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javaandroidbottomnavigationview

Increase height of selected icon in navigation bottom view android when using custom icon?

Please, I want to use custom icon for bottom navigation view in android like this. How to change icon position when selected? When they are selected they go up a bit. Do you create a selected icon with a certain margin or is there a way to set the height in android? This image is from a flutter library though. I want to reproduce that in an Android Java project. Or find a library that implement it enter image description here

Solution

  • Inside your bottomNavigationView.setOnNavigationItemSelectedListener for each icon pressed call that animation method animateBottomIcon(int itemIndex, boolean isChecked). 

        BottomNavigationView bottomNav;
    BottomNavigationMenuView menuView;

    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
      bottomNav.setClipChildren(false);
      bottomNav.setClipToPadding(false);
      bottomNav.setClipToOutline(false);
      menuView.setClipChildren(false);
    menuView = (BottomNavigationMenuView) bottomNav.getChildAt(0);
}

private void animateBottomIcon(int itemIndex, boolean isChecked) {
        final View view = menuView.getChildAt(itemIndex).findViewById(com.google.android.material.R.id.icon);
        ObjectAnimator translateUpAnimator = ObjectAnimator.ofFloat(view, "translationY",
                0,
                (float) (-(bottomNav.getHeight() / 2))).setDuration(500);
        if(!isChecked) {
            translateUpAnimator.start();
        }
        if(currentItemIndex != -1) {
            final View currentView = menuView.getChildAt(currentItemIndex).findViewById(com.google.android.material.R.id.icon);
            ObjectAnimator translateDownAnimator = ObjectAnimator.ofFloat(currentView, "translationY",
                    0,
                    (float) (-(bottomNav.getHeight() / 2))).setDuration(500);
            if (!isChecked) {
                translateDownAnimator.reverse();
            }
        }
    }

    Usually the menu icon will be cut off by the BottomNavigation to avoid that use: android:clipChildren="false" on the root view of your layout, and in your java class, inside onCreateView():

    bottomNav.setClipChildren(false); bottomNav.setClipToPadding(false); bottomNav.setClipToOutline(false);

    and most importantly on your menuItem, because it's the parent of your icon items. menuView.setClipChildren(false);.

    Remember to give your bottom navigation view a fixed height.

    <com.google.android.material.bottomnavigation.BottomNavigationView
    android:id="@+id/bottom_nav"
    android:layout_width="match_parent"
    android:layout_height="56dp"
    app:layout_constraintBottom_toBottomOf="parent"
    android:layout_gravity="bottom"
    android:background="@color/white"
    app:itemIconSize="54dp"
    app:elevation="12dp"
    app:labelVisibilityMode="unlabeled"
    app:menu="@menu/menu_bottom_nav">[![enter image description here][1]][1]