java - Print logs on Android source code using Eclipse breakpoints? -

in debug effort understand system doing use java debugger conditional breakpoints mechanism print log messages on specific lines in android's source code.

how it? don't know, that's question about.

things know:
eclipse java debugger has "conditional breakpoints", i.e., set breakpoint in code , write condition. each time code reaches breakpoint line stop execution if condition wrote true, otherwise not stop.

i though maybe mechanism can twisted print log message @ specific line in code instead of stopping execution. , if can done able track android's source code doing.

you can use following expression in conditional breakpoint:

android.util.log.v("myapp", "my message") == -1 

this make breakpoints not break execution , in logcat view, filtering view using tag:myapp expression, desired logged messages. can use other log levels (a, i, e, w). see log documentation more info.

to have breakpoint break, use:

android.util.log.v("myapp", "my message") >= 0 

the return value of log.v number of bytes log message internally has, positive number.

addendum: there more elegant way it. eclipse conditional breakpoints can java code, including using local variables @ breakpoint. last return value must true if want stop execution or false. same can achieved as:

android.util.log.v("myapp", "my message"); return false; 

or can make more complicated statements like:

if( t.isnumber() ) {     system.out.println("a number found"); } else {     system.out.println("not number");     return true; // stops execution } android.util.log.v("myapp", "my message"); return false; // not stop execution