From 7ae377d3e99a5515cd89ddb6675ff2b84c232f3b Mon Sep 17 00:00:00 2001
From: Cristian Maglie <c.maglie@arduino.cc>
Date: Mon, 20 Jan 2020 17:04:04 +0100
Subject: [PATCH] Do not clear serial monitor when disabled for upload
 (@PaulStoffregen)

Fix #9234
---
 .../processing/app/AbstractTextMonitor.java   | 25 ++++++++++++++++---
 app/src/processing/app/SerialMonitor.java     |  1 -
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/app/src/processing/app/AbstractTextMonitor.java b/app/src/processing/app/AbstractTextMonitor.java
index 4e35d4e44..733bae41b 100644
--- a/app/src/processing/app/AbstractTextMonitor.java
+++ b/app/src/processing/app/AbstractTextMonitor.java
@@ -3,6 +3,7 @@ package processing.app;
 import static processing.app.I18n.tr;
 
 import java.awt.BorderLayout;
+import java.awt.Color;
 import java.awt.Container;
 import java.awt.Dimension;
 import java.awt.Font;
@@ -170,9 +171,27 @@ public abstract class AbstractTextMonitor extends AbstractMonitor {
   }
 
   @Override
-  protected void onEnableWindow(boolean enable)
-  {
-    textArea.setEnabled(enable);
+  protected void onEnableWindow(boolean enable) {
+    Thread.dumpStack();
+    System.out.println("onEnableWindow " + enable);
+    // never actually disable textArea, so people can
+    // still select & copy text, even when the port
+    // is closed or disconnected
+    textArea.setEnabled(true);
+    if (enable) {
+      // setting these to null for system default
+      // gives a wrong gray background on Windows
+      // so assume black text on white background
+      textArea.setForeground(Color.BLACK);
+      textArea.setBackground(Color.WHITE);
+    } else {
+      // In theory, UIManager.getDefaults() should
+      // give us the system's colors for disabled
+      // windows.  But it doesn't seem to work.  :(
+      textArea.setForeground(new Color(64, 64, 64));
+      textArea.setBackground(new Color(238, 238, 238));
+    }
+    textArea.invalidate();
     clearButton.setEnabled(enable);
     scrollPane.setEnabled(enable);
     textField.setEnabled(enable);
diff --git a/app/src/processing/app/SerialMonitor.java b/app/src/processing/app/SerialMonitor.java
index acdfc9cb9..9af95d8d4 100644
--- a/app/src/processing/app/SerialMonitor.java
+++ b/app/src/processing/app/SerialMonitor.java
@@ -142,7 +142,6 @@ public class SerialMonitor extends AbstractTextMonitor {
       int[] location = getPlacement();
       String locationStr = PApplet.join(PApplet.str(location), ",");
       PreferencesData.set("last.serial.location", locationStr);
-      textArea.setText("");
       serial.dispose();
       serial = null;
     }