Merge pull request #23 from polytypic/fix/make-startWith-callable-fro…

…m-any-thread Fix: Make startWith callable from any thread
adibfara · Apr 24, 2020 · 571e317 · 571e317
2 parents b30c647 + b5fcaf5
commit 571e317
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Showing 2 changed files with 15 additions and 5 deletions.
diff --git a/lives/src/main/java/com/snakydesign/livedataextensions/Combining.kt b/lives/src/main/java/com/snakydesign/livedataextensions/Combining.kt
@@ -9,6 +9,7 @@ package com.snakydesign.livedataextensions
 
 import androidx.lifecycle.LiveData
 import androidx.lifecycle.MediatorLiveData
+import androidx.lifecycle.MutableLiveData
 import com.snakydesign.livedataextensions.livedata.SingleLiveData
 import com.snakydesign.livedataextensions.operators.SingleLiveDataConcat
 import java.util.concurrent.atomic.AtomicBoolean
@@ -46,10 +47,19 @@ fun <T> merge(liveDataList: List<LiveData<T>>): LiveData<T> {
  * Emits the `startingValue` before any other value.
  */
 fun <T> LiveData<T>.startWith(startingValue: T?): LiveData<T> {
- val finalLiveData: MediatorLiveData<T> = MediatorLiveData()
- finalLiveData.value = startingValue
- finalLiveData.addSource(this) { source ->
- finalLiveData.value = source
+ val finalLiveData = MediatorLiveData<T>()
+ var startingData: LiveData<T>? = MutableLiveData(startingValue)
+ finalLiveData.addSource(this) {
+ if (null != startingData) {
+ finalLiveData.removeSource(startingData!!)
+ startingData = null
+ }
+ finalLiveData.value = it
+ }
+ finalLiveData.addSource(startingData!!) {
+ finalLiveData.value = it
+ finalLiveData.removeSource(startingData!!)
+ startingData = null
  }
  return finalLiveData
 }

diff --git a/versions.gradle b/versions.gradle
@@ -6,7 +6,7 @@ ext.versionNumbers = [
 
  kotlin : '1.3.20',
  mockito : '2.21.0',
- arch : '2.0.0',
+ arch : '2.1.0',
  junit : '4.12',
 
  minSdk : 16,