Merge pull request #826 from vector-im/feature/bma/swipeAction

Improve swipe to reply rendering

libraries/designsystem/src/main/kotlin/io/element/android/libraries/designsystem/swipe/SwipeableActionsState.kt

@@ -0,0 +1,75 @@
+/*
+ * Copyright (c) 2023 New Vector Ltd
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.element.android.libraries.designsystem.swipe
+
+import androidx.compose.animation.core.Animatable
+import androidx.compose.animation.core.tween
+import androidx.compose.foundation.MutatePriority
+import androidx.compose.foundation.gestures.DraggableState
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.Stable
+import androidx.compose.runtime.State
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
+
+/**
+ * Inspired from https://github.com/bmarty/swipe/blob/trunk/swipe/src/main/kotlin/me/saket/swipe/SwipeableActionsState.kt
+ */
+@Composable
+fun rememberSwipeableActionsState(): SwipeableActionsState {
+    return remember { SwipeableActionsState() }
+}
+
+@Stable
+class SwipeableActionsState {
+    /**
+     * The current position (in pixels) of the content.
+     */
+    val offset: State<Float> get() = offsetState
+    private var offsetState = mutableStateOf(0f)
+
+    /**
+     * Whether the content is currently animating to reset its offset after it was swiped.
+     */
+    var isResettingOnRelease: Boolean by mutableStateOf(false)
+        private set
+
+    val draggableState = DraggableState { delta ->
+        val targetOffset = offsetState.value + delta
+        val isAllowed = isResettingOnRelease || targetOffset > 0f
+
+        offsetState.value += if (isAllowed) delta else 0f
+    }
+
+    suspend fun resetOffset() {
+        draggableState.drag(MutatePriority.PreventUserInput) {
+            isResettingOnRelease = true
+            try {
+                Animatable(offsetState.value).animateTo(
+                    targetValue = 0f,
+                    animationSpec = tween(durationMillis = 300),
+                ) {
+                    dragBy(value - offsetState.value)
+                }
+            } finally {
+                isResettingOnRelease = false
+            }
+        }
+    }
+}