Updated imageviewer example to use CoroutineScope (loading and proces…

…sing images).

examples/imageviewer/android/src/main/java/example/imageviewer/MainActivity.kt

@@ -3,7 +3,7 @@ package example.imageviewer
 import android.os.Bundle
 import androidx.appcompat.app.AppCompatActivity
 import androidx.activity.compose.setContent
-import example.imageviewer.view.BuildAppUI
+import example.imageviewer.view.AppUI
 import example.imageviewer.model.ContentState
 import example.imageviewer.model.ImageRepository
 
@@ -17,7 +17,7 @@ class MainActivity : AppCompatActivity() {
         )
 
         setContent {
-            BuildAppUI(content)
+            AppUI(content)
         }
     }
 }

examples/imageviewer/build.gradle.kts

@@ -7,7 +7,7 @@ buildscript {
 
     dependencies {
         // __LATEST_COMPOSE_RELEASE_VERSION__
-        classpath("org.jetbrains.compose:compose-gradle-plugin:1.0.0-alpha1-rc1")
+        classpath("org.jetbrains.compose:compose-gradle-plugin:1.0.0-alpha1-rc3")
         classpath("com.android.tools.build:gradle:7.0.0")
         classpath(kotlin("gradle-plugin", version = "1.5.21"))
     }

examples/imageviewer/common/src/androidMain/kotlin/example/imageviewer/model/ContentState.kt → examples/imageviewer/common/src/androidMain/kotlin/example/imageviewer/model/AndroidContentState.kt

@@ -31,7 +31,7 @@ object ContentState {
         this.uriRepository = uriRepository
         repository = ImageRepository(uriRepository)
         appliedFilters = FiltersManager(context)
-        isAppUIReady.value = false
+        isContentReady.value = false
 
         initData()
 
@@ -50,9 +50,14 @@ object ContentState {
         return context.resources.configuration.orientation
     }
 
-    private val isAppUIReady = mutableStateOf(false)
+    private val isAppReady = mutableStateOf(false)
+    fun isAppReady(): Boolean {
+        return isAppReady.value
+    }
+
+    private val isContentReady = mutableStateOf(false)
     fun isContentReady(): Boolean {
-        return isAppUIReady.value
+        return isContentReady.value
     }
 
     fun getString(id: Int): String {
@@ -142,7 +147,7 @@ object ContentState {
 
     // application content initialization
     private fun initData() {
-        if (isAppUIReady.value)
+        if (isContentReady.value)
             return
 
         val directory = context.cacheDir.absolutePath
@@ -158,7 +163,7 @@ object ContentState {
                                 getString(R.string.repo_invalid),
                                 context
                             )
-                            isAppUIReady.value = true
+                            onContentReady()
                         }
                         return@execute
                     }
@@ -171,7 +176,7 @@ object ContentState {
                                 getString(R.string.repo_empty),
                                 context
                             )
-                            isAppUIReady.value = true
+                            onContentReady()
                         }
                     } else {
                         val picture = loadFullImage(imageList[0])
@@ -186,7 +191,7 @@ object ContentState {
                                 mainImage.value = MainImageWrapper.getImage()
                                 currentImageIndex.value = MainImageWrapper.getId()
                             }
-                            isAppUIReady.value = true
+                            onContentReady()
                         }
                     }
                 } else {
@@ -195,7 +200,7 @@ object ContentState {
                             getString(R.string.no_internet),
                             context
                         )
-                        isAppUIReady.value = true
+                        onContentReady()
                     }
                 }
             } catch (e: Exception) {
@@ -210,17 +215,18 @@ object ContentState {
     }
 
     fun fullscreen(picture: Picture) {
-        isAppUIReady.value = false
+        isContentReady.value = false
         AppState.screenState(ScreenType.FullscreenImage)
         setMainImage(picture)
     }
 
     fun setMainImage(picture: Picture) {
         if (MainImageWrapper.getId() == picture.id) {
             if (!isContentReady())
-                isAppUIReady.value = true
+                onContentReady()
             return
         }
+        isContentReady.value = false
 
         executor.execute {
             if (isInternetAvailable()) {
@@ -230,7 +236,7 @@ object ContentState {
 
                 handler.post {
                     wrapPictureIntoMainImage(fullSizePicture)
-                    isAppUIReady.value = true
+                    onContentReady()
                 }
             } else {
                 handler.post {
@@ -244,6 +250,11 @@ object ContentState {
         }
     }
 
+    private fun onContentReady() {
+        isContentReady.value = true
+        isAppReady.value = true
+    }
+
     private fun wrapPictureIntoMainImage(picture: Picture) {
         MainImageWrapper.wrapPicture(picture)
         MainImageWrapper.saveOrigin()
@@ -282,8 +293,9 @@ object ContentState {
             if (isInternetAvailable()) {
                 handler.post {
                     clearCache(context)
+                    MainImageWrapper.clear()
                     miniatures.clear()
-                    isAppUIReady.value = false
+                    isContentReady.value = false
                     initData()
                 }
             } else {
@@ -334,6 +346,10 @@ private object MainImageWrapper {
         return (picture.value.name == "")
     }
 
+    fun clear() {
+        picture.value = Picture(image = Bitmap.createBitmap(1, 1, Bitmap.Config.ARGB_8888))
+    }
+
     fun getName(): String {
         return picture.value.name
     }

examples/imageviewer/common/src/androidMain/kotlin/example/imageviewer/utils/GraphicsMath.kt

@@ -8,6 +8,9 @@ import android.renderscript.Element
 import android.renderscript.RenderScript
 import android.renderscript.ScriptIntrinsicBlur
 import androidx.compose.ui.layout.ContentScale
+import kotlin.math.pow
+import kotlin.math.roundToInt
+import example.imageviewer.view.DragHandler
 
 fun scaleBitmapAspectRatio(
     bitmap: Bitmap,
@@ -116,3 +119,77 @@ fun displayWidth(): Int {
 fun displayHeight(): Int {
     return Resources.getSystem().displayMetrics.heightPixels
 }
+
+fun cropBitmapByScale(bitmap: Bitmap, scale: Float, drag: DragHandler): Bitmap {
+    val crop = cropBitmapByBounds(
+        bitmap,
+        getDisplayBounds(bitmap),
+        scale,
+        drag
+    )
+    return Bitmap.createBitmap(
+        bitmap,
+        crop.left,
+        crop.top,
+        crop.right - crop.left,
+        crop.bottom - crop.top
+    )
+}
+
+fun cropBitmapByBounds(
+    bitmap: Bitmap,
+    bounds: Rect,
+    scaleFactor: Float,
+    drag: DragHandler
+): Rect {
+    if (scaleFactor <= 1f)
+        return Rect(0, 0, bitmap.width, bitmap.height)
+
+    var scale = scaleFactor.toDouble().pow(1.4)
+
+    var boundW = (bounds.width() / scale).roundToInt()
+    var boundH = (bounds.height() / scale).roundToInt()
+
+    scale *= displayWidth() / bounds.width().toDouble()
+
+    val offsetX = drag.getAmount().x / scale
+    val offsetY = drag.getAmount().y / scale
+
+    if (boundW > bitmap.width) {
+        boundW = bitmap.width
+    }
+    if (boundH > bitmap.height) {
+        boundH = bitmap.height
+    }
+
+    val invisibleW = bitmap.width - boundW
+    var leftOffset = (invisibleW / 2.0 - offsetX).roundToInt().toFloat()
+
+    if (leftOffset > invisibleW) {
+        leftOffset = invisibleW.toFloat()
+        drag.getAmount().x = -((invisibleW / 2.0) * scale).roundToInt().toFloat()
+    }
+    if (leftOffset < 0) {
+        drag.getAmount().x = ((invisibleW / 2.0) * scale).roundToInt().toFloat()
+        leftOffset = 0f
+    }
+
+    val invisibleH = bitmap.height - boundH
+    var topOffset = (invisibleH / 2 - offsetY).roundToInt().toFloat()
+
+    if (topOffset > invisibleH) {
+        topOffset = invisibleH.toFloat()
+        drag.getAmount().y = -((invisibleH / 2.0) * scale).roundToInt().toFloat()
+    }
+    if (topOffset < 0) {
+        drag.getAmount().y = ((invisibleH / 2.0) * scale).roundToInt().toFloat()
+        topOffset = 0f
+    }
+
+    return Rect(
+        leftOffset.toInt(),
+        topOffset.toInt(),
+        (leftOffset + boundW).toInt(),
+        (topOffset + boundH).toInt()
+    )
+}

examples/imageviewer/common/src/androidMain/kotlin/example/imageviewer/view/AppUI.kt

@@ -14,18 +14,18 @@ import example.imageviewer.model.ContentState
 import example.imageviewer.style.Gray
 
 @Composable
-fun BuildAppUI(content: ContentState) {
+fun AppUI(content: ContentState) {
 
     Surface(
         modifier = Modifier.fillMaxSize(),
         color = Gray
     ) {
         when (AppState.screenState()) {
-            ScreenType.Main -> {
-                setMainScreen(content)
+            ScreenType.MainScreen -> {
+                MainScreen(content)
             }
             ScreenType.FullscreenImage -> {
-                setImageFullScreen(content)
+                FullscreenImage(content)
             }
         }
     }