package com.example.xlfbook;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<CostBean> mCostBeanList;private DatabaseHelper mdatabaseHelper;private CostListAdapter mAdapter;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);Toolbar toolbar = findViewById(R.id.toolbar);setSupportActionBar(toolbar);mdatabaseHelper=new DatabaseHelper(this);mCostBeanList=new ArrayList<>();ListView costList=(ListView)findViewById(R.id.lv_main);initCostData();mAdapter = new CostListAdapter(this, mCostBeanList);costList.setAdapter(mAdapter);FloatingActionButton fab = findViewById(R.id.fab);fab.setOnClickListener(new View.OnClickListener() {@Overridepublic 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_cost_data,null);final EditText title=(EditText) viewDialog.findViewById(R.id.et_cost_title);final EditText money=(EditText)viewDialog.findViewById(R.id.et_cost_money);final DatePicker date=(DatePicker) viewDialog.findViewById(R.id.dp_cost_data);builder.setView(viewDialog);builder.setTitle("New Cost");builder.setPositiveButton("OK", new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {CostBean costBean=new CostBean();costBean.costTitle=title.getText().toString();costBean.costMoney=money.getText().toString();costBean.costDate=date.getYear()+"-"+(date.getMonth()+1)+"-"+date.getDayOfMonth();mdatabaseHelper.insertCost(costBean);mCostBeanList.add(costBean);mAdapter.notifyDataSetChanged();}});builder.setNegativeButton("Cancel",null);//点击取消builder.create().show();//显示dialog的布局
            }});}private void initCostData() {// mdatabaseHelper.deleteAllData();/* CostBean costBean=new CostBean();for (int i=0;i<6;i++) {costBean.costTitle=i+"imooc";costBean.costDate="11-11";costBean.costMoney="20";mdatabaseHelper.insertCost(costBean);}*/Cursor cursor=mdatabaseHelper.getAllCostData();if(cursor!=null){while(cursor.moveToNext()){CostBean costBean1=new CostBean();costBean1.costTitle=cursor.getString(cursor.getColumnIndex("cost_title"));costBean1.costDate=cursor.getString(cursor.getColumnIndex("cost_date"));costBean1.costMoney=cursor.getString(cursor.getColumnIndex("cost_money"));mCostBeanList.add(costBean1);}cursor.close();}}@Overridepublic 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;}@Overridepublic 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 SimplifiableIfStatementif (id == R.id.action_chart) {Intent intent=new Intent(MainActivity.this,ChartsActivity.class);intent.putExtra("cost_list", (Serializable) mCostBeanList);startActivity(intent);return true;}return super.onOptionsItemSelected(item);}
}

接下来简单的添加一笔帐单的功能已经可以实现，我们来添加一笔账单试试效果。

（二）开始制作图表

图表的制作我们会用到第三方库hellocharts，具体可以登录该网址查看————https://github.com/lecho/hellocharts-android

接下来在Android Studio中导入该库，在build中的dependencies中导入该github就可以了

接下来首先创建一个布局文件，来展示我们的chart图表。

chart_view

<?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:padding="10dp"><lecho.lib.hellocharts.view.LineChartViewandroid:id="@+id/chart"android:padding="20dp"android:layout_width="match_parent"android:layout_height="match_parent" /></LinearLayout>

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 SimplifiableIfStatementif (id == R.id.action_chart) {Intent intent=new Intent(MainActivity.this,ChartsActivity.class);intent.putExtra("cost_list", (Serializable) mCostBeanList);startActivity(intent);return true;}return super.onOptionsItemSelected(item);}

<menu 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"tools:context="com.example.xlfbook.MainActivity"><itemandroid:id="@+id/action_chart"android:orderInCategory="100"android:title="Charts"app:showAsAction="never" />
</menu>

package com.example.xlfbook;import android.app.Activity;
import android.content.Intent;
import android.graphics.Color;
import android.os.Bundle;import androidx.annotation.Nullable;import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.TreeMap;import lecho.lib.hellocharts.model.Axis;
import lecho.lib.hellocharts.model.AxisValue;
import lecho.lib.hellocharts.model.ChartData;
import lecho.lib.hellocharts.model.Line;
import lecho.lib.hellocharts.model.LineChartData;
import lecho.lib.hellocharts.model.PointValue;
import lecho.lib.hellocharts.model.ValueShape;
import lecho.lib.hellocharts.util.ChartUtils;
import lecho.lib.hellocharts.view.Chart;
import lecho.lib.hellocharts.view.LineChartView;public class ChartsActivity extends Activity {private LineChartView mChart;private Map<String,Integer> table = new TreeMap<>();private LineChartData mData;@Overrideprotected void onCreate(@Nullable Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.chart_view);mChart = (LineChartView) findViewById(R.id.chart);mData = new LineChartData();List<CostBean> allDate = (List<CostBean>) getIntent().getSerializableExtra("cost_list");generateValues(allDate);generateData();}private void generateData() {List<Line> lines = new ArrayList<>();List<PointValue> values = new ArrayList<>();int indexX = 0;for(Integer value : table.values()){values.add(new PointValue(indexX, value));indexX++;}Line line = new Line(values);line.setColor(ChartUtils.COLORS[0]);line.setShape(ValueShape.CIRCLE);line.setPointColor(ChartUtils.COLORS[1]);lines.add(line);mData.setLines(lines);mChart.setLineChartData(mData);}private void generateValues(List<CostBean> allDate) {if(allDate != null){for (int i = 0; i < allDate.size(); i++) {CostBean costBean = allDate.get(i);String costDate = costBean.costDate;int costMoney = Integer.parseInt(costBean.costMoney);if(!table.containsKey(costDate)){table.put(costDate,costMoney);}else {int originMoney = table.get(costDate);table.put(costDate,originMoney + costMoney);}}}}
}