4fd043398a
* FBT: file_assets generator * Elf file: process manifest section externally * FBT, file_assets generator: add assets signature * Storage: assets path alias * Flipper application: assets unpacker * Apps, Storage: use '/data' alias for apps data * Storage: copy file to file * Assets: log flag, fixes * Update f18 api * Assets: asserts * Assets: fix signature_data check * App assets: example * Example assets: fix folder structure in readme * Assets: fix error handling * Assets builder: use ansii instead of utf-8, use .fapassets section instead of .fapfiles, add assets path to signature * Elf file: comment strange places * Storage: totaly optimized storage_file_copy_to_file |
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files | ||
application.fam | ||
example_apps_assets.c | ||
README.md |
Apps Assets folder Example
This example shows how to use the Apps Assets folder to store data that is not part of the application itself, but is required for its operation, and that data is provided with the application.
What is the Apps Assets Folder?
The Apps Assets folder is a folder where external applications unpack their assets.
The path to the current application folder is related to the appid
of the app. The appid
is used to identify the app in the app store and is stored in the application.fam
file.
The Apps Assets folder is located only on the external storage, the SD card.
For example, if the appid
of the app is snake_game
, the path to the Apps Assets folder will be /ext/apps_assets/snake_game
. But using raw paths is not recommended, because the path to the Apps Assets folder can change in the future. Use the /assets
alias instead.
How to get the path to the Apps Assets folder?
You can use /assets
alias to get the path to the current application data folder. For example, if you want to open a file database.txt
in the Apps Assets folder, you can use the next path: /data/database.txt
. But this way is not recommended, because even the /assets
alias can change in the future.
We recommend to use the APP_ASSETS_PATH
macro to get the path to the Apps Assets folder. For example, if you want to open a file database.txt
in the Apps Assets folder, you can use the next path: APP_ASSETS_PATH("database.txt")
.
What is the difference between the Apps Assets folder and the Apps Data folder?
The Apps Assets folder is used to store the data provided with the application. For example, if you want to create a game, you can store game levels (contant data) in the Apps Assets folder.
The Apps Data folder is used to store data generated by the application. For example, if you want to create a game, you can save the progress of the game (user-generated data) in the Apps Data folder.
How to provide the data with the app?
To provide data with an application, you need to create a folder inside your application folder (eg "files") and place the data in it. After that, you need to add fap_file_assets="files"
to your application.fam file.
For example, if you want to provide game levels with the application, you need to create a "levels" folder inside the "files" folder and put the game levels in it. After that, you need to add fap_file_assets="files"
to your application.fam file. The final application folder structure will look like this:
snake_game
├── application.fam
├── snake_game.c
└── files
└── levels
├── level1.txt
├── level2.txt
└── level3.txt
When app is launched, the files
folder will be unpacked to the Apps Assets folder. The final structure of the Apps Assets folder will look like this:
/assets
├── .assets.signature
└── levels
├── level1.txt
├── level2.txt
└── level3.txt
When will the data be unpacked?
The data is unpacked when the application starts, if the application is launched for the first time, or if the data within the application is updated.
When an application is compiled, the contents of the "files" folder are hashed and stored within the application itself. When the application starts, this hash is compared to the hash stored in the .assets.signature
file. If the hashes differ or the .assets.signature
file does not exist, the application folder is deleted and the new data is unpacked.