无法在颤振应用程序中使用contacts_service添加联系人答案

【问题标题】：Not able to add contact using contacts_service in flutter app无法在颤振应用程序中使用contacts_service添加联系人
【发布时间】：2020-09-17 17:28:59
【问题描述】：

实际上，我正在构建一个读卡器应用程序，其中数据来自 ML 模型并存储在 mycontrollers 函数中。但是在使用 ContactsService.addContact(contact);我收到错误。虽然联系人保存在应用程序中，但没有保存在手机的联系人列表中。

代码：

 void saveContactInPhone() {
try {

  print("saving Conatct");
  Contact contact = Contact();
    print("fi");
    contact.displayName = myController1.text ; 
    contact.phones = [Item(label: "mobile", value: myController4.text)];
    // contact.emails = [Item(label: "email", value: myController3.text)];
    contact.company = myController2.text;
    print("fi2");

  ContactsService.addContact(contact);
  print("object");      

} catch (e) {
  print(e);
}

}

错误：

I/flutter ( 1615): form init

我/颤振（1615）：/data/user/0/com.example.camera_app/app_flutter/2020-05-29 23:35:12.398628.png 我/颤动（1615）：图像我/颤振（1615）：404 I/颤动（1615）：图像发送我/颤振（1615）：形式来听单接触我/颤振（1615）：保存我/颤动（1615）：fi 我/颤动（1615）：fi2 我/颤动（1615）：对象 E/flutter（1615）：[错误：flutter/lib/ui/ui_dart_state.cc（157）]未处理的异常：FormatException：无效的信封 E/flutter (1615): #0 StandardMethodCodec.decodeEnvelope (package:flutter/src/services/message_codecs.dart:571:7) E/flutter（1615）：#1 MethodChannel._invokeMethod（包：flutter/src/services/platform_channel.dart:156:18） E/颤动（1615）： E/flutter（1615）：#2 MethodChannel.invokeMethod（包：flutter/src/services/platform_channel.dart:329:12） E/flutter (1615):#3 ContactsService.addContact (package:contacts_service/contacts_service.dart:83:16) E/颤振（1615）：#4 _FormState.saveData（包：camera_app/screens/form.dart:249:23） E/flutter（1615）：#5 _InkResponseState._handleTap（包：flutter/src/material/ink_well.dart:779:19） E/颤振（1615）：#6 _InkResponseState.build。（包：flutter/src/material/ink_well.dart:862:36） E/flutter（1615）：#7 GestureRecognizer.invokeCallback（包：flutter/src/gestures/recognizer.dart:182:24） E/flutter（1615）：#8 TapGestureRecognizer.handleTapUp（包：flutter/src/gestures/tap.dart:504:11） E/flutter（1615）：#9 BaseTapGestureRecognizer._checkUp（包：flutter/src/gestures/tap.dart:282:5） E/flutter (1615): #10 BaseTapGestureRecognizer.handlePrimaryPointer (package:flutter/src/gestures/tap.dart:217:7) E/flutter（1615）：#11 PrimaryPointerGestureRecognizer.handleEvent（包：flutter/src/gestures/recognizer.dart:475:9） E/flutter（1615）：#12 PointerRouter._dispatch（包：flutter/src/gestures/pointer_router.dart:76:12） E/颤振（1615）：#13 PointerRouter._dispatchEventToRoutes。（包：flutter/src/gestures/pointer_router.dart:122:9） E/flutter (1615): #14 _LinkedHashMapMixin.forEach (dart:collection-patch/compact_hash.dart:379:8) E/flutter（1615）：#15 PointerRouter._dispatchEventToRoutes（包：flutter/src/gestures/pointer_router.dart:120:18） E/flutter (1615): #16 PointerRouter.route (package:flutter/src/gestures/pointer_router.dart:106:7) E/flutter（1615）：#17 GestureBinding.handleEvent（包：flutter/src/gestures/binding.dart:218:19） E/flutter（1615）：#18 GestureBinding.dispatchEvent（包：flutter/src/gestures/binding.dart:198:22） E/flutter（1615）：#19 GestureBinding._handlePointerEvent（包：flutter/src/gestures/binding.dart:156:7） E/flutter（1615）：#20 GestureBinding._flushPointerEventQueue（包：flutter/src/gestures/binding.dart:102:7） E/flutter (1615): #21 GestureBinding._handlePointerDataPacket (package:flutter/src/gestures/binding.dart:86:7)

【问题讨论】：

标签： flutter dart

【解决方案1】：

实际上我错过了权限部分。哦，我是 Flutter 的新手。

这最终对我有用，可以将联系人保存在 MAin Contacts 或电话目录中。

所以让我们使用contacts_service 0.4.6。首先，添加依赖为：

dependencies:  
contacts_service: ^0.4.6

权限：

对于安卓将以下权限添加到您的 AndroidManifest.xml：

<uses-permission android:name="android.permission.READ_CONTACTS" />  
<uses-permission android:name="android.permission.WRITE_CONTACTS" />

对于 iOS 在 Info.plist 文件中设置 NSContactsUsageDescription

<key>NSContactsUsageDescription</key>  
<string>This app requires contacts access to function properly.</string>

导入库：

import 'package:contacts_service/contacts_service.dart';

基本上，

 final myController1 = TextEditingController();
 final myController2 = TextEditingController();
 ...

这些是用于存储用户在 Textfield 或 Textform 中输入的值的变量。该值可以通过myController1.text查询我们还可以将 Contact 类对象存储为：

   newContact.givenName = "Some name";
            newContact.emails = [
              Item(label: "email", value: "abc@gmail.com")
            ];
            newContact.company = myController2.text;
            newContact.phones = [
              Item(label: "mobile", value: "123456789")
            ];

仅保存联系人的代码：

     Future<void> saveContactInPhone() async {
    try {

      print("saving Conatct");
      PermissionStatus permission = await Permission.contacts.status;

    if (permission != PermissionStatus.granted) {
      await Permission.contacts.request();
      PermissionStatus permission = await Permission.contacts.status;

      if (permission == PermissionStatus.granted) {
        Contact newContact = new Contact();
        newContact.givenName = myController1.text;
        newContact.emails = [
          Item(label: "email", value: myController3.text)
        ];
        newContact.company = myController2.text;
        newContact.phones = [
          Item(label: "mobile", value: myController4.text)
        ];
        newContact.postalAddresses = [
          PostalAddress(region: myController6.text)
        ];
        await ContactsService.addContact(newContact);

      } else {
        //_handleInvalidPermissions(context);
      }
    } else {
      Contact newContact = new Contact();
        newContact.givenName = myController1.text;
        newContact.emails = [
          Item(label: "email", value: myController3.text)
        ];
        newContact.company = myController2.text;
        newContact.phones = [
          Item(label: "mobile", value: myController4.text)
        ];
        newContact.postalAddresses = [
          PostalAddress(region: myController6.text)
        ];
        await ContactsService.addContact(newContact);
    }
      print("object");      

    } catch (e) {
      print(e);
    }
  }

同样，我发现在实际电话目录中反映更改也很困难。所以我想出了这个解决方案：

Future<void> saveContactInPhone() async {
    try {
      print("saving Conatct");
      PermissionStatus permission = await Permission.contacts.status;

      if (permission != PermissionStatus.granted) {
        await Permission.contacts.request();
        PermissionStatus permission = await Permission.contacts.status;

        if (permission == PermissionStatus.granted) {
          if (widget.checkPrev == 'for_edit') {
            // Contact updatedContact = new Contact();
            Iterable<Contact> updatedContact =
                await ContactsService.getContacts(query: myController1.text);

            Contact updatedContact1 = new Contact();
            updatedContact1 = updatedContact.first;
            await ContactsService.deleteContact(updatedContact1);
            Contact newContact = new Contact();
            newContact.givenName = myController1.text;
            newContact.emails = [
              Item(label: "email", value: myController3.text)
            ];
            newContact.company = myController2.text;
            newContact.phones = [
              Item(label: "mobile", value: myController4.text)
            ];
            newContact.postalAddresses = [
              PostalAddress(region: myController6.text)
            ];
            await ContactsService.addContact(newContact);
          } else if (widget.checkPrev == 'from_btn') {
            Contact newContact = new Contact();
            newContact.givenName = myController1.text;
            newContact.emails = [
              Item(label: "email", value: myController3.text)
            ];
            newContact.company = myController2.text;
            newContact.phones = [
              Item(label: "mobile", value: myController4.text)
            ];
            newContact.postalAddresses = [
              PostalAddress(region: myController6.text)
            ];
            await ContactsService.addContact(newContact);
          }
        }
      } else {
        if (widget.checkPrev == 'for_edit') {
          // Contact updatedContact = new Contact();
          Iterable<Contact> updatedContact =
              await ContactsService.getContacts(query: myController1.text);

          await ContactsService.deleteContact(updatedContact.first);
          // Contact updatedContact1 = new Contact();
          // updatedContact1= updatedContact.first;
          Contact newContact = new Contact();
          newContact.givenName = myController1.text;
          newContact.emails = [Item(label: "email", value: myController3.text)];
          newContact.company = myController2.text;
          newContact.phones = [
            Item(label: "mobile", value: myController4.text)
          ];
          newContact.postalAddresses = [
            PostalAddress(region: myController6.text)
          ];
          await ContactsService.addContact(newContact);
        } else if (widget.checkPrev == 'from_btn') {
          Contact newContact = new Contact();
          newContact.givenName = myController1.text;
          newContact.emails = [Item(label: "email", value: myController3.text)];
          newContact.company = myController2.text;
          newContact.phones = [
            Item(label: "mobile", value: myController4.text)
          ];
          newContact.postalAddresses = [
            PostalAddress(region: myController6.text)
          ];
          await ContactsService.addContact(newContact);
        }
      }
    } catch (e) {
      print(e);
    }
  }

这将保存联系人并在当前应用程序中进行更改时编辑联系人。

【讨论】：