prevent Export with examples and untitled/unsaved sketches

build/shared/lib/languages/PDE.properties

@@ -217,6 +217,10 @@ export.full_screen = Full Screen
 export.embed_java = Embed Java
 export.embed_java.for = Embed Java for
 export.code_signing = Code Signing
+export.messages.is_read_only = Sketch is Read-Only
+export.messages.is_read_only.description = Some files are marked "read-only", so you will\nneed to re-save the sketch in another location,\nand try again.
+export.messages.cannot_export = Cannot Export
+export.messages.cannot_export.description = You cannot export a sketch that has not been saved.
 
 # Find (Frame)
 find = Find

java/src/processing/mode/java/JavaEditor.java

@@ -1096,6 +1096,20 @@ public class JavaEditor extends Editor {
    * <A HREF="http://dev.processing.org/bugs/show_bug.cgi?id=157">Bug 157</A>
    */
   protected boolean handleExportCheckModified() {
+    if (sketch.isReadOnly()) {
+      // if the files are read-only, need to first do a "save as".
+      Base.showMessage(Language.text("export.messages.is_read_only"),
+                       Language.text("export.messages.is_read_only.description"));
+      return false;
+    }
+
+    // don't allow if untitled
+    if (sketch.isUntitled()) {
+      Base.showMessage(Language.text("export.messages.cannot_export"),
+                       Language.text("export.messages.cannot_export.description"));
+      return false;
+    }
+
     if (sketch.isModified()) {
       Object[] options = { Language.text("prompt.ok"), Language.text("prompt.cancel") };
       int result = JOptionPane.showOptionDialog(this,

todo.txt

@@ -5,8 +5,7 @@ X create sketchbook subfolders on startup
 X   https://github.com/processing/processing/issues/3548
 X save export settings to preferences
 X disable Export button when no platforms selected
-_ export allowed with untitled sketches
-_   also with examples?
+X prevent Export with examples and untitled/unsaved sketches
 
 
 earlier/cleaning