getItemAtPosition() 如何从 ListView 中的选定项获取可读数据

Question

我有一个从 Android ContactManager 示例中获取的联系人列表视图。该列表显示正常，但我不知道如何从所选项目中获取信息，例如“姓名”和“电话号码”。

我可以获得选定的位置，但 mContactList.getItemAtPosition(position) 的结果是 ContentResolver$CursorWrapperInner ，这对我来说没有任何意义。我无法从中得到正面或反面。

有人知道如何从列表视图中的所选项目中获取姓名/ID/电话号码吗？

这是我的代码。

@Override
public void onCreate(Bundle savedInstanceState)
{
    Log.v(TAG, "Activity State: onCreate()");
    super.onCreate(savedInstanceState);
    setContentView(R.layout.choose_contact);

    // Obtain handles to UI objects
    mAddAccountButton = (Button) findViewById(R.id.addContactButton);
    mContactList = (ListView) findViewById(R.id.contactList);
    mShowInvisibleControl = (CheckBox) findViewById(R.id.showInvisible);

    // Initialize class properties
    mShowInvisible = false;
    mShowInvisibleControl.setChecked(mShowInvisible);
    mContactList.setOnItemClickListener(new OnItemClickListener()
    {
      public void onItemClick(AdapterView<?> parent, View view, int position, long id)
      {
       addContactAt(position);
      }
    });
    mShowInvisibleControl.setOnCheckedChangeListener(new OnCheckedChangeListener() {
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
            Log.d(TAG, "mShowInvisibleControl changed: " + isChecked);
            mShowInvisible = isChecked;
            populateContactList();
        }
    });

    // Populate the contact list
    populateContactList();

}

/**
 * Populate the contact list based on account currently selected in the account spinner.
 */
private SimpleCursorAdapter adapter;
private void populateContactList() {
    // Build adapter with contact entries
    Cursor cursor = getContacts();
    String[] fields = new String[] {
            ContactsContract.Data.DISPLAY_NAME
    };
    adapter = new SimpleCursorAdapter(this, R.layout.contact_entry, cursor,
            fields, new int[] {R.id.contactEntryText});
    mContactList.setAdapter(adapter);
}

/**
 * Obtains the contact list for the currently selected account.
 *
 * @return A cursor for for accessing the contact list.
 */
private Cursor getContacts()
{
    // Run query
    Uri uri = ContactsContract.Contacts.CONTENT_URI;
    String[] projection = new String[] {
            ContactsContract.Contacts._ID,
            ContactsContract.Contacts.DISPLAY_NAME
    };
    String selection = ContactsContract.Contacts.IN_VISIBLE_GROUP + " = '" +
            (mShowInvisible ? "0" : "1") + "'";
    String[] selectionArgs = null;
    String sortOrder = ContactsContract.Contacts.DISPLAY_NAME + " COLLATE LOCALIZED ASC";

    return managedQuery(uri, projection, selection, selectionArgs, sortOrder);
}

private void addContactAt(int position)
{
 Object o = mContactList.getItemAtPosition(position);
}

}`

Answer 1

@Override
protected void onListItemClick(ListView l, View v, int position, long ida) {
   super.onListItemClick(l, v, position, ida);

   Cursor mycursor = (Cursor) getListView().getItemAtPosition(position);
   showToast("mycursor.getString(1) " + mycursor.getString(1) +"   ");

Answer 2

繁荣！我想通了。基本上，您可以从单击事件中获取位置编号，然后在我的 addContatAt() 中使用该位置在光标内搜索所需的字段。就我而言，我想要显示名称。

我习惯在 Flex 中做事，所以这个 Cursor 业务对我来说是不同的:)

不管怎样，对于其他人来说，这是我的代码：

@Override
public void onCreate(Bundle savedInstanceState)
{
    Log.v(TAG, "Activity State: onCreate()");
    super.onCreate(savedInstanceState);
    setContentView(R.layout.choose_contact);

    // Obtain handles to UI objects
    mAddAccountButton = (Button) findViewById(R.id.addContactButton);
    mContactList = (ListView) findViewById(R.id.contactList);
    mShowInvisibleControl = (CheckBox) findViewById(R.id.showInvisible);

    // Initialize class properties
    mShowInvisible = false;
    mShowInvisibleControl.setChecked(mShowInvisible);
    mContactList.setOnItemClickListener(new OnItemClickListener()
    {
         public void onItemClick(AdapterView<?> parent, View view, int position, long id)
         {
             addContactAt(position);
         }
    });
    mShowInvisibleControl.setOnCheckedChangeListener(new OnCheckedChangeListener() {
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
            Log.d(TAG, "mShowInvisibleControl changed: " + isChecked);
            mShowInvisible = isChecked;
            populateContactList();
        }
    });

    // Populate the contact list
    populateContactList();

}

/**
 * Populate the contact list based on account currently selected in the account spinner.
 */
private SimpleCursorAdapter adapter;
private void populateContactList() {
    // Build adapter with contact entries
    contactsCursor = getContacts();
    String[] fields = new String[] {
            ContactsContract.Data.DISPLAY_NAME
    };
    adapter = new SimpleCursorAdapter(this, R.layout.contact_entry, contactsCursor,
            fields, new int[] {R.id.contactEntryText});
    mContactList.setAdapter(adapter);
}

/**
 * Obtains the contact list for the currently selected account.
 *
 * @return A cursor for for accessing the contact list.
 */
private Cursor getContacts()
{
    // Run query
    Uri uri = ContactsContract.Contacts.CONTENT_URI;
    String[] projection = new String[] {
            ContactsContract.Contacts._ID,
            ContactsContract.Contacts.DISPLAY_NAME
    };
    String selection = ContactsContract.Contacts.IN_VISIBLE_GROUP + " = '" +
            (mShowInvisible ? "0" : "1") + "'";
    String[] selectionArgs = null;
    String sortOrder = ContactsContract.Contacts.DISPLAY_NAME + " COLLATE LOCALIZED ASC";

    return managedQuery(uri, projection, selection, selectionArgs, sortOrder);
}

private void addContactAt(int position)
{
    contactsCursor.moveToPosition(position);
    String name = contactsCursor.getString(
            contactsCursor.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME));
}
}

Answer 3

public void onItemClick(AdapterView<?> parent, View view,int position, long id) 
{
Map<String, Object> map = (Map<String, Object>)_productListView.getItemAtPosition(position); 
String _productCode = (String) map.get("ProductCode");
String _productName = (String) map.get("ProjectName");
Double _price = (Double) map.get("Price");
}

Answer 4

嗯 - 你把 AdapterView 的光标弄乱了，这可能并不总是一个好主意。另一种方法是在 onItemClick 处理程序中调用 Parent.getItemAtPosition(position) 并将结果转换为 Cursor；它将指向与所单击的项目相对应的行。

Answer 5

我使用了 Miki Habryn 提到的以下代码

    public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
    Cursor client = (Cursor)parent.getItemAtPosition(position);
    String client_name = client.getString(2); // third column in db
    Toast.makeText(getBaseContext(), client_name, Toast.LENGTH_SHORT).show();
}