Column class was created to be able modify faster the settings of field catalog at any place and time. Each field of field catalog has it set method with only one parameter IV_VALUE which type is equal ...
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ZCL_FALV_LAYOUT - layout class
ZCL_FALV_COLUMN - column (fcat) class
ZCL_FALV_DYNAMIC_STATUS - dynamic GUI status for full screen display
Function Group
ZFALV - screens, ...