先来个效果图吧
然后直接上代码,解说以后有机会我再补上
assets>index.html
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<script src="./js/echarts.min.js"></script>
<title>Document</title>
</head>
<body>
<div id="main" style="width: 400px;height:400px;"></div>
<script type="text/javascript" src="./js/echarts.min.js"></script>
<script>
var myChart = echarts.init(document.getElementById('main'));
function updateData(jsonstr) {
var shuju = JSON.parse(jsonstr);
option = {
xAxis: {
type: 'category',
data: shuju.data,
},
yAxis: {
type: 'value'
},
series: [{
data: shuju.wendu,
type: 'line'
}]
};
myChart.setOption(option);
}
</script>
</body>
</html>
Mainactivity.java
package cn.lanol.wendu;
import androidx.annotation.NonNull;
import androidx.annotation.UiThread;
import androidx.appcompat.app.AppCompatActivity;
import android.annotation.SuppressLint;
import android.content.ContentValues;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.webkit.JavascriptInterface;
import android.webkit.WebView;
import android.widget.Button;
import com.google.gson.Gson;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParser;
import java.io.IOException;
import java.sql.Time;
import java.util.Timer;
import java.util.TimerTask;
import cn.lanol.wendu.Helper.GetContext;
import cn.lanol.wendu.Helper.SQLiteDBhelper;
import okhttp3.OkHttpClient;
import okhttp3.Request;
import okhttp3.Response;
public class MainActivity extends AppCompatActivity {
private SQLiteDBhelper dBhelper = new SQLiteDBhelper(GetContext.getContext(), "DATA", null, 1);
private SQLiteDatabase db = dBhelper.getReadableDatabase();
private WebView webView;
private Handler handler;
@SuppressLint({"SetJavaScriptEnabled", "HandlerLeak"})
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//初始化数据库
new Thread(new Runnable() {
@Override
public void run() {
Timer timer = new Timer();
timer.schedule(new TimerTask() {
@Override
public void run() {
getWenDuData();
Message msg = new Message();
msg.what = 1;
handler.sendMessage(msg);
}
}, 0, 60000);
}
}).start();
webView = findViewById(R.id.echartsView);
webView.getSettings().setAllowFileAccess(true);
webView.getSettings().setJavaScriptEnabled(true);
webView.loadUrl("file:///android_asset/index.html");
handler = new Handler() {
@Override
public void handleMessage(@NonNull Message msg) {
super.handleMessage(msg);
Log.d("标签", "handleMessage: " + msg.what);
webView.loadUrl("javascript:updateData('" + getNewData() + "')");
}
};
try {
Thread.sleep(2000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
public String getNewData() {
dBhelper.getWritableDatabase();
String wenduJson = "[";
String timeJson = "[";
Cursor a = db.query("WenDu", null, null, null, null, null, "ID desc", "5");
if (a.moveToFirst()) {
do {
String time = a.getString(a.getColumnIndex("time"));
String wendu = a.getString(a.getColumnIndex("wendu"));
wenduJson += """ + wendu + "",";
timeJson += """ + time + "",";
} while (a.moveToNext());
}
timeJson = timeJson.substring(0, timeJson.length() - 1) + ']';
wenduJson = wenduJson.substring(0, wenduJson.length() - 1) + ']';
String result = "{"data":" + timeJson + ","wendu":" + wenduJson + "}";
return result;
}
public void getWenDuData() {
OkHttpClient okHttpClient = new OkHttpClient();
Request request = new Request.Builder().url("https://api.565.ink/json").get().build();
try {
Response response = okHttpClient.newCall(request).execute();
String res = response.body().string();
JsonObject a = JsonParser.parseString(res).getAsJsonObject();
String time = a.get("time").getAsString();
String wendu = a.get("wendu").getAsString();
Cursor cursor = db.query("WenDu", null, "time like '%" + time + "%'", null, null, null, null);
if (cursor.moveToFirst()) {
Log.d("已存在", time);
} else {
ContentValues values = new ContentValues();
values.put("time", time);
values.put("wendu", wendu);
db.insert("WenDu", null, values);
Log.d("不存在", time);
}
Log.d("结果", time + "," + wendu);
} catch (IOException e) {
e.printStackTrace();
}
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.drawerlayout.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical"
tools:ignore="WebViewLayout">
<TextView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center"
android:text="温度" />
<WebView
android:id="@+id/echartsView"
android:layout_width="match_parent"
android:layout_height="400dp" />
</LinearLayout>
<com.google.android.material.navigation.NavigationView
android:id="@+id/navigationView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_gravity="start" />
</androidx.drawerlayout.widget.DrawerLayout>
AndroidMainifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="cn.lanol.wendu">
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="@style/AppTheme"
android:name=".Helper.GetContext"
tools:ignore="GoogleAppIndexingWarning">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
SQLiteDBHelper.java
package cn.lanol.wendu.Helper;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.widget.Toast;
import androidx.annotation.Nullable;
public class SQLiteDBhelper extends SQLiteOpenHelper {
private Context mcontext;
private static final String CREATE_WENDU = "create table WenDu(id integer primary key autoincrement,time text,wendu integer)";
public SQLiteDBhelper(@Nullable Context context, @Nullable String name, @Nullable SQLiteDatabase.CursorFactory factory, int version) {
super(context, name, factory, version);
mcontext = context;
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(CREATE_WENDU);
Toast.makeText(GetContext.getContext(), "欢迎使用温度实时监控系统", Toast.LENGTH_SHORT).show();
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
}
GetContext.java
package cn.lanol.wendu.Helper;
import android.app.Application;
import android.content.Context;
public class GetContext extends Application {
private static Context context;
@Override
public void onCreate() {
super.onCreate();
context = getApplicationContext();
}
public static Context getContext() {
return context;
}
}
目录结构