求问关于Swarm产生柱状图的问题 多谢大家了！！

mushroom89

各位好，我想请教一下，我想产生一个柱状图，但是在buildActions（）好像selector那有问题，说
9 z) h8 t* _" S% Q0 I$ AThere was an error in creating a Selector for method step in Class swarm.analysis.EZDistributionImpl.
swarm.analysis.EZDistributionImpl.step returns null
The process will be terminated.
(Tcl -eval couldn't read file "F:Swarm-2.2-java/lib/tcl8.4//word.tcl": no such file or directory
: x8 _  C1 X. X9 B$ s/ ~5 Z    while executing
"source F:\Swarm-2.2-java/lib/tcl8.4//word.tcl"
5 h7 q6 v4 \, m- d1 U; N; Bwhile evaluating: source F:\Swarm-2.2-java/lib/tcl8.4//word.tcl
5 F4 h2 U; `" `( m*** event raised for warning: WarningMessage
+ }% o) B, `, i$ P# Y*** function: _i_ProbeMap__addProbe_(), file: /src/swarm/src/objectbase/ProbeMap.m, line: 606
: U4 G: g6 x  D* J1 g2 TAttempt to add null probe
) K7 M- ^2 O( q*** execution continuing...
请问第一个参数应该是什么呢 我设的是ezdist（一个EZDistribution object），
请问是怎么回事呢？多谢大家了~