8种机械键盘轴体对比

本人程序员，要买一个写代码的键盘，请问红轴和茶轴怎么选？

参考文章: http://blog.csdn.net/yaoming168/article/details/51986751

http://blog.csdn.net/a34140974/article/details/50156193

一.介绍

在应用层监听通话状态只有三种，从TelephonyManager.java中注释可知这三种状态含义如下：

CALL_STATE_IDLE 空闲态(没有通话活动)

CALL_STATE_RINGING 包括响铃、第三方来电等待

CALL_STATE_OFFHOOK 包括dialing拨号中、active接通、hold挂起等

由上可知，active接通状态没有单独给出，所以我们无法得知电话是否接通了，

因此需要其它手段来获取更多的精确通话状态，遍查网络资料，一般有两种方法！

public class TelephonyManager {

/** Device call state: No activity. */

public static final int CALL_STATE_IDLE = 0;

/** Device call state: Ringing. A new call arrived and is

* ringing or waiting. In the latter case, another call is

* already active. */

public static final int CALL_STATE_RINGING = 1;

/** Device call state: Off-hook. At least one call exists

* that is dialing, active, or on hold, and no calls are ringing

* or waiting. */

public static final int CALL_STATE_OFFHOOK = 2;

}

二.监听9种通话状态

法一.使用系统api监听

条件:

1.需要权限android.permission.READ_PRECISE_PHONE_STATE、app打包时需要系统签名、安装在系统目录等

2.onPreciseCallStateChanged 精确通话回调api在android.jar中被hide了, 可以使用反射或没有被hide的android.jar解决

TelephonyManager telM = (TelephonyManager) getSystemService(TELEPHONY_SERVICE);

telM.listen(new PhoneStateListener(){

/**

* 当有精确通话状态时回调

* Callback invoked when precise device call state changes

* @hide 隐藏api,给系统app使用的

*/

@Override

public void onPreciseCallStateChanged(PreciseCallState callState) {

//当有精确通话状态时回调

}

}, PhoneStateListener.LISTEN_PRECISE_CALL_STATE); //需要权限android.permission.READ_PRECISE_PHONE_STATE

// 精确的九大通话状态

public class PreciseCallState implements Parcelable {

public static final int PRECISE_CALL_STATE_IDLE = 0; //通话空闲

public static final int PRECISE_CALL_STATE_ACTIVE = 1; //正在通话(活动中)

public static final int PRECISE_CALL_STATE_HOLDING = 2; //通话挂起(例如我和多个人通话,其中一个通话在活动,而其它通话就会进入挂起状态)

public static final int PRECISE_CALL_STATE_DIALING = 3; //拨号开始

public static final int PRECISE_CALL_STATE_ALERTING = 4; //正在呼出(提醒对方接电话)

public static final int PRECISE_CALL_STATE_INCOMING = 5; //对方来电

public static final int PRECISE_CALL_STATE_WAITING = 6; //第三方来电等待(例如我正在和某人通话,而其他人打入时就会就进入等待状态)

public static final int PRECISE_CALL_STATE_DISCONNECTED = 7; //挂断完成

public static final int PRECISE_CALL_STATE_DISCONNECTING = 8; //正在挂断

}

法二.读取Logcat通信日志

条件:

1.android 4.1以上需要root权限，android 4.1以下版本只需添加日志权限android.permission.READ_LOGS

2.读取通信状态：在root状态下执行命令 logcat -v time -b radio

logcat日志被划分为以下几个缓冲区

-b

main — 主日志缓冲区(默认,普通app应用)

radio — 无线/电话相关日志缓冲区

events — 事件相关日志缓冲区

system — 系统相关日志缓冲区

//正则表达式，匹配通话状态

Pattern ptn = Pattern.compile("(\d{2}\-\d{2}\s\d{2}\:\d{2}\:\d{2}\.\d{3}).*?GET_CURRENT_CALLS.*?,(\w+),");

//Pattern ptn = Pattern.compile("(\d{2}-\d{2}\s\d{2}:\d{2}:\d{2}\.\d{3}).*?qcril_qmi_voice_all_call_status_ind_hdlr:.call.state.(\d),");

//使用Root权限，执行logcat命令

Process process = Runtime.getRuntime().exec("su");

PrintWriter pw = new PrintWriter(process.getOutputStream());

pw.println("logcat -v time -b radio"); //logcat命令, -v 详细时间; -b radio 通信相关日志缓冲区

pw.flush();

//循环读取通话日志

BufferedReader br = new BufferedReader(new InputStreamReader(process.getInputStream()));

String strLine;

while ((strLine = br.readLine()) != null) {

Matcher matcher = ptn.matcher(strLine);

if (matcher.find()) {// 匹配结果

String time = matcher.group(1); //提取通话时间

String state = matcher.group(2); //提取通话状态

}

}

pw.close();

br.close();

process.destroy();

三.图解9种通话状态

简书: http://www.jianshu.com/p/a362404f850f

CSDN博客: http://blog.csdn.net/qq_32115439/article/details/78395537

GitHub博客: http://lioil.win/2017/10/30/Android-PhoneState.html

Coding博客: http://c.lioil.win/2017/10/30/Android-PhoneState.html