Merge pull request #9 from Mr-Pine/development

Merge for Version 1.1.2

Author: Mr-Pine

zoomables/build.gradle

@@ -57,7 +57,7 @@ dependencies {
 
 ext{
     PUBLISH_GROUP_ID = 'de.mr-pine.utils'
-    PUBLISH_VERSION = '1.1.1'
+    PUBLISH_VERSION = '1.1.2'
     PUBLISH_ARTIFACT_ID = 'zoomables'
 }
 

zoomables/src/main/kotlin/de/mr_pine/zoomables/ZoomableImage.kt

@@ -23,6 +23,7 @@ import kotlinx.coroutines.CoroutineScope
  * @param contentDescription text for accessibility see [Image] for further info
  * @param onSwipeLeft Optional function to run when user swipes from right to left - does nothing by default
  * @param onSwipeRight Optional function to run when user swipes from left to right - does nothing by default
+ * @param dragGesturesEnabled A function with a [ZoomableState] scope that returns a boolean value to enable/disable dragging gestures (swiping and panning). Returns `true` by default. *Note*: For some use cases it may be required that only panning is possible. Use `{!notTransformed}` in that case
  * @param onDoubleTap Optional function to run when user double taps. Zooms in by 2x when scale is currently 1 and zooms out to scale = 1 when zoomed in when null (default)
  */
 @Composable
@@ -34,13 +35,15 @@ public fun ZoomableImage(
     contentDescription: String? = null,
     onSwipeLeft: () -> Unit = {},
     onSwipeRight: () -> Unit = {},
+    dragGesturesEnabled: ZoomableState.() -> Boolean = { true },
     onDoubleTap: ((Offset) -> Unit)? = null
 ) {
     Zoomable(
         coroutineScope = coroutineScope,
         zoomableState = zoomableState,
         onSwipeLeft = onSwipeLeft,
         onSwipeRight = onSwipeRight,
+        dragGesturesEnabled = dragGesturesEnabled,
         onDoubleTap = onDoubleTap
     ) {
         Image(bitmap = bitmap, contentDescription = contentDescription, modifier = modifier)
@@ -57,6 +60,7 @@ public fun ZoomableImage(
  * @param contentDescription text for accessibility see [Image] for further info
  * @param onSwipeLeft Optional function to run when user swipes from right to left - does nothing by default
  * @param onSwipeRight Optional function to run when user swipes from left to right - does nothing by default
+ * @param dragGesturesEnabled A function with a [ZoomableState] scope that returns a boolean value to enable/disable dragging gestures (swiping and panning). Returns `true` by default. *Note*: For some use cases it may be required that only panning is possible. Use `{!notTransformed}` in that case
  * @param onDoubleTap Optional function to run when user double taps. Zooms in by 2x when scale is currently 1 and zooms out to scale = 1 when zoomed in when null (default)
  */
 @Composable
@@ -68,13 +72,15 @@ public fun ZoomableImage(
     contentDescription: String? = null,
     onSwipeLeft: () -> Unit = {},
     onSwipeRight: () -> Unit = {},
+    dragGesturesEnabled: ZoomableState.() -> Boolean = { true },
     onDoubleTap: ((Offset) -> Unit)? = null
 ) {
     Zoomable(
         coroutineScope = coroutineScope,
         zoomableState = zoomableState,
         onSwipeLeft = onSwipeLeft,
         onSwipeRight = onSwipeRight,
+        dragGesturesEnabled = dragGesturesEnabled,
         onDoubleTap = onDoubleTap
     ) {
         Image(
@@ -95,6 +101,7 @@ public fun ZoomableImage(
  * @param contentDescription text for accessibility see [Image] for further info
  * @param onSwipeLeft Optional function to run when user swipes from right to left - does nothing by default
  * @param onSwipeRight Optional function to run when user swipes from left to right - does nothing by default
+ * @param dragGesturesEnabled A function with a [ZoomableState] scope that returns a boolean value to enable/disable dragging gestures (swiping and panning). Returns `true` by default. *Note*: For some use cases it may be required that only panning is possible. Use `{!notTransformed}` in that case
  * @param onDoubleTap Optional function to run when user double taps. Zooms in by 2x when scale is currently 1 and zooms out to scale = 1 when zoomed in when null (default)
  */
 @Composable
@@ -106,13 +113,15 @@ public fun ZoomableImage(
     contentDescription: String? = null,
     onSwipeLeft: () -> Unit = {},
     onSwipeRight: () -> Unit = {},
+    dragGesturesEnabled: ZoomableState.() -> Boolean = { true },
     onDoubleTap: ((Offset) -> Unit)? = null
 ) {
     Zoomable(
         coroutineScope = coroutineScope,
         zoomableState = zoomableState,
         onSwipeLeft = onSwipeLeft,
         onSwipeRight = onSwipeRight,
+        dragGesturesEnabled = dragGesturesEnabled,
         onDoubleTap = onDoubleTap
     ) {
         Image(painter = painter, contentDescription = contentDescription, modifier = modifier)

zoomables/src/main/kotlin/de/mr_pine/zoomables/ZoomableState.kt

@@ -28,12 +28,12 @@ import kotlin.math.sqrt
  *
  * @param onTransformation callback invoked when transformation occurs. The callback receives the
  * change from the previous event. It's relative scale multiplier for zoom, [Offset] in pixels
- * for pan and degrees for rotation. If this parameter is null the default behaviour is
- * zooming, panning and rotating by the supplied changes. Rotation is kept between positive and negative 180
+ * for pan and degrees for rotation.
  *
  * @property scale The current scale as [MutableState]<[Float]>
  * @property offset The current offset as [MutableState]<[Offset]>
  * @property rotation The current rotation in degrees as [MutableState]<[Float]>
+ * @property notTransformed `true` if [scale] is `1`, [offset] is [Offset.Zero] and [rotation] is `0`
  */
 public class ZoomableState(
     public var scale: MutableState<Float>,
@@ -42,6 +42,12 @@ public class ZoomableState(
     public val rotationBehavior: Rotation,
     onTransformation: ZoomableState.(zoomChange: Float, panChange: Offset, rotationChange: Float) -> Unit
 ) : TransformableState {
+
+    public val notTransformed: Boolean
+        get() {
+            return scale.value in (1 - 1.0E-3f)..(1 + 1.0E-3f) && offset.value.getDistanceSquared()  in -1.0E-6f..1.0E-6f && rotation.value in -1.0E-3f..1.0E-3f
+        }
+
     private val transformScope: TransformScope = object : TransformScope {
         override fun transformBy(zoomChange: Float, panChange: Offset, rotationChange: Float) =
             onTransformation(zoomChange, panChange, rotationChange)
@@ -51,6 +57,7 @@ public class ZoomableState(
 
     private val isTransformingState = mutableStateOf(false)
 
+
     override suspend fun transform(
         transformPriority: MutatePriority,
         block: suspend TransformScope.() -> Unit
@@ -87,7 +94,11 @@ public class ZoomableState(
         }
     }
 
-    public suspend fun animateZoomToPosition(zoomChange: Float, position: Offset, currentComposableCenter: Offset = Offset.Zero) {
+    public suspend fun animateZoomToPosition(
+        zoomChange: Float,
+        position: Offset,
+        currentComposableCenter: Offset = Offset.Zero
+    ) {
         val offsetBuffer = offset.value
 
         val x0 = position.x - currentComposableCenter.x
@@ -143,7 +154,7 @@ public class ZoomableState(
  *
  * @param onTransformation callback invoked when transformation occurs. The callback receives the
  * change from the previous event. It's relative scale multiplier for zoom, [Offset] in pixels
- * for pan and degrees for rotation. If this parameter is null the default behaviour is
+ * for pan and degrees for rotation. If not provided the default behaviour is
  * zooming, panning and rotating by the supplied changes. Rotation is kept between positive and negative 180
  *
  * @return A [ZoomableState] initialized with the given [initialZoom], [initialOffset] and [initialRotation]

zoomables/src/main/kotlin/de/mr_pine/zoomables/Zoomables.kt

@@ -34,16 +34,18 @@ import kotlin.math.*
  *
  * @param coroutineScope used for smooth asynchronous zoom/pan/rotation animations
  * @param zoomableState Contains the current transform states - obtained via [rememberZoomableState]
+ * @param dragGesturesEnabled A function with a [ZoomableState] scope that returns a boolean value to enable/disable dragging gestures (swiping and panning). Returns `true` by default. *Note*: For some use cases it may be required that only panning is possible. Use `{!notTransformed}` in that case
  * @param onSwipeLeft Optional function to run when user swipes from right to left - does nothing by default
  * @param onSwipeRight Optional function to run when user swipes from left to right - does nothing by default
  * @param minimumSwipeDistance Minimum distance the user has to travel on the screen for it to count as swiping
- * @param onDoubleTap Optional function to run when user double taps. Zooms in by 2x to the touch point when scale is currently 1 and zooms out to scale = 1 when zoomed in when null (default)
+ * @param onDoubleTap Optional function to run when user double taps. Zooms in by 2x to the touch point when scale is currently 1 and zooms out to scale = 1 when zoomed in when `null` (default)
  */
 
 @Composable
 public fun Zoomable(
     coroutineScope: CoroutineScope,
     zoomableState: ZoomableState,
+    dragGesturesEnabled: ZoomableState.() -> Boolean = { true },
     onSwipeLeft: () -> Unit = {},
     onSwipeRight: () -> Unit = {},
     minimumSwipeDistance: Int = 0,
@@ -198,40 +200,42 @@ public fun Zoomable(
                             transformEventCounter++
                         } while (!canceled && event.changes.fastAny { it.pressed } && relevant)
 
-                        do {
-                            awaitPointerEvent()
-                            drag = awaitTouchSlopOrCancellation(down.id) { change, over ->
-                                change.consumePositionChange()
-                                overSlop = over
-                            }
-                        } while (drag != null && !drag.positionChangeConsumed())
-                        if (drag != null) {
-                            dragOffset = Offset.Zero
-                            if (zoomableState.scale.value !in 0.92f..1.08f) {
-                                coroutineScope.launch {
-                                    zoomableState.transform {
-                                        transformBy(1f, overSlop, 0f)
-                                    }
+                        if (zoomableState.dragGesturesEnabled()) {
+                            do {
+                                awaitPointerEvent()
+                                drag = awaitTouchSlopOrCancellation(down.id) { change, over ->
+                                    change.consumePositionChange()
+                                    overSlop = over
                                 }
-                            } else {
-                                dragOffset += overSlop
-                            }
-                            if (drag(drag.id) {
-                                    if (zoomableState.scale.value !in 0.92f..1.08f) {
-                                        zoomableState.offset.value += it.positionChange()
-                                    } else {
-                                        dragOffset += it.positionChange()
+                            } while (drag != null && !drag.positionChangeConsumed())
+                            if (drag != null) {
+                                dragOffset = Offset.Zero
+                                if (zoomableState.scale.value !in 0.92f..1.08f) {
+                                    coroutineScope.launch {
+                                        zoomableState.transform {
+                                            transformBy(1f, overSlop, 0f)
+                                        }
                                     }
-                                    it.consumePositionChange()
+                                } else {
+                                    dragOffset += overSlop
                                 }
-                            ) {
-                                if (zoomableState.scale.value in 0.92f..1.08f) {
-                                    val offsetX = dragOffset.x
-                                    if (offsetX > minimumSwipeDistance) {
-                                        onSwipeRight()
+                                if (drag(drag.id) {
+                                        if (zoomableState.scale.value !in 0.92f..1.08f) {
+                                            zoomableState.offset.value += it.positionChange()
+                                        } else {
+                                            dragOffset += it.positionChange()
+                                        }
+                                        it.consumePositionChange()
+                                    }
+                                ) {
+                                    if (zoomableState.scale.value in 0.92f..1.08f) {
+                                        val offsetX = dragOffset.x
+                                        if (offsetX > minimumSwipeDistance) {
+                                            onSwipeRight()
 
-                                    } else if (offsetX < -minimumSwipeDistance) {
-                                        onSwipeLeft()
+                                        } else if (offsetX < -minimumSwipeDistance) {
+                                            onSwipeLeft()
+                                        }
                                     }
                                 }
                             }