Ask wether to merge

BlockPi/src/msg/en.js

@@ -40,5 +40,6 @@ var MSG = {
   typeError: "You are not loading a XML file!",
   hashError: "Sorry, '%1' doesn't correspond with any saved program.",
   xmlError: "Could not load your saved file. Perhaps it was created with a different version of Blockly?",
-  badXml: "Error parsing XML:\n%1\n\nSelect 'OK' to abandon your changes or 'Cancel' to further edit the XML."
+  badXml: "Error parsing XML:\n%1\n\nSelect 'OK' to abandon your changes or 'Cancel' to further edit the XML.",
+  merge: "Shall we merge the existing blocks with the file you are loading?"
 };

BlockPi/src/msg/zh-hans.js

@@ -40,5 +40,6 @@ var MSG = {
   hashError: "对不起，没有任何已保存的程序对应'%1' 。",
   typeError: "您载入的不是XML文件！",
   xmlError: "无法载入您保存的文件。您是否使用其他版本的Blockly创建该文件的？",
-  badXml: "XML解析错误：\n%1\n\n选择“确定”以取消您对XML的修改，或选择“取消”以继续编辑XML。"
+  badXml: "XML解析错误：\n%1\n\n选择“确定”以取消您对XML的修改，或选择“取消”以继续编辑XML。",
+  merge: "是否将要载入的程序与现有积木块合并？"  
 };

BlockPi/src/msg/zh-hant.js

@@ -36,9 +36,10 @@ var MSG = {
   textVariable: "文字",
   deviceVariable: "設備",
   httpRequestError: "命令出現錯誤。",
-  linkAlert: "透過此連結分享您的積木組：\n\n%1",  
+  linkAlert: "透過此連結分享您的積木組：\n\n%1",
   typeError: "您載入的不是XML檔案！",
   hashError: "對不起，「%1」並未對應任何已保存的程式。",
   xmlError: "未能載入您保存的檔案。或許它是由其他版本的Blockly創建？",
-  badXml: "解析 XML 時出現錯誤：\n%1\n\n選擇'確定'以放棄您的更改，或選擇'取消'以進一步編輯 XML。"
+  badXml: "解析 XML 時出現錯誤：\n%1\n\n選擇'確定'以放棄您的更改，或選擇'取消'以進一步編輯 XML。",
+  merge: "是否將要載入的檔案與現有積木合併？"
 };

BlockPi/src/script/storage.js

@@ -63,9 +63,10 @@ BlocklyStorage.loadXml_ = function(xml, workspace) {
     BlocklyStorage.alert(BlocklyStorage.XML_ERROR + '\nXML: ' + xml);
     return;
   }
-  // Clear the workspace to avoid merge.
-  workspace.clear();
-  Blockly.Xml.domToWorkspace(xml, workspace);
+  // Ask whether to merge or override.
+  Blockly.confirm(MSG['merge'], (merge) => {
+    merge ? Blockly.Xml.appendDomToWorkspace(xml, workspace) : Blockly.Xml.clearWorkspaceAndLoadFromXml(xml, workspace);
+  })
 };
 
 /**