作为一个小型学校项目，我试图为Android创建一个非常简单的导出应用程序。 首先，我想要导出的是联系人列表 - 然后将其导入另一个设备。 我有两个用于测试的设备 - 一个运行2.2.3，另一个运行4.0.4。
我一直在使用以下代码来完成获取联系人信息，然后将XML文件保存到外部存储：
package com.example.contacts;
import java.util.ArrayList;
import android.os.Bundle;
import android.provider.ContactsContract;
import android.app.Activity;
import android.content.ContentResolver;
import android.database.Cursor;
import android.util.Log;
import android.view.Menu;
public class MainActivity extends Activity {
String num = "nope";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
GetContacts();
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public String GetContacts() {
ContentResolver cr = getContentResolver();
Cursor cur = cr.query(ContactsContract.Contacts.CONTENT_URI,
null, null, null, null);
if (cur.getCount() > 0) {
while (cur.moveToNext()) {
String id = cur.getString(cur.getColumnIndex(ContactsContract.Contacts._ID));
String con = cur.getString(cur.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME));
if (Integer.parseInt(cur.getString(
cur.getColumnIndex(ContactsContract.Contacts.HAS_PHONE_NUMBER))) > 0) {
Cursor pCur = cr.query(
ContactsContract.CommonDataKinds.Phone.CONTENT_URI,
null,
ContactsContract.CommonDataKinds.Phone.CONTACT_ID +" = ?",
new String[]{id}, null);
while (pCur.moveToNext()) {
String num = pCur.getString(pCur.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
Log.d("Contacts: ", "Name: " + con + ", Number: " + num);
return num;
}
pCur.close();
}
}
}
return num;
}
}
此代码成功将我的联系人打印到日志中。
下一个代码只是在设备的外部存储（SD卡）上创建一个XML文件 - 取自http://www.anddev.org/write_a_simple_xml_file_in_the_sd_card_using_xmlserializer-t8350.html：
package com.example.contacts;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import org.xmlpull.v1.XmlSerializer;
import android.app.Activity;
import android.os.Bundle;
import android.os.Environment;
import android.util.Log;
import android.util.Xml;
import android.widget.TextView;
public class XmlFileCreator extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
//create a new file called "new.xml" in the SD card
File newxmlfile = new File(Environment.getExternalStorageDirectory()+"/new.xml");
try{
newxmlfile.createNewFile();
}catch(IOException e){
Log.e("IOException", "exception in createNewFile() method");
}
//we have to bind the new file with a FileOutputStream
FileOutputStream fileos = null;
try{
fileos = new FileOutputStream(newxmlfile);
}catch(FileNotFoundException e){
Log.e("FileNotFoundException", "can't create FileOutputStream");
}
//we create a XmlSerializer in order to write xml data
XmlSerializer serializer = Xml.newSerializer();
try {
//we set the FileOutputStream as output for the serializer, using UTF-8 encoding
serializer.setOutput(fileos, "UTF-8");
//Write <?xml declaration with encoding (if encoding not null) and standalone flag (if standalone not null)
serializer.startDocument(null, Boolean.valueOf(true));
//set indentation option
serializer.setFeature("http://xmlpull.org/v1/doc/features.html#indent- output", true);
//start a tag called "root"
serializer.startTag(null, "root");
//i indent code just to have a view similar to xml-tree
serializer.startTag(null, "child1");
serializer.endTag(null, "child1");
serializer.startTag(null, "child2");
//set an attribute called "attribute" with a "value" for <child2>
serializer.attribute(null, "attribute", "value");
serializer.endTag(null, "child2");
serializer.startTag(null, "child3");
//write some text inside <child3>
serializer.text("some text inside child3");
serializer.endTag(null, "child3");
serializer.endTag(null, "root");
serializer.endDocument();
//write xml data into the FileOutputStream
serializer.flush();
//finally we close the file stream
fileos.close();
TextView tv = (TextView)this.findViewById(R.id.result);
tv.setText("file has been created on SD card");
} catch (Exception e) {
Log.e("Exception","error occurred while creating xml file");
}
}
}
现在，我的问题如下： 如何继续将联系人字符串添加到XML文件？ 我想我必须添加这样的标签：
starttag：联系人 starttag：名称：endtag starttag：Number：endtag ：endtag
但是如何将这些联系人详细信息写入第一个＆＃34;联系人的子标签中？标签？ 任何参考都很可爱。