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libraries/lvgl/examples/widgets/dropdown/lv_example_dropdown_3.py

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+from imagetools import get_png_info, open_png
+
+# Register PNG image decoder
+decoder = lv.img.decoder_create()
+decoder.info_cb = get_png_info
+decoder.open_cb = open_png
+
+# Create an image from the png file
+try:
+    with open('../../assets/img_caret_down.png','rb') as f:
+        png_data = f.read()
+except:
+    print("Could not find img_caret_down.png")
+    sys.exit()
+
+img_caret_down_argb = lv.img_dsc_t({
+  'data_size': len(png_data),
+  'data': png_data
+})
+
+def event_cb(e):
+    dropdown = e.get_target()
+    option = " "*64 # should be large enough to store the option
+    dropdown.get_selected_str(option, len(option))
+    print(option.strip() +" is selected")
+#
+# Create a menu from a drop-down list and show some drop-down list features and styling
+#
+
+# Create a drop down list
+dropdown = lv.dropdown(lv.scr_act())
+dropdown.align(lv.ALIGN.TOP_LEFT, 10, 10)
+dropdown.set_options("\n".join([
+    "New project",
+    "New file",
+    "Open project",
+    "Recent projects",
+    "Preferences",
+    "Exit"]))
+
+# Set a fixed text to display on the button of the drop-down list
+dropdown.set_text("Menu")
+
+# Use a custom image as down icon and flip it when the list is opened
+# LV_IMG_DECLARE(img_caret_down)
+dropdown.set_symbol(img_caret_down_argb)
+dropdown.set_style_transform_angle(1800, lv.PART.INDICATOR | lv.STATE.CHECKED)
+
+# In a menu we don't need to show the last clicked item
+dropdown.set_selected_highlight(False)
+
+dropdown.add_event_cb(event_cb, lv.EVENT.VALUE_CHANGED, None)
+