安卓学习记录（四）——体温表APP

1.新建project

file->new->new project，选择Basic Activity

2.在content_main.xml中添加一个List View

<ListView
        android:id="@+id/lv_main"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

3.绘制一个页面来展示数据（list_item.xml）

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="80dp"
    android:orientation="vertical">

    <TextView
        android:id="@+id/tv_name"
        android:layout_width="150dp"
        android:layout_height="80dp"
        android:layout_marginLeft="10dp"
        android:layout_alignParentLeft="true"
        android:gravity="center"
        android:singleLine="true"
        android:textSize="35sp"
        android:text="姓名"
        android:ellipsize="marquee" />

    <TextView
        android:id="@+id/tv_date"
        android:layout_width="wrap_content"
        android:layout_height="80dp"
        android:layout_toRightOf="@+id/tv_name"
        android:layout_marginLeft="15dp"
        android:textSize="20sp"
        android:gravity="center"
        android:text="日期"/>

    <TextView
        android:id="@+id/tv_bodyTem"
        android:layout_width="wrap_content"
        android:layout_height="80dp"
        android:text="体温"
        android:textSize="30sp"
        android:layout_marginRight="20dp"
        android:layout_alignParentRight="true"
        android:gravity="center"/>


</RelativeLayout>

4.Bean存储

package com.example.tem;

import java.io.Serializable;

public class TemBean implements Serializable{

    public String name;
    public String date;
    public String bodyTem;

    @Override
    public String toString() {
        return "TemBean{" +
                "name='" + name + '\'' +
                ", date='" + date + '\'' +
                ", bodyTem='" + bodyTem + '\'' +
                '}';
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getDate() {
        return date;
    }

    public void setDate(String date) {
        this.date = date;
    }

    public String getBodyTem() {
        return bodyTem;
    }

    public void setBodyTem(String bodyTem) {
        this.bodyTem = bodyTem;
    }

}

5.编写适配器（什么是适配器“https://blog.csdn.net/geekmubai/article/details/89297238”）

package com.example.tem;

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

import java.util.List;

public class TemListAdapter extends BaseAdapter{
    private List<TemBean> mlist;
    private Context mContext;
    private LayoutInflater mlayoutInflater;
    public TemListAdapter(Context context, List<TemBean> list){
        mContext=context;
        mlist=list;
        mlayoutInflater=LayoutInflater.from(context);
    }
    @Override
    public int getCount() {
        return mlist.size();
    }

    @Override
    public Object getItem(int position) {
        return mlist.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder viewHolder;
        if(convertView==null)
        {
            viewHolder=new ViewHolder();
            convertView=mlayoutInflater.inflate(R.layout.list_item,null);
            viewHolder.mTvName=convertView.findViewById(R.id.tv_name);
            viewHolder.mTvDate=convertView.findViewById(R.id.tv_date);
            viewHolder.mTvBodyTem=convertView.findViewById(R.id.tv_bodyTem);
            convertView.setTag(viewHolder);
        }else{
            viewHolder=(ViewHolder) convertView.getTag();
        }
        TemBean bean=mlist.get(position);
        viewHolder.mTvName.setText(bean.name);
        viewHolder.mTvDate.setText(bean.date);
        viewHolder.mTvBodyTem.setText(bean.bodyTem);
        return convertView;
    }

    private static class ViewHolder{
        public TextView mTvName;
        public TextView mTvDate;
        public TextView mTvBodyTem;
    }
}

6.建立数据库

package com.example.tem;

import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

import androidx.annotation.Nullable;

public class DatabaseHelper extends SQLiteOpenHelper {
    public static final String NAME = "name";
    public static final String DATE = "date";
    public static final String BODYTEM = "bodytem";
    public static final String TemPost = "tempost";//数据表名

    public DatabaseHelper(@Nullable Context context) {
        super(context, "temperature", null, 1);//数据库名
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
        db.execSQL("create table if not exists TemPost("+
                "id integer primary key, "+
                "name varchar, "+
                "date varchar, "+
                "bodytem varchar)");
    }
    public void insertTem(TemBean TemBean){//增
        SQLiteDatabase database=getWritableDatabase();
        ContentValues cv=new ContentValues();
        cv.put(NAME,TemBean.name);
        cv.put(DATE,TemBean.date);
        cv.put(BODYTEM,TemBean.bodyTem);
        database.insert(TemPost,null,cv);
    }
    public Cursor getAllTemData(){//查
        SQLiteDatabase database=getWritableDatabase();
        return database.query("TemPost",null,null,null,null,null,"DATE"+" ASC");
    }
    public void deleteAllData(){//删
        SQLiteDatabase database=getWritableDatabase();
        database.delete("TemPost",null,null);
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    }

}

7.使用fab图标的click弹出填写界面，先做界面（new_tem_data.xml）

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

    <EditText
        android:id="@+id/et_tem_name"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="4dp"
        android:hint="姓名"/>

    <EditText
        android:id="@+id/et_tem_bodytem"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="4dp"
        android:hint="体温"/>
    <DatePicker
        android:id="@+id/dp_tem_date"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_margin="4dp"
        android:datePickerMode="spinner"
        android:calendarViewShown="false"/>

</LinearLayout>

8.更改MainActivity中的onClick方法

package com.example.tem;

import android.content.DialogInterface;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;

import com.google.android.material.floatingactionbutton.FloatingActionButton;
import com.google.android.material.snackbar.Snackbar;

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

import android.os.Parcelable;
import android.view.LayoutInflater;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.DatePicker;
import android.widget.EditText;
import android.widget.ListView;

import java.io.Serializable;
import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {
    private List<TemBean> mTemBeanList;
    private DatabaseHelper mdatabaseHelper;
    private TemListAdapter mAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);


        mdatabaseHelper=new DatabaseHelper(this);
        mTemBeanList=new ArrayList<>();
        ListView temList=(ListView)findViewById(R.id.lv_main);
        initTemData();
        mAdapter = new TemListAdapter(this,mTemBeanList);
        temList.setAdapter(mAdapter);

        FloatingActionButton fab = findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                AlertDialog.Builder builder=new AlertDialog.Builder(MainActivity.this);
                LayoutInflater inflater=LayoutInflater.from(MainActivity.this);
                View viewDialog=inflater.inflate(R.layout.new_tem_data,null);
                final EditText name=(EditText) viewDialog.findViewById(R.id.et_tem_name);
                final EditText bodytem=(EditText)viewDialog.findViewById(R.id.et_tem_bodytem);
                final DatePicker date=(DatePicker) viewDialog.findViewById(R.id.dp_tem_date);
                builder.setView(viewDialog);
                builder.setTitle("填写体温");
                builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        TemBean temBean=new TemBean();
                        temBean.name=name.getText().toString();
                        temBean.bodyTem=bodytem.getText().toString();
                        temBean.date=date.getYear()+"-"+(date.getMonth()+1)+"-"+date.getDayOfMonth();
                        mdatabaseHelper.insertTem(temBean);
                        mTemBeanList.add(temBean);
                        mAdapter.notifyDataSetChanged();
                    }
                });
                builder.setNegativeButton("Cancel",null);//点击取消
                builder.create().show();//显示dialog的布局
            }
        });
    }

    private void initTemData() {
        Cursor cursor=mdatabaseHelper.getAllTemData();
        if(cursor!=null){
            while(cursor.moveToNext()){
                TemBean temBean1=new TemBean();
                temBean1.name=cursor.getString(cursor.getColumnIndex("name"));
                temBean1.date=cursor.getString(cursor.getColumnIndex("date"));
                temBean1.bodyTem=cursor.getString(cursor.getColumnIndex("bodytem"));
                mTemBeanList.add(temBean1);
            }
            cursor.close();
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }
}

完成

效果图：