O’zaro ta’sirli interfeysni loyihalashda hisobga olinishi kerak bo‘lgan operatorning asosiy xususiyatlari

2.9 Distributed User Interfaces
When considering user access in multi-device environments we can identify various possibilities:

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  Accessing applications through different devices at different times (one device at each time);
  
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  Distributed user interfaces: application logic receiving input from multiple devices;
  
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  Moving objects across interactive devices (e.g. through pick-and-drop (Rekimoto, 87));
  
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  Migratory user interfaces: device change, interface migration with state preservation.
  

Distributed UIs and migratory UIs are two independent concepts, indeed there may exist distributed UIs which are also able to migrate, but there are also only distributed user interfaces (which do not migrate at all), or migratory UIs that are not distributed across multiple devices.
Multi-device support is emerging in various environments. OS X Lion Resume (footnote 3) provides a
'Resume' feature, which lets users pick up where they left off their applications, along with their user interfaces. Chrome-to-phone (footnote 4) enables users to send links from their Chrome desktop browser to App on their Android device. Chrome-to-mobile (footnote 5) sends pages from your computer’s Chrome browser to the Chrome browser running on your mobile device. Firefox (footnote 6)
synchronizes bookmarks, tabs, and web history between desktop and mobile Firefox clients.
At research level, Myngle (Sohn et al., 2011) provides a unified Web history from multiple personal devices, and allows users to filter their history based on high-level categories.
When considering specifically distributed user interfaces, it is important to note that there are three types of information important to specify (Frosini et al., 2013): what interface parts have to be distributed; whether to enable input on such parts; target device(s), which should receive the distributed parts (they can be identified by device types, IDs, roles associated with devices).
Generally speaking the distribution can be defined in different ways:

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  In the description of the interactive application with the initial application specification (design-time);
  
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  Distribution defined through the handlers of the distribution events indicated in the interactive application specification (design-time definition + run-time execution);
  
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  Distribution obtained through dynamic customization tools (completely run-time), which allow users to obtain distributions that were not planned at design time.
  

An example of distribution obtained through dynamic customization tools is presented in Manca and Paterno (2013). It uses the CARE properties to specify distribution in a MARIA-based description. When the application is generated it is still possible for the end user to customise its distribution across various devices through an interactive tool in order to address needs not foreseen at design time. Figure 16 shows an example: at the beginning the user interface is completely assigned to a mobile device; then through the interactive customization tool some elements are assigned to the large screen and others are redundant across the two devices.

Figure 2.16: Example of dynamic user interface distribution