ADFA-2023 | Refactor layout positioning and drop/restore workflow

layouteditor/src/main/assets/palette/buttons.json

@@ -12,7 +12,7 @@
         "className": "org.appdevforall.codeonthego.layouteditor.editor.palette.buttons.ImageButtonDesign",
         "iconName": "ic_palette_image_button",
         "defaultAttributes": {
-            "android:src": "@drawable/default_image"
+            "android:src": "@drawable/ic_launcher_round"
         }
     },
     {

layouteditor/src/main/assets/palette/common.json

@@ -62,7 +62,7 @@
         "defaultAttributes": {
             "android:layout_width": "48dp",
             "android:layout_height": "48dp",
-            "android:src": "@drawable/default_image"
+            "android:src": "@drawable/ic_launcher_round"
         }
     },
     {

layouteditor/src/main/assets/palette/widgets.json

@@ -16,7 +16,7 @@
         "defaultAttributes": {
             "android:layout_width": "48dp",
             "android:layout_height": "48dp",
-            "android:src": "@drawable/default_image"
+            "android:src": "@drawable/ic_launcher_round"
         }
     },
     {

layouteditor/src/main/java/org/appdevforall/codeonthego/layouteditor/editor/DesignEditor.kt

@@ -45,6 +45,8 @@ import org.appdevforall.codeonthego.layouteditor.editor.dialogs.StringDialog
 import org.appdevforall.codeonthego.layouteditor.editor.dialogs.ViewDialog
 import org.appdevforall.codeonthego.layouteditor.editor.initializer.AttributeInitializer
 import org.appdevforall.codeonthego.layouteditor.editor.initializer.AttributeMap
+import org.appdevforall.codeonthego.layouteditor.editor.positioning.positionAtDrop
+import org.appdevforall.codeonthego.layouteditor.editor.positioning.restoreSingleViewPosition
 import org.appdevforall.codeonthego.layouteditor.managers.IdManager
 import org.appdevforall.codeonthego.layouteditor.managers.IdManager.addId
 import org.appdevforall.codeonthego.layouteditor.managers.IdManager.getViewId
@@ -58,7 +60,6 @@ import org.appdevforall.codeonthego.layouteditor.utils.Constants
 import org.appdevforall.codeonthego.layouteditor.utils.FileUtil
 import org.appdevforall.codeonthego.layouteditor.utils.InvokeUtil
 import org.appdevforall.codeonthego.layouteditor.utils.Utils
-import org.appdevforall.codeonthego.layouteditor.utils.restorePositionsAfterLoad
 import org.appdevforall.codeonthego.layouteditor.views.StructureView
 
 class DesignEditor : LinearLayout {
@@ -88,6 +89,9 @@ class DesignEditor : LinearLayout {
 	private var parser: XmlLayoutParser? = null
 	private val attrTranslationX = "android:translationX"
 	private val attrTranslationY = "android:translationY"
+	private val widgetIdOverrides = mapOf(
+		"switch" to "switchWidget",
+	)
 
 	init {
 		viewAttributeMap = HashMap()
@@ -262,55 +266,6 @@ class DesignEditor : LinearLayout {
 		}
 	}
 
-	/**
-	 * Updates the **stored attributes** in [viewAttributeMap] for a [child] view
-	 * after it's "dropped" at a new position (x, y) within its [ConstraintLayout] parent.
-	 *
-	 * This function performs the following actions:
-	 * 1.  Clamps the raw (x, y) pixel coordinates to ensure the view stays within the
-	 * parent container's bounds.
-	 * 2.  Converts the clamped pixel coordinates to dp using the screen density.
-	 * 3.  Updates the [viewAttributeMap] for the [child]:
-	 * - Clears any existing `...constraintBottom_toBottomOf` or `...constraintEnd_toEndOf` attributes.
-	 * - Sets `app:layout_constraintStart_toStartOf = "parent"`
-	 * - Sets `app:layout_constraintTop_toTopOf = "parent"`
-	 * - Sets `app:layout_marginStart = "<x>dp"`
-	 * - Sets `app:layout_marginTop = "<y>dp"`
-	 *
-	 * @param child The view being positioned.
-	 * @param x The target X coordinate in container pixels.
-	 * @param y The target Y coordinate in container pixels.
-	 */
-	private fun positionAtDrop(
-		child: View,
-		x: Float,
-		y: Float,
-	) {
-		val container = child.parent as? ConstraintLayout ?: return
-		val density = container.resources.displayMetrics.density
-
-		val maxX = (container.width - child.width).coerceAtLeast(0).toFloat()
-		val maxY = (container.height - child.height).coerceAtLeast(0).toFloat()
-
-		val xPx = x.coerceIn(0f, maxX)
-		val yPx = y.coerceIn(0f, maxY)
-
-		val xDp = xPx / density
-		val yDp = yPx / density
-
-		viewAttributeMap[child]?.apply {
-			if (contains("app:layout_constraintBottom_toBottomOf")) removeValue("app:layout_constraintBottom_toBottomOf")
-			if (contains("app:layout_constraintEnd_toEndOf")) removeValue("app:layout_constraintEnd_toEndOf")
-
-			putValue("app:layout_constraintStart_toStartOf", "parent")
-			putValue("app:layout_constraintTop_toTopOf", "parent")
-			putValue("app:layout_marginStart", "${xDp}dp")
-			putValue("app:layout_marginTop", "${yDp}dp")
-		}
-
-		markAsModified()
-	}
-
 	private fun setDragListener(group: ViewGroup) {
 		group.setOnDragListener(
 			OnDragListener { host, event ->
@@ -407,12 +362,12 @@ class DesignEditor : LinearLayout {
 							if (newView is EditText) newView.isFocusable = false
 
 							val map = AttributeMap()
-							val id =
-								getIdForNewView(
-									newView.javaClass.superclass.simpleName
-										.replace(" ".toRegex(), "_")
-										.lowercase(),
-								)
+							val raw = newView.javaClass.superclass.simpleName
+								.replace(" ".toRegex(), "_")
+								.lowercase()
+							val sanitized = sanitizeIdName(raw)
+							val id = getIdForNewView(sanitized)
+
 							IdManager.addNewId(newView, id)
 							map.putValue("android:id", "@+id/$id")
 							map.putValue("android:layout_width", "wrap_content")
@@ -437,28 +392,25 @@ class DesignEditor : LinearLayout {
 							}
 
 							if (data.containsKey(Constants.KEY_DEFAULT_ATTRS)) {
-								ensureInitializerInitialized()
+								initAttributeInitializer()
 								@Suppress("UNCHECKED_CAST")
 								val defaults = (data[Constants.KEY_DEFAULT_ATTRS] as MutableMap<String, String>).toMutableMap()
 								defaults.remove(attrTranslationX)
 								defaults.remove(attrTranslationY)
 								initializer.applyDefaultAttributes(newView, defaults)
 							}
 
-							positionAtDrop(newView, event.x, event.y)
+							positionAtDrop(newView, event.x, event.y, viewAttributeMap)
 							val rootLayout = getChildAt(0)
-							restorePositionsAfterLoad(rootLayout, viewAttributeMap)
-						} else {
-							addWidget(draggedView, parent, event)
-						}
+							restoreSingleViewPosition(rootLayout, newView, viewAttributeMap)
+						} else addWidget(draggedView, parent, event)
 
 						updateStructure()
 						updateUndoRedoHistory()
 					}
 				}
 				true
-			},
-		)
+			})
 	}
 
 	private fun getIdForNewView(name: String): String {
@@ -481,6 +433,8 @@ class DesignEditor : LinearLayout {
 		return id
 	}
 
+	private fun sanitizeIdName(base: String): String = widgetIdOverrides[base] ?: base
+
 	fun loadLayoutFromParser(xml: String) {
 		clearAll()
 		if (xml.isEmpty()) return
@@ -509,7 +463,7 @@ class DesignEditor : LinearLayout {
 		updateStructure()
 		toggleStrokeWidgets()
 
-		ensureInitializerInitialized()
+		initAttributeInitializer()
 	}
 
 	private fun ensureConstraintsApplied() {
@@ -623,9 +577,9 @@ class DesignEditor : LinearLayout {
 				)
 			},
 			onDrop = { child, x, y ->
-				positionAtDrop(child, x, y)
+				positionAtDrop(child, x, y, viewAttributeMap)
 				val rootLayout = getChildAt(0)
-				restorePositionsAfterLoad(rootLayout, viewAttributeMap)
+				restoreSingleViewPosition(rootLayout, child, viewAttributeMap)
 
 				updateStructure()
 				updateUndoRedoHistory()
@@ -1075,15 +1029,13 @@ class DesignEditor : LinearLayout {
 		return target
 	}
 
-	private fun ensureInitializerInitialized() {
-		if (!::initializer.isInitialized) {
-			initializer = AttributeInitializer(
-				context,
-				viewAttributeMap,
-				getAttributes(context),
-				getParentAttributes(context)
-			)
-		}
+	private fun initAttributeInitializer() {
+		initializer = AttributeInitializer(
+			context,
+			viewAttributeMap,
+			getAttributes(context),
+			getParentAttributes(context)
+		)
 	}
 
 	enum class ViewType {

layouteditor/src/main/java/org/appdevforall/codeonthego/layouteditor/editor/positioning/LayoutDropHandler.kt

@@ -0,0 +1,66 @@
+package org.appdevforall.codeonthego.layouteditor.editor.positioning
+
+import android.view.View
+import android.view.ViewGroup
+import android.widget.FrameLayout
+import android.widget.GridLayout
+import android.widget.LinearLayout
+import android.widget.RelativeLayout
+import androidx.constraintlayout.widget.ConstraintLayout
+import androidx.coordinatorlayout.widget.CoordinatorLayout
+import org.appdevforall.codeonthego.layouteditor.editor.initializer.AttributeMap
+
+
+/**
+ * Updates the stored attributes for a [child] view after it is "dropped"
+ * at a new position (x, y) within its parent [ViewGroup].
+ *
+ * This function orchestrates the process of:
+ * 1. Calculating the final, clamped coordinates in Dp.
+ * 2. Clearing any previous positioning attributes to prevent conflicts.
+ * 3. Applying the correct new attributes based on the parent's layout type.
+ *
+ * @param child The view being positioned.
+ * @param x The raw target X coordinate in container pixels.
+ * @param y The raw target Y coordinate in container pixels.
+ */
+fun positionAtDrop(child: View, x: Float, y: Float, viewAttributeMap: HashMap<View, AttributeMap>) {
+    val container = child.parent as? ViewGroup ?: return
+
+    val density = container.resources.displayMetrics.density
+    val coords = calculateDropCoordinatesInDp(container, child, x, y, density)
+
+    val attributes = viewAttributeMap[child] ?: return
+
+    clearPositioningAttributes(attributes)
+
+    applyLayoutAttributes(container, child, attributes, coords, x, y, viewAttributeMap)
+}
+
+/**
+ * Acts as a "dynamic mapper" or "strategy" function.
+ * It detects the type of the [container] and calls the appropriate
+ * helper function to apply layout-specific attributes.
+ *
+ * @param container The parent ViewGroup.
+ * @param attributes The AttributeMap for the child view.
+ * @param coords The final Dp coordinates to apply.
+ */
+internal fun applyLayoutAttributes(
+    container: ViewGroup,
+    child: View,
+    attributes: AttributeMap,
+    coords: DpCoordinates,
+    x: Float,
+    y: Float,
+    fullAttributeMap: HashMap<View, AttributeMap>
+) {
+    when (container) {
+        is ConstraintLayout -> applyConstraintLayoutAttributes(attributes, coords)
+        is FrameLayout, is CoordinatorLayout -> applyGravityMarginAttributes(attributes, coords)
+        is RelativeLayout -> applyRelativeLayoutAttributes(attributes, coords)
+        is LinearLayout -> applyDragReorder(container, child, x, y)
+        is GridLayout -> applyGridLayoutAttributes(container, child, attributes, x, y, fullAttributeMap)
+        else -> applyGenericLayoutAttributes(attributes, coords)
+    }
+}