个人博客

1.学到的东西

package com.example.jiwtingjizhangben;

import androidx.appcompat.app.AppCompatActivity;
import androidx.lifecycle.ViewModelProvider;

import android.content.Intent;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.widget.ListView;
import android.widget.TextView;

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

public class MainActivity extends AppCompatActivity {
    DatabaseHelper helper = null;
    SQLiteDatabase db = null;
    String sql = null;

    Double ZongZhichu = 0.0;
    Double ZongShouru = 0.0;

    ArrayList<Info> list = null;

    TextView tvTotal = null;

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

        ListView listView = findViewById(R.id.listview);
        List<Info> list = getData();
        listView.setAdapter(new MyAdapter(this, list));

        tvTotal = findViewById(R.id.tv_total);
        tvTotal.setText("总收入：" + ZongShouru + "\n总支出：" + ZongZhichu);

    }

    public List<Info> getData() {
        list = new ArrayList<>();

        helper = new DatabaseHelper(this, "demo.db", null, 1);
        db = helper.getReadableDatabase();

        sql = "select * from infos";
        Cursor cursor = db.rawQuery(sql, null);
        System.out.println(cursor);

        while (cursor.moveToNext()) {
            Info info = new Info();
            String number = cursor.getString(0);
            String name = cursor.getString(1);
            String date = cursor.getString(2);

            info.setNumber(number);
            info.setName(name);
            info.setDate(date);

            if (Double.parseDouble(number) < 0) {
                ZongZhichu -= Double.parseDouble(number);
            } else {
                ZongShouru += Double.parseDouble(number);
            }
            list.add(info);
        }
        return list;
    }

    public void shuaxin(View view){
        ListView listView = findViewById(R.id.listview);
        List<Info> list = getData();
        listView.setAdapter(new MyAdapter(this, list));

    }

    public void shouru(View view){
        Intent intent = new Intent(this,shouruActivity.class);
        this.startActivity(intent);
    }

    public void zhichu(View view){
        Intent intent = new Intent(this,zhichuActivity.class);
        this.startActivity(intent);
    }
}

package com.example.jiwtingjizhangben;

import androidx.appcompat.app.AppCompatActivity;

import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

import java.text.SimpleDateFormat;
import java.util.Date;

public class shouruActivity extends AppCompatActivity {
    DatabaseHelper helper = null;
    SQLiteDatabase db = null;
    String sql = null;
    EditText et_zhichu = null;
    EditText et_name = null;
    TextView tv_date = null;
    Button btnSubmit = null;

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

        timeUpdate();

        helper = new DatabaseHelper(this, "demo.db", null, 1);
        db = helper.getWritableDatabase();

        et_zhichu = (EditText) findViewById(R.id.et_shouru);
        et_name = (EditText) findViewById(R.id.et_name);
    }

    public void timeUpdate(){
        tv_date = (TextView)findViewById(R.id.tv_date);
        SimpleDateFormat simpleDateFormatDate = new SimpleDateFormat("yyyy年MM月dd日");
        Date date = new Date(System.currentTimeMillis());
        tv_date.setText(simpleDateFormatDate.format(date));
    }

    public void submitClick(View view){
        timeUpdate();
        String number = et_zhichu.getText().toString();
        String name = et_name.getText().toString();
        String date = tv_date.getText().toString();
        sql = "insert into infos values('"+ number +"','"+name+"','"+date+"');";
        db.execSQL(sql);
    }
}

package com.example.jiwtingjizhangben;

import androidx.appcompat.app.AppCompatActivity;

import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;

import java.text.SimpleDateFormat;
import java.util.Date;

public class zhichuActivity extends AppCompatActivity {
    DatabaseHelper helper = null;
    SQLiteDatabase db = null;
    String sql = null;
    EditText et_zhichu = null;
    EditText et_name = null;
    TextView tv_date = null;
    Button btnSubmit = null;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_zhichu);

        timeUpdate();

        helper = new DatabaseHelper(this, "demo.db", null, 1);
        db = helper.getWritableDatabase();

        et_zhichu = (EditText) findViewById(R.id.et_shouru);
        et_name = (EditText) findViewById(R.id.et_name);
    }

    public void timeUpdate(){
        tv_date = (TextView)findViewById(R.id.tv_date);
        SimpleDateFormat simpleDateFormatDate = new SimpleDateFormat("yyyy年MM月dd日");
        Date date = new Date(System.currentTimeMillis());
        tv_date.setText(simpleDateFormatDate.format(date));
    }

    public void submitClick(View view){
        timeUpdate();
        String number = '-' + et_zhichu.getText().toString();
        String name = et_name.getText().toString();
        String date = tv_date.getText().toString();
        sql = "insert into infos values('"+ number +"','"+name+"','"+date+"');";
        db.execSQL(sql);
    }
}

<?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"
    tools:context=".MainActivity"
    android:orientation="vertical">

    <TextView
        android:id="@+id/tv_total"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        >
    </TextView>

    <ListView
        android:id="@+id/listview"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="8"
        >
    </ListView>

    <Button
        android:id="@+id/btn_shuaxin"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="刷新"
        android:onClick="shuaxin"
        android:layout_gravity="center"
        />
    <Button
        android:id="@+id/btn_shouru"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="收入"
        android:onClick="shouru"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        />

    <Button
        android:id="@+id/btn_zhichu"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="支出"
        android:onClick="zhichu"
        android:layout_marginTop="20dp"
        android:layout_gravity="center"
        />

</LinearLayout>

<?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"
    tools:context=".shouruActivity"
    android:orientation="vertical">

    <EditText
        android:id="@+id/et_name"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:layout_marginTop="10dp"
        android:hint="成员姓名"
        android:maxLength="12"
        android:padding="5dp"
        android:textSize="16sp" />

    <EditText
        android:id="@+id/et_shouru"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:layout_marginTop="10dp"
        android:hint="收入金额"
        android:maxLength="12"
        android:padding="5dp"
        android:textSize="16sp" />



    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="20dp"
        android:orientation="horizontal">

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:ellipsize="end"
            android:maxEms="20"
            android:text="日期："
            android:textSize="16sp" />

        <TextView
            android:id="@+id/tv_date"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:ellipsize="end"
            android:maxEms="20"
            android:text=""
            android:textSize="16sp" />
    </LinearLayout>



    <Button
        android:id="@+id/btn_submit"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_marginTop="20dp"
        android:onClick="submitClick"
        android:text="提交" />



</LinearLayout>

2.明日计划

继续完成第二阶段

3.遇到的问题