Fix opening files from external apps

I somehow missed this when migrating to compose and worse yet, didn't have any tests covering it. That's been remedied now so hopefully it continues to work well into the future

Closes #90

app/src/androidTest/kotlin/com/wbrawner/simplemarkdown/MarkdownTests.kt

@@ -182,6 +182,29 @@ class MarkdownTests {
         }
     }
 
+    @Test
+    fun launchWithContentUriTest() = runTest {
+        val markdownText = "# UI Testing\n\nThe quick brown fox jumped over the lazy dog."
+        file.outputStream().writer().use { it.write(markdownText) }
+        val fileUri = FileProvider.getUriForFile(
+            getApplicationContext(),
+            "${BuildConfig.APPLICATION_ID}.fileprovider",
+            file
+        )
+        ActivityScenario.launch<MainActivity>(
+            Intent(
+                Intent.ACTION_VIEW,
+                fileUri,
+                getInstrumentation().targetContext,
+                MainActivity::class.java
+            )
+        )
+        onMainScreen(composeRule) {
+            awaitIdle()
+            checkMarkdownEquals(markdownText)
+            checkTitleEquals("temp.md")
+        }
+    }
 
     @Test
     fun openEditAndSaveMarkdownTest() = runTest {

app/src/main/java/com/wbrawner/simplemarkdown/MarkdownViewModel.kt

@@ -14,7 +14,6 @@ import kotlinx.coroutines.flow.MutableStateFlow
 import kotlinx.coroutines.flow.asStateFlow
 import kotlinx.coroutines.flow.launchIn
 import kotlinx.coroutines.flow.onEach
-import kotlinx.coroutines.launch
 import kotlinx.coroutines.sync.Mutex
 import kotlinx.coroutines.sync.withLock
 import kotlinx.coroutines.withContext
@@ -50,9 +49,6 @@ class MarkdownViewModel(
     private val saveMutex = Mutex()
 
     init {
-        viewModelScope.launch {
-            load(null)
-        }
         preferenceHelper.observe<Boolean>(Preference.LOCK_SWIPING)
             .onEach {
                 _state.value = _state.value.copy(lockSwiping = it)

app/src/main/java/com/wbrawner/simplemarkdown/ui/MainScreen.kt

@@ -61,6 +61,7 @@ import com.wbrawner.simplemarkdown.MarkdownViewModel
 import com.wbrawner.simplemarkdown.ParameterizedText
 import com.wbrawner.simplemarkdown.R
 import com.wbrawner.simplemarkdown.Route
+import com.wbrawner.simplemarkdown.utility.activity
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.flow.distinctUntilChanged
 import kotlinx.coroutines.flow.map
@@ -86,6 +87,10 @@ fun MainScreen(
     val alert by viewModel.collectAsState(EditorState::alert, null)
     val saveCallback by viewModel.collectAsState(EditorState::saveCallback, null)
     val lockSwiping by viewModel.collectAsState(EditorState::lockSwiping, false)
+    val intentData = LocalContext.current.activity?.intent?.data
+    LaunchedEffect(intentData) {
+        viewModel.load(intentData?.toString())
+    }
     LaunchedEffect(enableAutosave) {
         if (!enableAutosave) return@LaunchedEffect
         while (isActive) {

app/src/main/java/com/wbrawner/simplemarkdown/utility/Extensions.kt

@@ -1,11 +1,11 @@
 package com.wbrawner.simplemarkdown.utility
 
+import android.app.Activity
 import android.content.Context
+import android.content.ContextWrapper
 import android.content.res.AssetManager
 import android.net.Uri
 import android.provider.OpenableColumns
-import android.view.View
-import android.view.inputmethod.InputMethodManager
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
 import java.io.Reader
@@ -41,3 +41,11 @@ suspend fun Uri.getName(context: Context): String {
     }
     return fileName ?: "Untitled.md"
 }
+
+@Suppress("RecursivePropertyAccessor")
+val Context.activity: Activity?
+    get() = when (this) {
+        is Activity -> this
+        is ContextWrapper -> baseContext.activity
+        else -> null
+    }