Add generic Compose fragment.

app/src/main/java/org/thoughtcrime/securesms/compose/ComposeFragment.kt

@@ -0,0 +1,34 @@
+package org.thoughtcrime.securesms.compose
+
+import android.os.Bundle
+import android.view.LayoutInflater
+import android.view.View
+import android.view.ViewGroup
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.platform.ComposeView
+import androidx.compose.ui.platform.LocalContext
+import androidx.compose.ui.platform.ViewCompositionStrategy
+import org.signal.core.ui.theme.SignalTheme
+import org.thoughtcrime.securesms.LoggingFragment
+import org.thoughtcrime.securesms.util.DynamicTheme
+
+/**
+ * Generic ComposeFragment which can be subclassed to build UI with compose.
+ */
+abstract class ComposeFragment : LoggingFragment() {
+  override fun onCreateView(inflater: LayoutInflater, container: ViewGroup?, savedInstanceState: Bundle?): View? {
+    return ComposeView(requireContext()).apply {
+      setViewCompositionStrategy(ViewCompositionStrategy.DisposeOnViewTreeLifecycleDestroyed)
+      setContent {
+        SignalTheme(
+          isDarkMode = DynamicTheme.isDarkTheme(LocalContext.current)
+        ) {
+          SheetContent()
+        }
+      }
+    }
+  }
+
+  @Composable
+  abstract fun SheetContent()
+}