feat: support for predictive back gestures

Author: Bnyro

app/src/main/AndroidManifest.xml

@@ -53,7 +53,8 @@
         android:label="@string/app_name"
         android:supportsRtl="true"
         android:theme="@style/Theme.ConnectYou"
-        tools:targetApi="33">
+        tools:targetApi="33"
+        android:enableOnBackInvokedCallback="true">
 
         <activity
             android:name=".ui.activities.MainActivity"

app/src/main/java/com/bnyro/contacts/presentation/components/FullscreenDialog.kt

@@ -1,33 +1,57 @@
 package com.bnyro.contacts.presentation.components
 
+import androidx.activity.compose.PredictiveBackHandler
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.material3.Surface
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.LaunchedEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableFloatStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.ExperimentalComposeUiApi
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.alpha
 import androidx.compose.ui.platform.LocalView
 import androidx.compose.ui.window.Dialog
 import androidx.compose.ui.window.DialogProperties
 import androidx.compose.ui.window.DialogWindowProvider
+import kotlinx.coroutines.CancellationException
 
 @OptIn(ExperimentalComposeUiApi::class)
 @Composable
 fun FullScreenDialog(onClose: () -> Unit, content: @Composable () -> Unit) {
+    var alpha by remember {
+        mutableFloatStateOf(1f)
+    }
+
     Dialog(
         properties = DialogProperties(
             usePlatformDefaultWidth = false,
             decorFitsSystemWindows = false
         ),
         onDismissRequest = onClose
     ) {
+        PredictiveBackHandler { progress ->
+            try {
+                progress.collect { p ->
+                    alpha = 1 - 1.3f * p.progress
+                }
+                onClose()
+            } catch (_: CancellationException) {
+                alpha = 1f
+            }
+        }
+
         val dialogWindowProvider = LocalView.current.parent as DialogWindowProvider
         LaunchedEffect(dialogWindowProvider) {
             dialogWindowProvider.window.setDimAmount(0f)
         }
 
         Surface(
-            modifier = Modifier.fillMaxSize()
+            modifier = Modifier
+                .fillMaxSize()
+                .alpha(alpha)
         ) {
             content.invoke()
         }