add Animate state, modifier and demo

Author: SmartToolFactory

app/src/main/java/com/smarttoolfactory/composeimage/demo/zoom/AnimatedZoomDemo.kt

@@ -0,0 +1,49 @@
+package com.smarttoolfactory.composeimage.demo.zoom
+
+import androidx.compose.foundation.background
+import androidx.compose.foundation.border
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.fillMaxSize
+import androidx.compose.foundation.layout.size
+import androidx.compose.material.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.unit.dp
+import com.smarttoolfactory.image.zoom.AnimatedZoomLayout2
+
+@Composable
+fun AnimatedZoomDemo() {
+
+    Column(modifier = Modifier.fillMaxSize()) {
+        AnimatedZoomLayout2(
+            modifier = Modifier
+                .fillMaxSize()
+                .border(2.dp, Color.Green)
+        ) {
+            Text(
+                modifier = Modifier
+                    .size(200.dp)
+                    .background(Color.Yellow),
+                text = "Hello World........\n" +
+                        "asdamsdalşsdkasşl\n" +
+                        "asdasdaskdk\n" +
+                " asads dasdasdasd asdasdasd",
+            )
+        }
+
+//        AnimatedZoomLayout2(
+//            modifier = Modifier
+//                .fillMaxWidth()
+//
+//                .border(2.dp, Color.Green)
+//        ) {
+//            Text(
+//                modifier = Modifier
+//                    .size(100.dp)
+//                    .background(Color.Yellow),
+//                text = "Hello World",
+//            )
+//        }
+    }
+}

image/src/main/java/com/smarttoolfactory/image/zoom/AnimatedZoomLayout.kt

@@ -0,0 +1,63 @@
+package com.smarttoolfactory.image.zoom
+
+import androidx.compose.foundation.border
+import androidx.compose.foundation.layout.Box
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Alignment
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.unit.DpSize
+import androidx.compose.ui.unit.dp
+import com.smarttoolfactory.image.DimensionSubcomposeLayout
+
+@Composable
+fun AnimatedZoomLayout(
+    modifier: Modifier = Modifier,
+    content: @Composable () -> Unit
+) {
+
+    val density = LocalDensity.current
+
+    DimensionSubcomposeLayout(
+        placeMainContent = false,
+        mainContent = { content() }
+    ) {
+        Box(
+            modifier
+                .border(5.dp, Color.Red)
+                .animatedZoom(
+                    animatedZoomState = rememberAnimatedZoomState(
+                        minZoom = .5f,
+                        maxZoom = 30f
+                    ),
+                ),
+            contentAlignment = Alignment.Center
+        ) {
+            content()
+        }
+    }
+}
+
+@Composable
+fun AnimatedZoomLayout2(
+    modifier: Modifier = Modifier,
+    content: @Composable () -> Unit
+) {
+
+    Box(
+        modifier
+            .border(4.dp, Color.Red)
+            .animatedZoom(
+                animatedZoomState = rememberAnimatedZoomState(
+                    minZoom = .5f,
+                    maxZoom = 30f,
+                    contentSize = DpSize(200.dp, 200.dp)
+                )
+            ),
+        contentAlignment = Alignment.Center
+    ) {
+        content()
+    }
+
+}

image/src/main/java/com/smarttoolfactory/image/zoom/AnimatedZoomModifier.kt

@@ -0,0 +1,97 @@
+package com.smarttoolfactory.image.zoom
+
+import androidx.compose.foundation.gestures.detectTapGestures
+import androidx.compose.runtime.rememberCoroutineScope
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.composed
+import androidx.compose.ui.draw.clipToBounds
+import androidx.compose.ui.graphics.graphicsLayer
+import androidx.compose.ui.input.pointer.pointerInput
+import com.smarttoolfactory.gesture.detectTransformGestures
+import com.smarttoolfactory.image.util.update
+import kotlinx.coroutines.launch
+
+/**
+* Modifier that zooms in or out of Composable set to. This zoom modifier has option
+* to move back to bounds with an animation or option to have fling gesture when user removes
+* from screen while velocity is higher than threshold to have smooth touch effect.
+*
+* @param key is used for [Modifier.pointerInput] to restart closure when any keys assigned
+* change
+* @param consume flag to prevent other gestures such as scroll, drag or transform to get
+* @param clip when set to true clips to parent bounds. Anything outside parent bounds is not
+* drawn
+* empty space on sides or edges of parent.
+* [EnhancedZoomData]  of this modifier
+*/
+fun Modifier.animatedZoom(
+    key: Any? = Unit,
+    consume: Boolean = true,
+    clip: Boolean = true,
+    animatedZoomState: AnimatedZoomState,
+) = composed(
+
+    factory = {
+
+        val coroutineScope = rememberCoroutineScope()
+
+        val boundPan = animatedZoomState.limitPan && !animatedZoomState.rotatable
+        val clipToBounds = (clip || boundPan)
+
+        val transformModifier = Modifier.pointerInput(key) {
+            // Pass size of this Composable this Modifier is attached for constraining operations
+            // inside this bounds
+            animatedZoomState.size = this.size
+            detectTransformGestures(
+                consume = consume,
+                onGestureEnd = {
+                    coroutineScope.launch {
+                        animatedZoomState.onGestureEnd {
+                        }
+                    }
+                },
+                onGesture = { centroid, pan, zoom, rotate, mainPointer, pointerList ->
+
+                    coroutineScope.launch {
+                        animatedZoomState.onGesture(
+                            centroid = centroid,
+                            pan = pan,
+                            zoom = zoom,
+                            rotation = rotate,
+                            mainPointer = mainPointer,
+                            changes = pointerList
+                        )
+                    }
+                }
+            )
+        }
+
+        val tapModifier = Modifier.pointerInput(key) {
+            // Pass size of this Composable this Modifier is attached for constraining operations
+            // inside this bounds
+            animatedZoomState.size = this.size
+            detectTapGestures(
+                onDoubleTap = {
+                    coroutineScope.launch {
+                        animatedZoomState.onDoubleTap {}
+                    }
+                }
+            )
+        }
+
+        val graphicsModifier = Modifier.graphicsLayer {
+            this.update(animatedZoomState)
+        }
+
+        this.then(
+            (if (clipToBounds) Modifier.clipToBounds() else Modifier)
+                .then(tapModifier)
+                .then(transformModifier)
+                .then(graphicsModifier)
+        )
+    },
+    inspectorInfo = {
+        name = "animatedZoomState"
+
+    }
+)