Adds download progress for flexible updates

Refs: #23

Author: Nikolay Kochetkov

README.md

@@ -166,6 +166,15 @@ fun updateFailed(e: Throwable)
 Effective within the `IMMEDIATE` update flow to report a critical update error. Within the immediate update flow this is
 considered critical and you may want to terminate application.
 
+#### updateDownloadProgress (optional)
+```kotlin
+fun updateDownloadProgress(bytesLoaded: Long, bytesTotal: Long)
+```
+Called in flexible flow to report that update download progress. You may display a progress bar or something.
+
+ - bytesLoaded - number of bytes downloaded
+ - bytesTotal - total number of bytes to download
+
 #### updateChecking (optional)
 ```kotlin
 fun updateChecking()

appupdatewrapper/src/main/java/com/motorro/appupdatewrapper/AppUpdateView.kt

@@ -55,6 +55,13 @@ interface AppUpdateView {
      */
     fun updateDownloadStarts() = Unit
 
+    /**
+     * Called when update download progress changes
+     * @param bytesLoaded Bytes loaded
+     * @param bytesTotal Total bytes to load
+     */
+    fun updateDownloadProgress(bytesLoaded: Long, bytesTotal: Long) = Unit
+
     /**
      * Reports update is downloaded and ready to be installed
      * When ready to proceed call [AppUpdateState.userConfirmedUpdate]

appupdatewrapper/src/main/java/com/motorro/appupdatewrapper/FlexibleUpdateState.kt

@@ -295,6 +295,12 @@ internal sealed class FlexibleUpdateState : AppUpdateState(), Tagged {
                     markUserCancelTime()
                     complete()
                 }
+                DOWNLOADING -> withUpdateView {
+                    updateDownloadProgress(
+                        state.bytesDownloaded(),
+                        state.totalBytesToDownload()
+                    )
+                }
                 DOWNLOADED -> installConsent()
                 INSTALLING -> completeUpdate()
                 FAILED -> {

appupdatewrapper/src/test/java/com/motorro/appupdatewrapper/FlexibleUpdateStateTest.kt

@@ -24,7 +24,15 @@ import com.google.android.play.core.install.model.ActivityResult
 import com.google.android.play.core.install.model.AppUpdateType.FLEXIBLE
 import com.google.android.play.core.install.model.InstallStatus
 import com.google.android.play.core.install.model.UpdateAvailability
-import com.nhaarman.mockitokotlin2.*
+import com.nhaarman.mockitokotlin2.any
+import com.nhaarman.mockitokotlin2.argumentCaptor
+import com.nhaarman.mockitokotlin2.check
+import com.nhaarman.mockitokotlin2.doReturn
+import com.nhaarman.mockitokotlin2.mock
+import com.nhaarman.mockitokotlin2.never
+import com.nhaarman.mockitokotlin2.times
+import com.nhaarman.mockitokotlin2.verify
+import com.nhaarman.mockitokotlin2.whenever
 import org.junit.Test
 import org.junit.runner.RunWith
 import org.robolectric.Shadows.shadowOf
@@ -261,6 +269,27 @@ internal class FlexibleUpdateStateTest: BaseAppUpdateStateTest() {
         shadowOf(getMainLooper()).idle()
     }
 
+    @Test
+    @LooperMode(LooperMode.Mode.PAUSED)
+    fun downloadingStateWillUpdateProgress() {
+        updateManager.setUpdateAvailable(100500)
+        updateManager.withInfo {
+            startUpdateFlowForResult(it, FLEXIBLE, activity, 100)
+            assertTrue(isConfirmationDialogVisible)
+            userAcceptsUpdate()
+            downloadStarts()
+            setTotalBytesToDownload(100)
+
+            val state = FlexibleUpdateState.Downloading().init()
+            state.onResume()
+            shadowOf(getMainLooper()).idle()
+
+            setBytesDownloaded(50)
+            verify(view).updateDownloadProgress(50, 100)
+        }
+        shadowOf(getMainLooper()).idle()
+    }
+
     @Test
     @LooperMode(LooperMode.Mode.PAUSED)
     fun downloadingStateWillSetInstallConsentWhenDownloaded() {