[英]Room Persistence lib implementation in Kotlin(Gradle error)
我正在kotlin中實現Room persistence lib來實現我的數據庫。 在Android Room Persistences庫和Kotlin線程中詢問相同的問題,應用這些解決方案會導致不同的gradle錯誤:
以下是我的Entity
, Dao
和Database
類:
Food.kt
@Entity
class Food(@ColumnInfo(name = "food_name") var foodName: String,
@ColumnInfo(name = "food_desc") var foodDesc: String,
@ColumnInfo(name = "protein") var protein: Double,
@ColumnInfo(name = "carbs") var carbs: Double,
@ColumnInfo(name = "fat") var fat: Double)
{
@ColumnInfo(name = "id")
@PrimaryKey(autoGenerate = true)
var id: Long = 0
@ColumnInfo(name = "calories")
var calories: Double = 0.toDouble()
}
PersonalizedFood.kt
@Entity(primaryKeys = arrayOf("food_id","date"))
class PersonalizedFood(@ColumnInfo(name = "quantity") var quantity: Int,
@ColumnInfo(name = "unit") var unit: String,
@ColumnInfo(name = "date") var date: Date){
@ColumnInfo(name = "food_id")
var foodId:Long = 0
}
FoodDao.kt
@Dao
interface FoodDao {
companion object{
const val ID = "id"
const val NAME = "name"
const val PROTEIN = "protein"
const val DESC = "desc"
const val CARBS = "carbs"
const val FAT = "fat"
const val DATE = "date"
const val FOOD_ID = "food_id"
const val ALL_FOOD_LIST = "food"
const val PERSONALISED_FOOD_LIST = "personalised_food"
}
/**
* Returns food details of a food given by food_id
*/
@Query("SELECT * FROM $ALL_FOOD_LIST WHERE $ID=:food_id")
fun getFoodDetails(food_id:Long):Food
/**
* Inserts food items in all_food_list
*/
@Insert
fun addFoodList(list:ArrayList<Food>)
@Insert(onConflict = REPLACE)
fun saveFood(food:PersonalizedFood)
@Query("SELECT * FROM $PERSONALISED_FOOD_LIST WHERE $FOOD_ID=:foodId and $DATE=:date")
fun getFood(foodId:Int, data:Date):PersonalizedFood
@Query("SELECT * FROM $ALL_FOOD_LIST where $ID in (select $FOOD_ID from $PERSONALISED_FOOD_LIST where $DATE = :date)")
fun getFood(date:Date):ArrayList<Food>
}
Converter.kt
class Converter {
companion object{
@TypeConverter
fun fromTimestamp(value: Long?): Date? {
return if (value == null) null else Date(value)
}
@TypeConverter
fun dateToTimestamp(date: Date): Long {
return date.time
}
}
}
FoodDatabase.kt
@Database(entities = arrayOf(Food::class, PersonalizedFood::class), version = 1)
@TypeConverters(Converter::class)
abstract class FoodDatabase : RoomDatabase(){
abstract fun foodDao():FoodDao
companion object{
private val databaseName = "diet"
var dbInstance:FoodDao? = null
fun getInstance(context:Context):FoodDao?{
if(dbInstance == null)
dbInstance = Room.inMemoryDatabaseBuilder(context, FoodDatabase::class.java).build().foodDao()
return dbInstance;
}
}
}
當我運行以下代碼來創建數據庫時:
FoodDatabase.getInstance(baseContext)?.getFood(Calendar.getInstance().time)
它給了我以下例外:
Caused by: java.lang.RuntimeException: cannot find implementation for com.chandilsachin.diettracker.database.FoodDatabase. FoodDatabase_Impl does not exist
at android.arch.persistence.room.Room.getGeneratedImplementation(Room.java:90)
at android.arch.persistence.room.RoomDatabase$Builder.build(RoomDatabase.java:340)
at com.chandilsachin.diettracker.database.FoodDatabase$Companion.getInstance(FoodDatabase.kt:21)
at com.chandilsachin.diettracker.MainActivity$SetUpFoodDatabase.doInBackground(MainActivity.kt:95)
at com.chandilsachin.diettracker.MainActivity$SetUpFoodDatabase.doInBackground(MainActivity.kt:77)
at android.os.AsyncTask$2.call(AsyncTask.java:295)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:234)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
有沒有人在kotlin實施過房間持久性?
編輯
我以前對同一主題的問題被打上重復此 。 雖然問題陳述是相同的,但解決方案並沒有解決我的問題。 解決方案說我必須將替換annotationProcessor
添加到kapt "android.arch.persistence.room:compiler:1.0.0-alpha1"
依賴項。 我做了這些更改,導致項目構建時出現gradle錯誤。
Information:Gradle tasks [:app:assembleDebug]
Warning:warning: Supported source version 'RELEASE_7' from annotation processor 'android.arch.persistence.room.RoomProcessor' less than -source '1.8'
Warning:warning: The following options were not recognized by any processor: '[kapt.kotlin.generated]'
/Users/BBI-M1025/Documents/BBI/Workspace_fun/Android/diet-tracker/app/src/main/java/com/chandilsachin/diettracker/database/Food.kt
Error:(1, 1) Some error(s) occurred while processing annotations. Please see the error messages above.
Error:Execution failed for task ':app:kaptDebugKotlin'.
> Compilation error. See log for more details
Information:BUILD FAILED in 10s
Information:2 errors
Information:2 warnings
Information:See complete output in console
我也附上了我的gradle文件:
apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'
apply plugin: 'kotlin-kapt'
android {
compileSdkVersion 25
buildToolsVersion "25.0.2"
defaultConfig {
applicationId "com.chandilsachin.diettracker"
minSdkVersion 16
targetSdkVersion 25
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
exclude group: 'com.android.support', module: 'support-annotations'
})
compile "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version"
compile 'com.android.support:appcompat-v7:25.0.1'
compile 'com.android.support.constraint:constraint-layout:1.0.0-alpha8'
compile 'com.android.support:cardview-v7:25.0.1'
compile 'com.android.support:recyclerview-v7:25.0.1'
compile 'com.github.ne1c:rainbowmvp:1.2.1'
compile "org.jetbrains.anko:anko-commons:0.10.0"
/*annotationProcessor "android.arch.persistence.room:compiler:1.0.0-alpha1"
compile "android.arch.lifecycle:extensions:1.0.0-alpha1"
annotationProcessor "android.arch.lifecycle:compiler:1.0.0-alpha1"*/
compile "android.arch.persistence.room:runtime:1.0.0-alpha1"
annotationProcessor "android.arch.persistence.room:compiler:1.0.0-alpha1"
kapt "android.arch.persistence.room:compiler:1.0.0-alpha1"
testCompile 'junit:junit:4.12'
}
repositories {
mavenCentral()
}
有人遇到過這個問題嗎?
在我解決這個問題一段時間之后,我找到了解決方案。
這真的很難,因為目前沒有官方教程,博客等幫助解決這個問題。
我必須為gradle插件和依賴項的所有組合做幾次命中和試用,因為我知道gradle配置只有一些問題。
讓我們來解決方案:
我不得不從build.gradle(:module)文件中刪除apply plugin: 'kotlin-kapt'
,並將annotationProcessor "android.arch.persistence.room:compiler:1.0.0-alpha1"
替換為kapt "android.arch.persistence.room:compiler:1.0.0-alpha1"
。
這是成功編譯代碼的gradle配置。
但還有更多事情需要檢查。 與Room Persistence lib doc中給出的java不同,您必須初始化@Entity class
屬性。 雖然有getter setter但是沒有提到創建一個帶初始化的構造函數。 所以我不得不改變我的@Entity
類:
@Entity(tableName = "all_food_list")
class Food (@ColumnInfo(name = "food_name") var foodName: String = "",
@ColumnInfo(name = "food_desc") var foodDesc: String = "",
@ColumnInfo(name = "protein") var protein: Double = 0.0,
@ColumnInfo(name = "carbs") var carbs: Double = 0.0,
@ColumnInfo(name = "fat") var fat: Double = 0.0,
@ColumnInfo(name = "calories") var calories: Double = 0.0)
{
@ColumnInfo(name = "id")
@PrimaryKey(autoGenerate = true)
var id: Long = 0
}
現在對於TypeConverts,與java不同,您需要創建普通函數而不是靜態函數(伴隨對象):
class Converters{
@TypeConverter
fun fromTimestamp(value: String): Calendar {
val arr = value.split("-")
val cal = Calendar.getInstance()
cal.set(arr[0].toInt(), arr[1].toInt(), arr[2].toInt())
return cal
}
@TypeConverter
fun dateToTimestamp(date: Calendar): String {
return "${date.get(Calendar.DATE)}-${date.get(Calendar.MONTH)+1}-${date.get(Calendar.YEAR)}"
}
}
我正在添加build.gradle文件以使其更清晰:
的build.gradle(:項目)
buildscript {
ext.kotlin_version = '1.1.2-4'
ext.gradle_version_stable = '2.3.2'
ext.gradle_version_preview = '3.0.0-alpha1'
ext.anko_version = '0.10.0'
repositories {
maven { url 'https://maven.google.com' }
jcenter()
}
dependencies {
classpath 'com.android.tools.build:gradle:3.0.0-alpha1'
classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
// NOTE: Do not place your application dependencies here; they belong
// in the individual module build.gradle files
}
}
allprojects {
repositories {
maven { url 'https://maven.google.com' }
jcenter()
maven { url "https://jitpack.io" }
}
}
task clean(type: Delete) {
delete rootProject.buildDir
}
的build.gradle(:模塊)
apply plugin: 'com.android.application'
apply plugin: 'kotlin-android'
apply plugin: 'kotlin-android-extensions'
android {
compileSdkVersion 25
buildToolsVersion "25.0.2"
defaultConfig {
applicationId "com.chandilsachin.diettracker"
minSdkVersion 16
targetSdkVersion 25
versionCode 1
versionName "1.0"
testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
}
buildTypes {
release {
minifyEnabled false
proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
}
}
}
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
androidTestCompile('com.android.support.test.espresso:espresso-core:2.2.2', {
exclude group: 'com.android.support', module: 'support-annotations'
})
compile "org.jetbrains.kotlin:kotlin-stdlib-jre7:$kotlin_version"
...
...
// room persistence dependency
compile "android.arch.persistence.room:runtime:1.0.0-alpha1"
kapt "android.arch.persistence.room:compiler:1.0.0-alpha1"
testCompile 'junit:junit:4.12'
}
repositories {
mavenCentral()
}
我想這就是全部,我做了我的代碼。
希望這也有助於其他人。
man只需在build.gradle中添加以下內容即可。 以上依賴關系:D
kapt {
generateStubs = true
}
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