Creating buttons in google docs spreadsheet like EXCEL

Question

My question is quite simple but I can't figure it out. How can I create buttons in google docs spreadsheet which can be seen when logged in. I want to initialize the script upon logging into the google docs rather than going to load manually. Is there a way to do that? Also I couldn't find the nice tutorial which gives the intermediate knowledge about the google-docs function. All I could find was this simple tutorial. Another question is: Can the python script as provided by google-docs be saved and executed in google-docs itself? If it could, it can provide more functionality than simple google-functions. I am completely newbie to google docs so please bear with me.

Solution

You can create some UI elements using Google Apps Script.

https://developers.google.com/apps-script/guide_user_interfaces

Apps Script is javascript-like script that runs SERVER side, in google land. It has access to various services and google document model. But is otherwise restricted from many things that you'd think javascript can do. This is the root of most of its limitations. You can enable a script to load on start-up and hook into related events.

While there is Python and Java API to access Google Docs and their content, there is no way to to create the UI elements outside of Apps Script and the related UI Designer: http://googleappsdeveloper.blogspot.com/2011/06/building-ui-in-apps-script-just-got.html