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The DWG Expert uses another class BlockLibraryView.java to construct a widget that can be used to show all available blocks. The widget is a common Java class, the RecyclerView. The block library view processes all data from the block library BlockLibrary.java like the block name and the thumbnail. The final user action will happen on setOnClickListener() that is connected with a custom handler in setOnDoInsertHandler(). When the handler is triggered the block insertion is initiated with a command sequence using runCommand().
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