Remove padding in horizontal progress bar

Question

In our application we need an indeterminate progress bar, like so:

We can achieve this by setting a negative margin on the ProgressBar, like this:

<ProgressBar
    android:id="@+id/progressbar"
    style="?android:attr/progressBarStyleHorizontal"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:indeterminate="true"
    android:marginTop="-7dp"
    android:visibility="@{loading ? View.VISIBLE : View.GONE}" />

BUT because ConstraintLayout does not support negative margins, it will look like this:

OK, the negative margin was a hack. Let's replace it with a different hack, shall we? Let's introduce our custom view CustomProgressBar, which extends ProgressBar and overrides its onDraw method, like this:

@Override
protected void onDraw(Canvas canvas) {
    int marginTop = dpToPx(7);
    canvas.translate(0, -marginTop);
    super.onDraw(canvas);
}

But all of this smells like bad code. There has to be a better solution! What would you recommend?

Answer 1

Solution that feels less like a hack: Wrap a huge ProgressBar in a smaller FrameLayout. That way the FrameLayout constrains its height, but the ProgressBar still shows in full.

<FrameLayout
    android:layout_width="match_parent"
    android:layout_height="4dp">

    <ProgressBar
        style="?android:attr/progressBarStyleHorizontal"
        android:layout_width="match_parent"
        android:layout_height="32dp"
        android:layout_gravity="center" />

</FrameLayout>