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Making edit buttons just above cursor allows user to select an editing tool faster. It works especially well if the user is constantly switching editing tools. On the other hand, it may get tedious when the user is only using highlighting, and has to select the highlight tool every time after selecting text, which results in one more click per highlighting action. Making the most recent selected tool last until explicitly cancelled (by right click, for example) may help, but learnability-wise, the knowledge of 'right click to cancel current active tool' needs to be learned somehow.
Safety:
Design 2
This design is called the Notebook. Just as the name suggests, the design is based on the model of a notebook. The user cannot directly annotate on top of a webpage. Instead, a frame imitating a note page is attached to each webpage and the user can only change the content of this frame.
The user can perform two types of actions to any section of the webpage: copy and annotation. Both types will be demonstrated in the storyboard below. The result of each action (e.g., a copied picture or a note) will be added to the end of the note page. In the end, the note page can be visualized as a list of these results. When the user save his work, the webpage and the note page are saved together in our server.
Multiple users are allowed to collaboratively annotate the same webpage. The UI for this "collaborative editing mode" is almost identical to the "private editing mode" from before. The only difference now is that the user can see a colored circle beside each result in the note page. Each color corresponds to a unique user, the one responsible for the marked results. This way all users sharing the annotated webpage can be identified.
This design is called the Notebook. Just as the name suggests, the design is based on the model of a notebook. The user cannot directly annotate on top of a webpage. Instead, a frame imitating a note page is attached to each webpage and the user can only change the content of this frame.
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3. On the other hand, there is no built-in mechanism to prevent a user from deleting another user's result.
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