消除加载联系人时的时间复杂度

Question

这是我在 android 中检索电话联系人的代码。该应用程序在加载联系人时需要很多时间。我使用了嵌套循环，因此需要很长时间，请告诉我一个更好的方法来实现同样的效果。

@Override
        protected Cursor doInBackground(Void... params) {
            Uri contactsUri = ContactsContract.Contacts.CONTENT_URI;
 
            // Querying the table ContactsContract.Contacts to retrieve all the contacts
            Cursor contactsCursor = getContentResolver().query(contactsUri, null, null, null,
            ContactsContract.Contacts.DISPLAY_NAME + " ASC ");
 
            if(contactsCursor.moveToFirst()){
                do{
                    long contactId = contactsCursor.getLong(contactsCursor.getColumnIndex("_ID"));
 
                    Uri dataUri = ContactsContract.Data.CONTENT_URI;
 
                    // Querying the table ContactsContract.Data to retrieve individual items like
                    // home phone, mobile phone, work email etc corresponding to each contact
                    Cursor dataCursor = getContentResolver().query(dataUri, null,
                                        ContactsContract.Data.CONTACT_ID + "=" + contactId,
                                        null, null);
 
                    String displayName="";
                    String nickName="";
                    String homePhone="";
                    String mobilePhone="";
                    String workPhone="";
                    String photoPath="" + R.drawable.blank;
                    byte[] photoByte=null;
                    String homeEmail="";
                    String workEmail="";
                    String companyName="";
                    String title="";
 
                    if(dataCursor.moveToFirst()){
                        // Getting Display Name
                        displayName = dataCursor.getString(dataCursor.getColumnIndex(ContactsContract.Data.DISPLAY_NAME ));
                        do{
 
                            // Getting NickName
                            if(dataCursor.getString(dataCursor.getColumnIndex("mimetype")).equals(ContactsContract.CommonDataKinds.Nickname.CONTENT_ITEM_TYPE))
                                nickName = dataCursor.getString(dataCursor.getColumnIndex("data1"));
 
                            // Getting Phone numbers
                            if(dataCursor.getString(dataCursor.getColumnIndex("mimetype")).equals(ContactsContract.CommonDataKinds.Phone.CONTENT_ITEM_TYPE)){
                                switch(dataCursor.getInt(dataCursor.getColumnIndex("data2"))){
                                    case ContactsContract.CommonDataKinds.Phone.TYPE_HOME :
                                        homePhone = dataCursor.getString(dataCursor.getColumnIndex("data1"));
                                        break;
                                    case ContactsContract.CommonDataKinds.Phone.TYPE_MOBILE :
                                        mobilePhone = dataCursor.getString(dataCursor.getColumnIndex("data1"));
                                        break;
                                    case ContactsContract.CommonDataKinds.Phone.TYPE_WORK :
                                        workPhone = dataCursor.getString(dataCursor.getColumnIndex("data1"));
                                        break;
                                }
                            }
 
                            // Getting EMails
                            if(dataCursor.getString(dataCursor.getColumnIndex("mimetype")).equals(ContactsContract.CommonDataKinds.Email.CONTENT_ITEM_TYPE ) ) {
                                switch(dataCursor.getInt(dataCursor.getColumnIndex("data2"))){
                                    case ContactsContract.CommonDataKinds.Email.TYPE_HOME :
                                        homeEmail = dataCursor.getString(dataCursor.getColumnIndex("data1"));
                                        break;
                                    case ContactsContract.CommonDataKinds.Email.TYPE_WORK :
                                        workEmail = dataCursor.getString(dataCursor.getColumnIndex("data1"));
                                        break;
                                }
                            }
 
                            // Getting Organization details
                            if(dataCursor.getString(dataCursor.getColumnIndex("mimetype")).equals(ContactsContract.CommonDataKinds.Organization.CONTENT_ITEM_TYPE)){
                                companyName = dataCursor.getString(dataCursor.getColumnIndex("data1"));
                                title = dataCursor.getString(dataCursor.getColumnIndex("data4"));
                            }
 
                            // Getting Photo
                            if(dataCursor.getString(dataCursor.getColumnIndex("mimetype")).equals(ContactsContract.CommonDataKinds.Photo.CONTENT_ITEM_TYPE)){
                                photoByte = dataCursor.getBlob(dataCursor.getColumnIndex("data15"));
 
                                if(photoByte != null) {
                                    Bitmap bitmap = BitmapFactory.decodeByteArray(photoByte, 0, photoByte.length);
 
                                    // Getting Caching directory
                                    File cacheDirectory = getBaseContext().getCacheDir();
 
                                    // Temporary file to store the contact image
                                    File tmpFile = new File(cacheDirectory.getPath() + "/wpta_"+contactId+".png");
 
                                    // The FileOutputStream to the temporary file
                                    try {
                                        FileOutputStream fOutStream = new FileOutputStream(tmpFile);
 
                                        // Writing the bitmap to the temporary file as png file
                                        bitmap.compress(Bitmap.CompressFormat.PNG,100, fOutStream);
 
                                        // Flush the FileOutputStream
                                        fOutStream.flush();
 
                                        //Close the FileOutputStream
                                        fOutStream.close();
 
                                    } catch (Exception e) {
                                        e.printStackTrace();
                                    }
                                    photoPath = tmpFile.getPath();
                                }
                            }
                        }while(dataCursor.moveToNext());
                        String details = "";
 
                        // Concatenating various information to single string
                        if(homePhone != null && !homePhone.equals("") )
                            details = "HomePhone : " + homePhone + "\n";
                        if(mobilePhone != null && !mobilePhone.equals("") )
                            details += "MobilePhone : " + mobilePhone + "\n";
                        if(workPhone != null && !workPhone.equals("") )
                            details += "WorkPhone : " + workPhone + "\n";
                        if(nickName != null && !nickName.equals("") )
                            details += "NickName : " + nickName + "\n";
                        if(homeEmail != null && !homeEmail.equals("") )
                            details += "HomeEmail : " + homeEmail + "\n";
                        if(workEmail != null && !workEmail.equals("") )
                            details += "WorkEmail : " + workEmail + "\n";
                        if(companyName != null && !companyName.equals("") )
                            details += "CompanyName : " + companyName + "\n";
                        if(title != null && !title.equals("") )
                            details += "Title : " + title + "\n";
 
                        // Adding id, display name, path to photo and other details to cursor
                        mMatrixCursor.addRow(new Object[]{ Long.toString(contactId),displayName,photoPath,details});
                    }
                }while(contactsCursor.moveToNext());
            }
            return mMatrixCursor;
        }
 

Answer 1

我有同样的问题，我已经通过使用 ContactsContract.CommonDataKinds.Phone 类解决了。

这是我的联系方式。你可以试试

public void fetchContacts2() {
        contactArrayList = new ArrayList<>();
        try {
            Uri uri = ContactsContract.CommonDataKinds.Phone.CONTENT_URI;
            Cursor cursor = context.getContentResolver().query(uri,
                    new String[] {ContactsContract.CommonDataKinds.Phone.NUMBER,
                            ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME,
                            ContactsContract.CommonDataKinds.Phone._ID,
                            ContactsContract.CommonDataKinds.Phone.HAS_PHONE_NUMBER},
                    null,
                    null,
                    null);
            Map<String,contact> contactMap = new HashMap<>();
            if (cursor.getCount() > 0) {
                cursor.moveToFirst();
                while (!cursor.isAfterLast()) {

                    String contact_id = cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone._ID));
                    String basename = cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));
                    String name = null;

                    if (basename != null) {
                        try {
                            name = new String(basename.getBytes("UTF-8"));
                        } catch (UnsupportedEncodingException e) {
                            e.printStackTrace();
                        }
                    }
                    long hasPhoneNumber = Long.parseLong(cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.HAS_PHONE_NUMBER)));
                    if (hasPhoneNumber > 0) {
                        String number = cursor.getString(cursor.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
                        if (name != null && number != null && ! contactMap.containsKey(number)) {
                            contact c = new contact(context);
                            c.contactid = contact_id;
                            c.name = name;
                            c.phonenr = number;
                            c.setsearchphone();
                            c.email = "";
                            contactMap.put(number,c);
                        }
                    }
                    cursor.moveToNext();
                }
                cursor.close();
                if (contactMap != null){
                    contactArrayList.addAll(contactMap.values());
                }
            } else {
//          Toast.makeText(context, "No contacts Found", Toast.LENGTH_LONG).show();
            }
        } catch (Exception e) {
            e.printStackTrace();
            Log.v("Contacts", "getin " + e.getMessage());
        }
        Log.v("Contacts", "finished getting contacts in mem");

    }