Thumbnail Cleaner

This type of cleaner is used to clean up the ../.thumblails system folder. This folder is responsible for storing the cache of thumbnails of images on the device. With this type of cleaner, you can get a list of all files in the ../.thumbnails system folder and delete the selected ones.

important

Starting with Android 10, devices use a new type of Scoped Storage. For the thumbnail cleaner to work within Scoped Storage, you need a MANAGE_EXTERNAL_STORAGE permission

Analysis

The following code example demonstrates how to use the analysis operation:

// Get the thumbnail cleaner through the cleaner manager
val thumbCleaner = CleanerManagerFactory.cleanerManager.getCleaner(CleanerType.THUMBNAIL)

// Get coroutine scope to call cleaner library functions
val cleanerScope = CleanerManagerFactory.cleanerManager.scope

// Run all operations related to libraries only in the cleaner library
cleanerScope.launch {
    
    // Start the analysis process with the following call
    thumbCleaner.analyze(
        isFullRefresh = true
    )
}

The cleaner is represented by an object that implements the interface Cleaner, the method analyze which takes isFullRefresh: Boolean:

• true - when analyzing, the cleaner scans the system again;
• false - the method returns the cached result of the parsing (only non-deleted items).

Cleaning

Use the following code example to clear items.

// Get the thumbnail cleaner through the cleaner manager
val thumbCleaner = CleanerManagerFactory.cleanerManager.getCleaner(CleanerType.THUMBNAIL)

// Get coroutine scope to call cleaner library functions
val cleanerScope = CleanerManagerFactory.cleanerManager.scope

// Get a list of items to remove
val trashItemList: List<TrashItem>

// Run all operations related to libraries only in the cleaner library
cleanerScope.launch {
    // Start the analysis process with the following call
    thumbCleaner.clean(
        content = trashItemList
    )
}

A cleaner is represented by an object that implements the Cleaner interface, whose clean method accepts content: List<TrashItem> (list of items to remove)

Getting results

In order to get the state of the cleaner and the results of its work, you need to subscribe to its state as follows:

// Get the thumbnail cleaner through the cleaner manager
val thumbCleaner = CleanerManagerFactory.cleanerManager.getCleaner(CleanerType.THUMBNAIL)

// Get coroutine scope to call cleaner library functions
val cleanerScope = CleanerManagerFactory.cleanerManager.scope

// Run all operations related to libraries only in the cleaner library
cleanerScope.launch {
    // Subscribe to the states of the thumbnail cleaner
    thumbCleaner.stateFlow.collect { cleanerState -> // cleanerState: CleanerState
        // Do something...
    }
}

Thumbnail cleaner inherits Cleaner interface that provides stateFlow: StateFlow (StateFlow) which emits CleanerState objects containing information about the condition of the cleaner. Here are the following possible states of the cleaner:

Inactive - this is the initial state of the cleaner before starting work.

Analyzing - this state indicates that the cleaner is in the process of analyzing data. It includes the following fields:

• itemCount: Int - number of items found
• size: Long - size of found elements in bits

Analysed - this state indicates that the cleaner has finished analyzing the data. It includes the following fields:

• items: List<ThumbItem> - list of found items
• error: Trowable? - an error occurred during the analysis process

Cleaning -this state indicates that the cleaner is in the process of deleting data. It includes the following fields:

• itemCount: Int - number of items found
• size: Long - size of found elements in bits

Cleaned - this state indicates that the cleaner has completed the data cleaning process. It includes the following fields:

• items: List<ThumbItem> - list of deleted items
• error: Trowable? - an error occurred during the cleaning process

Links - CleanerState, ThumbItem, Cleaner.