Android浏览器插件开发-Log

2011-08-24 11:33 1876人阅读 评论(1) 收藏 举报

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    android中的插件开发中的示例代码已经给我们说明了如何打log，参看示例代码main.cpp

 for (int i = 0; i < argc; i++) {
     if (!strcmp(argn[i], "DrawingModel")) {
         if (!strcmp(argv[i], "Bitmap")) {
             model = kBitmap_ANPDrawingModel;
         }
         else if (!strcmp(argv[i], "Surface")) {
            model = kSurface_ANPDrawingModel;
         }
         gLogI.log(kDebug_ANPLogType, "------ %p DrawingModel is %d", instance, model);
         break;
     }
 }

    我们可以使用gLogI.log打印调试信息。

    gLogI的定义如下

 ANPLogInterfaceV0           gLogI;

     ANPLogInterfaceV0的定义如下(Android_npapi.h)

 struct ANPLogInterfaceV0 : ANPInterface {
     /** dumps printf messages to the log file
         e.g. interface->log(instance, kWarning_ANPLogType, "value is %d", value);
      */
     void (*log)(ANPLogType, const char format[], ...);
 };

       该结构的赋值如下（ANPLogInterface.cpp）

 static void anp_log(ANPLogType logType, const char format[], ...) {
     va_list args;
     va_start(args, format);

     android_LogPriority priority;
     switch (logType) {
         case kError_ANPLogType:
             priority = ANDROID_LOG_ERROR;
             break;
         case kWarning_ANPLogType:
             priority = ANDROID_LOG_WARN;
             break;
         case kDebug_ANPLogType:
             priority = ANDROID_LOG_DEBUG;
             break;
         default:
             priority = ANDROID_LOG_UNKNOWN;
             break;
     }
     LOG_PRI_VA(priority, "plugin", format, args);

     va_end(args);
 }

 void ANPLogInterfaceV0_Init(ANPInterface* value) {
     ANPLogInterfaceV0* i = reinterpret_cast<ANPLogInterfaceV0*>(value);

     i->log = anp_log;
 }

    而LOG_PRI_VA的调用关系如下 

 [email protected]
 [email protected]
  [email protected]
 __android_log_write@logd_write.c
 write_to_log@logd_write.c
 __write_to_log_init@logd_write.c
 __write_to_log_kernel@logd_write.c
 [email protected]

    注：

    1. 插件的打印信息的channel为plugin

    2. android系统据我所知，只有如下log会受到是否打开DEBUG的影响

         LOGV*  LOG_FATAL*