BottomNavigationView更换底部选中图标

1.去掉不显示图片默认颜色：

 navigationView.setItemIconTintList(null);

2.选中时替换icon：

private BottomNavigationView.OnNavigationItemSelectedListener mOnNavigationItemSelectedListener
            = new BottomNavigationView.OnNavigationItemSelectedListener() {

        @Override
        public boolean onNavigationItemSelected(@NonNull MenuItem item) {
            resetToDefaultIcon();//重置到默认不选中图片
            switch (item.getItemId()) {
                case R.id.navigation_home:
                    //在这里替换图标
                    item.setIcon(R.mipmap.ic_home_selected);
                    return true;
                ...
            }
            return false;
        }

    };

private void resetToDefaultIcon() {
        MenuItem home =  navigation.getMenu().findItem(R.id.navigation_home);
      home.setIcon(R.mipmap.ic_home_unselected);
        ...
       }