kotlin

问题 Does Kotlin provide a mutation function to split a list when a specific predicate is true? In the following example the list should be split when the element is a . . The result should be of the type List<List<String>> . // input list val list = listOf( "This is", "the", "first sentence", ".", "And", "now there is", "a second", "one", ".", "Nice", "." ) // the following should be the result of the transformation listOf( listOf("This is", "the", "first sentence"), listOf("And", "now there is",

问题 I am using Firebase Auth in my app. I update the email like follows: firebaseAuth.currentUser?.updateEmail(email) The email is updating 100% (I do a re-auth when necessary as well). My problem is after the e-mail has changed, the user is being logged out of his account and has to login again. When I call val user = firebaseAuth.currentUser after updating the email the user is null and my app wants you to login again with the new email address. Is this the correct behaviour? It makes for a

问题 I have a .db file in assets folder. My RoomDatabase class is as the following. I install the app to my device. Then I changed version = 2 in the below class, and make my prepopulated database version 2. Then i renamed one of the columns in my table so that schema is changed. Then i installed the app again. And boom! Room gives me the following error : Room cannot verify the data integrity. Looks like you've changed schema but forgot to update the version number. You can simply fix this by

问题 I have a .db file in assets folder. My RoomDatabase class is as the following. I install the app to my device. Then I changed version = 2 in the below class, and make my prepopulated database version 2. Then i renamed one of the columns in my table so that schema is changed. Then i installed the app again. And boom! Room gives me the following error : Room cannot verify the data integrity. Looks like you've changed schema but forgot to update the version number. You can simply fix this by

问题 I want to ignore a field when using the @Parcelize annotation in Kotlin so that the field is not parceled, since this field does not implement the Parcelable interface. Starting with this, we get an error because PagedList is not parcelable: @Parcelize data class LeaderboardState( val progressShown: Boolean = true, val pagedList: PagedList<QUser>? = null ) : Parcelable Gives: Type is not directly supported by 'Parcelize'. Annotate the parameter type with '@RawValue' if you want it to be

问题 I want to ignore a field when using the @Parcelize annotation in Kotlin so that the field is not parceled, since this field does not implement the Parcelable interface. Starting with this, we get an error because PagedList is not parcelable: @Parcelize data class LeaderboardState( val progressShown: Boolean = true, val pagedList: PagedList<QUser>? = null ) : Parcelable Gives: Type is not directly supported by 'Parcelize'. Annotate the parameter type with '@RawValue' if you want it to be

问题 Im having trouble inheriting an interface containing a method/fun of a base type, that i would like to override as a subtype in the class implementing it. So far i have the interface interface IModel { fun convert(dataModel: BaseDataModel) } And the class implementing it: class SettingsModel: IModel { override fun convert(dataModel: BaseDataModel) { // Conversion of models here } } And i also have the SettingsDataModel which is: class SettingsDataModel: BaseDataModel() { } What i'm trying to

问题 I am trying to exclude a Kotlin property from deserialization using gson. I have tried different methods from annotating the property with @Transient to creating a custom annotation strategy (specifying the strategy in the gson builder of course), but nothing seems to be working, as the property keeps getting null instead of the value I initialized the property with. I have not tried using the @Expose annotation, but I do not want to annotate other fields with @Expose Please, how can I

问题 I am trying to exclude a Kotlin property from deserialization using gson. I have tried different methods from annotating the property with @Transient to creating a custom annotation strategy (specifying the strategy in the gson builder of course), but nothing seems to be working, as the property keeps getting null instead of the value I initialized the property with. I have not tried using the @Expose annotation, but I do not want to annotate other fields with @Expose Please, how can I

问题 I want to combine two different length lists. For example; val list1 = listOf(1,2,3,4,5) val list2 = listOf("a","b","c") I want to result like this (1,"a",2,"b",3,"c",4,5) Is there any suggestion? 回答1: You may use the .zip function for that list1.zip(list2){ a,b -> listOf(a,b)}.flatten() The only problem is that it will only process elements, with both sets, so if (like in the example) let's have different size - it will not work The alternative could be to add specific markers and filter