IJP-1115 Kotlin UI DSL improvements / new Layout Manager

GitOrigin-RevId: ed5d7274e1a8d23ca2ed17e670d80fe457f20ee4

platform/platform-impl/src/com/intellij/ui/dsl/CellBuilder.kt

@@ -1,108 +1,25 @@
 // Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.ui.dsl
 
-import com.intellij.openapi.ui.panel.ComponentPanelBuilder
-import com.intellij.openapi.util.NlsContexts
-import com.intellij.ui.dsl.gridLayout.HorizontalAlign
-import com.intellij.ui.dsl.gridLayout.VerticalAlign
 import com.intellij.ui.layout.*
-import com.intellij.util.SmartList
 import org.jetbrains.annotations.ApiStatus
 import javax.swing.AbstractButton
 import javax.swing.JComponent
 import kotlin.reflect.KMutableProperty0
 
-@DslMarker
-private annotation class CellBuilderMarker
-
 @ApiStatus.Experimental
-@CellBuilderMarker
-open class CellBuilder<out T : JComponent>(
-  private val builder: PanelBuilder,
-  val component: T,
-  val viewComponent: JComponent = component) {
+interface CellBuilder<T : JComponent> : CellBuilderBase<CellBuilder<T>> {
 
-  var horizontalAlign = HorizontalAlign.LEFT
-    private set
-  var verticalAlign = VerticalAlign.CENTER
-    private set
-  var comment: JComponent? = null
-    private set
-  var rightGap = 0
-    private set
-  private var applyIfEnabled = false
+  fun applyToComponent(task: T.() -> Unit): CellBuilder<T>
 
-  fun applyToComponent(task: T.() -> Unit): CellBuilder<T> {
-    component.task()
-    return this
-  }
-
-  fun enabled(isEnabled: Boolean): CellBuilder<T> {
-    viewComponent.isEnabled = isEnabled
-    return this
-  }
+  fun enabled(isEnabled: Boolean): CellBuilder<T>
 
   /**
    * If this method is called, the value of the component will be stored to the backing property only if the component is enabled
    */
-  fun applyIfEnabled(): CellBuilder<T> {
-    applyIfEnabled = true
-    return this
-  }
+  fun applyIfEnabled(): CellBuilder<T>
 
-  fun alignHorizontal(horizontalAlign: HorizontalAlign): CellBuilder<T> {
-    this.horizontalAlign = horizontalAlign
-    return this
-  }
-
-  fun alignVertical(verticalAlign: VerticalAlign): CellBuilder<T> {
-    this.verticalAlign = verticalAlign
-    return this
-  }
-
-  /**
-   * Separates next cell in current row with [SpacingConfiguration.horizontalUnrelatedGap]. Should not be used for last cell in a row
-   */
-  fun rightUnrelatedGap(): CellBuilder<T> {
-    rightGap = builder.spacing.horizontalUnrelatedGap
-    return this
-  }
-
-  fun comment(@NlsContexts.DetailedDescription comment: String,
-              maxLineLength: Int = ComponentPanelBuilder.MAX_COMMENT_WIDTH): CellBuilder<T> {
-    this.comment = ComponentPanelBuilder.createCommentComponent(comment, true, maxLineLength, true)
-    return this
-  }
-
-  private fun shouldSaveOnApply(): Boolean {
-    return !(applyIfEnabled && !viewComponent.isEnabled)
-  }
-
-  private fun onApply(callback: () -> Unit): CellBuilder<T> {
-    builder.applyCallbacks.getOrPut(component) { SmartList() }.add(callback)
-    return this
-  }
-
-  private fun onReset(callback: () -> Unit): CellBuilder<T> {
-    builder.resetCallbacks.getOrPut(component) { SmartList() }.add(callback)
-    return this
-  }
-
-  private fun onIsModified(callback: () -> Boolean): CellBuilder<T> {
-    builder.isModifiedCallbacks.getOrPut(component) { SmartList() }.add(callback)
-    return this
-  }
-
-  fun <V> bind(
-    componentGet: (T) -> V,
-    componentSet: (T, V) -> Unit,
-    modelBinding: PropertyBinding<V>
-  ): CellBuilder<T> {
-    onApply { if (shouldSaveOnApply()) modelBinding.set(componentGet(component)) }
-    onReset { componentSet(component, modelBinding.get()) }
-    onIsModified { shouldSaveOnApply() && componentGet(component) != modelBinding.get() }
-    return this
-  }
+  fun <V> bind(componentGet: (T) -> V, componentSet: (T, V) -> Unit, modelBinding: PropertyBinding<V>): CellBuilder<T>
 }
 
 fun <T : AbstractButton> CellBuilder<T>.bind(modelBinding: PropertyBinding<Boolean>): CellBuilder<T> {

platform/platform-impl/src/com/intellij/ui/dsl/CellBuilderBase.kt

@@ -0,0 +1,36 @@
+// Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.ui.dsl
+
+import com.intellij.openapi.ui.panel.ComponentPanelBuilder
+import com.intellij.openapi.util.NlsContexts
+import com.intellij.ui.dsl.gridLayout.HorizontalAlign
+import com.intellij.ui.dsl.gridLayout.VerticalAlign
+import org.jetbrains.annotations.ApiStatus
+import javax.swing.JComponent
+
+@DslMarker
+private annotation class CellBuilderMarker
+
+@ApiStatus.Experimental
+@CellBuilderMarker
+interface CellBuilderBase<T : CellBuilderBase<T>> {
+
+  val horizontalAlign: HorizontalAlign
+  val verticalAlign: VerticalAlign
+  val rightGap: Int
+  val comment: JComponent?
+
+  fun alignHorizontal(horizontalAlign: HorizontalAlign): CellBuilderBase<T>
+
+  fun alignVertical(verticalAlign: VerticalAlign): CellBuilderBase<T>
+
+  fun comment(@NlsContexts.DetailedDescription comment: String,
+              maxLineLength: Int = ComponentPanelBuilder.MAX_COMMENT_WIDTH): CellBuilderBase<T>
+
+  /**
+   * Separates next cell in current row with [SpacingConfiguration.horizontalUnrelatedGap].
+   * Should not be used for last cell in a row
+   */
+  fun rightUnrelatedGap(): CellBuilderBase<T>
+
+}

platform/platform-impl/src/com/intellij/ui/dsl/PanelBuilder.kt

@@ -1,112 +1,7 @@
 // Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.ui.dsl
 
-import com.intellij.openapi.diagnostic.Logger
-import com.intellij.openapi.ui.DialogPanel
-import com.intellij.ui.dsl.gridLayout.Gaps
-import com.intellij.ui.dsl.gridLayout.JBGridLayout
-import com.intellij.ui.dsl.gridLayout.builders.RowsGridBuilder
 import org.jetbrains.annotations.ApiStatus
-import org.jetbrains.annotations.Nls
-import javax.swing.*
-import javax.swing.text.JTextComponent
 
 @ApiStatus.Experimental
-class PanelBuilder {
-
-  companion object {
-    private val LOG = Logger.getInstance(PanelBuilder::class.java)
-
-    private val DEFAULT_VERTICAL_GAP_COMPONENTS = setOf(JTextComponent::class, AbstractButton::class, JSpinner::class, JLabel::class)
-  }
-
-  val spacing = createIntelliJSpacingConfiguration()
-
-  val applyCallbacks: MutableMap<JComponent?, MutableList<() -> Unit>> = linkedMapOf()
-  val resetCallbacks: MutableMap<JComponent?, MutableList<() -> Unit>> = linkedMapOf()
-  val isModifiedCallbacks: MutableMap<JComponent?, MutableList<() -> Boolean>> = linkedMapOf()
-
-  private val rows = mutableListOf<RowBuilder>()
-
-  fun row(@Nls label: String, init: RowBuilder.() -> Unit): RowBuilder {
-    return row(JLabel(label), init)
-  }
-
-  fun row(label: JLabel? = null, init: RowBuilder.() -> Unit): RowBuilder {
-    val result = RowBuilder(this, label)
-    result.init()
-    rows.add(result)
-    return result
-  }
-
-  internal fun build(): DialogPanel {
-    val result = DialogPanel(layout = JBGridLayout())
-    val columnsCount = rows.maxOf { it.cells.size }
-    val rowsGridBuilder = RowsGridBuilder(result)
-
-    for ((y, row) in rows.withIndex()) {
-      for ((x, cell) in row.cells.withIndex()) {
-        val width: Int
-        var rightGap = cell.rightGap
-        if (x == row.cells.size - 1) {
-          width = columnsCount - x
-          if (cell.rightGap > 0) {
-            LOG.warn("Right gap is set for last cell and will be ignored: rightGap = $rightGap")
-            rightGap = 0
-          }
-        }
-        else {
-          width = 1
-        }
-
-        val insets = cell.component.insets
-        val verticalGap = getDefaultVerticalGap(cell.component)
-        rowsGridBuilder.cell(cell.component, width = width, horizontalAlign = cell.horizontalAlign, verticalAlign = cell.verticalAlign,
-                             gaps = Gaps(top = verticalGap, bottom = verticalGap, right = rightGap),
-                             visualPaddings = Gaps(top = insets.top, left = insets.left, bottom = insets.bottom, right = insets.right))
-      }
-
-      rowsGridBuilder.row()
-      createCommentRow(rowsGridBuilder, row, columnsCount)
-    }
-
-    return result
-  }
-
-  /**
-   * Returns default top and bottom gap for [component]
-   */
-  private fun getDefaultVerticalGap(component: JComponent): Int {
-    return if (DEFAULT_VERTICAL_GAP_COMPONENTS.any { clazz -> clazz.isInstance(component) }) spacing.verticalComponentGap else 0
-  }
-
-  /**
-   * Appends comment (currently one comment for a row is supported, can be fixed later)
-   */
-  private fun createCommentRow(builder: RowsGridBuilder, row: RowBuilder, columnsCount: Int) {
-    for ((column, cell) in row.cells.withIndex()) {
-      cell.comment?.let {
-        createComment(builder, column, columnsCount, row.label != null, it, cell.viewComponent)
-        return
-      }
-    }
-  }
-
-  private fun createComment(builder: RowsGridBuilder,
-                            column: Int,
-                            columnsCount: Int,
-                            labeledRow: Boolean,
-                            comment: JComponent,
-                            anchorComponent: JComponent) {
-    if (labeledRow && column == 1) {
-      builder.cell(comment, width = columnsCount)
-    }
-    else {
-      val gaps = Gaps(left = if (anchorComponent is JToggleButton) spacing.horizontalIndent else 0,
-                      bottom = spacing.verticalCommentBottomGap)
-      builder.skip(column)
-      builder.cell(comment, columnsCount - column, gaps = gaps)
-    }
-    builder.row()
-  }
-}
+interface PanelBuilder: PanelBuilderBase, CellBuilderBase<PanelBuilder>

platform/platform-impl/src/com/intellij/ui/dsl/PanelBuilderBase.kt

@@ -0,0 +1,14 @@
+// Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.ui.dsl
+
+import org.jetbrains.annotations.ApiStatus
+import org.jetbrains.annotations.Nls
+import javax.swing.JLabel
+
+@ApiStatus.Experimental
+interface PanelBuilderBase {
+
+  fun row(@Nls label: String, init: RowBuilder.() -> Unit): RowBuilder
+
+  fun row(label: JLabel? = null, init: RowBuilder.() -> Unit): RowBuilder
+}

platform/platform-impl/src/com/intellij/ui/dsl/RowBuilder.kt

@@ -1,41 +1,26 @@
 // Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.ui.dsl
 
-import com.intellij.BundleBase
 import com.intellij.openapi.util.NlsContexts
 import com.intellij.ui.components.JBCheckBox
 import org.jetbrains.annotations.ApiStatus
 import java.awt.event.ActionEvent
 import javax.swing.JButton
 import javax.swing.JComponent
-import javax.swing.JLabel
 
 @DslMarker
 private annotation class RowBuilderMarker
 
 @ApiStatus.Experimental
 @RowBuilderMarker
-class RowBuilder(val builder: PanelBuilder, val label: JLabel?) {
+interface RowBuilder {
 
-  internal val cells = mutableListOf<CellBuilder<JComponent>>()
+  fun <T : JComponent> cell(component: T): CellBuilder<T>
 
-  init {
-    label?.let { cell(it) }
-  }
+  fun panel(init: PanelBuilder.() -> Unit): PanelBuilder
 
-  fun <T : JComponent> cell(component: T): CellBuilder<T> {
-    val result = CellBuilder(builder, component)
-    cells.add(result)
-    return result
-  }
+  fun checkBox(@NlsContexts.Checkbox text: String): CellBuilder<JBCheckBox>
 
-  fun checkBox(@NlsContexts.Checkbox text: String): CellBuilder<JBCheckBox> {
-    return cell(JBCheckBox(text))
-  }
+  fun button(@NlsContexts.Button text: String, actionListener: (event: ActionEvent) -> Unit): CellBuilder<JButton>
 
-  fun button(@NlsContexts.Button text: String, actionListener: (event: ActionEvent) -> Unit): CellBuilder<JButton> {
-    val button = JButton(BundleBase.replaceMnemonicAmpersand(text))
-    button.addActionListener(actionListener)
-    return cell(button)
-  }
 }

platform/platform-impl/src/com/intellij/ui/dsl/SpacingConfiguration.kt

@@ -1,7 +1,6 @@
 // Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
 package com.intellij.ui.dsl
 
-import com.intellij.util.ui.JBUI
 import org.jetbrains.annotations.ApiStatus
 
 @ApiStatus.Experimental
@@ -28,15 +27,3 @@ interface SpacingConfiguration {
   val verticalCommentBottomGap: Int
 
 }
-
-// https://jetbrains.github.io/ui/controls/input_field/#spacing
-@ApiStatus.Experimental
-fun createIntelliJSpacingConfiguration(): SpacingConfiguration {
-  return object : SpacingConfiguration {
-
-    override val horizontalUnrelatedGap = JBUI.scale(16)
-    override val horizontalIndent = JBUI.scale(20)
-    override val verticalComponentGap = JBUI.scale(6)
-    override val verticalCommentBottomGap = JBUI.scale(6)
-  }
-}

platform/platform-impl/src/com/intellij/ui/dsl/impl/CellBuilderBaseImpl.kt

@@ -0,0 +1,50 @@
+// Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.ui.dsl.impl
+
+import com.intellij.openapi.ui.panel.ComponentPanelBuilder
+import com.intellij.openapi.util.NlsContexts
+import com.intellij.ui.dsl.CellBuilderBase
+import com.intellij.ui.dsl.SpacingConfiguration
+import com.intellij.ui.dsl.gridLayout.HorizontalAlign
+import com.intellij.ui.dsl.gridLayout.VerticalAlign
+import org.jetbrains.annotations.ApiStatus
+import javax.swing.JComponent
+
+@ApiStatus.Experimental
+internal open class CellBuilderBaseImpl<T : CellBuilderBase<T>>(private val dialogPanelConfig: DialogPanelConfig) : CellBuilderBase<T> {
+
+  override var horizontalAlign = HorizontalAlign.LEFT
+    protected set
+
+  override var verticalAlign = VerticalAlign.CENTER
+    protected set
+
+  override var rightGap = 0
+    protected set
+
+  override var comment: JComponent? = null
+    protected set
+
+  override fun alignHorizontal(horizontalAlign: HorizontalAlign): CellBuilderBase<T> {
+    this.horizontalAlign = horizontalAlign
+    return this
+  }
+
+  override fun alignVertical(verticalAlign: VerticalAlign): CellBuilderBase<T> {
+    this.verticalAlign = verticalAlign
+    return this
+  }
+
+  override fun comment(@NlsContexts.DetailedDescription comment: String, maxLineLength: Int): CellBuilderBase<T> {
+    this.comment = ComponentPanelBuilder.createCommentComponent(comment, true, maxLineLength, true)
+    return this
+  }
+
+  /**
+   * Separates next cell in current row with [SpacingConfiguration.horizontalUnrelatedGap]. Should not be used for last cell in a row
+   */
+  override fun rightUnrelatedGap(): CellBuilderBase<T> {
+    rightGap = dialogPanelConfig.spacing.horizontalUnrelatedGap
+    return this
+  }
+}

platform/platform-impl/src/com/intellij/ui/dsl/impl/CellBuilderImpl.kt

@@ -0,0 +1,81 @@
+// Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.ui.dsl.impl
+
+import com.intellij.openapi.util.NlsContexts
+import com.intellij.ui.dsl.CellBuilder
+import com.intellij.ui.dsl.gridLayout.HorizontalAlign
+import com.intellij.ui.dsl.gridLayout.VerticalAlign
+import com.intellij.ui.layout.*
+import com.intellij.util.SmartList
+import org.jetbrains.annotations.ApiStatus
+import javax.swing.JComponent
+
+@ApiStatus.Experimental
+internal class CellBuilderImpl<T : JComponent>(
+  private val dialogPanelConfig: DialogPanelConfig,
+  val component: T,
+  val viewComponent: JComponent = component) : CellBuilderBaseImpl<CellBuilder<T>>(dialogPanelConfig), CellBuilder<T> {
+
+  private var applyIfEnabled = false
+
+  override fun alignHorizontal(horizontalAlign: HorizontalAlign): CellBuilder<T> {
+    super.alignHorizontal(horizontalAlign)
+    return this
+  }
+
+  override fun alignVertical(verticalAlign: VerticalAlign): CellBuilder<T> {
+    super.alignVertical(verticalAlign)
+    return this
+  }
+
+  override fun comment(@NlsContexts.DetailedDescription comment: String, maxLineLength: Int): CellBuilder<T> {
+    super.comment(comment, maxLineLength)
+    return this
+  }
+
+  override fun rightUnrelatedGap(): CellBuilder<T> {
+    super.rightUnrelatedGap()
+    return this
+  }
+
+  override fun applyToComponent(task: T.() -> Unit): CellBuilder<T> {
+    component.task()
+    return this
+  }
+
+  override fun enabled(isEnabled: Boolean): CellBuilder<T> {
+    viewComponent.isEnabled = isEnabled
+    return this
+  }
+
+  override fun applyIfEnabled(): CellBuilder<T> {
+    applyIfEnabled = true
+    return this
+  }
+
+  override fun <V> bind(componentGet: (T) -> V, componentSet: (T, V) -> Unit, modelBinding: PropertyBinding<V>): CellBuilder<T> {
+    onApply { if (shouldSaveOnApply()) modelBinding.set(componentGet(component)) }
+    onReset { componentSet(component, modelBinding.get()) }
+    onIsModified { shouldSaveOnApply() && componentGet(component) != modelBinding.get() }
+    return this
+  }
+
+  private fun shouldSaveOnApply(): Boolean {
+    return !(applyIfEnabled && !viewComponent.isEnabled)
+  }
+
+  private fun onApply(callback: () -> Unit): CellBuilder<T> {
+    dialogPanelConfig.applyCallbacks.getOrPut(component) { SmartList() }.add(callback)
+    return this
+  }
+
+  private fun onReset(callback: () -> Unit): CellBuilder<T> {
+    dialogPanelConfig.resetCallbacks.getOrPut(component) { SmartList() }.add(callback)
+    return this
+  }
+
+  private fun onIsModified(callback: () -> Boolean): CellBuilder<T> {
+    dialogPanelConfig.isModifiedCallbacks.getOrPut(component) { SmartList() }.add(callback)
+    return this
+  }
+}

platform/platform-impl/src/com/intellij/ui/dsl/impl/DialogPanelConfig.kt

@@ -0,0 +1,28 @@
+// Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.ui.dsl.impl
+
+import com.intellij.ui.dsl.SpacingConfiguration
+import com.intellij.util.ui.JBUI
+import org.jetbrains.annotations.ApiStatus
+import javax.swing.JComponent
+
+@ApiStatus.Experimental
+internal class DialogPanelConfig {
+
+  val spacing = createIntelliJSpacingConfiguration()
+
+  val applyCallbacks: MutableMap<JComponent?, MutableList<() -> Unit>> = linkedMapOf()
+  val resetCallbacks: MutableMap<JComponent?, MutableList<() -> Unit>> = linkedMapOf()
+  val isModifiedCallbacks: MutableMap<JComponent?, MutableList<() -> Boolean>> = linkedMapOf()
+}
+
+// https://jetbrains.github.io/ui/controls/input_field/#spacing
+private fun createIntelliJSpacingConfiguration(): SpacingConfiguration {
+  return object : SpacingConfiguration {
+
+    override val horizontalUnrelatedGap = JBUI.scale(16)
+    override val horizontalIndent = JBUI.scale(20)
+    override val verticalComponentGap = JBUI.scale(6)
+    override val verticalCommentBottomGap = JBUI.scale(6)
+  }
+}

platform/platform-impl/src/com/intellij/ui/dsl/impl/PanelBuilderImpl.kt

@@ -0,0 +1,141 @@
+// Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.ui.dsl.impl
+
+import com.intellij.openapi.diagnostic.Logger
+import com.intellij.openapi.ui.DialogPanel
+import com.intellij.openapi.util.NlsContexts
+import com.intellij.ui.dsl.CellBuilderBase
+import com.intellij.ui.dsl.PanelBuilder
+import com.intellij.ui.dsl.RowBuilder
+import com.intellij.ui.dsl.gridLayout.Gaps
+import com.intellij.ui.dsl.gridLayout.HorizontalAlign
+import com.intellij.ui.dsl.gridLayout.JBGrid
+import com.intellij.ui.dsl.gridLayout.VerticalAlign
+import com.intellij.ui.dsl.gridLayout.builders.RowsGridBuilder
+import org.jetbrains.annotations.ApiStatus
+import org.jetbrains.annotations.Nls
+import javax.swing.*
+import javax.swing.text.JTextComponent
+
+@ApiStatus.Experimental
+internal class PanelBuilderImpl(private val dialogPanelConfig: DialogPanelConfig) : CellBuilderBaseImpl<PanelBuilder>(
+  dialogPanelConfig), PanelBuilder {
+
+  companion object {
+    private val LOG = Logger.getInstance(PanelBuilderImpl::class.java)
+
+    private val DEFAULT_VERTICAL_GAP_COMPONENTS = setOf(JTextComponent::class, AbstractButton::class, JSpinner::class, JLabel::class)
+  }
+
+  private val rows = mutableListOf<RowBuilderImpl>()
+
+  override fun row(@Nls label: String, init: RowBuilder.() -> Unit): RowBuilder {
+    return row(JLabel(label), init)
+  }
+
+  override fun row(label: JLabel?, init: RowBuilder.() -> Unit): RowBuilder {
+    val result = RowBuilderImpl(dialogPanelConfig, label)
+    result.init()
+    rows.add(result)
+    return result
+  }
+
+  override fun alignHorizontal(horizontalAlign: HorizontalAlign): CellBuilderBase<PanelBuilder> {
+    super.alignHorizontal(horizontalAlign)
+    return this
+  }
+
+  override fun alignVertical(verticalAlign: VerticalAlign): CellBuilderBase<PanelBuilder> {
+    super.alignVertical(verticalAlign)
+    return this
+  }
+
+  override fun comment(@NlsContexts.DetailedDescription comment: String, maxLineLength: Int): CellBuilderBase<PanelBuilder> {
+    super.comment(comment, maxLineLength)
+    return this
+  }
+
+  override fun rightUnrelatedGap(): CellBuilderBase<PanelBuilder> {
+    super.rightUnrelatedGap()
+    return this
+  }
+
+  fun build(panel: DialogPanel, grid: JBGrid) {
+    val columnsCount = rows.maxOf { it.cells.size }
+    val rowsGridBuilder = RowsGridBuilder(panel, grid = grid)
+
+    for ((rowIndex, row) in rows.withIndex()) {
+      for ((cellIndex, cell) in row.cells.withIndex()) {
+        val width: Int
+        var rightGap = cell.rightGap
+        if (cellIndex == row.cells.size - 1) {
+          width = columnsCount - cellIndex
+          if (cell.rightGap > 0) {
+            LOG.warn("Right gap is set for last cell and will be ignored: rightGap = $rightGap")
+            rightGap = 0
+          }
+        }
+        else {
+          width = 1
+        }
+
+        // todo
+        if (cell is CellBuilderImpl<*>) {
+          val insets = cell.component.insets
+          val verticalGap = getDefaultVerticalGap(cell.component)
+          val gaps = Gaps(top = verticalGap, bottom = verticalGap, right = rightGap)
+          val visualPaddings = Gaps(top = insets.top, left = insets.left, bottom = insets.bottom, right = insets.right)
+          rowsGridBuilder.cell(cell.component, width = width, horizontalAlign = cell.horizontalAlign, verticalAlign = cell.verticalAlign,
+                               gaps = gaps,
+                               visualPaddings = visualPaddings)
+        }
+      }
+
+      rowsGridBuilder.row()
+      createCommentRow(rowsGridBuilder, row, columnsCount)
+    }
+  }
+
+  /**
+   * Returns default top and bottom gap for [component]
+   */
+  private fun getDefaultVerticalGap(component: JComponent): Int {
+    return if (DEFAULT_VERTICAL_GAP_COMPONENTS.any { clazz ->
+        clazz.isInstance(component)
+      }) dialogPanelConfig.spacing.verticalComponentGap
+    else 0
+  }
+
+  /**
+   * Appends comment (currently one comment for a row is supported, can be fixed later)
+   */
+  private fun createCommentRow(builder: RowsGridBuilder, row: RowBuilderImpl, columnsCount: Int) {
+    for ((column, cell) in row.cells.withIndex()) {
+      cell.comment?.let {
+        val additionalHorizontalIndent = if (cell is CellBuilderImpl<*> && cell.viewComponent is JToggleButton)
+          dialogPanelConfig.spacing.horizontalIndent
+        else
+          0
+        createComment(builder, column, columnsCount, row.label != null, it, additionalHorizontalIndent)
+        return
+      }
+    }
+  }
+
+  private fun createComment(builder: RowsGridBuilder,
+                            column: Int,
+                            columnsCount: Int,
+                            labeledRow: Boolean,
+                            comment: JComponent,
+                            additionalHorizontalIndent: Int) {
+    if (labeledRow && column == 1) {
+      builder.cell(comment, width = columnsCount)
+    }
+    else {
+      val gaps = Gaps(left = additionalHorizontalIndent, bottom = dialogPanelConfig.spacing.verticalCommentBottomGap)
+      builder.skip(column)
+      builder.cell(comment, columnsCount - column, gaps = gaps)
+    }
+    builder.row()
+  }
+}

platform/platform-impl/src/com/intellij/ui/dsl/impl/RowBuilderImpl.kt

@@ -0,0 +1,51 @@
+// Copyright 2000-2021 JetBrains s.r.o. and contributors. Use of this source code is governed by the Apache 2.0 license that can be found in the LICENSE file.
+package com.intellij.ui.dsl.impl
+
+import com.intellij.BundleBase
+import com.intellij.openapi.util.NlsContexts
+import com.intellij.ui.components.JBCheckBox
+import com.intellij.ui.dsl.CellBuilder
+import com.intellij.ui.dsl.CellBuilderBase
+import com.intellij.ui.dsl.PanelBuilder
+import com.intellij.ui.dsl.RowBuilder
+import org.jetbrains.annotations.ApiStatus
+import java.awt.event.ActionEvent
+import javax.swing.JButton
+import javax.swing.JComponent
+import javax.swing.JLabel
+
+@ApiStatus.Experimental
+internal class RowBuilderImpl(private val dialogPanelConfig: DialogPanelConfig, val label: JLabel?) : RowBuilder {
+
+  val cells: List<CellBuilderBase<*>>
+    get() = _cells
+
+  private val _cells = mutableListOf<CellBuilderBase<*>>()
+
+  init {
+    label?.let { cell(it) }
+  }
+
+  override fun <T : JComponent> cell(component: T): CellBuilder<T> {
+    val result = CellBuilderImpl(dialogPanelConfig, component)
+    _cells.add(result)
+    return result
+  }
+
+  override fun panel(init: PanelBuilder.() -> Unit): PanelBuilder {
+    val result = PanelBuilderImpl(dialogPanelConfig)
+    result.init()
+    _cells.add(result)
+    return result
+  }
+
+  override fun checkBox(@NlsContexts.Checkbox text: String): CellBuilder<JBCheckBox> {
+    return cell(JBCheckBox(text))
+  }
+
+  override fun button(@NlsContexts.Button text: String, actionListener: (event: ActionEvent) -> Unit): CellBuilder<JButton> {
+    val button = JButton(BundleBase.replaceMnemonicAmpersand(text))
+    button.addActionListener(actionListener)
+    return cell(button)
+  }
+}

platform/platform-impl/src/com/intellij/ui/dsl/panel.kt

@@ -2,26 +2,38 @@
 package com.intellij.ui.dsl
 
 import com.intellij.openapi.ui.DialogPanel
+import com.intellij.ui.dsl.gridLayout.JBGridLayout
+import com.intellij.ui.dsl.impl.DialogPanelConfig
+import com.intellij.ui.dsl.impl.PanelBuilderImpl
 import org.jetbrains.annotations.ApiStatus
 
+/*
+todo
+remove first/last gaps
+panel in ShelfProjectConfigurable
+*/
+
 @ApiStatus.Experimental
-fun panel(init: PanelBuilder.() -> Unit): DialogPanel {
-  val builder = PanelBuilder()
+fun panel(init: PanelBuilderBase.() -> Unit): DialogPanel { // Dialog panel content supports only PanelBuilderBase, no CellBuilderBase
+  val dialogPanelConfig = DialogPanelConfig()
+  val builder = PanelBuilderImpl(dialogPanelConfig)
   builder.init()
 
-  val panel = builder.build()
-  initPanel(builder, panel)
-  return panel
+  val layout = JBGridLayout()
+  val result = DialogPanel(layout = layout)
+  builder.build(result, layout.rootGrid)
+  initPanel(dialogPanelConfig, result)
+  return result
 }
 
-private fun initPanel(builder: PanelBuilder, panel: DialogPanel) {
+private fun initPanel(dialogPanelConfig: DialogPanelConfig, panel: DialogPanel) {
   /* todo
   panel.preferredFocusedComponent = builder.builder.preferredFocusedComponent
   panel.validateCallbacks = builder.builder.validateCallbacks
   panel.componentValidateCallbacks = builder.builder.componentValidateCallbacks
   panel.customValidationRequestors = builder.builder.customValidationRequestors
   */
-  panel.applyCallbacks = builder.applyCallbacks
-  panel.resetCallbacks = builder.resetCallbacks
-  panel.isModifiedCallbacks = builder.isModifiedCallbacks
+  panel.applyCallbacks = dialogPanelConfig.applyCallbacks
+  panel.resetCallbacks = dialogPanelConfig.resetCallbacks
+  panel.isModifiedCallbacks = dialogPanelConfig.isModifiedCallbacks
 }