Animate ProgressBar update in Android

Question

I am using a ProgressBar in my application which I update in onProgressUpdate of an AsyncTask. So far so good.

What I want to do is to animate the prog

Answer 1

I just wanted to add an extra value for those who want to use Data Binding with a progress bar animation.

First create the following binding adapter:

@BindingAdapter("animatedProgress")
fun setCustomProgressBar(progressBar: ProgressBar, progress: Int) {
    ObjectAnimator.ofInt(progressBar, "progress", progressBar.progress, progress).apply {
        duration = 500
        interpolator = DecelerateInterpolator()
    }.start()
}

And then use it in the layout which contains the ViewModel that reports the status updates:

<ProgressBar
    android:id="@+id/progress_bar_horizontal"
    style="?android:attr/progressBarStyleHorizontal"
    android:layout_width="0dp"
    android:layout_height="30dp"
    android:layout_marginStart="32dp"
    android:layout_marginEnd="32dp"
    android:indeterminate="false"
    android:max="100"
    app:animatedProgress="@{viewModel.progress ?? 0}"
    app:layout_constraintBottom_toBottomOf="parent"
    app:layout_constraintEnd_toEndOf="parent"
    app:layout_constraintStart_toStartOf="parent"
    app:layout_constraintTop_toTopOf="parent" />

The ViewModel itself will report the status with the following LiveData:

private val _progress = MutableLiveData<Int?>(null)
val progress: LiveData<Int?>
    get() = _