Dynamically change height of BottomSheetBehavior

Question

I\'m using the BottomSheetBehavior from Google recently released AppCompat v23.2. The height of my bottom sheet depends on the content displayed inside of the b

Answer 1

For bottom sheet dialog fragment, read this: Bottom Sheet Dialog Fragment Expand Full Height

@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState) {
   super.onActivityCreated(savedInstanceState);

   BottomSheetDialog dialog = (BottomSheetDialog) getDialog();

   FrameLayout bottomSheet = dialog.findViewById(com.google.android.material.R.id.design_bottom_sheet);
   BottomSheetBehavior behavior = BottomSheetBehavior.from(bottomSheet);
   behavior.setState(BottomSheetBehavior.STATE_EXPANDED);
   behavior.setPeekHeight(0);
}

Answer 2

I had the same problem with RelativeLayout as my bottom sheet. The height won't be recalculated. I had to resort to setting the height by the new recalculated value and call BottomSheetBehavior.onLayoutChild.

This is my temporary solution:

coordinatorLayout = (CoordinatorLayout)findViewById(R.id.coordinator_layout);
bottomSheet = findViewById(R.id.bottom_sheet);

int accountHeight = accountTextView.getHeight();
accountTextView.setVisibility(View.GONE);

bottomSheet.getLayoutParams().height = bottomSheet.getHeight() - accountHeight;
bottomSheet.requestLayout();
behavior.onLayoutChild(coordinatorLayout, bottomSheet, ViewCompat.LAYOUT_DIRECTION_LTR);

Answer 3

I've been struggling with a problem similar to yours.

Manually setting the height of the bottomSheet was the solution for me.

Having a view viewA that has the BottomSheetBehaviour and a custom method modifyHeight() that modifies the height of the view:

viewA?.modifyHeight()
viewA?.measure(
            MeasureSpec.makeMeasureSpec(
                width,
                MeasureSpec.EXACTLY
            ),
            MeasureSpec.makeMeasureSpec(
                0,
                MeasureSpec.UNSPECIFIED
            )
        )
val layoutParams = LayoutParams(viewA.measuredWidth, viewA.measuredHeight)
val bottomSheet = BottomSheetBehavior.from(viewA)
layoutParams.behavior = bottomSheet
viewA.layoutParams = layoutParams

My layout would be something like:

    <com.yourpackage.ViewA
    android:id="@+id/viewA"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:behavior_peekHeight="50dp"
    app:layout_behavior="@string/bottom_sheet_behavior" />

It is important to reuse the bottomSheetBehaviour of the old layoutParams because it contains the peekHeight and listeners you may have attached.