ADFA-1428 - ADFA-1439 | Refactor constraint handling and centralize position restoration

common/src/main/java/com/itsaky/androidide/utils/ViewExtensions.kt

@@ -131,8 +131,8 @@ fun AlertDialog.onLongPress(listener: (View) -> Boolean) {
 
 @SuppressLint("ClickableViewAccessibility")
 fun View.handleLongClicksAndDrag(
+ onDrop: ((View, Float, Float) -> Unit)? = null,
  onLongPress: (View) -> Unit,
- onDrag: (View) -> Unit
 ) {
  var viewInitialX = 0f
  var viewInitialY = 0f
@@ -198,10 +198,9 @@ fun View.handleLongClicksAndDrag(
  longPressFired = false 
 
  if (wasDraggingDuringGesture) {
-onDrag(view) 
+onDrop?.invoke(view, view.x, view.y)
  return@setOnTouchListener true
  }
-
  if (wasLongPressFiredDuringGesture) {
  return@setOnTouchListener true
  }

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

@@ -15,6 +15,7 @@ import android.widget.LinearLayout
 import android.widget.Spinner
 import android.widget.Toast
 import androidx.appcompat.widget.TooltipCompat
+import androidx.constraintlayout.widget.ConstraintLayout
 import androidx.core.view.isEmpty
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
@@ -52,6 +53,7 @@ import org.appdevforall.codeonthego.layouteditor.managers.PreferencesManager
 import org.appdevforall.codeonthego.layouteditor.managers.UndoRedoManager
 import org.appdevforall.codeonthego.layouteditor.tools.XmlLayoutGenerator
 import org.appdevforall.codeonthego.layouteditor.tools.XmlLayoutParser
+import org.appdevforall.codeonthego.layouteditor.utils.restorePositionsAfterLoad
 import org.appdevforall.codeonthego.layouteditor.utils.ArgumentUtil.parseType
 import org.appdevforall.codeonthego.layouteditor.utils.Constants
 import org.appdevforall.codeonthego.layouteditor.utils.FileUtil
@@ -86,6 +88,8 @@ class DesignEditor : LinearLayout {
  private var isModified = false
  private lateinit var preferencesManager: PreferencesManager
  private var parser: XmlLayoutParser? = null
+ private val attrTranslationX = "android:translationX"
+ private val attrTranslationY = "android:translationY"
 
  init {
  initAttributes()
@@ -217,6 +221,52 @@ 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 ->
@@ -256,10 +306,7 @@ class DesignEditor : LinearLayout {
 
  if (index != newIndex) {
  parent.removeView(shadow)
- try {
- parent.addView(shadow, newIndex)
- } catch (_: IllegalStateException) {
- }
+ runCatching { parent.addView(shadow, newIndex) }
  }
  } else {
  if (shadow.parent !== parent) addWidget(shadow, parent, event)
@@ -280,6 +327,7 @@ class DesignEditor : LinearLayout {
  if (parent is DesignEditor) parent = getChildAt(0) as ViewGroup
  }
  }
+
  if (draggedView == null) {
  @Suppress("UNCHECKED_CAST") val data: HashMap<String, Any> =
  event.localState as HashMap<String, Any>
@@ -334,12 +382,17 @@ class DesignEditor : LinearLayout {
 
  if (data.containsKey(Constants.KEY_DEFAULT_ATTRS)) {
  @Suppress("UNCHECKED_CAST")
-initializer.applyDefaultAttributes(
- newView,
- data[Constants.KEY_DEFAULT_ATTRS] as MutableMap<String, String>
- )
+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)
+ val rootLayout = getChildAt(0)
+ restorePositionsAfterLoad(rootLayout, viewAttributeMap)
  } else addWidget(draggedView, parent, event)
+
  updateStructure()
  updateUndoRedoHistory()
  }
@@ -499,8 +552,13 @@ class DesignEditor : LinearLayout {
  tag = view.javaClass.superclass.name
  )
  },
- onDrag = {
- view.startDragAndDrop(null, DragShadowBuilder(view), view, 0)
+ onDrop = { child, x, y ->
+ positionAtDrop(child, x, y)
+ val rootLayout = getChildAt(0)
+ restorePositionsAfterLoad(rootLayout, viewAttributeMap)
+
+ updateStructure()
+ updateUndoRedoHistory()
  }
  )
  }

layouteditor/src/main/java/org/appdevforall/codeonthego/layouteditor/tools/XmlLayoutParser.kt

@@ -15,6 +15,7 @@ import org.appdevforall.codeonthego.layouteditor.utils.Constants
 import org.appdevforall.codeonthego.layouteditor.utils.FileUtil
 import org.appdevforall.codeonthego.layouteditor.utils.InvokeUtil.createView
 import org.appdevforall.codeonthego.layouteditor.utils.InvokeUtil.invokeMethod
+import org.appdevforall.codeonthego.layouteditor.utils.restorePositionsAfterLoad
 import org.xmlpull.v1.XmlPullParser
 import org.xmlpull.v1.XmlPullParserException
 import org.xmlpull.v1.XmlPullParserFactory
@@ -180,6 +181,10 @@ class XmlLayoutParser(context: Context) {
  }
  parser.next()
  }
+
+ root?.let {
+ restorePositionsAfterLoad(it, viewAttributeMap)
+ }
  }
 
  private fun applyAttributes(target: View, attributeMap: AttributeMap) {

layouteditor/src/main/java/org/appdevforall/codeonthego/layouteditor/utils/ConstraintUtils.kt

@@ -0,0 +1,134 @@
+package org.appdevforall.codeonthego.layouteditor.utils
+
+import android.view.View
+import androidx.constraintlayout.widget.ConstraintLayout
+import androidx.constraintlayout.widget.ConstraintSet
+import androidx.core.view.doOnLayout
+import org.appdevforall.codeonthego.layouteditor.editor.initializer.AttributeMap
+
+
+/**
+ * Modifies a [ConstraintSet] to apply basic constraints to a specific view.
+ *
+ * - Anchors the view to the parent's START and TOP.
+ * - Clears existing END and BOTTOM constraints to avoid conflicts.
+ * - Sets START and TOP margins in **pixels** using the provided values.
+ *
+ * @param constraintSet The [ConstraintSet] instance to modify.
+ * @param viewId The ID of the target view.
+ * @param startPxMargin The START margin in **pixels**.
+ * @param topPxMargin The TOP margin in **pixels**.
+ */
+private fun modifyConstraintsForView(constraintSet: ConstraintSet, viewId: Int, startPxMargin: Int, topPxMargin: Int) {
+	constraintSet.clear(viewId, ConstraintSet.BOTTOM)
+	constraintSet.clear(viewId, ConstraintSet.END)
+	constraintSet.connect(viewId, ConstraintSet.START, ConstraintSet.PARENT_ID, ConstraintSet.START)
+	constraintSet.connect(viewId, ConstraintSet.TOP, ConstraintSet.PARENT_ID, ConstraintSet.TOP)
+	constraintSet.setMargin(viewId, ConstraintSet.START, startPxMargin)
+	constraintSet.setMargin(viewId, ConstraintSet.TOP, topPxMargin)
+}
+
+/**
+ * Converts a dimension string (e.g., `"12px"`, `"8dp"`, `"10dip"`, or `"14"`)
+ * into pixels using the given [density].
+ *
+ * Supported suffixes:
+ * - `"px"` → interpreted as raw pixels.
+ * - `"dp"` or `"dip"` → multiplied by display density.
+ * - No suffix → assumed to be dp and multiplied by density.
+ *
+ * @receiver The dimension string to convert.
+ * @param density The display density for dp-to-px conversion.
+ * @return The equivalent pixel value, or `0f` if parsing fails.
+ */
+private fun String.toPx(density: Float): Float {
+	val trimmed = trim()
+	return when {
+ trimmed.endsWith("px", true) -> trimmed.dropLast(2).toFloatOrNull()?.takeIf { it.isFinite() } ?: 0f
+ trimmed.endsWith("dp", true) -> (trimmed.dropLast(2).toFloatOrNull() ?: 0f) * density
+ trimmed.endsWith("dip", true) -> (trimmed.dropLast(3).toFloatOrNull() ?: 0f) * density
+ else -> (trimmed.toFloatOrNull() ?: 0f) * density // assume dp if no suffix
+	}
+}
+
+/**
+ * Helper class to store a set of constraint changes for a single view.
+ */
+private data class ViewConstraintChange(
+ val viewId: Int,
+ val startMargin: Int,
+ val topMargin: Int
+)
+
+/**
+ * Efficiently restores the positions of draggable views by reapplying constraints
+ * after the layout has finished rendering.
+ *
+ * This function uses a two-pass batching mechanism for efficiency:
+ *
+ * 1. **Collection Pass:** Iterates [attributeMap], calculates pixel margins,
+ * resets [View.translationX]/[View.translationY] to 0, and groups all
+ * required changes by their parent [ConstraintLayout].
+ * 2. **Application Pass:** Iterates over each unique parent [ConstraintLayout],
+ * clones its state into a *single* [ConstraintSet], applies *all*
+ * changes for that group using [modifyConstraintsForView], and then calls
+ * [ConstraintSet.applyTo] **once** per container.
+ *
+ * This ensures only one layout pass is triggered per [ConstraintLayout] container,
+ * instead of N passes.
+ *
+ * @param rootView The root [View] to observe for layout completion.
+ * @param attributeMap A [Map] of [View]s to their corresponding [AttributeMap].
+ */
+fun restorePositionsAfterLoad(rootView: View, attributeMap: Map<View, AttributeMap>) {
+	rootView.doOnLayout { container ->
+ val density = container.resources.displayMetrics.density
+
+ val changesByContainer = mutableMapOf<ConstraintLayout, MutableList<ViewConstraintChange>>()
+
+ // --- 1. COLLECTION PASS ---
+ attributeMap.forEach { (view, attrs) ->
+ val constraintContainer = view.parent as? ConstraintLayout ?: return@forEach
+
+ val txStr = attrs.getValue("app:layout_marginStart")
+ val tyStr = attrs.getValue("app:layout_marginTop")
+
+ if (txStr.isNotEmpty() || tyStr.isNotEmpty()) {
+ val maxX = (constraintContainer.width - view.width).coerceAtLeast(0).toFloat()
+ val maxY = (constraintContainer.height - view.height).coerceAtLeast(0).toFloat()
+
+ val txPx = txStr.toPx(density).coerceIn(0f, maxX)
+ val tyPx = tyStr.toPx(density).coerceIn(0f, maxY)
+
+ view.translationX = 0f
+ view.translationY = 0f
+
+ val changesList = changesByContainer.getOrPut(constraintContainer) { mutableListOf() }
+
+ changesList.add(ViewConstraintChange(
+ viewId = view.id,
+ startMargin = txPx.toInt(),
+ topMargin = tyPx.toInt()
+ ))
+ }
+ }
+
+ // --- 2. APPLICATION PASS ---
+ changesByContainer.forEach { (container, changeList) ->
+ val constraintSet = ConstraintSet()
+
+ constraintSet.clone(container)
+
+ changeList.forEach { change ->
+ modifyConstraintsForView(
+ constraintSet,
+ change.viewId,
+ change.startMargin,
+ change.topMargin
+ )
+ }
+
+ constraintSet.applyTo(container)
+ }
+	}
+}

templates-impl/src/main/java/com/itsaky/androidide/templates/impl/base/layout.kt

@@ -32,7 +32,9 @@ internal fun baseLayoutContentMain() = """
  app:layout_constraintBottom_toBottomOf="parent"
  app:layout_constraintEnd_toEndOf="parent"
  app:layout_constraintStart_toStartOf="parent"
- app:layout_constraintTop_toTopOf="parent" />
+ app:layout_constraintTop_toTopOf="parent"
+ app:layout_constrainedWidth="true"
+ app:layout_constrainedHeight="true" />
 
 </androidx.constraintlayout.widget.ConstraintLayout>
 """.trim()