如何在android（Kotlin）的中心设置BottomNavigationView项目

Question

我的 BottomNavigationView 中有 3 个项目，我使用此代码调整了每个项目的大小：

  val menuView = bottomNavigation.getChildAt(0) as BottomNavigationMenuView

        for (i in 0 until menuView.childCount) {
            val iconView = menuView.getChildAt(i).findViewById<View>(android.support.design.R.id.icon)
            val layoutParams = iconView.layoutParams
            val displayMetrics = resources.displayMetrics
            layoutParams.height = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 20f, displayMetrics).toInt()
            layoutParams.width = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 20f, displayMetrics).toInt()
            iconView.layoutParams = layoutParams

        }

现在这个项目不在底部导航视图的中心。可以请帮我用 Kotlin 方法将每个项目放在 BottomNavigationView 的中心吗？！

Answer 1

试试下面的东西

解决方案 1

public static void disableShiftMode(BottomNavigationView view) {
        BottomNavigationMenuView menuView = (BottomNavigationMenuView) view.getChildAt(0);
        try { 
            Field shiftingMode = menuView.getClass().getDeclaredField("mShiftingMode");
            shiftingMode.setAccessible(true);
            shiftingMode.setBoolean(menuView, false);
            shiftingMode.setAccessible(false);
            for (int i = 0; i < menuView.getChildCount(); i++) {
                BottomNavigationItemView item = (BottomNavigationItemView) menuView.getChildAt(i);
                //noinspection RestrictedApi 
                item.setShiftingMode(false);
                // set once again checked value, so view will be updated 
                //noinspection RestrictedApi 
                item.setChecked(item.getItemData().isChecked());
            } 
        } catch (NoSuchFieldException e) {
            Log.e("BNVHelper", "Unable to get shift mode field", e);
        } catch (IllegalAccessException e) {
            Log.e("BNVHelper", "Unable to change value of shift mode", e);
        } 
    }

解决方案 2

如果您使用的是最新的支持库，那么您可以使用此解决方案。 在xml中添加这一行

app:labelVisibilityMode="labeled"


<android.support.design.widget.BottomNavigationView
        android:id="@+id/navigation"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="0dp"
        android:layout_marginEnd="0dp"
        android:background="?android:attr/windowBackground"
        app:itemBackground="@drawable/home_bottom_bg_selector"
        app:itemIconTint="@color/home_bottom_text_selector"
        app:itemTextColor="@color/home_bottom_text_selector"
        app:labelVisibilityMode="labeled"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:menu="@menu/navigation" />