File

Last Updated On 2021-07-16

Non-visible component for storing and retrieving files. Use this component to write or read files on your device. The default behaviour is to write files to the private data directory associated with your App. The Companion is special cased to write files to /sdcard/AppInventor/data to facilitate debugging. If the file path starts with a slash (/), then the file is created relative to /sdcard. For example writing a file to /myFile.txt will write the file in /sdcard/myFile.txt.

Properties

You can set the below properties in the UI part of the builder.

LegacyMode - it's a boolean value which is set to false by default.

Block Properties

You can set the below blocks properties in the blocks section of the builder.

LegacyMode

Allows app to access files from the root of the external storage directory (legacy mode).

Methods

You can set the below method blocks in the blocks section of the builder.

AppendToFile

Appends text to the end of a file storage, creating the file if it does not exist. See the help text under SaveFile for information about where files are written.

Delete

Deletes a file from storage. Prefix the filename with / to delete a specific file in the SD card, for instance /myFile.txt. will delete the file /sdcard/myFile.txt. If the file does not begin with a /, then the file located in the programs private storage will be deleted. Starting the file with // is an error because assets files cannot be deleted.

ReadFrom

Reads text from a file in storage. Prefix the filename with / to read from a specific file on the SD card. for instance /myFile.txt will read the file /sdcard/myFile.txt. To read assets packaged with an application (also works for the Companion) start the filename with // (two slashes). If a filename does not start with a slash, it will be read from the applications private storage (for packaged apps) and from /sdcard/AppInventor/data for the Companion.

SaveFile

Saves text to a file. If the filename begins with a slash (/) the file is written to the sdcard. For example writing to /myFile.txt will write the file to /sdcard/myFile.txt. If the filename does not start with a slash, it will be written in the programs private data directory where it will not be accessible to other programs on the phone. There is a special exception for the AI Companion where these files are written to /sdcard/AppInventor/data to facilitate debugging. Note that this block will overwrite a file if it already exists. If you want to add content to a file use the append block.

Events

You can set the below event blocks in the blocks section of the builder.

AfterFileSaved

Event indicating that the contents of the file have been written.

GotText

Event indicating that the contents from the file have been read.