Android Question error when compile

hi
sorry for my english.
error when i compile with message with new instalation:
B4A Versi: 12.50
Kode parsing. (0.03s)
Java Versi: 8
Building folders structure. (0.03s)
Menjalankan tindakan khusus. (0.04s)
Kompilasi kode. (0.25s)
Menyusun kode tata letak. (0.02s)
Mengatur perpustakaan. (0.00s)
(AndroidX SDK)
Compiling resources (0.07s)
Linking resources (0.23s)
Mengkompilasi kode mesin debugger. (1.96s)
Kompilasi kode Java yang dihasilkan. (1.79s)
Finding libraries that need to be dexed. (0.00s)
Dex code Error
Error in C:\testandroid\test1\B4A\Objects\bin\classes\b4a\example\main$B4AMenuItemsClickListener.class:
java.lang.NullPointerException: Cannot invoke "String.length()" because "<parameter1>" is null
Compilation failed with an internal error.
Exception in thread "main" java.lang.RuntimeException: com.android.tools.r8.CompilationFailedException: Compilation failed to complete, origin: C:\testandroid\test1\B4A\Objects\bin\classes\b4a\example\main$B4AMenuItemsClickListener.class
at com.android.tools.r8.internal.vj.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:98)
at com.android.tools.r8.D8.main(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:4)
Caused by: com.android.tools.r8.CompilationFailedException: Compilation failed to complete, origin: C:\testandroid\test1\B4A\Objects\bin\classes\b4a\example\main$B4AMenuItemsClickListener.class
at Version.fakeStackEntry(Version_3.3.20-dev+aosp1.java:0)
at com.android.tools.r8.internal.vj.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:75)
at com.android.tools.r8.internal.vj.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:28)
at com.android.tools.r8.internal.vj.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:27)
at com.android.tools.r8.internal.vj.b(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:2)
at com.android.tools.r8.D8.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:22)
at com.android.tools.r8.D8.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:17)
at com.android.tools.r8.internal.vj.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:85)
... 1 more
Caused by: java.lang.NullPointerException: Cannot invoke "String.length()" because "<parameter1>" is null
at com.android.tools.r8.graph.d1.<init>(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:5)
at com.android.tools.r8.graph.v0.b(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:12)
at com.android.tools.r8.graph.w2.b(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:9)
at com.android.tools.r8.internal.La.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:873)
at com.android.tools.r8.graph.x2.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:30)
at com.android.tools.r8.internal.vj.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:101)
at com.android.tools.r8.internal.vj.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:102)
at com.android.tools.r8.internal.vj.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:100)
at com.android.tools.r8.graph.x2.b(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:2)
at com.android.tools.r8.dex.a.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:26)
at java.base/java.util.concurrent.ForkJoinTask$AdaptedCallable.exec(ForkJoinTask.java:1456)
at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:387)
at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1312)
at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1843)
at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1808)
at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:188)
Suppressed: java.lang.RuntimeException: java.util.concurrent.ExecutionException: com.android.tools.r8.internal.xj: java.lang.NullPointerException: Cannot invoke "String.length()" because "<parameter1>" is null
at com.android.tools.r8.dex.b.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:107)
at com.android.tools.r8.dex.b.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:28)
at com.android.tools.r8.D8.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:25)
at com.android.tools.r8.D8.d(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:609)
at com.android.tools.r8.D8.c(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:1)
at com.android.tools.r8.internal.vj.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:24)
at com.android.tools.r8.internal.vj.b(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:2)
at com.android.tools.r8.D8.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:22)
at com.android.tools.r8.D8.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:17)
at com.android.tools.r8.internal.vj.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:85)
at com.android.tools.r8.D8.main(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:4)
Caused by: java.util.concurrent.ExecutionException: com.android.tools.r8.internal.xj: java.lang.NullPointerException: Cannot invoke "String.length()" because "<parameter1>" is null
at java.base/java.util.concurrent.ForkJoinTask.reportExecutionException(ForkJoinTask.java:581)
at java.base/java.util.concurrent.ForkJoinTask.get(ForkJoinTask.java:993)
at com.android.tools.r8.utils.C.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:56)
at com.android.tools.r8.dex.b.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:88)
... 10 more
Caused by: com.android.tools.r8.internal.xj: java.lang.NullPointerException: Cannot invoke "String.length()" because "<parameter1>" is null
at com.android.tools.r8.internal.xj.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:6)
at com.android.tools.r8.internal.vj.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:104)
at com.android.tools.r8.internal.vj.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:100)
at com.android.tools.r8.graph.x2.b(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:2)
at com.android.tools.r8.dex.a.a(R8_3.3.20-dev+aosp1_dd4c01853fd917497aef2d09abff533f0d25b062517ea74449d40e1778a34753:26)
at java.base/java.util.concurrent.ForkJoinTask$AdaptedCallable.exec(ForkJoinTask.java:1456)
at java.base/java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:387)
at java.base/java.util.concurrent.ForkJoinPool$WorkQueue.topLevelExec(ForkJoinPool.java:1312)
at java.base/java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1843)
at java.base/java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1808)
at java.base/java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:188)
Caused by: [CIRCULAR REFERENCE: java.lang.NullPointerException: Cannot invoke "String.length()" because "<parameter1>" is null]