Android 读sys/class/power_supply/battery/cureent_now的值
发布日期:2021-06-30 18:52:38
浏览次数:2
分类:技术文章
本文共 4207 字,大约阅读时间需要 14 分钟。
package com.example.readsysclass;import java.io.ByteArrayOutputStream;import java.io.File;import java.io.FileInputStream;import java.io.IOException;import java.io.InputStream;import android.app.Activity;import android.os.Bundle;import android.os.Handler;import android.util.Log;import android.view.View;import android.view.View.OnClickListener;import android.widget.Button;import android.widget.TextView;public class MainActivity extends Activity { Button button01; TextView text01; private int TIME = 2000; static final String TAG="readsysclass"; private static final String CHARGER_CURRENT_NOW = "/sys/class/power_supply/battery/current_now"; /** * Read a text file into a String, optionally limiting the length. * * @param file to read (will not seek, so things like /proc files are OK) * @param max length (positive for head, negative of tail, 0 for no limit) * @param ellipsis to add of the file was truncated (can be null) * @return the contents of the file, possibly truncated * @throws IOException if something goes wrong reading the file */ public static String readTextFile(File file, int max, String ellipsis) throws IOException { InputStream input = new FileInputStream(file); try { long size = file.length(); if (max > 0 || (size > 0 && max == 0)) { // "head" mode: read the first N bytes if (size > 0 && (max == 0 || size < max)) max = (int) size; byte[] data = new byte[max + 1]; int length = input.read(data); if (length <= 0) return ""; if (length <= max) return new String(data, 0, length); if (ellipsis == null) return new String(data, 0, max); return new String(data, 0, max) + ellipsis; } else if (max < 0) { // "tail" mode: keep the last N int len; boolean rolled = false; byte[] last = null, data = null; do { if (last != null) rolled = true; byte[] tmp = last; last = data; data = tmp; if (data == null) data = new byte[-max]; len = input.read(data); } while (len == data.length); if (last == null && len <= 0) return ""; if (last == null) return new String(data, 0, len); if (len > 0) { rolled = true; System.arraycopy(last, len, last, 0, last.length - len); System.arraycopy(data, 0, last, last.length - len, len); } if (ellipsis == null || !rolled) return new String(last); return ellipsis + new String(last); } else { // "cat" mode: size unknown, read it all in streaming fashion ByteArrayOutputStream contents = new ByteArrayOutputStream(); int len; byte[] data = new byte[1024]; do { len = input.read(data); if (len > 0) contents.write(data, 0, len); } while (len == data.length); return contents.toString(); } } finally { input.close(); } } @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); button01 = (Button)findViewById(R.id.button01); text01 = (TextView)findViewById(R.id.text01); button01.setOnClickListener(new OnClickListener() { public void onClick(View arg0) { // TODO Auto-generated method stub handler.postDelayed(runnable, TIME); //每隔1s执行 } }); } Handler handler = new Handler(); Runnable runnable = new Runnable() { @Override public void run() { // TODO Auto-generated method stub handler.postDelayed(this, TIME); try { String mode1 = readTextFile(new File(CHARGER_CURRENT_NOW), 0, null).trim(); text01.setText(mode1); Log.e(TAG,mode1); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } };}
转载地址:https://linus.blog.csdn.net/article/details/43451171 如侵犯您的版权,请留言回复原文章的地址,我们会给您删除此文章,给您带来不便请您谅解!
发表评论
最新留言
逛到本站,mark一下
[***.202.152.39]2024年04月19日 02时02分06秒
关于作者
喝酒易醉,品茶养心,人生如梦,品茶悟道,何以解忧?唯有杜康!
-- 愿君每日到此一游!
推荐文章
tf dense layer两种创建方式的对比和numpy实现
2019-04-30
tf initializer
2019-04-30
tf 从RNN到BERT
2019-04-30
tf keras SimpleRNN源码解析
2019-04-30
tf keras Dense源码解析
2019-04-30
tf rnn输入输出的维度和权重的维度
2019-04-30
检验是否服从同一分布
2019-04-30
tf callbacks
2019-04-30
keras、tf、numpy实现logloss对比
2019-04-30
Ubuntu20.04安装微信
2019-04-30
Restful风格的使用
2019-04-30
Swagger基础入门整合SpringBoot
2019-04-30
MyBatisPlus简单入门(SpringBoot)
2019-04-30
攻防世界web进阶区NewsCenter详解
2019-04-30
攻防世界web进阶PHP2详解
2019-04-30
如何解决词达人问题(新)
2019-04-30
攻防世界web进阶区surpersqli详解
2019-04-30
攻防世界web进阶区easytornado详解
2019-04-30
攻防世界web进阶区web2详解
2019-04-30
xss-labs详解(上)1-10
2019-04-30