4-1打卡

今天开始规划了小队作业增删改查
• 所花时间：5
• 代码行数：289
• 博客容量：1
• 代码如下：

package com.example.dbpractice;

import androidx.appcompat.app.AppCompatActivity;

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

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

public class DictActivity extends AppCompatActivity {
    private Button insertButton,updateButton,searchButton,deleteButton;
    private EditText name,age;
    private TextView show,showAge;
    final DatabaseHelper dbHelper=new DatabaseHelper(DictActivity.this);
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_dict);

        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);
        age=findViewById(R.id.age);
        show=findViewById(R.id.tv_show);
        showAge=findViewById(R.id.tv_showAge);



        SQLiteDatabase db=dbHelper.getReadableDatabase();

        myShow();


        insertButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                SQLiteDatabase db=dbHelper.getWritableDatabase();
                ContentValues values=new ContentValues();
                values.put("name",name.getText().toString());
                values.put("age",age.getText().toString());
                long id =db.insert("information",null,values);
                Log.d("myDeBug","insert");

                myShow();


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

                SQLiteDatabase db=dbHelper.getWritableDatabase();
                ContentValues values=new ContentValues();
                values.put("age",age.getText().toString());
                db.update("information",values,"name=?",new String[]{name.getText().toString()});

                myShow();


                db.close();
                Log.d("myDebug","update");
                name.setText(null);
                age.setText(null);
            }
        });
        searchButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                SQLiteDatabase db=dbHelper.getWritableDatabase();
                String name1=name.getText().toString();
                show.setText(null);
                if(name1.equals("")){
//                    show.setText("姓名");
//                    showAge.setText("年龄");
//                    Cursor cursor = db.rawQuery("select * from information",null);
//
//                    while (cursor.moveToNext()) {
//                        String newName = cursor.getString(cursor.getColumnIndex("name"));
//                        int newAge = cursor.getInt(cursor.getColumnIndex("age"));
//                        show.setText(show.getText() + "\n" + newName);
//                        showAge.setText(showAge.getText()+"\n" + newAge);
//                    }

                    myShow();

                    db.close();
                }else {
                    show.setText("姓名");
                    showAge.setText("年龄");
                    Cursor cursor = db.rawQuery("select * from information where name = ? ", new String[]{name1});

                    while (cursor.moveToNext()) {
                        String newName = cursor.getString(cursor.getColumnIndex("name"));
                        int newAge = cursor.getInt(cursor.getColumnIndex("age"));
//                        show.setText(show.getText() + "\n" + newName + "\t" + newAge);
                        show.setText(show.getText() + "\n" + newName);
                        showAge.setText(showAge.getText()+"\n" + newAge);
                    }

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

                SQLiteDatabase db=dbHelper.getWritableDatabase();
                db.delete("information","name=?",new String[]{name.getText().toString()});


                myShow();


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

    }

    public void myShow(){
        SQLiteDatabase db=dbHelper.getReadableDatabase();


        show.setText("姓名");
        showAge.setText("年龄");
        Cursor cursor = db.rawQuery("select * from information",null);

        while (cursor.moveToNext()) {
            String newName = cursor.getString(cursor.getColumnIndex("name"));
            int newAge = cursor.getInt(cursor.getColumnIndex("age"));
            show.setText(show.getText() + "\n" + newName);
            showAge.setText(showAge.getText()+"\n" + newAge);
        }
        cursor.close();
    }
}