kotlin语言里面取两个map的交集，可以直接用filterKeys()方法，如下：
val map1 = mapOf("1" to "1", "2" to "2")
val map2 = mapOf("2" to "2", "3" to "3")
val map3 = map1.filterKeys {
map2.keys.contains(it)
}
Log.d("Alex", "map1: $map1")
Log.d("Alex", "map2: $map2")
Log.d("Alex", "map3: $map3")打印如下：
2023-04-03 08:48:43.870 1934-1934/com.example.myapplication D/Alex: map1: {1=1, 2=2}
2023-04-03 08:48:43.870 1934-1934/com.example.myapplication D/Alex: map2: {2=2, 3=3}
2023-04-03 08:48:43.870 1934-1934/com.example.myapplication D/Alex: map3: {2=2}