안드로이드 - QR코드 스캔하여 Firebase Realtime Database에 저장하기 (QR스캐너)

프로젝트 중 QR코드를 스캔하는 기능이 필요해 구글링 해보던 중 QR 코드 스캔을 할 수 있는 라이브러리가 있다는 것 을 알고 블로그를 참고 하였다.

 

firebase의 데이터베이스와 연동하는 것은 지난 글에 있으므로 생략했다.

 

 

 

프로젝트 생성 후 앱을 빌드한 후 firebase와 연동하여 데이터베이스를 쓸 것이다.

 

 

 

QR코드를 찍어서 txt 데이터를 json 형태로 받은 후에 그것을 firebase database에 저장 할 것이다.

 

QR코드 만드는 사이트는 다음과 같다. text형태로 만들었다.

 

goqr.me

QR Code Generator – create QR codes for free (Logo, T-Shirt, vCard, EPS)

 

구현 영상.

 

 

필요한 정보 학과, 학번, 이름의 데이터가 담긴 큐알코드를 만들고, 그것을 이용하여 찍으면 EditText에 데이터가 담기는데 그것을 버튼을 통하여 데이터베이스에 저장되게 된다.

 

 

큐알의 text는 다음과 같은 형태로 입력하였다. 

 

{"userNumber":"21261239","userPassword":"정보통신공학과","userName":"홍길동"}

 

 

<MainActivity.java>

package com.example.qrscan;

import android.app.Activity;
import android.content.Intent;

import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import android.widget.Toast;

import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;

import com.google.android.gms.tasks.OnFailureListener;
import com.google.android.gms.tasks.OnSuccessListener;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.ValueEventListener;
import com.google.zxing.integration.android.IntentIntegrator;
import com.google.zxing.integration.android.IntentResult;

import org.json.JSONException;
import org.json.JSONObject;

import java.util.HashMap;

import static java.security.AccessController.getContext;

public class MainActivity extends AppCompatActivity {
    //view Objects
    private Button buttonScan,btn_save;
    private TextView textViewName, textViewAddress, textViewResult;
    int a = 0;

    //qr code scanner object
    private IntentIntegrator qrScan;
    private DatabaseReference mDatabase;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);


        btn_save = findViewById(R.id.button);


        mDatabase = FirebaseDatabase.getInstance().getReference();

        readUser();

        btn_save.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String getUserName = textViewName.getText().toString();
                String getUserPassword = textViewAddress.getText().toString();
                String getUserNumber = textViewResult.getText().toString();

                //hashmap 만들기
                HashMap result = new HashMap<>();
                result.put("학과", getUserPassword);
                result.put("학번", getUserNumber);
                result.put("이름",getUserName);

                a = a+1;
                writeNewUser(a,getUserPassword,getUserNumber,getUserName);

            }
        });

        //View Objects
        buttonScan = (Button) findViewById(R.id.buttonScan);
        textViewName = (TextView) findViewById(R.id.textViewName);
        textViewAddress = (TextView) findViewById(R.id.textViewPassword);
        textViewResult = (TextView)  findViewById(R.id.textViewResult);

        //intializing scan object
        qrScan = new IntentIntegrator(this);

        //button onClick
        buttonScan.setOnClickListener(new View.OnClickListener() {
            public void onClick(View v) {
                //scan option
                qrScan.setPrompt("Scanning...");
                //qrScan.setOrientationLocked(false);
                qrScan.initiateScan();
            }
        });
    }

    //Getting the scan results
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data){
        IntentResult result = IntentIntegrator.parseActivityResult(requestCode, resultCode, data);
        if (result != null) {
            //qrcode 가 없으면
            if (result.getContents() == null) {
                Toast.makeText(MainActivity.this, "취소!", Toast.LENGTH_SHORT).show();
            } else {
                //qrcode 결과가 있으면
                Toast.makeText(MainActivity.this, "스캔완료!", Toast.LENGTH_SHORT).show();
                try {
                    //data를 json으로 변환
                    JSONObject obj = new JSONObject(result.getContents());
                    textViewAddress.setText(obj.getString("userPassword"));
                    textViewName.setText(obj.getString("userNumber"));
                    textViewResult.setText(obj.getString("userName"));
                } catch (JSONException e) {
                    e.printStackTrace();
                    //Toast.makeText(MainActivity.this, result.getContents(), Toast.LENGTH_LONG).show();
                    textViewResult.setText(result.getContents());
                }
            }

        } else {
            super.onActivityResult(requestCode, resultCode, data);
        }
    }

    private void writeNewUser(int userId, String userName, String userPassword, String userNumber) {
        user user = new user(userName, userPassword, userNumber);

        mDatabase.child("users").child(String.valueOf(userId)).setValue(user)
                .addOnSuccessListener(new OnSuccessListener<Void>() {
                    @Override
                    public void onSuccess(Void aVoid) {
                        // Write was successful!
                        Toast.makeText(MainActivity.this, "저장을 완료했습니다.", Toast.LENGTH_SHORT).show();
                    }
                })
                .addOnFailureListener(new OnFailureListener() {
                    @Override
                    public void onFailure(@NonNull Exception e) {
                        // Write failed
                        Toast.makeText(MainActivity.this, "저장을 실패했습니다.", Toast.LENGTH_SHORT).show();
                    }
                });

    }

    private void readUser(){
        mDatabase.child("users").child("1").addValueEventListener(new ValueEventListener() {
            @Override
            public void onDataChange(@NonNull DataSnapshot dataSnapshot) {
                // Get Post object and use the values to update the UI
                if(dataSnapshot.getValue(user.class) != null){
                    user post = dataSnapshot.getValue(user.class);
                    Log.w("FireBaseData", "getData" + post.toString());
                } else {
                    Toast.makeText(MainActivity.this, "데이터 없음...", Toast.LENGTH_SHORT).show();
                }
            }

            @Override
            public void onCancelled(@NonNull DatabaseError databaseError) {
                // Getting Post failed, log a message
                Log.w("FireBaseData", "loadPost:onCancelled", databaseError.toException());
            }
        });
    }








}

 

 

class 추가

 

 

<user.java>

package com.example.qrscan;

public class user {

    public String userName;
    public String userNumber;
    public String userPassword;

    public user() {
        // Default constructor required for calls to DataSnapshot.getValue(User.class)
    }

    public user(String userName, String userNumber, String userPassword) {
        this.userName = userName;
        this.userNumber = userNumber;
        this.userPassword = userPassword;
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getUserNumber() {
        return userNumber;
    }

    public void setUserNumber(String userNumber) {
        this.userNumber = userNumber;
    }
    public String getUserPassword() {
        return userPassword;
    }

    public void setUserPassword(String userPassword) {
        this.userPassword = userPassword;
    }

    @Override
    public String toString() {
        return "user{" +
                "userPassword ='" + userPassword + '\'' +
                ", userNumber ='" + userNumber + '\'' +
                ", userName ='" + userName + '\'' +
                '}';
    }
}

 

 

<activity_main.xml>

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="10dp"
    android:paddingLeft="10dp"
    android:paddingRight="50dp"
    android:paddingTop="50dp"
    tools:context="MainActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_centerVertical="true"
        android:orientation="vertical">



        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="학번" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text=""
            android:id="@+id/textViewName"
            android:textAppearance="@style/Base.TextAppearance.AppCompat.Large" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="학과" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text=""
            android:id="@+id/textViewPassword"
            android:textAppearance="@style/Base.TextAppearance.AppCompat.Large" />

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="이름" />

        <EditText
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text=""
            android:id="@+id/textViewResult"
            android:textAppearance="@style/Base.TextAppearance.AppCompat.Large" />

    </LinearLayout>

    <Button
        android:text="SCAN QR CODE"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_centerHorizontal="true"
        android:layout_marginBottom="12dp"
        android:id="@+id/buttonScan" />

    <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_marginTop="10dp"
        android:layout_marginBottom="163dp"
        android:text="저장하기" />


</RelativeLayout>

 

 

 

 

참고 글 :  (QR 스캔) m.blog.naver.com/cosmosjs/220937443111