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Flutter provides print(Object object) to output log information to the console of the development tool

print("test");

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The basic data types that can be directly output by interpolation are as follows:

String str = "Zhang San" ;
 print ( "Test output $str " ) ;

int count =  40 ; 
print ( "Test output $count " ) ;

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If it is an object type, such as to output the value of a property of the object, you can do this:

 User user =  new  User ( name : "Zhang San" ) ;
 
 ///Output name 
 print ( "Test output ${user.name} " ) ;

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The common_utils tool class has encapsulated pring as a tool class

common_utils: ^1.1.1

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Use LogUtil from the common_utils tool class

//Initialize setting LogUtil 
LogUtil . init ( true ) ; 
// Output log 
LogUtil . v ( "test" ) ;

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Of course, the init method of LogUtil can configure true and false according to whether it is a production environment. If it is false, the log will not be output. Such an optimization can also save the consumption of outputting log information to the console after the version is released.

The package source code is as follows

class LogUtil {
  static const String _TAG_DEF = "###common_utils###";

  static bool debuggable =  false ;  //Whether it is debug mode, true: log v does not output. 
  static  String TAG = _TAG_DEF ;

  static void init({bool isDebug = false, String tag = _TAG_DEF}) {
    debuggable = isDebug;
    TAG = tag;
  }

  static void e(Object object, {String tag}) {
    _printLog(tag, '  e  ', object);
  }

  static void v(Object object, {String tag}) {
    if (debuggable) {
      _printLog(tag, '  v  ', object);
    }
  }

  static void _printLog(String tag, String stag, Object object) {
    StringBuffer sb = new StringBuffer();
    sb.write((tag == null || tag.isEmpty) ? TAG : tag);
    sb.write(stag);
    sb.write(object);
    print(sb.toString());
  }
}

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