android - 是否可以在 listView 上禁用滚动？

Question

我动态地将项目添加到 aListView并希望使所有项目始终可见，而无需滚动。

布局代码：

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

<ScrollView
    android:layout_width="match_parent"
    android:layout_height="wrap_content" >

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

        <ImageView
            android:id="@+id/imageView1"
            android:layout_width="match_parent"
            android:layout_height="16dp"
            android:src="@drawable/head_cella" />

        <TextView
            android:id="@+id/textView1"
            android:layout_width="wrap_content"
            android:layout_height="41dp"
            android:background="@drawable/body_cella"
            android:gravity="center_horizontal"
            android:paddingTop="5dp"
            android:text="Remember to save before leaving this page or inserted/modified data will be lost."
            android:textColor="#000000"
            android:textSize="13dp" />

        <ImageView
            android:id="@+id/ImageView01"
            android:layout_width="match_parent"
            android:layout_height="16dp"
            android:layout_marginTop="30dp"
            android:src="@drawable/head_cella" />

        <TextView
            android:id="@+id/TextView01"
            android:layout_width="wrap_content"
            android:layout_height="35dp"
            android:background="@drawable/body_cella"
            android:gravity="center_horizontal"
            android:paddingTop="10dp"
            android:text="Category"
            android:textColor="#000000"
            android:textSize="15dp" />

        <Spinner
            android:id="@+id/category_spinner"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />

        <ImageView
            android:id="@+id/ImageView02"
            android:layout_width="match_parent"
            android:layout_height="16dp"
            android:layout_marginTop="30dp"
            android:src="@drawable/head_cella" />

        <TextView
            android:id="@+id/TextView02"
            android:layout_width="wrap_content"
            android:layout_height="35dp"
            android:background="@drawable/body_cella"
            android:gravity="center_horizontal"
            android:paddingTop="10dp"
            android:text="Name"
            android:textColor="#000000"
            android:textSize="15dp" />

        <EditText
            android:id="@+id/recipe_title"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:ems="10"
            android:hint="Recipe title" android:lines="1"/>

        <ImageView
            android:id="@+id/ImageView03"
            android:layout_width="match_parent"
            android:layout_height="16dp"
            android:layout_marginTop="30dp"
            android:src="@drawable/head_cella" />

        <TextView
            android:id="@+id/TextView03"
            android:layout_width="wrap_content"
            android:layout_height="35dp"
            android:background="@drawable/body_cella"
            android:gravity="center_horizontal"
            android:paddingTop="10dp"
            android:text="Ingredients"
            android:textColor="#000000"
            android:textSize="15dp" />
         <ListView
            android:id="@android:id/list"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1" android:cacheColorHint="#00000000" android:divider="#00000000"
            android:isScrollContainer="false"
            >
       </ListView>

         <Button
             android:id="@+id/button_ing"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:text="" android:background="@drawable/add_recipe_button" android:onClick="addItems"/>

    </LinearLayout>

</ScrollView></LinearLayout>

旧的 OnCreate() 函数代码：

protected void onCreate(Bundle savedInstanceState)
{

    super.onCreate(savedInstanceState);

    setContentView(R.layout.add_recipe_form);

    spinner = (Spinner)myhead.findViewById(R.id.category_spinner);

    Cursor cursor = mydb.getCategoriesList();
    ArrayList<Category> list = new ArrayList<Category>();
    list.add(new Category(0,"Choose a category"));

    while (cursor.moveToNext()) {
        list.add(new Category(cursor.getInt(0),cursor.getString(1))); 
    }
    // Step 2: Create and fill an ArrayAdapter with a bunch of "State" objects
    ArrayAdapter spinnerArrayAdapter = new ArrayAdapter(this,android.R.layout.simple_spinner_item, list);

    // Step 3: Tell the spinner about our adapter
    spinner.setAdapter(spinnerArrayAdapter);   
    spinner.setOnItemSelectedListener(this);


    setListAdapter(adapter);
    ingredients.add((View)findViewById(R.layout.row_add_recipe));
    adapter.notifyDataSetChanged();
}

如果我移动与用数据库数据填充微调器相关的代码，它总是返回 NullPointerException，因为在我的布局中找不到它。所以我需要把它放在这里，将 addHeaderView() 添加到我的 ListView 的解决方案似乎没问题，但我有另一个关于我的头部布局的 NullPointerException：

protected void onCreate(Bundle savedInstanceState)
{

    super.onCreate(savedInstanceState);

    setContentView(R.layout.add_recipe_form);
    ListView mylistview = (ListView) findViewById(android.R.id.list);
    LinearLayout myhead = (LinearLayout)findViewById(R.id.linear_form);
    mylistview.addHeaderView(myhead);
    spinner = (Spinner)myhead.findViewById(R.id.category_spinner);

    Cursor cursor = mydb.getCategoriesList();
    ArrayList<Category> list = new ArrayList<Category>();
    list.add(new Category(0,"Choose a category"));

    while (cursor.moveToNext()) {
        list.add(new Category(cursor.getInt(0),cursor.getString(1))); 
    }
    // Step 2: Create and fill an ArrayAdapter with a bunch of "State" objects
    ArrayAdapter spinnerArrayAdapter = new ArrayAdapter(this,android.R.layout.simple_spinner_item, list);

    // Step 3: Tell the spinner about our adapter
    spinner.setAdapter(spinnerArrayAdapter);   
    spinner.setOnItemSelectedListener(this);


    setListAdapter(adapter);
    ingredients.add((View)findViewById(R.layout.row_add_recipe));
    adapter.notifyDataSetChanged();
}

Answer 1

如果我理解你，你只需要更多的视图，这些视图可以与你的列表视图一起滚动。实现它的最佳方法是addHeaderView()在addFooterView()您的ListView().

编辑：

它应该是这样的，我认为：

@Override
public void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.your_main_layout);
    LayoutInflater inflater = (LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View header = inflater.inflate(R.layout.your_header_layout); //R.layout, not R.id!

    (ListView) list = findViewById(android.R.list);
    list.addHeaderView(header);

    list.setAdapter(adapter); //according to docs you should call setAdapter() after addHeaderView()

    //to get the spinner
    (Spinner) spinner = (Spinner) header.findViewById(R.id.spinner);

}

我是凭记忆写的，没有测试它，但我认为它应该可以工作。有空的时候试试看。

Answer 2

一种解决方案是将 ListView 的高度设置为与内容一样大。您可以使用以下类而不是 ListView 来实现此效果：

public class ExpandedListView extends ListView {

  private int old_count = 0;

  public ExpandedListView(Context context, AttributeSet attrs) {
    super(context, attrs);
  }

  @Override
  protected void onDraw(Canvas canvas) {
    if (getCount() != old_count) {
        old_count = getCount();
        int totalHeight = 0;
        int desiredWidth = MeasureSpec.makeMeasureSpec(getWidth(), MeasureSpec.AT_MOST);
        for (int i = 0; i < getCount(); i++) {
            View listItem = getAdapter().getView(i, null, this);
            listItem.measure(desiredWidth, MeasureSpec.UNSPECIFIED);
            totalHeight += listItem.getMeasuredHeight();
        }

        ViewGroup.LayoutParams params = getLayoutParams();
        params.height = totalHeight + (getDividerHeight() * (getCount() - 1));
        setLayoutParams(params);
        requestLayout();
    }

    super.onDraw(canvas);
  }

}

无论如何，在 ScrollView 中有一个 ListView 是个坏主意，所以我会使用方法 addHeaderView() 和 addFooterView() 将布局中的其他元素添加为页眉/页脚视图，正如 MichałK 指出的那样。

这里有一个关于如何使用这些方法的示例：

https://github.com/commonsguy/cw-advandroid/tree/master/ListView/HeaderFooter

Answer 3

让你的ListView 身高大于你的内容大小。

假设您有5 个列表项，每个列表项的高度为20sp，将列表视图高度设置为 100 或更大 ，这样您就可以实现它