firebase db

activity_main.xml

 

 

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context=".MainActivity">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content">

        <LinearLayout
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:orientation="vertical">

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="horizontal">

                <TextView
                    android:id="@+id/text_id"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="ID: "
                    android:textSize="15dp" />

                <EditText
                    android:id="@+id/edit_id"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:inputType="textPersonName" />

            </LinearLayout>

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="horizontal">

                <TextView
                    android:id="@+id/text_name"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="NAME: "
                    android:textSize="15dp" />

                <EditText
                    android:id="@+id/edit_name"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:inputType="textPersonName"
                    android:maxLength="10" />
            </LinearLayout>
        </LinearLayout>

        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="10dp"
            android:layout_gravity="bottom"
            android:orientation="vertical">

            <Button
                android:id="@+id/btn_insert"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:background="#AFEEEE"
                android:text="Insert" />
        </LinearLayout>
    </LinearLayout>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:orientation="vertical">

            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="horizontal">

                <TextView
                    android:id="@+id/text_age"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="AGE: "
                    android:textSize="15dp" />

                <EditText
                    android:id="@+id/edit_age"
                    android:layout_width="match_parent"
                    android:layout_height="wrap_content"
                    android:inputType="textPersonName"
                    android:maxLength="10" />
            </LinearLayout>
            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="horizontal">

                <TextView
                    android:id="@+id/text_gender"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="GENDER: "
                    android:textSize="15dp" />

                <CheckBox
                    android:id="@+id/check_man"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="Man"
                    android:textSize="15dp" />

                <CheckBox
                    android:id="@+id/check_woman"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:text="Woman"
                    android:textSize="15dp" />
            </LinearLayout>

        </LinearLayout>

        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="bottom"
            android:layout_marginLeft="10dp"
            android:orientation="vertical">

            <Button
                android:id="@+id/btn_update"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:background="#AFEEEE"
                android:text="Update" />

        </LinearLayout>
    </LinearLayout>

    <View
        android:id="@+id/line1"
        android:layout_width="match_parent"
        android:layout_height="2dip"
        android:layout_marginTop="2dp"
        android:layout_marginBottom="2dp"
        android:background="#AAAAAA" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal">

        <LinearLayout
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:layout_gravity="center_vertical"
            android:orientation="horizontal">

            <TextView
                android:id="@+id/text_sort"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Sort by "
                android:textSize="15sp" />

            <CheckBox
                android:id="@+id/check_age"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Age"
                android:textSize="15sp" />

            <CheckBox
                android:id="@+id/check_name"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Name"
                android:textSize="15sp" />

            <CheckBox
                android:id="@+id/check_userid"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="ID"
                android:textSize="15sp" />


        </LinearLayout>

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

            <Button
                android:id="@+id/btn_select"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_gravity="right"
                android:background="#AFEEEE"
                android:text="View" />
        </LinearLayout>
    </LinearLayout>

    <View
        android:id="@+id/line2"
        android:layout_width="match_parent"
        android:layout_height="2dip"
        android:layout_below="@+id/text_sort"
        android:layout_marginTop="2dp"
        android:layout_marginBottom="2dp"
        android:background="#AAAAAA" />

    <ScrollView
        android:id="@+id/scroll_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:fillViewport="true" >

        <ListView
            android:id="@+id/db_list_view"
            android:layout_width="match_parent"
            android:layout_height="match_parent"></ListView>

    </ScrollView>


</LinearLayout>

MainActivity.java

package com.example.firebaseex2;

import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;

import android.content.DialogInterface;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

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.Query;
import com.google.firebase.database.ValueEventListener;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;

public class MainActivity extends AppCompatActivity implements View.OnClickListener{

    private DatabaseReference mPostReference;

    Button btn_Update, btn_Insert, btn_Select;
    EditText edit_ID, edit_Name, edit_Age;
    TextView text_ID, text_Name,text_Age, text_Gender;
    CheckBox check_Man, check_Woman;
    CheckBox check_ID, check_Name,check_Age;

    String ID;
    String name;
    long age;
    String gender = "";
    String sort = "id";

    ArrayAdapter<String> arrayAdapter;

    static ArrayList<String> arrayIndex =  new ArrayList<String>();
    static ArrayList<String> arrayData = new ArrayList<String>();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        edit_ID = (EditText) findViewById(R.id.edit_id);
        edit_Name = (EditText) findViewById(R.id.edit_name);
        edit_Age = (EditText) findViewById(R.id.edit_age);
        text_ID = (TextView) findViewById(R.id.text_id);
        text_Name = (TextView) findViewById(R.id.text_name);
        text_Age = (TextView) findViewById(R.id.text_age);
        text_Gender= (TextView) findViewById(R.id.text_gender);

        btn_Insert = (Button) findViewById(R.id.btn_insert);
        btn_Insert.setOnClickListener(this);
        btn_Update = (Button) findViewById(R.id.btn_update);
        btn_Update.setOnClickListener(this);
        btn_Select = (Button) findViewById(R.id.btn_select);
        btn_Select.setOnClickListener(this);
        check_Man = (CheckBox) findViewById(R.id.check_man);
        check_Man.setOnClickListener(this);
        check_Woman = (CheckBox) findViewById(R.id.check_woman);
        check_Woman.setOnClickListener(this);
        check_ID = (CheckBox) findViewById(R.id.check_userid);
        check_ID.setOnClickListener(this);
        check_Name = (CheckBox) findViewById(R.id.check_name);
        check_Name.setOnClickListener(this);
        check_Age = (CheckBox) findViewById(R.id.check_age);
        check_Age.setOnClickListener(this);

        arrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1);
        ListView listView = (ListView) findViewById(R.id.db_list_view);
        listView.setAdapter(arrayAdapter);
        listView.setOnItemClickListener(onClickListener);
        listView.setOnItemLongClickListener(longClickListener);

        check_ID.setChecked(true);
        getFirebaseDatabase();

        btn_Insert.setEnabled(true);
        btn_Update.setEnabled(false);
    }

    public void setInsertMode(){
        edit_ID.setText("");
        edit_Name.setText("");
        edit_Age.setText("");
        check_Man.setChecked(false);
        check_Woman.setChecked(false);
        btn_Insert.setEnabled(true);
        btn_Update.setEnabled(false);
    }

    private AdapterView.OnItemClickListener onClickListener = new AdapterView.OnItemClickListener() {
        @Override
        public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            Log.e("On Click", "position = " + position);
            Log.e("On Click", "Data: " + arrayData.get(position));
            String[] tempData = arrayData.get(position).split("\\s+");
            Log.e("On Click", "Split Result = " + tempData);
            edit_ID.setText(tempData[0].trim());
            edit_Name.setText(tempData[1].trim());
            edit_Age.setText(tempData[2].trim());
            if(tempData[3].trim().equals("Man")){
                check_Man.setChecked(true);
                gender = "Man";
            }else{
                check_Woman.setChecked(true);
                gender = "Woman";
            }
            edit_ID.setEnabled(false);
            btn_Insert.setEnabled(false);
            btn_Update.setEnabled(true);
        }
    };

    private AdapterView.OnItemLongClickListener longClickListener = new AdapterView.OnItemLongClickListener() {
        @Override
        public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
            Log.d("Long Click", "position = " + position);
            final String[] nowData = arrayData.get(position).split("\\s+");
            ID = nowData[0];
            String viewData = nowData[0] + ", " + nowData[1] + ", " + nowData[2] + ", " + nowData[3];
            AlertDialog.Builder dialog = new AlertDialog.Builder(MainActivity.this);
            dialog.setTitle("데이터 삭제")
                    .setMessage("해당 데이터를 삭제 하시겠습니까?" + "\n" + viewData)
                    .setPositiveButton("네", new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialog, int which) {
                            postFirebaseDatabase(false);
                            getFirebaseDatabase();
                            setInsertMode();
                            edit_ID.setEnabled(true);
                            Toast.makeText(MainActivity.this, "데이터를 삭제했습니다.", Toast.LENGTH_SHORT).show();
                        }
                    })
                    .setNegativeButton("아니오", new DialogInterface.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialog, int which) {
                            Toast.makeText(MainActivity.this, "삭제를 취소했습니다.", Toast.LENGTH_SHORT).show();
                            setInsertMode();
                            edit_ID.setEnabled(true);
                        }
                    })
                    .create()
                    .show();
            return false;
        }
    };

    public boolean IsExistID(){
        boolean IsExist = arrayIndex.contains(ID);
        return IsExist;
    }

    public void postFirebaseDatabase(boolean add){
        mPostReference = FirebaseDatabase.getInstance().getReference();
        Map<String, Object> childUpdates = new HashMap<>();
        Map<String, Object> postValues = null;
        if(add){
            FirebasePost post = new FirebasePost(ID, name, age, gender);
            postValues = post.toMap();
        }
        childUpdates.put("/id_list/" + ID, postValues);
        mPostReference.updateChildren(childUpdates);
    }

    public void getFirebaseDatabase(){
        ValueEventListener postListener = new ValueEventListener() {
            @Override
            public void onDataChange(DataSnapshot dataSnapshot) {
                Log.e("getFirebaseDatabase", "key: " + dataSnapshot.getChildrenCount());
                arrayData.clear();
                arrayIndex.clear();
                for (DataSnapshot postSnapshot: dataSnapshot.getChildren()) {
                    String key = postSnapshot.getKey();
                    FirebasePost get = postSnapshot.getValue(FirebasePost.class);
                    String[] info = {get.id, get.name, String.valueOf(get.age), get.gender};
                    String Result = setTextLength(info[0],10) + setTextLength(info[1],10) + 
                                    setTextLength(info[2],10) + setTextLength(info[3],10);
                    arrayData.add(Result);
                    arrayIndex.add(key);
                    Log.d("getFirebaseDatabase", "key: " + key);
                    Log.d("getFirebaseDatabase", "info: " + info[0] + info[1] + info[2] + info[3]);
                }
                arrayAdapter.clear();
                arrayAdapter.addAll(arrayData);
                arrayAdapter.notifyDataSetChanged();
            }

            @Override
            public void onCancelled(DatabaseError databaseError) {
                Log.w("getFirebaseDatabase","loadPost:onCancelled", databaseError.toException());
            }
        };
        Query sortbyAge = FirebaseDatabase.getInstance().getReference().child("id_list").orderByChild(sort);
        sortbyAge.addListenerForSingleValueEvent(postListener);
    }

    public String setTextLength(String text, int length){
        if(text.length()<length){
            int gap = length - text.length();
            for (int i=0; i<gap; i++){
                text = text + " ";
            }
        }
        return text;
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.btn_insert:
                ID = edit_ID.getText().toString();
                name = edit_Name.getText().toString();
                age = Long.parseLong(edit_Age.getText().toString());
                if(!IsExistID()){
                    postFirebaseDatabase(true);
                    getFirebaseDatabase();
                    setInsertMode();
                }else{
                    Toast.makeText(MainActivity.this, "이미 존재하는 ID 입니다. 다른 ID로 설정해주세요.",
                                   Toast.LENGTH_LONG).show();
                }
                edit_ID.requestFocus();
                edit_ID.setCursorVisible(true);
                break;

            case R.id.btn_update:
                ID = edit_ID.getText().toString();
                name = edit_Name.getText().toString();
                age = Long.parseLong(edit_Age.getText().toString());
                postFirebaseDatabase(true);
                getFirebaseDatabase();
                setInsertMode();
                edit_ID.setEnabled(true);
                edit_ID.requestFocus();
                edit_ID.setCursorVisible(true);
                break;

            case R.id.btn_select:
                getFirebaseDatabase();
                break;

            case R.id.check_man:
                check_Woman.setChecked(false);
                gender = "Man";
                break;

            case R.id.check_woman:
                check_Man.setChecked(false);
                gender = "Woman";
                break;

            case R.id.check_userid:
                check_Name.setChecked(false);
                check_Age.setChecked(false);
                sort = "id";
                break;

            case R.id.check_name:
                check_ID.setChecked(false);
                check_Age.setChecked(false);
                sort = "name";
                break;

            case R.id.check_age:
                check_ID.setChecked(false);
                check_Name.setChecked(false);
                sort = "age";
                break;
        }
    }
}