App Inventor 不能编译这个项目编译器的错误输出是________Preparing application icon________Creating animation xml________Creating style xml________Generating manifest file________Attaching native libraries________Attaching Android Archive (AAR) libraries________Attaching component assets________Invoking AAPTAAPT time: 0.269 seconds________Compiling source files(compiling appinventor/ai_3051247810/shouying_zhengshiban/Screen1.yail to appinventor.ai_3051247810.shouying_zhengshiban.Screen1)(compiling appinventor/ai_3051247810/shouying_zhengshiban/System.yail to appinventor.ai_3051247810.shouying_zhengshiban.System)(compiling appinventor/ai_3051247810/shouying_zhengshiban/Kouling.yail to appinventor.ai_3051247810.shouying_zhengshiban.Kouling)(compiling appinventor/ai_3051247810/shouying_zhengshiban/Shangping.yail to appinventor.ai_3051247810.shouying_zhengshiban.Shangping)ERROR: appinventor/ai_3051247810/shouying_zhengshiban/Shangping.yail line 9: body with no expressionsERROR: appinventor/ai_3051247810/shouying_zhengshiban/Shangping.yail line 9: body with no expressionsKawa compile time: 1.106 seconds

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