public class RetrieveDataActivity extends Activity { private String[] columns={ContactsContract.Contacts._ID, ContactsContract.Contacts.DISPLAY_NAME, ContactsContract.CommonDataKinds.Phone.NUMBER, ContactsContract.CommonDataKinds.Phone.CONTACT_ID}; public void onCreate(Bundle savedInstanceState){ super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); TextView tv=(TextView) findViewById(R.id.result); tv.setText(getQueryData()); } private String getQueryData(){ StringBuilder sb=new StringBuilder(); ContentResolver resolver=getContentResolver(); Cursor cursor=resolver.query(ContactsContract.Contacts.CONTENT_URI,null,null,null,null); while (cursor.moveToNext()){ int idIndex=cursor.getColumnIndex(columns[0]); int displayNameIndex= cursor.getColumnIndex(columns[1]); int id=cursor.getInt(idIndex); String displayName=cursor.getString(displayNameIndex); Cursor phone= resolver.query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null,columns[3]+"="+id,null,null); while(phone.moveToNext()){ int phoneNumberIndex=phone.getColumnIndex(columns[2]); String phoneNumber=phone.getString(phoneNumberIndex); sb.append(displayName+":"+phoneNumber+"\n"); cursor.close(); } }

根据你提供的代码，我发现在第二个while循环中，没有关闭`phone`游标。这可能是导致无法查询出通讯录内容的原因之一。

另外，`cursor.close()`应该在第一个while循环的末尾处调用，而不是在第二个while循环的末尾处调用。因为第二个while循环是在第一个while循环的内部执行的，如果在第二个while循环中关闭了游标，那么第一个while循环将无法正常执行。

此外，我还注意到在查询电话号码时，`columns[3]`应该是`ContactsContract.CommonDataKinds.Phone.CONTACT_ID`，而不是`ContactsContract.CommonDataKinds.Phone.NUMBER`，因为`columns[3]`对应的是通讯录ID，而不是电话号码。

修改后的代码如下：

public class RetrieveDataActivity extends Activity {
    private String[] columns = {ContactsContract.Contacts._ID, ContactsContract.Contacts.DISPLAY_NAME, ContactsContract.CommonDataKinds.Phone.NUMBER, ContactsContract.CommonDataKinds.Phone.CONTACT_ID};

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        TextView tv = (TextView) findViewById(R.id.result);
        tv.setText(getQueryData());
    }

    private String getQueryData() {
        StringBuilder sb = new StringBuilder();
        ContentResolver resolver = getContentResolver();
        Cursor cursor = resolver.query(ContactsContract.Contacts.CONTENT_URI, null, null, null, null);
        while (cursor.moveToNext()) {
            int idIndex = cursor.getColumnIndex(columns[0]);
            int displayNameIndex = cursor.getColumnIndex(columns[1]);
            int id = cursor.getInt(idIndex);
            String displayName = cursor.getString(displayNameIndex);
            Cursor phone = resolver.query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null, columns[3] + "=" + id, null, null);
            while (phone.moveToNext()) {
                int phoneNumberIndex = phone.getColumnIndex(columns[2]);
                String phoneNumber = phone.getString(phoneNumberIndex);
                sb.append(displayName + ":" + phoneNumber + "\n");
            }
            phone.close();
        }
        cursor.close();
        return sb.toString();
    }
}

希望这可以帮到你。