Smooth Progress Bar Animation

Question

I'm trying to implement a smooth animation for my ProgressBar, but when I increase the time (30 seconds), the animation is no longer smooth.

Example with 5 seconds:

Example with 30 seconds:

My progress background:

<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
    <item>
        <shape>
            <padding android:top="1dp" />
            <solid android:color="#10444444" />
        </shape>
    </item>
    <item>
        <shape>
            <padding android:top="1dp" />
            <solid android:color="#20444444" />
        </shape>
    </item>
    <item>
        <shape>
            <padding android:top="1dp" />
            <solid android:color="#30444444" />
        </shape>
    </item>
    <item android:id="@android:id/background">
        <shape>
            <solid android:color="@color/black_thirty" />
        </shape>
    </item>

    <item android:id="@android:id/progress">
        <clip>
            <shape>
                <solid android:color="#3500D0" />
            </shape>
        </clip>
    </item>
</layer-list> 

My progress layout:

<ProgressBar
    android:id="@+id/pb_loading"
    android:layout_width="match_parent"
    android:layout_height="8dp"
    android:indeterminate="false"
    android:layout_centerInParent="true"
    android:progress="100"
    android:progressDrawable="@drawable/my_progress_bar" />

My animation method:

private void startAnimation(){
    ProgressBar mProgressBar = (ProgressBar) findViewById(R.id.pb_loading);
    ObjectAnimator progressAnimator = ObjectAnimator.ofInt(mProgressBar, "progress", 100, 0);
    progressAnimator.setDuration(30000);
    progressAnimator.setInterpolator(new LinearInterpolator());
    progressAnimator.start();
}

Answer 1

If you change progress value each time by 1 (for example from 45 to 46) you won't see the animation. You'd better change progress by 100 points (or maybe other), for this you just need to multiply your max value by 100 and each progress value to 100 too. For example:

    private void setProgressMax(ProgressBar pb, int max) {
        pb.setMax(max * 100);
    }

    private void setProgressAnimate(ProgressBar pb, int progressTo) 
    {
        ObjectAnimator animation = ObjectAnimator.ofInt(pb, "progress", pb.getProgress(), progressTo * 100);
        animation.setDuration(500);
        animation.setInterpolator(new DecelerateInterpolator());
        animation.start();
    }