add tag

Author: solygambas

11-blur-o-matic/app/src/main/java/com/example/background/BlurActivity.kt

@@ -20,6 +20,8 @@ import android.os.Bundle
 import android.view.View
 import androidx.activity.viewModels
 import androidx.appcompat.app.AppCompatActivity
+import androidx.lifecycle.Observer
+import androidx.work.WorkInfo
 import com.example.background.databinding.ActivityBlurBinding
 
 class BlurActivity : AppCompatActivity() {
@@ -37,6 +39,8 @@ class BlurActivity : AppCompatActivity() {
         setContentView(binding.root)
 
         binding.goButton.setOnClickListener { viewModel.applyBlur(blurLevel) }
+        // observe work status
+        viewModel.outputWorkInfos.observe(this, workInfosObserver())
     }
 
     /**
@@ -70,4 +74,19 @@ class BlurActivity : AppCompatActivity() {
                 R.id.radio_blur_lv_3 -> 3
                 else -> 1
             }
+
+    // define the observer function
+    private fun workInfosObserver(): Observer<List<WorkInfo>> {
+        return Observer { listOfWorkInfo ->
+            if (listOfWorkInfo.isNullOrEmpty()) {
+                return@Observer
+            }
+            val workInfo = listOfWorkInfo[0]
+            if (workInfo.state.isFinished) {
+                showWorkFinished()
+            } else {
+                showWorkInProgress()
+            }
+        }
+    }
 }

11-blur-o-matic/app/src/main/java/com/example/background/BlurViewModel.kt

@@ -20,13 +20,11 @@ import android.app.Application
 import android.content.ContentResolver
 import android.content.Context
 import android.net.Uri
+import androidx.lifecycle.LiveData
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.ViewModelProvider
-import androidx.work.Data
-import androidx.work.OneTimeWorkRequest
+import androidx.work.*
 //import androidx.work.OneTimeWorkRequest
-import androidx.work.OneTimeWorkRequestBuilder
-import androidx.work.WorkManager
 import com.example.background.workers.BlurWorker
 import com.example.background.workers.CleanupWorker
 import com.example.background.workers.SaveImageToFileWorker
@@ -37,8 +35,12 @@ class BlurViewModel(application: Application) : ViewModel() {
     internal var imageUri: Uri? = null
     internal var outputUri: Uri? = null
 
+    // new instance variable for the workInfo
+    internal val outputWorkInfos: LiveData<List<WorkInfo>>
+
     init {
         imageUri = getImageUri(application.applicationContext)
+        outputWorkInfos = workManager.getWorkInfosByTagLiveData(TAG_OUTPUT)
     }
     /**
      * Create the WorkRequest to apply the blur and save the resulting image
@@ -56,8 +58,16 @@ class BlurViewModel(application: Application) : ViewModel() {
 
         // chain your work
         // add work request to clean up temporary images
+        /*var continuation = workManager
+            .beginWith(OneTimeWorkRequest.from(CleanupWorker::class.java))*/
+        // ensure unique work
         var continuation = workManager
-            .beginWith(OneTimeWorkRequest.from(CleanupWorker::class.java))
+            .beginUniqueWork(
+                IMAGE_MANIPULATION_WORK_NAME,
+                ExistingWorkPolicy.REPLACE,
+                OneTimeWorkRequest.from(CleanupWorker::class.java)
+            )
+
         // add work request to blur the image the number of times requested
         for (i in 0 until blurLevel) {
             val blurBuilder = OneTimeWorkRequestBuilder<BlurWorker>()
@@ -67,7 +77,9 @@ class BlurViewModel(application: Application) : ViewModel() {
             continuation = continuation.then(blurBuilder.build())
         }
         // add work request to save the image to the filesystem
-        val save = OneTimeWorkRequest.Builder(SaveImageToFileWorker::class.java).build()
+        val save = OneTimeWorkRequest.Builder(SaveImageToFileWorker::class.java)
+            .addTag(TAG_OUTPUT)
+            .build()
         continuation = continuation.then(save)
 
         // actually start the work