20
+
+font = terminalio.FONT
+
+buttons = []
+
+
+button_0 = SpriteButton(
+    x=BUTTON_MARGIN,
+    y=BUTTON_MARGIN,
+    width=BUTTON_WIDTH,
+    height=BUTTON_HEIGHT,
+    label="button0",
+    label_font=font,
+    bmp_path="bmps/gradient_button_0.bmp",
+    selected_bmp_path="bmps/gradient_button_1.bmp",
+    transparent_index=0,
+)
+
+buttons.append(button_0)
+
+for b in buttons:
+    main_group.append(b)
+while True:
+    p = ts.touch_point
+    if p:
+        print(p)
+        for i, b in enumerate(buttons):
+            if b.contains(p):
+                print("Button %d pressed" % i)
+                b.selected = True
+                b.label = "pressed"
+            else:
+                b.selected = False
+                b.label = "button0"
+
+    else:
+        for i, b in enumerate(buttons):
+            if b.selected:
+                b.selected = False
+                b.label = "button0"
+    time.sleep(0.01)