Sync Lines Between Panels When Possible

Not all users would want this so it's controlled by a menu item.

src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/KotlinExplorer.kt

@@ -37,6 +37,7 @@ import androidx.compose.ui.input.key.Key.Companion.L
 import androidx.compose.ui.input.key.Key.Companion.O
 import androidx.compose.ui.input.key.Key.Companion.P
 import androidx.compose.ui.input.key.Key.Companion.R
+import androidx.compose.ui.input.key.Key.Companion.S
 import androidx.compose.ui.text.font.FontFamily
 import androidx.compose.ui.text.style.TextAlign.Companion.Center
 import androidx.compose.ui.unit.DpSize
@@ -131,17 +132,22 @@ private class UiState(val explorerState: ExplorerState, window: ComposeWindow) {
         }
     }
 
-    val sourceTextArea = sourceTextArea(focusTracker, explorerState).apply { requestFocusInWindow() }
-    val byteCodeTextArea = byteCodeTextArea(explorerState, focusTracker)
-    val dexTextArea = dexTextArea(explorerState, focusTracker)
+    val sourceTextArea: SourceTextArea = sourceTextArea(focusTracker, explorerState).apply { requestFocusInWindow() }
+    val byteCodeTextArea = byteCodeTextArea(explorerState, focusTracker, sourceTextArea)
+    val dexTextArea = dexTextArea(explorerState, focusTracker, sourceTextArea)
     val oatTextArea = oatTextArea(explorerState, focusTracker)
+
     val codeTextAreas = listOf(byteCodeTextArea, dexTextArea, oatTextArea)
 
     val findDialog = FindDialog(window, searchListener).apply { searchContext.searchWrap = true }
     var showSettings by DialogState(!explorerState.toolPaths.isValid)
 
     val updatePresentationMode: (Boolean) -> Unit = {
-        listOf(dexTextArea, oatTextArea).forEach { area -> area.presentationMode = it }
+        listOf(byteCodeTextArea, dexTextArea, oatTextArea).forEach { area -> area.presentationMode = it }
+    }
+    val updateSyncLinesEnabled: (Boolean) -> Unit = {
+        listOf(byteCodeTextArea, dexTextArea).forEach { area -> area.isSyncLinesEnabled = it }
+        sourceTextArea.isSyncLinesEnabled = it
     }
 
     val updateShowLineNumbers: (Boolean) -> Unit = {
@@ -169,6 +175,8 @@ private fun FrameWindowScope.KotlinExplorer(
 ) {
     val uiState = remember { UiState(explorerState, window) }
 
+    uiState.sourceTextArea.addCodeTextAreas(uiState.byteCodeTextArea, uiState.dexTextArea)
+
     val sourcePanel: @Composable () -> Unit =
         { SourcePanel(uiState.sourceTextArea, explorerState, uiState.showSettings) }
     val byteCodePanel: @Composable () -> Unit =
@@ -193,6 +201,7 @@ private fun FrameWindowScope.KotlinExplorer(
         { panels = explorerState.getPanels(sourcePanel, byteCodePanel, dexPanel, oatPanel) },
         uiState.updateShowLineNumbers,
         uiState.updatePresentationMode,
+        uiState.updateSyncLinesEnabled,
     )
 
     if (uiState.showSettings) {
@@ -322,30 +331,31 @@ private fun Title(text: String) {
     )
 }
 
-private fun sourceTextArea(focusTracker: FocusListener, explorerState: ExplorerState): RSyntaxTextArea {
-    return RSyntaxTextArea().apply {
+private fun sourceTextArea(focusTracker: FocusListener, explorerState: ExplorerState): SourceTextArea {
+    return SourceTextArea(explorerState.syncLines).apply {
         configureSyntaxTextArea(SyntaxConstants.SYNTAX_STYLE_KOTLIN, focusTracker)
         SwingUtilities.invokeLater { requestFocusInWindow() }
         document.addDocumentListener(DocumentChangeListener { explorerState.sourceCode = text })
     }
 }
 
-private fun byteCodeTextArea(state: ExplorerState, focusTracker: FocusListener) =
-    codeTextArea(state, focusTracker)
+private fun byteCodeTextArea(state: ExplorerState, focusTracker: FocusListener, sourceTextArea: SourceTextArea) =
+    codeTextArea(state, focusTracker, sourceTextArea = sourceTextArea)
 
-private fun dexTextArea(state: ExplorerState, focusTracker: FocusListener) =
-    codeTextArea(state, focusTracker)
+private fun dexTextArea(state: ExplorerState, focusTracker: FocusListener, sourceTextArea: SourceTextArea) =
+    codeTextArea(state, focusTracker, sourceTextArea = sourceTextArea)
 
 private fun oatTextArea(state: ExplorerState, focusTracker: FocusListener) =
     codeTextArea(state, focusTracker, hasLineNumbers = false)
 
 private fun codeTextArea(
     state: ExplorerState,
     focusTracker: FocusListener,
-    hasLineNumbers: Boolean = true
+    hasLineNumbers: Boolean = true,
+    sourceTextArea: SourceTextArea? = null,
 ): CodeTextArea {
     val codeStyle = CodeStyle(state.indent, state.showLineNumbers && hasLineNumbers, state.lineNumberWidth)
-    return CodeTextArea(state.presentationMode, codeStyle).apply {
+    return CodeTextArea(state.presentationMode, codeStyle, state.syncLines, sourceTextArea).apply {
         configureSyntaxTextArea(SyntaxConstants.SYNTAX_STYLE_NONE, focusTracker)
     }
 }
@@ -365,6 +375,7 @@ private fun FrameWindowScope.MainMenu(
     onPanelsUpdated: () -> Unit,
     onShowLineNumberChanged: (Boolean) -> Unit,
     onPresentationModeChanged: (Boolean) -> Unit,
+    onSyncLinesChanged: (Boolean) -> Unit,
 ) {
     val scope = rememberCoroutineScope()
 
@@ -409,6 +420,7 @@ private fun FrameWindowScope.MainMenu(
             MenuCheckboxItem("Show Line Numbers", CtrlShift(L), explorerState::showLineNumbers) {
                 onShowLineNumberChanged(it)
             }
+            MenuCheckboxItem("Sync lines", Ctrl(S), explorerState::syncLines, onSyncLinesChanged)
             Separator()
             MenuCheckboxItem("Show Logs", Ctrl(L), explorerState::showLogs)
             Separator()
@@ -442,7 +454,6 @@ private fun RSyntaxTextArea.configureSyntaxTextArea(syntaxStyle: String, focusTr
     tabsEmulated = true
     tabSize = 4
     applyTheme(this)
-    currentLineHighlightColor = java.awt.Color.decode("#F5F8FF")
     addFocusListener(focusTracker)
 }
 
@@ -526,4 +537,4 @@ private fun ExplorerState.setWindowState(windowState: WindowState) {
 private fun CodeStyle.withSettings(indent: Int, lineNumberWidth: Int) =
     copy(indent = indent, lineNumberWidth = lineNumberWidth)
 
-private fun CodeStyle.withShowLineNumbers(value: Boolean) = copy(showLineNumbers = value)
+private fun CodeStyle.withShowLineNumbers(value: Boolean) = copy(showLineNumbers = value)

src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/SourceTextArea.kt

@@ -0,0 +1,49 @@
+/*
+ * Copyright 2024 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package dev.romainguy.kotlin.explorer
+
+import dev.romainguy.kotlin.explorer.code.CodeTextArea
+import org.fife.ui.rsyntaxtextarea.RSyntaxTextArea
+import java.awt.event.MouseAdapter
+import java.awt.event.MouseEvent
+
+class SourceTextArea(var isSyncLinesEnabled: Boolean) : RSyntaxTextArea() {
+    private val codeTextAreas = mutableListOf<CodeTextArea>()
+
+    init {
+        addMouseListener(object : MouseAdapter() {
+            override fun mouseClicked(event: MouseEvent) {
+                if (isSyncLinesEnabled) {
+                    codeTextAreas.forEach {
+                        it.gotoSourceLine(getLineOfOffset(viewToModel2D(event.point)))
+                    }
+                }
+            }
+        })
+    }
+
+    fun addCodeTextAreas(vararg codeTextAreas: CodeTextArea) {
+        this.codeTextAreas.addAll(codeTextAreas)
+    }
+
+    fun gotoLine(src: CodeTextArea, line: Int) {
+        caretPosition = getLineStartOffset(line.coerceIn(0 until lineCount))
+        centerCaretInView()
+        // Sync other `CodeTextArea` to same line as the `src` sent
+        codeTextAreas.filter { it !== src }.forEach { it.gotoSourceLine(line) }
+    }
+}

src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/State.kt

@@ -57,6 +57,7 @@ class ExplorerState {
     var showDex by BooleanState(ShowDex, true)
     var showOat by BooleanState(ShowOat, true)
     var showLogs by mutableStateOf(false)
+    var syncLines by mutableStateOf(false)
     var lineNumberWidth by IntState(LineNumberWidth, 4)
     var indent by IntState(Indent, 4)
     var sourceCode: String = readSourceCode(toolPaths)

src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/SwingPanel.kt → src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/Swing.kt

@@ -31,7 +31,10 @@ import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.toComposeImageBitmap
 import java.awt.Component
 import java.awt.GraphicsEnvironment
+import java.awt.Point
 import java.awt.image.BufferedImage
+import javax.swing.JTextArea
+import javax.swing.JViewport
 
 /**
  * A [SwingPanel] that supports a Dialog rendered over it
@@ -69,6 +72,12 @@ fun <T : Component> DialogSupportingSwingPanel(
     }
 }
 
+fun JTextArea.centerCaretInView() {
+    val viewport = parent as? JViewport ?: return
+    val linePos = modelToView2D(caretPosition).bounds.centerY.toInt()
+    viewport.viewPosition = Point(0, maxOf(0, linePos - viewport.height / 2))
+}
+
 private fun Component.getScreenShot(): BufferedImage? {
     if (width == 0 || height == 0) {
         return null

src/jvmMain/kotlin/dev/romainguy/kotlin/explorer/code/CodeTextArea.kt

@@ -16,23 +16,27 @@
 
 package dev.romainguy.kotlin.explorer.code
 
+import dev.romainguy.kotlin.explorer.SourceTextArea
+import dev.romainguy.kotlin.explorer.centerCaretInView
 import dev.romainguy.kotlin.explorer.code.CodeContent.*
 import org.fife.ui.rsyntaxtextarea.RSyntaxTextArea
 import java.awt.BasicStroke
 import java.awt.Graphics
 import java.awt.Graphics2D
 import java.awt.RenderingHints
+import java.awt.event.MouseAdapter
+import java.awt.event.MouseEvent
 import java.awt.geom.GeneralPath
 import javax.swing.event.CaretEvent
-import javax.swing.event.CaretListener
 
-open class CodeTextArea(
+class CodeTextArea(
     presentationMode: Boolean = false,
     codeStyle: CodeStyle,
+    var isSyncLinesEnabled: Boolean,
+    private val sourceTextArea: SourceTextArea?,
 ) : RSyntaxTextArea() {
     private var code: Code? = null
     private var jumpOffsets: JumpOffsets? = null
-
     private var content: CodeContent = Empty
 
     var presentationMode = presentationMode
@@ -52,9 +56,31 @@ open class CodeTextArea(
 
     init {
         addCaretListener(::caretUpdate)
+
+        if (sourceTextArea != null) {
+            addMouseListener(object : MouseAdapter() {
+                override fun mouseClicked(event: MouseEvent) {
+                    println(size)
+                    val codeLine = getLineOfOffset(viewToModel2D(event.point))
+                    val line = code?.getSourceLine(codeLine) ?: return
+                    sourceTextArea.gotoLine(this@CodeTextArea, line - 1)
+                }
+            })
+        }
     }
 
 
+    fun setContent(value: CodeContent) {
+        content = value
+        updateContent()
+    }
+
+    fun gotoSourceLine(sourceLine: Int) {
+        val line = code?.getCodeLine(sourceLine + 1) ?: return
+        caretPosition = getLineStartOffset(line.coerceIn(0 until lineCount))
+        centerCaretInView()
+    }
+
     private fun updatePreservingCaretLine() {
         val line = getLineOfOffset(caretPosition)
         val oldText = text
@@ -65,11 +91,6 @@ open class CodeTextArea(
         }
     }
 
-    fun setContent(value: CodeContent) {
-        content = value
-        updateContent()
-    }
-
     private fun updateContent() {
         val position = caretPosition
         code = null
@@ -86,10 +107,6 @@ open class CodeTextArea(
         caretPosition = minOf(position, document.length)
     }
 
-    final override fun addCaretListener(listener: CaretListener?) {
-        super.addCaretListener(listener)
-    }
-
     override fun paintComponent(g: Graphics?) {
         super.paintComponent(g)
         jumpOffsets?.let { jump ->

src/jvmMain/resources/themes/kotlin_explorer.xml

@@ -6,7 +6,7 @@
    <background color="ffffff" />
    <caret color="000000" />
    <selection fg="ffffff" bg="526da5" />
-   <currentLineHighlight color="f5f8fe" fade="false" />
+   <currentLineHighlight color="f2f6fe" fade="false" />
    <marginLine fg="b0b4b9" />
    <markAllHighlight color="edebfc" />
    <markOccurrencesHighlight color="edebfc" border="false" />