Adding pip snippets to latest branch

compose/snippets/src/main/java/com/example/compose/snippets/pictureinpicture/PictureInPictureSnippets.kt

@@ -0,0 +1,75 @@
+package com.example.compose.snippets.pictureinpicture
+
+import android.app.PictureInPictureParams
+import android.content.Context
+import android.content.ContextWrapper
+import android.os.Build
+import androidx.activity.ComponentActivity
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.DisposableEffect
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.rememberUpdatedState
+import androidx.compose.ui.platform.LocalContext
+
+@Composable
+fun PipListenerPreAPI12(shouldEnterPipMode: Boolean) {
+    // [START android_compose_pip_pre12_listener]
+    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O &&
+        Build.VERSION.SDK_INT < Build.VERSION_CODES.S
+    ) {
+        val context = LocalContext.current
+        DisposableEffect(context) {
+            val onUserLeaveBehavior : () -> Unit = {
+                context.findActivity()
+                    .enterPictureInPictureMode(PictureInPictureParams.Builder().build())
+            }
+            context.findActivity().addOnUserLeaveHintListener(
+                onUserLeaveBehavior
+            )
+            onDispose {
+                context.findActivity().removeOnUserLeaveHintListener(
+                    onUserLeaveBehavior
+                )
+            }
+        }
+    }
+    // [END android_compose_pip_pre12_listener]
+}
+
+@Composable
+fun EnterPiPPre12(shouldEnterPipMode: Boolean) {
+    // [START android_compose_pip_pre12_should_enter_pip]
+    val currentShouldEnterPipMode by rememberUpdatedState(newValue = shouldEnterPipMode)
+    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O &&
+        Build.VERSION.SDK_INT < Build.VERSION_CODES.S
+    ) {
+        val context = LocalContext.current
+        DisposableEffect(context) {
+            val onUserLeaveBehavior: () -> Unit= {
+                if (currentShouldEnterPipMode) {
+                    context.findActivity()
+                        .enterPictureInPictureMode(PictureInPictureParams.Builder().build())
+                }
+            }
+            context.findActivity().addOnUserLeaveHintListener(
+                onUserLeaveBehavior
+            )
+            onDispose {
+                context.findActivity().removeOnUserLeaveHintListener(
+                    onUserLeaveBehavior
+                )
+            }
+        }
+    }
+    // [END android_compose_pip_pre12_should_enter_pip]
+}
+
+internal fun Context.findActivity(): ComponentActivity {
+    var context = this
+    while (context is ContextWrapper) {
+        if (context is ComponentActivity) return context
+        context = context.baseContext
+    }
+    throw IllegalStateException("Picture in picture should be called in the context of an Activity")
+}
+