相信众多android开发者在开发程序的过程中会经常用到Log打印信息
以方便了解当前程序的运行状况以及在出现BUG的时候能够快速定位问题
大多数童鞋会使用官方的打印log的方法，设置TAG，然后在Eclipse里面设置过滤标签，切换来回的看Log，但这样却效率很低；
下面分享一个Log打印信息的封装类，主要提供以下功能：
1.使用一个标签来标记当前的AP（避免设置过多的TAG来过滤显示不同Java文件下的Log）
2.显示当前的线程ID，用于辨别主线程还是子线程
3.显示当前的Java文件与打印log的行号，便于快速定位到源文件
4.最后显示你设置打印出来的信息
不罗嗦，上代码：
public class CommonLog { private String tag = "CommonLog"; public static int logLevel = Log.VERBOSE; public static boolean isDebug = true; public CommonLog() { } public CommonLog(String tag) { this.tag = tag; } public void setTag(String tag) { this.tag = tag; } private String getFunctionName() { StackTraceElement[] sts = Thread.currentThread().getStackTrace(); if (sts == null) { return null; } for (StackTraceElement st:sts) { if (st.isNativeMethod()) { continue; } if (st.getClassName().equals(Thread.class.getName())) { continue; } if (st.getClassName().equals(this.getClass().getName())) { continue; } return "["+Thread.currentThread().getName()+"("+Thread.currentThread().getId()+"): "+st.getFileName()+":"+st.getLineNumber()+"]"; } return null; } public void info(Object str) { if (logLevel <= Log.INFO) { String name = getFunctionName(); String ls=(name==null?str.toString():(name+" - "+str)); Log.i(tag, ls); } } public void i(Object str) { if (isDebug) { info(str); } } public void verbose(Object str) { if (logLevel <= Log.VERBOSE) { String name = getFunctionName(); String ls=(name==null?str.toString():(name+" - "+str)); Log.v(tag, ls); } } public void v(Object str) { if (isDebug) { verbose(str); } } public void warn(Object str) { if (logLevel <= Log.WARN) { String name = getFunctionName(); String ls=(name==null?str.toString():(name+" - "+str)); Log.w(tag, ls); } } public void w(Object str) { if (isDebug) { warn(str); } } public void error(Object str) { if (logLevel <= Log.ERROR) { String name = getFunctionName(); String ls=(name==null?str.toString():(name+" - "+str)); Log.e(tag, ls); } } public void error(Exception ex) { if (logLevel <= Log.ERROR) { StringBuffer sb = new StringBuffer(); String name = getFunctionName(); StackTraceElement[] sts = ex.getStackTrace(); if (name != null) { sb.append(name+" - "+ex+"\r\n"); } else { sb.append(ex+"\r\n"); } if (sts != null && sts.length > 0) { for (StackTraceElement st:sts) { if (st != null) { sb.append("[ "+st.getFileName()+":"+st.getLineNumber()+" ]\r\n"); } } } Log.e(tag, sb.toString()); } } public void e(Object str) { if (isDebug) { error(str); } } public void e(Exception ex) { if (isDebug) { error(ex); } } public void debug(Object str) { if (logLevel <= Log.DEBUG) { String name = getFunctionName(); String ls = (name == null?str.toString():(name+" - "+str)); Log.d(tag, ls); } } public void d(Object str) { if (isDebug) { debug(str); } }}
看ACTIVITY里的调用：
public class DebugDemoActivity extends Activity implements OnClickListener{ /** Called when the activity is first created. */ private CommonLog mCommonLog = LogFactory.createLog(); private Button mBtn1; private Button mBtn2; public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); initView(); mCommonLog.e("onCreate..."); } @Override protected void onStart() { // TODO Auto-generated method stub super.onStart(); mCommonLog.e("onStart..."); } @Override protected void onResume() { // TODO Auto-generated method stub super.onResume(); mCommonLog.e("onResume..."); } @Override protected void onPause() { // TODO Auto-generated method stub super.onPause(); mCommonLog.e("onPause..."); } @Override protected void onStop() { // TODO Auto-generated method stub super.onStop(); mCommonLog.e("onStop..."); } @Override protected void onDestroy() { // TODO Auto-generated method stub super.onDestroy(); mCommonLog.e("onDestroy..."); } public void initView() { mBtn1 = (Button) findViewById(R.id.button1); mBtn1.setOnClickListener(this); mBtn2 = (Button) findViewById(R.id.button2); mBtn2.setOnClickListener(this); } @Override public void onClick(View view) { // TODO Auto-generated method stub switch(view.getId()) { case R.id.button1: { mCommonLog.e("R.id.button1 onClick..."); } break; case R.id.button2: { SubThread subThread = new SubThread(); subThread.start(); } break; default: break; } }}最后看效果图：
下面附上工程链接：
http://download.csdn.net/detail/geniuseoe2012/4470104
欲了解更多android logcat的使用，请看这篇博文：
http://blog.csdn.net/geniuseoe2012/article/details/7820366