Logcat不会显示log.d消息

Question

我正在开发一个Android应用程序，我想有一些方式打印调试语句，因为我的代码运行。对我来说幸运的是，当我在Android 2.3.3(API10)模拟器上运行应用程序时，Logcat能够打印出log.d消息。

然而，当我在物理设备（三星Galaxy S4 Android 4.2.2)上测试相同的应用程序时，除了dalvikvm和AndroidRuntime消息之外，我看不到其他任何东西。

com.android.internal.os.RuntimeInit <<<<<<
07-28 04:49:24.165: DEBUG/AndroidRuntime(6378): CheckJNI is OFF
07-28 04:49:24.165: DEBUG/AndroidRuntime(6378): setted country_code = USA
07-28 04:49:24.165: DEBUG/AndroidRuntime(6378): setted countryiso_code = US
07-28 04:49:24.175: DEBUG/AndroidRuntime(6378): setted sales_code = VZW
07-28 04:49:24.175: DEBUG/AndroidRuntime(6378): readGMSProperty: start
07-28 04:49:24.175: DEBUG/AndroidRuntime(6378): readGMSProperty: already setted!!
07-28 04:49:24.175: DEBUG/AndroidRuntime(6378): readGMSProperty: end
07-28 04:49:24.175: DEBUG/AndroidRuntime(6378): addProductProperty: start
07-28 04:49:24.185: DEBUG/dalvikvm(6378): Trying to load lib libjavacore.so 0x0
07-28 04:49:24.185: DEBUG/dalvikvm(6378): Added shared lib libjavacore.so 0x0
07-28 04:49:24.195: DEBUG/dalvikvm(6378): Trying to load lib libnativehelper.so 0x0
07-28 04:49:24.195: DEBUG/dalvikvm(6378): Added shared lib libnativehelper.so 0x0
07-28 04:49:24.385: DEBUG/AndroidRuntime(6378): Calling main entry com.android.commands.pm.Pm
07-28 04:49:26.978: DEBUG/AndroidRuntime(6378): Shutting down VM
07-28 04:49:26.988: DEBUG/dalvikvm(6378): GC_CONCURRENT freed 157K, 21% free 627K/788K, paused 1ms+0ms, total 4ms
07-28 04:49:26.988: DEBUG/jdwp(6378): Got wake-up signal, bailing out of select
07-28 04:49:26.988: DEBUG/dalvikvm(6378): Debugger has detached; object registry had 1 entries
07-28 04:49:27.458: DEBUG/AndroidRuntime(6420): >>>>>> AndroidRuntime START com.android.internal.os.RuntimeInit <<<<<<
07-28 04:49:27.458: DEBUG/AndroidRuntime(6420): CheckJNI is OFF
07-28 04:49:27.458: DEBUG/AndroidRuntime(6420): setted country_code = USA
07-28 04:49:27.458: DEBUG/AndroidRuntime(6420): setted countryiso_code = US
07-28 04:49:27.458: DEBUG/AndroidRuntime(6420): setted sales_code = VZW
07-28 04:49:27.458: DEBUG/AndroidRuntime(6420): readGMSProperty: start
07-28 04:49:27.458: DEBUG/AndroidRuntime(6420): readGMSProperty: already setted!!
07-28 04:49:27.458: DEBUG/AndroidRuntime(6420): readGMSProperty: end
07-28 04:49:27.458: DEBUG/AndroidRuntime(6420): addProductProperty: start
07-28 04:49:27.468: DEBUG/dalvikvm(6420): Trying to load lib libjavacore.so 0x0
07-28 04:49:27.478: DEBUG/dalvikvm(6420): Added shared lib libjavacore.so 0x0
07-28 04:49:27.478: DEBUG/dalvikvm(6420): Trying to load lib libnativehelper.so 0x0
07-28 04:49:27.478: DEBUG/dalvikvm(6420): Added shared lib libnativehelper.so 0x0
07-28 04:49:27.649: DEBUG/AndroidRuntime(6420): Calling main entry com.android.commands.am.Am
07-28 04:49:27.659: DEBUG/dalvikvm(6420): Note: class Landroid/app/ActivityManagerNative; has 169 unimplemented (abstract) methods
07-28 04:49:27.719: DEBUG/AndroidRuntime(6420): Shutting down VM
07-28 04:49:27.729: DEBUG/dalvikvm(6420): GC_CONCURRENT freed 157K, 20% free 666K/828K, paused 0ms+1ms, total 3ms
07-28 04:49:27.729: DEBUG/jdwp(6420): Got wake-up signal, bailing out of select
07-28 04:49:27.729: DEBUG/dalvikvm(6420): Debugger has detached; object registry had 1 entries

我不确定到底发生了什么，因为Logcat正确地瞄准了我的物理设备，它出现在adb设备上，USB调试是打开的。

编辑：我在Android4.2.2模拟器上尝试了同样的应用程序，Logcat和模拟器一样工作，但通过USB设备使用Logcat仍然有问题。与普通Logcat打印输出的冗长不同，我发布的块是我在冗长日志级别上看到的唯一东西。

Answer 1

这可能是因为一些手机禁用了日志，以提高性能。

例如，我的手机华为P9 lite，我必须执行以下步骤才能使log.d工作：

• 拨号*#*#2846579#*#*
  • 号码可能会有所不同，您应该进行一些搜索以获得手机的密码。

  

  open '/dev/hwlog_switch' fail -1, 13. Permission denied
  log switch off, only log_main and log_events will have logs!