book/UserActivity.java

package com.grassroots.booktracker.activity;

import android.content.ContentValues;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.text.TextUtils;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import com.grassroots.booktracker.R;
import com.grassroots.booktracker.adapter.BookInfo;
import com.grassroots.booktracker.adapter.BookInfoAdapter;
import com.grassroots.booktracker.utils.DatabaseHelper;

import java.util.ArrayList;
import java.util.List;

public class UserActivity extends AppCompatActivity {
    private Button insertButton, updateButton, searchButton, deleteButton;
    private EditText name, day;

    private RecyclerView rvBookInfo;

    private TextView tvCount ,tvDays;

    private BookInfoAdapter bookInfoAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_user);
        TextView tvTitle = findViewById(R.id.tv_main_title);
        tvTitle.setText("借阅信息");
        TextView tvBack = findViewById(R.id.tv_back);
        tvBack.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                finish();
            }
        });
        TextView tvUsername = findViewById(R.id.tv_username);
        String loginUserName = getSharedPreferences("loginInfo", MODE_PRIVATE).getString("loginUserName", "");
        tvUsername.setText(loginUserName);

        rvBookInfo = findViewById(R.id.rv_book_info);
        insertButton = findViewById(R.id.btn_insert);
        updateButton = findViewById(R.id.btn_update);
        searchButton = findViewById(R.id.btn_search);
        deleteButton = findViewById(R.id.btn_delete);
        name = findViewById(R.id.name);
        day = findViewById(R.id.day);
        tvCount = findViewById(R.id.tv_count);
        tvDays = findViewById(R.id.tv_days);

        tvCount.setText("共借阅"+getCount()+"本");
        tvDays.setText("共借阅"+getAllDays()+"天");

        initRv();

        SQLiteDatabase db = DatabaseHelper.getInstance().getReadableDatabase();

        myShow();


        insertButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (TextUtils.isEmpty(name.getText().toString())){
                    Toast.makeText(UserActivity.this, "请输入书名", Toast.LENGTH_SHORT).show();
                    return;
                }
                if (TextUtils.isEmpty(day.getText().toString())){
                    Toast.makeText(UserActivity.this, "请输入借阅天数", Toast.LENGTH_SHORT).show();
                    return;
                }
                SQLiteDatabase db = DatabaseHelper.getInstance().getWritableDatabase();
                ContentValues values = new ContentValues();
                values.put("name", name.getText().toString());
                values.put("days", day.getText().toString());
                long id = db.insert("information", null, values);
                Log.d("myDeBug", "insert");

                myShow();


                db.close();
                name.setText(null);
                day.setText(null);

                tvCount.setText("共借阅"+getCount()+"本");
                tvDays.setText("共借阅"+getAllDays()+"天");
            }
        });
        updateButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                if (TextUtils.isEmpty(name.getText().toString())){
                    Toast.makeText(UserActivity.this, "请输入书名", Toast.LENGTH_SHORT).show();
                    return;
                }
                if (TextUtils.isEmpty(day.getText().toString())){
                    Toast.makeText(UserActivity.this, "请输入借阅天数", Toast.LENGTH_SHORT).show();
                    return;
                }
                SQLiteDatabase db = DatabaseHelper.getInstance().getWritableDatabase();
                ContentValues values = new ContentValues();
                values.put("days", day.getText().toString());
                db.update("information", values, "name=?", new String[]{name.getText().toString()});

                myShow();


                db.close();
                Log.d("myDebug", "update");
                name.setText(null);
                day.setText(null);

                tvCount.setText("共借阅"+getCount()+"本");
                tvDays.setText("共借阅"+getAllDays()+"天");
            }
        });
        searchButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                if (TextUtils.isEmpty(name.getText().toString())){
                    Toast.makeText(UserActivity.this, "请输入书名", Toast.LENGTH_SHORT).show();
                    return;
                }
                SQLiteDatabase db = DatabaseHelper.getInstance().getWritableDatabase();
                String name1 = name.getText().toString();
                if (name1.equals("")) {
                    myShow();
                    db.close();
                } else {
                    Cursor cursor = db.rawQuery("select * from information where name = ? ", new String[]{name1});

                    List<BookInfo> bookInfoList=new ArrayList<>();
                    while (cursor.moveToNext()) {
                        String newName = cursor.getString(1);
                        int newDays = cursor.getInt(2);
                        bookInfoList.add(new BookInfo(newName,newDays));
                    }
                    bookInfoAdapter.setBookInfoList(bookInfoList);

                    cursor.close();
                    db.close();
                    name.setText(null);
                    day.setText(null);
                }
            }
        });
        deleteButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                if (TextUtils.isEmpty(name.getText().toString())){
                    Toast.makeText(UserActivity.this, "请输入书名", Toast.LENGTH_SHORT).show();
                    return;
                }
                SQLiteDatabase db = DatabaseHelper.getInstance().getWritableDatabase();
                db.delete("information", "name=?", new String[]{name.getText().toString()});


                myShow();


                db.close();
                Log.d("myDeBug", "DeleteSuccess");
                name.setText(null);
                day.setText(null);

                tvCount.setText("共借阅"+getCount()+"本");
                tvDays.setText("共借阅"+getAllDays()+"天");
            }
        });

    }

    private int getCount(){
        SQLiteDatabase db = DatabaseHelper.getInstance().getReadableDatabase();
        Cursor cursor = db.rawQuery("select count(*) from information", null);
        cursor.moveToFirst();
        int count = cursor.getInt(0);
        cursor.close();
        return count;
    }

    private int getAllDays(){
        SQLiteDatabase db = DatabaseHelper.getInstance().getReadableDatabase();
        Cursor cursor = db.rawQuery("select sum(days) from information", null);
        cursor.moveToFirst();
        int count = cursor.getInt(0);
        cursor.close();
        return count;
    }

    private void initRv(){
        bookInfoAdapter = new BookInfoAdapter();
        rvBookInfo.setAdapter(bookInfoAdapter);
        rvBookInfo.setLayoutManager(new LinearLayoutManager(this));
    }

    public void myShow() {
        SQLiteDatabase db = DatabaseHelper.getInstance().getReadableDatabase();
        Cursor cursor = db.rawQuery("select * from information", null);
        List<BookInfo> bookInfoList=new ArrayList<>();
        while (cursor.moveToNext()) {
            String newName = cursor.getString(1);
            int newDays = cursor.getInt(2);
            bookInfoList.add(new BookInfo(newName,newDays));
        }
        cursor.close();
        bookInfoAdapter.setBookInfoList(bookInfoList);
    }
}