调试android通过jni调用的C++代码

1、头文件

#include <android/log.h>

2、宏定义

#define LOGD(...) __android_log_print(ANDROID_LOG_DEBUG, "mytest", __VA_ARGS__)

3、代码中打印

LOGD("test test test");
int i = 12;
LOGD("%d",i);

4、注意

打印字符串可以用下面两个函数

__android_log_print

__android_log_write

但是打印整数等，就必须用下面这个函数了

__android_log_print

原因参见文件/system/core/include/android/log.h，如下

 1 #include <stdarg.h>
 2 
 3 #ifdef __cplusplus
 4 extern "C" {
 5 #endif
 6 
 7 /*
 8  * Android log priority values, in ascending priority order.
 9  */
10 typedef enum android_LogPriority {
11     ANDROID_LOG_UNKNOWN = 0,
12     ANDROID_LOG_DEFAULT,    /* only for SetMinPriority() */
13     ANDROID_LOG_VERBOSE,
14     ANDROID_LOG_DEBUG,
15     ANDROID_LOG_INFO,
16     ANDROID_LOG_WARN,
17     ANDROID_LOG_ERROR,
18     ANDROID_LOG_FATAL,
19     ANDROID_LOG_SILENT,     /* only for SetMinPriority(); must be last */
20 } android_LogPriority;
21 
22 /*
23  * Send a simple string to the log.
24  */
25 int __android_log_write(int prio, const char *tag, const char *text);
26 
27 /*
28  * Send a formatted string to the log, used like printf(fmt,...)
29  */
30 int __android_log_print(int prio, const char *tag,  const char *fmt, ...)
31 #if defined(__GNUC__)
32     __attribute__ ((format(printf, 3, 4)))
33 #endif
34     ;
35 
36 /*
37  * A variant of __android_log_print() that takes a va_list to list
38  * additional parameters.
39  */
40 int __android_log_vprint(int prio, const char *tag,
41                          const char *fmt, va_list ap);
42 
43 /*
44  * Log an assertion failure and SIGTRAP the process to have a chance
45  * to inspect it, if a debugger is attached. This uses the FATAL priority.
46  */
47 void __android_log_assert(const char *cond, const char *tag,
48               const char *fmt, ...)    
49 #if defined(__GNUC__)
50     __attribute__ ((noreturn))
51     __attribute__ ((format(printf, 3, 4)))
52 #endif
53     ;
54 
55 #ifdef __cplusplus
56 }
57 #endif
58 
59 #endif /* _ANDROID_LOG_H */