体温上报APP——柱状图 - 戈瑾

要求：

要求每人录入15天的体温数据，以折线图或柱状图展示个人15天的体温变化情况。

我采用的是MPAndroidChart。

一、过程

1、首先将MPAndroidChart的jar包导入工程中

2、绘制xml布局代码

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     android:orientation="vertical"
 4     android:layout_width="match_parent"
 5     android:layout_height="match_parent"
 6     android:background="@mipmap/bj3">
 7 
 8     <com.github.mikephil.charting.charts.BarChart
 9         android:id="@+id/show_chart"
10         android:layout_width="match_parent"
11         android:layout_height="500dp"
12         >
13 
14     </com.github.mikephil.charting.charts.BarChart>
15 </LinearLayout>

3、编写java代码

思路：

设置外观

 1 private void setLegend() {
 2         Legend legend = barChart.getLegend();
 3         legend.setFormSize(12f); 
 4         legend.setTextSize(15f); 
 5         legend.setOrientation(Legend.LegendOrientation.HORIZONTAL); 
 6         legend.setHorizontalAlignment(Legend.LegendHorizontalAlignment.LEFT); 
 7         legend.setVerticalAlignment(Legend.LegendVerticalAlignment.BOTTOM); 
 8         legend.setYOffset(55f);
 9         legend.setXOffset(30f);
10     }

设置坐标轴

private void setAxis() {
        // 设置x轴
        XAxis xAxis = barChart.getXAxis();
        xAxis.setPosition(XAxis.XAxisPosition.BOTTOM); 
        xAxis.setDrawGridLines(false); 
        xAxis.setLabelCount(list1.size());list1.size()
        xAxis.setTextSize(12f); 
        xAxis.setGranularity(1f);


        xAxis.setValueFormatter(new IAxisValueFormatter() {
            @Override
            public String getFormattedValue(float value, AxisBase axis) {
                if ((int) value < list1.size()) {
                    return list1.get((int) value);
                } else {
                    return "";
                }
            }
        });
        xAxis.setYOffset(5); 

       //设置y轴
        YAxis yAxis_right = barChart.getAxisRight();
        yAxis_right.setAxisMaximum(40f);
        yAxis_right.setAxisMinimum(35f); 
        yAxis_right.setEnabled(false); 

        YAxis yAxis_left = barChart.getAxisLeft();
        yAxis_left.setAxisMaximum(40f);
        yAxis_left.setAxisMinimum(35f);
        yAxis_left.setTextSize(15f);
    }

添加数据：

 1 private void setData() {
 2         myHelper=new DatabaseHelper(this);
 3         SQLiteDatabase db=myHelper.getWritableDatabase();
 4         List<IBarDataSet> sets = new ArrayList<>();
 5         List<BarEntry> barEntries = new ArrayList<>();
 6         float[] num = new float[list1.size()];  //存放各班级正常填报的人数
 7 
 8         Cursor cursor = db.query("ALL_information", null, "name=?", new String[]{username}, null, null, null);//读取数据库所有信息
 9         if(cursor.moveToFirst()){
10             float i=0;
11             do{
12 
13                 String date=cursor.getString(cursor.getColumnIndex("date"));
14                 String temperature = cursor.getString(cursor.getColumnIndex("temperature"));
15                 float t=Float.parseFloat(temperature);
16                 barEntries.add(new BarEntry(i,t));
17                 i++;
18 
19             }while (cursor.moveToNext());
20         }
21         cursor.close();
22 
23         BarDataSet barDataSet = new BarDataSet(barEntries, "每日体温"); 
24         barDataSet.setValueTextColor(Color.BLACK); 
25         barDataSet.setValueTextSize(15f); 
26         barDataSet.setColor(Color.parseColor("#FFFF00")); 
27         
28 
29         barDataSet.setValueFormatter(new IValueFormatter() {
30             @Override
31             public String getFormattedValue(float value, Entry entry, int dataSetIndex, ViewPortHandler viewPortHandler) {
32                 return value + "℃";
33             }
34         });
35 
36         sets.add(barDataSet);
37         BarData barData = new BarData(sets);
38         barData.setBarWidth(0.6f); 
39         barChart.setData(barData);
40         barChart.getXAxis().setLabelRotationAngle(-60);  
41         barChart.setVisibleXRange(0,6); 
42 
43     }

二、运行结果

posted on 2021-03-19 09:46 戈瑾阅读(82) 评论(0) 收藏举报

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