AsyncViewPool

A library to asynchronously inflate views ahead of time to use later, with automatic memory management.

Installation

TODO

Usage

Create a pool:

val viewPool = AsyncViewPool(context)

Or to provide the correct LayoutParams (such as when using in a RecyclerView)

val viewPool = AsyncViewPool(viewGroup)

Inflate some views ahead of time:

//inflates 1x R.layout.my_layout
viewPool.inflate(R.layout.my_layout)

//inflates 10x R.layout.my_layout
viewPool.inflate(R.layout.my_layout, 10) 

//inflate several layouts once
viewPool.inflate(
    listOf(R.layout.my_layout, R.layout.my_layout_2)
)

//inflate using a parent (for example a RecyclerView), defaults to the ViewGroup provided in the constructor
viewPool.inflate(R.layout.my_layout, parent)

Retrieve the View when you need it:

val view: View? = viewPool.getView(R.layout.my_layout)

or if you want to inflate one immediately on the UI thread when one isn't available:

val view: View = viewPool.getViewOrInflate(R.layout.my_layout)

Destroy the AsyncViewPool when finished:

override fun onDestroy() {
    super.onDestroy()
    //very important that we destroy the ViewPool once we no longer need it. Failing to do so will result in a memory leak
    viewPool?.destroy()
}

A full example is in the sample app

Debugging

Not all layouts can be inflated asynchronously. Layouts which contain a fragment tag and views which create a Handler or access Looper.myLooper() will fail and instead resort to inflating on the UI thread. To identify these cases, look at the logcat for the following message:

Failed to inflate resource in the background! Retrying on the UI thread android.view.InflateException: Binary XML file line #6: Binary XML file line #6: Error inflating class android.webkit.WebView Caused by: android.view.InflateException: Binary XML file line #6: Error inflating class android.webkit.WebView

You can also enable setDebug(true) on the AsyncViewPool instance to debug the following:

• When a layout has been requested to be inflated
• When a layout has been removed from the pool
• When a layout has been removed from the pool due to changes in lifecycle/memory