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--- doc:appunti:prog:kivy [2019/03/01 13:00] – [A Real App With an ActionBar] niccolo
+++ doc:appunti:prog:kivy [2025/11/19 07:29] (current) – [Settings and Clipboard problem] niccolo
@@ Line 132: / Line 132: @@
 {{.:kivy:kivywindowexample.png?direct&320|Kivy ActionBar Example}}
-===== APK Packager =====
-  * **[[https://github.com/kivy/python-for-android|python-for-android]]**
+===== Logging =====
+Like a plain Python program, it is possible for a Kivy app to produce some logging using the Kivy logger. The output will go, by default, to a file created into the app home directory, into the **files/app/.kivy/logs/** directory.
+<code python>
+from kivy.logger import Logger, LOG_LEVELS
+# Set the loglevel. The Android log file will be create into
+# [app_home]/files/app/.kivy/logs/
+Logger.setLevel(LOG_LEVELS['debug'])
+Logger.info('Informative message')
+</code>
+Without root privileges it is not possibile for another Android app (e.g. a file browser) to access the log directory. The Kivy **app home** will be into the adopted SD card, under something like this:
+<code>
+/mnt/expand/[UUID]/user/0/[fully.qualified.app.name]
+</code>
+In older Android versions (e.g. Android 8) the app home directory will be something like:
+<code>
+/data/data/[fully.qualified.app.name]
+</code>
+Every time that the Kivy environment is initializated, a new log file will be created; the filename will be something like **kivy_YY-MM-DD_N.txt**, where YY-MM-DD is the date and N is a progressive integer starting from zero.
+===== The Settings module and Clipboard problem =====
+Importing **Settings** or **SettingsWithNoMenu** from the **kivy.uix.settings** module, you may get the following error when editing a string option:
+<code>
+[INFO   ]  [Clipboard] Provider: gtk3(['clipboard_xclip', 'clipboard_xsel',
+                       'clipboard_dbusklipper'] ignored)
+[CRITICAL] [Cutbuffer] Unable to find any valuable Cutbuffer provider. Please enable debug
+                       logging (e.g. add -d if running from the command line, or change the
+                       log level in the config) and re-run your app to identify potential
+                       causes
+</code>
+In Linux/X11 environment you have to install the **xclip** and **xsel** packages. In Android the error is displayed, but the program continues.