The following code sample does not work anymore: val forecastList: RecyclerView = find(R.id.forecast_list)

Use this instead: val forecastList = find<RecyclerView>(R.id.forecast_list)

I have been following along in the book. When I added the code for Chapter 19, the DatabaseExtensions.kt file will not compile. To ensure that I didn't type something wrong, I got a zip of the Chapter 19 commit and got the same error:

• Error:(8, 19) Object must be declared abstract or implement abstract member public abstract fun parseRow(columns: Map<String, Any?>): T defined in org.jetbrains.anko.db.MapRowParser
• Error:(9, 13) 'parseRow' overrides nothing
• Error:(13, 18) Object must be declared abstract or implement abstract member public abstract fun parseRow(columns: Map<String, Any?>): T defined in org.jetbrains.anko.db.MapRowParser
• Error:(14, 13) 'parseRow' overrides nothing

I'm using buildVersonSdk 25.0.0, targetSdkVersion 25, ext.support_version 25.1.0, ext.kotlin_version 1.0.6, ext_anko_version 0.9 in Android Studio. Everything had worked up to the transition from earlier chapters to chapter 19. Since I'm new to Kotlin, I don't have a clue what is wrong or how to fix it.

When I run the app, an error was occurred by create database table DayForecastTable. This is the error: android.database.sqlite.SQLiteException: near "org": syntax error (code 1): , while compiling: CREATE TABLE IF NOT EXISTS DayForecast(id INTEGER PRIMARY KEY org.jetbrains.anko.db.SqlTypeModifierImpl@a5038ce, date INTEGER, description TEXT, high INTEGER, low INTEGER, iconUrl TEXT, cityId INTEGER); Why the AUTOINCREMENT cannot be recognized. My anko version is 0.10.1

In MainActivity.kt, starting with Chapter 8, the http link gives me this error in MainActivity->onCreate:

weatherapp W/System.err: java.io.IOException: Cleartext HTTP traffic to api.openweathermap.org not permitted

I propose changing the http://api.openweather... URL to https://api.openweather...

In the chapter-19 branch there is a mix-up between zip code and city id. The code compiles and runs because the database is not used. Nonetheless I believe there is an error. Here is what I think needs to change:

In ForecastDataMapper.convertFromDataModel the first parameter in the ForecastList constructor should be "city.id" instead of "zipCode". Additionally, the "zipCode" parameter should be removed from convertFromDataModel so that it takes only a ForecastResult.

Once this change is made the overridden function in RequestForecastCommand must be changed so the "zipCode" parameter is removed from the parameters passed to convertFromDataModel.

This will fix the issue, but I would also recommend changing the name of the "id" parameter on the ForecastList constructor to "cityId" to make it clearer what id this is.

This becomes a problem when the date of your time zone differs from the date of GMT time.

1. ForecastByZipCodeRequest obtains a weekly forecast starting with today in your current time zone.
2. ForecastDb.requestForecastByZipCode(zipCode, todayTimeSpan()) filters out the first row of DayForecastTable because its column DATE precedes todayTimeSpan().
3. ForecastProvider.requestByZipCode(zipCode, days) never returns a non-null value.

I am in America/New York (EDT GMT -04:00 DST) time zone. Here is a real example when I run the app:

• System.currentTimeMillis() is 1464056054644, or May 23, 2016 at 10:14:14 PM EDT GMT-4:00 DST
• todayTimeSpan() is 1464048000000, or May 23, 2016 at 8:00:00 PM EDT GMT-4:00 DST
• Date values for returned by OpenWeatherMap for seven-day forecast are: {1464001200000, 1464087600000, 1464174000000, 1464260400000, 1464346800000, 1464433200000, 1464519600000}
• Database only returns {1464087600000, 1464174000000, 1464260400000, 1464346800000, 1464433200000, 1464519600000}

Can't we use Anko for the RecyclerView here?:

https://github.com/antoniolg/Kotlin-for-Android-Developers/blob/master/app/src/main/java/com/antonioleiva/weatherapp/activities/MainActivity.kt#L28

Running the code from Chapter 8 branch, the toast never actually occurs. This is the error log I see in Logcat:

11-19 16:57:50.053 5203-5203/? I/zygote: Not late-enabling -Xcheck:jni (already on) 11-19 16:57:50.064 5203-5203/? W/zygote: Unexpected CPU variant for X86 using defaults: x86 11-19 16:57:50.275 5203-5203/com.antonioleiva.weatherapp I/InstantRun: starting instant run server: is main process 11-19 16:57:50.462 5203-5229/com.antonioleiva.weatherapp D/NetworkSecurityConfig: No Network Security Config specified, using platform default 11-19 16:57:50.489 5203-5231/com.antonioleiva.weatherapp D/OpenGLRenderer: HWUI GL Pipeline

                                                                       [ 11-19 16:57:50.541  1902: 2245 W/         ]
                                                                       Unrecognized GLES max version string in extensions: ANDROID_EMU_CHECKSUM_HELPER_v1 ANDROID_EMU_dma_v1 

11-19 16:57:50.545 5203-5229/com.antonioleiva.weatherapp W/System.err: java.io.FileNotFoundException: http://api.openweathermap.org/data/2.5/forecast/daily?APPID=15646a06818f61f7b8d7823ca833e1ce&q=94043&mode=json&units=metric&cnt=7 11-19 16:57:50.546 5203-5229/com.antonioleiva.weatherapp W/System.err: at com.android.okhttp.internal.huc.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:251) 11-19 16:57:50.551 5203-5229/com.antonioleiva.weatherapp W/System.err: at java.net.URL.openStream(URL.java:1058) 11-19 16:57:50.553 5203-5229/com.antonioleiva.weatherapp W/System.err: at kotlin.io.TextStreamsKt.readBytes(ReadWrite.kt:144) 11-19 16:57:50.562 5203-5229/com.antonioleiva.weatherapp W/System.err: at com.antonioleiva.weatherapp.data.Request.run(Request.kt:9) 11-19 16:57:50.563 5203-5229/com.antonioleiva.weatherapp W/System.err: at com.antonioleiva.weatherapp.ui.activities.MainActivity$onCreate$1.invoke(MainActivity.kt:39) 11-19 16:57:50.563 5203-5229/com.antonioleiva.weatherapp W/System.err: at com.antonioleiva.weatherapp.ui.activities.MainActivity$onCreate$1.invoke(MainActivity.kt:15) 11-19 16:57:50.563 5203-5229/com.antonioleiva.weatherapp W/System.err: at org.jetbrains.anko.AsyncKt$doAsync$1.invoke(Async.kt:140) 11-19 16:57:50.569 5203-5229/com.antonioleiva.weatherapp W/System.err: at org.jetbrains.anko.AsyncKt$doAsync$1.invoke(Unknown Source:0) 11-19 16:57:50.570 5203-5229/com.antonioleiva.weatherapp W/System.err: at org.jetbrains.anko.AsyncKt$sam$Callable$761a5578.call(Unknown Source:2) 11-19 16:57:50.570 5203-5229/com.antonioleiva.weatherapp W/System.err: at java.util.concurrent.FutureTask.run(FutureTask.java:266) 11-19 16:57:50.571 5203-5229/com.antonioleiva.weatherapp W/System.err: at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:301) 11-19 16:57:50.572 5203-5229/com.antonioleiva.weatherapp W/System.err: at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162) 11-19 16:57:50.573 5203-5229/com.antonioleiva.weatherapp W/System.err: at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636) 11-19 16:57:50.574 5203-5229/com.antonioleiva.weatherapp W/System.err: at java.lang.Thread.run(Thread.java:764) 11-19 16:57:51.029 5203-5231/com.antonioleiva.weatherapp I/OpenGLRenderer: Initialized EGL, version 1.4 11-19 16:57:51.029 5203-5231/com.antonioleiva.weatherapp D/OpenGLRenderer: Swap behavior 1 11-19 16:57:51.030 5203-5231/com.antonioleiva.weatherapp W/OpenGLRenderer: Failed to choose config with EGL_SWAP_BEHAVIOR_PRESERVED, retrying without... 11-19 16:57:51.030 5203-5231/com.antonioleiva.weatherapp D/OpenGLRenderer: Swap behavior 0 11-19 16:57:51.032 5203-5231/com.antonioleiva.weatherapp D/EGL_emulation: eglCreateContext: 0xa73850c0: maj 2 min 0 rcv 2 11-19 16:57:51.035 5203-5231/com.antonioleiva.weatherapp D/EGL_emulation: eglMakeCurrent: 0xa73850c0: ver 2 0 (tinfo 0xa73832a0)

                                                                      [ 11-19 16:57:51.038  1902: 1911 W/         ]
                                                                      Unrecognized GLES max version string in extensions: ANDROID_EMU_CHECKSUM_HELPER_v1 ANDROID_EMU_dma_v1 

11-19 16:57:51.063 5203-5231/com.antonioleiva.weatherapp D/EGL_emulation: eglMakeCurrent: 0xa73850c0: ver 2 0 (tinfo 0xa73832a0)

importing this demo app in the last canary Android Studio, I found some errors during the sync.

please modify the code of "app" like:

    compile "org.jetbrains.anko:anko:0.10.1"
    compile "org.jetbrains.anko:anko-common:0.10.1"
    compile "org.jetbrains.anko:anko-sqlite:0.10.1n"
    compile "org.jetbrains.anko:anko-coroutines:0.10.1"

this is enounght to fix the errors of sync

regards MaX

Okay. So, I started with the tutorial and everything has been going on fine not until I got to chapter 10 trying to implement the Asyn.

 doAsync {
        val result = RequestForecastCommand("94043").execute()
        Log.e(javaClass.simpleName, result.toString()) <-- It doesn't get to this place at all
        uiThread() {
            Log.e(TAG, "I am here")
            Log.e(javaClass.simpleName, result.toString())
            forcast_list.adapter = ForcastListAdapter(result)
        }
    }

Then, I debugged further and checked the ForecastRequest.kt file

 class ForecastRequest(val zipCode: String) {

companion object {
    private val APP_ID = "15646a06818f61f7b8d7823ca833e1ce"
    private val URL = "http://api.openweathermap.org/data/2.5/" +
            "forecast/daily?mode=json&units=metric&cnt=7"
    private val COMPLETE_URL = "$URL&APPID=$APP_ID&q="
}

fun execute(): ForecastResult {
    val forcastJsonStr = URL(COMPLETE_URL + zipCode).readText()
    Log.e(javaClass.simpleName, forcastJsonStr)<-- This printed out a result
    return Gson().fromJson(forcastJsonStr, ForecastResult::class.java)
}
}

I don't know why it's not throwing any error or any bug though. And should it be a Gson conversion error, at least I'm supposed to get an error right?

I have a doubt about the data classes in ServerClasses.tk. This classes are popullated using GSon. When Gson creates the classes it will use a kind of empty constructor and it will fill the properties, therefore, there might be values that are null (in case the api changes for example). Shouldn't we put default values ensure no null properties?

Hi i see that you use Anko lib, but i recently read that it is a deprecated library:

https://github.com/Kotlin/anko/blob/master/GOODBYE.md

Have you planned to remove this lib and update your code?

https://github.com/antoniolg/Kotlin-for-Android-Developers/blob/c72118e411a9462a37370c1f53a31fc63fe6748b/app/src/main/java/com/antonioleiva/weatherapp/data/db/DbDataMapper.kt#L9

Where does the id come from?