2017-07-19 132 views
1

我幾乎沒有任何開發android應用程序的經驗。我的朋友問我爲他的應用程序創建一個小功能。我堅持的是爲選項創建一個子菜單,也就是說,我點擊了一個按鈕後,會彈出一個菜單並帶有一些選項,當點擊某個特定選項時我需要它打開第二個菜單。我會在下面發佈我的代碼(XML和Java),希望有人能幫助我。目前,我的菜單通過Java代碼顯示,而不是XML代碼。我不確定這是否是不好的練習,但我會讓任何能夠幫助我的人告訴我是否是這樣。提前致謝。在android中創建菜單/子菜單

XML代碼:

<?xml version="1.0" encoding="utf-8"?> 
<android.support.constraint.ConstraintLayout 
    xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:tools="http://schemas.android.com/tools" 
    xmlns:app="http://schemas.android.com/apk/res-auto" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    app:layout_behavior="@string/appbar_scrolling_view_behavior" 
    tools:showIn="@layout/activity_main" 
    tools:context="com.example.android.postvu.MainActivity"> 

<ImageView 
    android:id="@+id/imageView2" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:contentDescription="@string/background" 
    android:scaleType="centerCrop" 
    android:src="@drawable/grid" /> 

<TextView 
    android:id="@+id/textView" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:layout_marginLeft="8dp" 
    android:layout_marginRight="8dp" 
    android:layout_marginTop="8dp" 
    android:text="@string/image_text_editor" 
    android:textColor="@android:color/black" 
    android:textSize="28sp" 
    android:textStyle="bold" 
    app:layout_constraintLeft_toLeftOf="parent" 
    app:layout_constraintRight_toRightOf="parent" 
    app:layout_constraintTop_toTopOf="parent" 
    tools:text="Image Text Editor" /> 


<Button 
    android:layout_width="50dp" 
    android:layout_height="50dp" 
    android:layout_marginBottom="8dp" 
    android:layout_marginLeft="8dp" 
    android:layout_marginRight="8dp" 
    android:layout_marginTop="8dp" 
    android:background="@mipmap/ic_launcher" 
    android:scaleType="centerCrop" 
    android:onClick="myOnClickMethod" 
    app:layout_constraintBottom_toBottomOf="parent" 
    app:layout_constraintLeft_toLeftOf="parent" 
    app:layout_constraintRight_toRightOf="parent" 
    app:layout_constraintTop_toBottomOf="@+id/textView" 
    app:layout_constraintVertical_bias="0.98" /> 

的Java代碼(與該按鈕被點擊,菜單顯示出來):

public void myOnClickMethod(View v) { 
    registerForContextMenu(v); 
    openContextMenu(v); 
} 

final int CONTEXT_MENU_VIEW = 1; 
final int CONTEXT_MENU_EDIT = 2; 
final int CONTEXT_MENU_ARCHIVE = 3; 


@Override 
public void onCreateContextMenu (ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) { 
    menu.setHeaderTitle("Options"); 
    menu.add(Menu.NONE, CONTEXT_MENU_VIEW, Menu.NONE, "Take Photo"); 
    menu.add(Menu.NONE, CONTEXT_MENU_EDIT, Menu.NONE, "Photo Album"); 
    menu.add(Menu.NONE, CONTEXT_MENU_ARCHIVE, Menu.NONE, "Plain Image"); 
} 

@Override 
public boolean onContextItemSelected (MenuItem item) { 
    switch (item.getItemId()) { 
     case CONTEXT_MENU_VIEW: { 
     } 
     break; 
     case CONTEXT_MENU_EDIT: { 
     } 
     break; 
     case CONTEXT_MENU_ARCHIVE: { 
     } 
     break; 
    } 

    return super.onContextItemSelected(item); 
} 
+1

https://stackoverflow.com/a/21027948/4044380是什麼? – jagapathi

回答

0

您可以在下面顯示的子菜單辦法。我修改了你的代碼並使用了硬編碼的常量。我希望這能幫到您。

public class MainActivity extends AppCompatActivity { 
    private View menuAnchorView; 
    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 
     menuAnchorView = findViewById(R.id.imageView2); 
     menuAnchorView.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View view) { 
       myOnClickMethod(menuAnchorView); 
      } 
     }); 
    } 

    public void myOnClickMethod(View v) { 
     registerForContextMenu(v); 
     openContextMenu(v); 
    } 

    final int CONTEXT_MENU_VIEW = 1; 
    final int CONTEXT_MENU_EDIT = 2; 
    final int CONTEXT_MENU_ARCHIVE = 3; 


    @Override 
    public void onCreateContextMenu (ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) { 
     if(v.getTag() == null || !v.getTag().equals("menu_item")) { 
      menu.setHeaderTitle("Options"); 
      menu.add(Menu.NONE, CONTEXT_MENU_VIEW, Menu.NONE, "Take Photo"); 
      menu.add(Menu.NONE, CONTEXT_MENU_EDIT, Menu.NONE, "Photo Album"); 
      menu.add(Menu.NONE, CONTEXT_MENU_ARCHIVE, Menu.NONE, "Plain Image"); 
     } 
     else { 
      menu.setHeaderTitle("Sub menu"); 
      menu.add(Menu.NONE, 4, Menu.NONE, "Sub-view"); 
      menu.add(Menu.NONE, 5, Menu.NONE, "Sub-view-2"); 
     } 
    } 

    @Override 
    public boolean onContextItemSelected (MenuItem item) { 
     closeContextMenu(); 
     switch (item.getItemId()) { 
      case CONTEXT_MENU_VIEW: { 
       menuAnchorView.setTag("menu_item"); 
       openContextMenu(menuAnchorView); 
      } 
      break; 
      case CONTEXT_MENU_EDIT: { 
      } 
      break; 
      case CONTEXT_MENU_ARCHIVE: { 
      } 
      break; 
      case 4: 
      case 5: menuAnchorView.setTag(null); 
       break; 
     } 

     return super.onContextItemSelected(item); 
    } 

}