Android Contact 导入导出 vcf格式（不依赖第三方库）

Android sdk 支持vcf处理的（忘记最低哪个版本开始支持的了，可以查一查）

备注：此代码来自Stack Overflow（原地址找不到了，o(╥﹏╥)o）

1. 导出联系人为vcf格式

Contact provider中有ContactsContract.Contacts.CONTENT_VCARD_URI的定义，说明他是支持vCard规范的

package com.mygmer.contactstest;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.ArrayList;

import android.app.Activity;
import android.content.res.AssetFileDescriptor;
import android.database.Cursor;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.ContactsContract;
import android.util.Log;

public class VCardActivity extends Activity {
    Cursor cursor;
    ArrayList<String> vCard;
    String vfile;

    /**
     * Called when the activity is first created.
     */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        vfile = "Contacts" + "_" + "mfTest" + ".vcf";
        /**This Function For Vcard And here i take one Array List in Which i store every Vcard String of Every Conatact
         * Here i take one Cursor and this cursor is not null and its count>0 than i repeat one loop up to cursor.getcount() means Up to number of phone contacts.
         * And in Every Loop i can make vcard string and store in Array list which i declared as a Global.
         * And in Every Loop i move cursor next and print log in logcat.
         * */
        getVcardString();

    }

    private void getVcardString() {
        // TODO Auto-generated method stub
        vCard = new ArrayList<String>();
        cursor = getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null, null, null, null);
        if (cursor != null && cursor.getCount() > 0) {
            cursor.moveToFirst();
            for (int i = 0; i < cursor.getCount(); i++) {

                get(cursor);
                Log.d("TAG", "Contact " + (i + 1) + "VcF String is" + vCard.get(i));
                cursor.moveToNext();
            }

        } else {
            Log.d("TAG", "No Contacts in Your Phone");
        }

    }

    public void get(Cursor cursor) {

        //cursor.moveToFirst();
        String lookupKey = cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts.LOOKUP_KEY));
        Uri uri = Uri.withAppendedPath(ContactsContract.Contacts.CONTENT_VCARD_URI, lookupKey);
        AssetFileDescriptor fd;
        try {
            fd = this.getContentResolver().openAssetFileDescriptor(uri, "r");

            // Your Complex Code and you used function without loop so how can you get all Contacts Vcard.??

           /* FileInputStream fis = fd.createInputStream();
            byte[] buf = new byte[(int) fd.getDeclaredLength()];
            fis.read(buf);
            String VCard = new String(buf);
            String path = Environment.getExternalStorageDirectory().toString() + File.separator + vfile;
            FileOutputStream out = new FileOutputStream(path);
            out.write(VCard.toString().getBytes());
            Log.d("Vcard",  VCard);*/

            FileInputStream fis = fd.createInputStream();
            byte[] buf = new byte[(int) fd.getDeclaredLength()];
            fis.read(buf);
            String vcardstring = new String(buf);
            vCard.add(vcardstring);

            String storage_path = Environment.getExternalStorageDirectory().toString() + File.separator + vfile;
            FileOutputStream mFileOutputStream = new FileOutputStream(storage_path, false);
            mFileOutputStream.write(vcardstring.toString().getBytes());

        } catch (Exception e1) {
            // TODO Auto-generated catch block
            e1.printStackTrace();
        }
    }
}

2.导入vcf格式联系人

　Example code：

Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.fromFile(new File("/storage/sdcard0/contacts_20180106150125.vcf")),"text/x-vcard");
startActivity(intent);

关于Intent.ACTION_VIEW的描述，里面举例就是举的Contact，嘿嘿：

 /**
     * Activity Action: Display the data to the user.  This is the most common
     * action performed on data -- it is the generic action you can use on
     * a piece of data to get the most reasonable thing to occur.  For example,
     * when used on a contacts entry it will view the entry; when used on a
     * mailto: URI it will bring up a compose window filled with the information
     * supplied by the URI; when used with a tel: URI it will invoke the
     * dialer.
     * <p>Input: {@link #getData} is URI from which to retrieve data.
     * <p>Output: nothing.
     */

由上面的描述猜测，还原过程中会弹出提示框（会不会有啥确认按钮？），在Android5.1测试，有弹出窗，但没确认按钮，支持就导入联系人了。其他高版本未测试过