Need to disable expand on CollapsingToolbarLayout for certain fragments

Question

I have a AppCompatActivity that controls replacing many fragments. Here is my layout for it.

activity_main.xml

Answer 1

I have used @JasonWyatt's solution and added DragCallback to behavior class to prevent touch and drag CollapsingToolbarLayout to expand it

private void setDragCallback() {
    setDragCallback(new DragCallback() {
        @Override
        public boolean canDrag(@NonNull AppBarLayout appBarLayout) {
            return mEnabled;
        }
    });
}

Answer 2

This class will let you disable/re-enable the expansion behavior.

public class DisableableAppBarLayoutBehavior extends AppBarLayout.Behavior {
    private boolean mEnabled;

    public DisableableAppBarLayoutBehavior() {
        super();
    }

    public DisableableAppBarLayoutBehavior(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public void setEnabled(boolean enabled) {
        mEnabled = enabled;
    }

    @Override
    public boolean onStartNestedScroll(CoordinatorLayout parent, AppBarLayout child, View directTargetChild, View target, int nestedScrollAxes) {
        return mEnabled && super.onStartNestedScroll(parent, child, directTargetChild, target, nestedScrollAxes);
    }

    public boolean isEnabled() {
        return mEnabled;
    }
}

Use it in your layout like so:

<android.support.design.widget.AppBarLayout
    ... other attributes ...
    app:layout_behavior="com.yourpackage.DisableableAppBarLayoutBehavior"
    >
    <!-- your app bar contents -->
</android.support.design.widget.AppBarLayout>

Then, when you want to disable the behavior:

AppBarLayout myAppBar = ....;
CoordinatorLayout.LayoutParams layoutParams = (CoordinatorLayout.LayoutParams) myAppBar.getLayoutParams();
((DisableableAppBarLayoutBehavior) layoutParams.getBehavior()).setEnabled(false);

Answer 3

With Android Design Library v23.1.1, the method described by @LucyFair does not work. I managed to get it to work by setting the app:layout_scrollFlags to enterAlwaysCollapsed only, and the appbar stays "locked".

Hope this helps. :)

Answer 4

I found Simple solution to enable/disable collapse in CollapsingToolbarLayout:

    private void setExpandEnabled(boolean enabled) {
        mAppBarLayout.setExpanded(enabled, false);
        mAppBarLayout.setActivated(enabled);
        final AppBarLayout.LayoutParams params = (AppBarLayout.LayoutParams) collapsingToolbarLayout.getLayoutParams();
        if (enabled)
            params.setScrollFlags(AppBarLayout.LayoutParams.SCROLL_FLAG_SCROLL | AppBarLayout.LayoutParams.SCROLL_FLAG_EXIT_UNTIL_COLLAPSED);
        else
            params.setScrollFlags(AppBarLayout.LayoutParams.SCROLL_FLAG_ENTER_ALWAYS | AppBarLayout.LayoutParams.SCROLL_FLAG_EXIT_UNTIL_COLLAPSED);
        collapsingToolbarLayout.setLayoutParams(params);
    }

Answer 5

Find the AppBarLayout id as like this.

appBarLayout = (AppBarLayout) findViewById(R.id.appbar);

Disable expand on CollapsingToolbarLayout for certain fragments

appBarLayout.setExpanded(true,true);

Enable expand on CollapsingToolbarLayout for certain fragments

appBarLayout.setExpanded(false,true);

Hope it will help you !!

Answer 6

Disable nested scrolling on the scrolling fragment content:

recyclerView.setNestedScrollingEnabled(false);

Use this if you're using the support library:

ViewCompat.setNestedScrollingEnabled(recyclerView, false);