Add support for heightDp, widthDp, showBackground, backgroundColor

roborazzi-compose-preview-scanner-support/src/main/java/com/github/takahirom/roborazzi/RoborazziPreviewScannerSupport.kt

@@ -14,10 +14,25 @@ fun ComposablePreview<AndroidPreviewInfo>.captureRoboImage(
 ) {
   val composablePreview = this
   composablePreview.applyToRobolectricConfiguration()
-  captureRoboImage(filePath = filePath, roborazziOptions = roborazziOptions) {
-    composablePreview()
-  }
+  captureRoboImageWithActivityScenarioSetup(
+    filePath = filePath,
+    roborazziOptions = roborazziOptions,
+    content = { activityScenario ->
+
+      activityScenario.setBackgroundColor(
+        showBackground = composablePreview.previewInfo.showBackground,
+        backgroundColor = composablePreview.previewInfo.backgroundColor
+      )
+
+      activityScenario.createSizedPreview(
+        widthDp = composablePreview.previewInfo.widthDp,
+        heightDp = composablePreview.previewInfo.heightDp,
+        preview = { composablePreview() }
+      )
+    },
+  )
 }
+
 /**
  * ComposePreviewTester is an interface that allows you to define a custom test for a Composable preview.
  * The class that implements this interface should have a parameterless constructor.

roborazzi-compose/build.gradle

@@ -17,6 +17,7 @@ dependencies {
 
   testImplementation libs.androidx.compose.runtime
   compileOnly libs.androidx.compose.ui
+  compileOnly libs.androidx.compose.foundation
   compileOnly libs.androidx.activity.compose
   compileOnly libs.robolectric
 }

roborazzi-compose/src/main/java/com/github/takahirom/roborazzi/ActivityScenarioExtensions.kt

@@ -0,0 +1,95 @@
+package com.github.takahirom.roborazzi
+
+import android.app.Activity
+import android.graphics.Color
+import androidx.compose.foundation.layout.Box
+import androidx.compose.foundation.layout.height
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import androidx.test.core.app.ActivityScenario
+import org.robolectric.Shadows.shadowOf
+import org.robolectric.shadows.ShadowDisplay.getDefaultDisplay
+import kotlin.math.roundToInt
+
+fun ActivityScenario<out Activity>.setBackgroundColor(
+  showBackground: Boolean,
+  backgroundColor: Long,
+) {
+  when (showBackground) {
+    false -> {
+      onActivity { activity ->
+        activity.window.decorView.setBackgroundColor(Color.TRANSPARENT)
+      }
+    }
+
+    true -> {
+      val color = when (backgroundColor != 0L) {
+        true -> backgroundColor.toInt()
+        false -> Color.WHITE
+      }
+      onActivity { activity ->
+        activity.window.decorView.setBackgroundColor(color)
+      }
+    }
+  }
+}
+
+fun ActivityScenario<out Activity>.createSizedPreview(
+  widthDp: Int,
+  heightDp: Int,
+  preview: @Composable () -> Unit
+): @Composable () -> Unit {
+  var result: (@Composable () -> Unit)? = null
+  onActivity { activity ->
+    activity.setDisplaySize(widthDp = widthDp, heightDp = heightDp)
+    result = preview.size(widthDp = widthDp, heightDp = heightDp)
+  }
+  return result
+    ?: throw IllegalStateException("The preview could not be sucessfully sized to widthDp = $widthDp and heightDp = $heightDp")
+}
+
+
+internal fun Activity.setDisplaySize(
+  widthDp: Int,
+  heightDp: Int
+) {
+  if (widthDp <= 0 && heightDp <= 0) return
+
+  val display = shadowOf(getDefaultDisplay())
+  val density = resources.displayMetrics.density
+  if (widthDp > 0) {
+    val widthPx = (widthDp * density).roundToInt()
+    display.setWidth(widthPx)
+  }
+  if (heightDp > 0) {
+    val heightPx = (heightDp * density).roundToInt()
+    display.setHeight(heightPx)
+  }
+  recreate()
+}
+
+/**
+ * WARNING:
+ * For this to work, it requires that the Display is within the widthDp and heightDp dimensions
+ * You can ensure that by calling [Activity.setDisplaySize] before
+ */
+internal fun (@Composable () -> Unit).size(
+  widthDp: Int,
+  heightDp: Int,
+): @Composable () -> Unit {
+  val resizedPreview = @Composable {
+    val modifier = when {
+      widthDp > 0 && heightDp > 0 -> Modifier.size(widthDp.dp, heightDp.dp)
+      widthDp > 0 -> Modifier.width(widthDp.dp)
+      heightDp > 0 -> Modifier.height(heightDp.dp)
+      else -> Modifier
+    }
+    Box(modifier = modifier) {
+      this@size()
+    }
+  }
+  return resizedPreview
+}

roborazzi-compose/src/main/java/com/github/takahirom/roborazzi/RegisterActivityToRobolectric.kt

@@ -0,0 +1,24 @@
+package com.github.takahirom.roborazzi
+
+import android.app.Application
+import android.content.ComponentName
+import androidx.test.core.app.ApplicationProvider
+import org.robolectric.Shadows
+
+/**
+ * Workaround for https://github.com/takahirom/roborazzi/issues/100
+ */
+internal fun registerActivityToRobolectricIfNeeded() {
+  try {
+    val appContext: Application = ApplicationProvider.getApplicationContext()
+    Shadows.shadowOf(appContext.packageManager).addActivityIfNotPresent(
+      ComponentName(
+        appContext.packageName,
+        RoborazziTransparentActivity::class.java.name,
+      )
+    )
+  } catch (e: ClassNotFoundException) {
+    // Configured to run even without Robolectric
+    e.printStackTrace()
+  }
+}

roborazzi-compose/src/main/java/com/github/takahirom/roborazzi/RoborazziCompose.kt

@@ -1,15 +1,13 @@
 package com.github.takahirom.roborazzi
 
-import android.app.Application
-import android.content.ComponentName
+import android.app.Activity
 import android.view.ViewGroup
+import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
 import androidx.compose.runtime.Composable
 import androidx.compose.ui.platform.ComposeView
 import androidx.compose.ui.platform.ViewRootForTest
 import androidx.test.core.app.ActivityScenario
-import androidx.test.core.app.ApplicationProvider
-import org.robolectric.Shadows
 import java.io.File
 
 fun captureRoboImage(
@@ -30,16 +28,12 @@ fun captureRoboImage(
   content: @Composable () -> Unit,
 ) {
   if (!roborazziOptions.taskType.isEnabled()) return
-  registerRoborazziActivityToRobolectricIfNeeded()
+  registerActivityToRobolectricIfNeeded()
+
   val activityScenario = ActivityScenario.launch(RoborazziTransparentActivity::class.java)
   activityScenario.use {
-    activityScenario.onActivity { activity ->
-      activity.setContent(content = content)
-      val composeView = activity.window.decorView
-        .findViewById<ViewGroup>(android.R.id.content)
-        .getChildAt(0) as ComposeView
-      val viewRootForTest = composeView.getChildAt(0) as ViewRootForTest
-      viewRootForTest.view.captureRoboImage(file, roborazziOptions)
+    activityScenario.captureRoboImage(file, roborazziOptions){
+      content()
     }
 
     // Closing the activity is necessary to prevent memory leaks.
@@ -48,20 +42,55 @@ fun captureRoboImage(
   }
 }
 
-/**
- * Workaround for https://github.com/takahirom/roborazzi/issues/100
- */
-private fun registerRoborazziActivityToRobolectricIfNeeded() {
-  try {
-    val appContext: Application = ApplicationProvider.getApplicationContext()
-    Shadows.shadowOf(appContext.packageManager).addActivityIfNotPresent(
-      ComponentName(
-        appContext.packageName,
-        RoborazziTransparentActivity::class.java.name,
-      )
-    )
-  } catch (e: ClassNotFoundException) {
-    // Configured to run even without Robolectric
-    e.printStackTrace()
+fun captureRoboImageWithActivityScenarioSetup(
+  filePath: String,
+  roborazziOptions: RoborazziOptions = provideRoborazziContext().options,
+  content: (ActivityScenario<out Activity>) -> @Composable () -> Unit,
+) {
+  if (!roborazziOptions.taskType.isEnabled()) return
+  registerActivityToRobolectricIfNeeded()
+
+  val activityScenario = ActivityScenario.launch(RoborazziTransparentActivity::class.java)
+
+  activityScenario.use {
+    val sizedPreview = content(activityScenario)
+    activityScenario.captureRoboImage(filePath, roborazziOptions){
+      sizedPreview()
+    }
+
+    // Closing the activity is necessary to prevent memory leaks.
+    // If multiple captureRoboImage calls occur in a single test,
+    // they can lead to an activity leak.
   }
 }
+
+
+private fun ActivityScenario<out ComponentActivity>.captureRoboImage(
+  filePath: String,
+  roborazziOptions: RoborazziOptions = provideRoborazziContext().options,
+  content: @Composable () -> Unit,
+) {
+  captureRoboImage(
+    file = fileWithRecordFilePathStrategy(filePath),
+    roborazziOptions = roborazziOptions,
+    content = content
+  )
+}
+
+private fun ActivityScenario<out ComponentActivity>.captureRoboImage(
+  file: File,
+  roborazziOptions: RoborazziOptions = provideRoborazziContext().options,
+  content: @Composable () -> Unit,
+) {
+
+  onActivity { activity ->
+    activity.setContent(content = { content() })
+
+    val composeView = activity.window.decorView
+      .findViewById<ViewGroup>(android.R.id.content)
+      .getChildAt(0) as ComposeView
+
+    val viewRootForTest = composeView.getChildAt(0) as ViewRootForTest
+    viewRootForTest.view.captureRoboImage(file, roborazziOptions)
+  }
+}

roborazzi/src/main/java/com/github/takahirom/roborazzi/RoborazziTransparentActivity.kt

@@ -1,11 +1,11 @@
 package com.github.takahirom.roborazzi
 
 import android.os.Bundle
-import android.os.PersistableBundle
 import androidx.activity.ComponentActivity
 
 class RoborazziTransparentActivity: ComponentActivity() {
-  override fun onCreate(savedInstanceState: Bundle?, persistentState: PersistableBundle?) {
-    super.onCreate(savedInstanceState, persistentState)
+  override fun onCreate(savedInstanceState: Bundle?) {
+    setTheme(android.R.style.Theme_Translucent_NoTitleBar_Fullscreen)
+    super.onCreate(savedInstanceState)
   }
 }

roborazzi/src/main/res/values/themes.xml

@@ -1,6 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 <resources xmlns:tools="http://schemas.android.com/tools">
   <!-- Base application theme. -->
+  <!-- It seems that this theme isn't used because of test resource merger issue -->
   <style name="RoborazziTransparentTheme">
     <item name="android:colorBackground">@android:color/transparent</item>
     <item name="android:windowActionBar">false</item>

sample-generate-preview-tests/build.gradle.kts

@@ -47,6 +47,8 @@ android {
       isIncludeAndroidResources = true
       all {
         it.systemProperties["robolectric.pixelCopyRenderMode"] = "hardware"
+        // For large preview
+        it.maxHeapSize = "4096m"
       }
     }
   }