android里面的log输出以往都是在eclipse里面看，如果通过USB连接电脑，可以输出到PC上。

try {

//adb logcat -v threadtime > logcat.txt

String fileName = "logcat_" + System.currentTimeMillis() + ".txt";

File outputFile = new File(Environment.getExternalStorageDirectory(), fileName);

@SuppressWarnings("unused")

Process process = Runtime.getRuntime().exec(

"logcat -v threadtime -f" + outputFile.getAbsolutePath());

} catch (IOException e) {

}

bat:

adb logcat -v threadtime  > logcat.txt

参考文档：

Reading and Writing Logs

http://developer.android.com/tools/debugging/debugging-log.html

Android Debug Bridge, Part 1: How to Capture Logcat Files Using ADB

http://university.utest.com/android-debug-bridge-part-1-how-to-capture-logcat-files-using-adb/

write to file on sd card

http://stackoverflow.com/questions/6175002/write-android-logcat-data-to-a-file