setVisibility不DrawerNavigation

Question

工作。我正在使用抽屜NavigationView並且在其中具有app:actionLayout屬性定向到包含TextView一個LinearLayout的Menu一個項目，而TextView具有財產android:visibility="invisible"。當點擊Menu中的item時，我想要這個textview可見。但它不起作用，我添加了Toast來檢查點擊偵聽器是否正常工作，並且發現點擊偵聽器正在工作，但是textView不可見。

這裏是點擊監聽器（活動佈局的名字是：main_activity.xml）：

navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() { 
      @Override 
      public boolean onNavigationItemSelected(@NonNull MenuItem item) { 
       switch (item.getItemId()){ 
        case R.id.nav_kitchen_key: 
         View kitchenKeyLayout = getLayoutInflater().inflate(R.layout.nav_kitchen_key, null); 
         TextView kitchenKeyTextView = (TextView)kitchenKeyLayout.findViewById(R.id.show_kitchen_key); 
         kitchenKeyTextView.setVisibility(View.VISIBLE); 
         break; 
       } 
       return true; 
      } 
     }); 

這裏是Menu item：

<item 
    android:id="@+id/nav_kitchen_key" 
    android:title="Kitchen Key" 
    android:icon="@drawable/if_key" 
    app:actionLayout="@layout/nav_kitchen_key" /> 

我的財產NU項目app:actionLayout引導到nav_kitchen_key.xml這裏是nav_kitchen_key.xml：

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    android:orientation="vertical" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:gravity="center_vertical"> 

     <TextView 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:id="@+id/show_kitchen_key" 
      android:textColor="@color/white" 
      android:text="2592" 
      android:visibility="invisible" 
      android:background="@drawable/kitchen_key_background"/> 

</LinearLayout> 

Answer 1

你不應該創建新的視圖，你應該從菜單項得到，MenuItem.getActionView()

navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() { 
      @Override 
      public boolean onNavigationItemSelected(@NonNull MenuItem item) { 
       switch (item.getItemId()){ 
        case R.id.nav_kitchen_key: 
         LinearLayout kitchenKeyLayout = (LinearLayout) item.getActionView(); 

         TextView kitchenKeyTextView = (TextView)kitchenKeyLayout.findViewById(R.id.show_kitchen_key); 
         kitchenKeyTextView.setVisibility(View.VISIBLE); 
         break; 
       } 
       return true; 
      } 
     }); 

Answer 2

您從getActionView

得到一個視圖

LinearLayout kitchenKeyLayout = (LinearLayout) item.getActionView(); 
    // This returns the container layout 

TextView kitchenKeyTextView = (TextView)kitchenKeyLayout.findViewById(R.id.show_kitchen_key); 
          kitchenKeyTextView.setVisibility(View.VISIBLE); 

kitchenKeyTextView.setVisibility(View.VISIBLE);