突出显示可扩展列表视图上的所有选定项目

问题描述:

我试图突出显示expandablelistview中的一个或多个项目。我找到了很多解决方案,但没有任何可以帮助我。 我希望有人能帮助我。我有一个鸡尾酒数据库。在应用程序中,您可以创建一个新的鸡尾酒。鸡尾酒的成分应该由用户在可扩展列表视图中选择。我只能同时突出显示一个项目。但为了更好的用户体验,用户可以选择多个项目很重要。如果他选择了所有成分,他可以保存他的选择,活动将关闭。如果他忘记了一种成分,那么他可以再次开始活动,他会看到所有突出显示的项目,他已经选择并选择了被遗忘的项目。突出显示可扩展列表视图上的所有选定项目

我希望,我的英语不是很糟糕,你可以理解我的意思并帮助我。

这里是将开始选择鸡尾酒配料的活动:

public class SelectIngredientByCategory extends AppCompatActivity { 
private ExpandableListView ingredients; 
private ExpandableListAdapter listAdapter; 
private List<String> listDataHeader; 
private HashMap<String, List<String>> listDataChild; 
private DBConnection db; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_select_ingredient_by_category); 

    db = new DBConnection(getApplication()); 

    /* ... */ 

    ingredients = (ExpandableListView) findViewById(R.id.elvIngredientsByCategory); 
    prepareListData(); 
    listAdapter = new ExpandableListAdapter(getApplication(), listDataHeader, listDataChild); 

    ingredients.setAdapter(listAdapter); 
    ingredients.setOnChildClickListener(new ExpandableListView.OnChildClickListener() { 
     @Override 
     public boolean onChildClick(ExpandableListView parent, View v, int groupPosition, int childPosition, long id) { 
      String ingredientName = (String) listAdapter.getChild(groupPosition, childPosition); 

      /* ... */ 

      /* 
      * if item is selected 
      * mark item blue 
      * if not 
      * mark item red 
      */ 

      return false; 
     } 
    }); 
} 

public void prepareListData() { 
    listDataHeader = new ArrayList<String>(); //category 
    listDataChild = new HashMap<String, List<String>>(); //ingredient 

    listDataHeader = db.getAllCategoryIngredientsName(); 

    List<String> tmp; 

    for (int i = 0; i < listDataHeader.size(); i++) { 
     tmp = db.getAllIngredientByCategory(listDataHeader.get(i)); 
     listDataChild.put(listDataHeader.get(i), tmp); 
    } 
} 

/* ... */ 

}

这是我的适配器:

public class ExpandableListAdapter extends BaseExpandableListAdapter { 

private Context _context; 
private List<String> category; 
private HashMap<String, List<String>> ingredient; 

public ExpandableListAdapter(Context context, List<String> category, 
          HashMap<String, List<String>> ingredient) { 
    this._context = context; 
    this.category = category; 
    this.ingredient = ingredient; 
} 

@Override 
public Object getChild(int groupPosition, int childPosititon) { 
    return this.ingredient.get(this.category.get(groupPosition)) 
      .get(childPosititon); 
} 

@Override 
public long getChildId(int groupPosition, int childPosition) { 
    return childPosition; 
} 

@Override 
public View getChildView(final int groupPosition, final int childPosition, 
         boolean isLastChild, View convertView, ViewGroup parent) { 

    if (convertView == null) { 
     LayoutInflater infalInflater = (LayoutInflater) this._context 
       .getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
     convertView = infalInflater.inflate(R.layout.exp_list_item, null); 
    } 

    final String childText = (String) getChild(groupPosition, childPosition); 

    TextView child = (TextView) convertView 
      .findViewById(R.id.lblListChild); 
    child.setText(childText); 

    return convertView; 
} 

@Override 
public int getChildrenCount(int groupPosition) { 
    return this.ingredient.get(this.category.get(groupPosition)) 
      .size(); 
} 

@Override 
public Object getGroup(int groupPosition) { 
    return this.category.get(groupPosition); 
} 

@Override 
public int getGroupCount() { 
    return this.category.size(); 
} 

@Override 
public long getGroupId(int groupPosition) { 
    return groupPosition; 
} 

@Override 
public View getGroupView(final int groupPosition, boolean isExpanded, 
         View convertView, ViewGroup parent) { 
    if (convertView == null) { 
     LayoutInflater infalInflater = (LayoutInflater) this._context 
       .getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
     convertView = infalInflater.inflate(R.layout.exp_list_group, null); 
    } 

    String headerTitle = (String) getGroup(groupPosition); 

    final TextView lblListHeader = (TextView) convertView 
      .findViewById(R.id.lblListHeader); 
    lblListHeader.setTypeface(null, Typeface.BOLD); 
    lblListHeader.setText(headerTitle); 

    return convertView; 
} 

@Override 
public boolean hasStableIds() { 
    return false; 
} 

@Override 
public boolean isChildSelectable(int groupPosition, int childPosition) { 
    return true; 
} 

}

而这里xml-files:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
xmlns:tools="http://schemas.android.com/tools" 
android:layout_width="match_parent" 
android:layout_height="match_parent" 
android:paddingBottom="@dimen/activity_vertical_margin" 
android:paddingLeft="@dimen/activity_horizontal_margin" 
android:paddingRight="@dimen/activity_horizontal_margin" 
android:paddingTop="@dimen/activity_vertical_margin" 
tools:context=".Ingredient.SelectIngredientByCategory" 
android:orientation="vertical"> 

<ExpandableListView 
    android:id="@+id/elvIngredientsByCategory" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:divider="#b5b5b5" 
    android:dividerHeight="1dp" 
    android:padding="1dp" 
    android:choiceMode="multipleChoice"/> 

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
android:orientation="vertical" 
android:layout_width="match_parent" 
android:layout_height="match_parent"> 

<TextView 
    android:id="@+id/lblListHeader" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:textSize="17dp" 
    android:textColor="#000000"/> 

</LinearLayout> 

    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
android:orientation="vertical" android:layout_width="match_parent" 
android:layout_height="match_parent"> 

<TextView 
    android:id="@+id/lblListChild" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:textSize="17dp"/> 

</LinearLayout> 

编辑:我发现我的问题的解决方案。感谢帮助。 :)

你可以设置背景颜色为选定的子视图

v.setBackgroundColor(Color.parseColor("#4482e5")); 
+0

谢谢您的回答。但是,如果用户选择了错误的成分,那又是什么?我已经尝试过这种方式,但我无法再将颜色更改为标准颜色。我用setSelected尝试了这一点,但它不起作用。我只能突出一个或多个项目。但取消选择不起作用...任何想法,我怎么能做到这一点? – maddy