Patent ID: 8531687

Claim:
An image formation device, comprising: a display unit capable of displaying various types of information; a screen controller for controlling switching of a display screen to be displayed on said display unit; a hardware section for executing a specific function; a system controller for controlling said hardware section; and an application section for executing said specific function by putting said hardware section into operation through said system controller, and for creating a display screen relating to said specific function, said application section including a standard application section that executes standard functions installed in advance, and an extension application section that executes extension functions which are additionally implemented, and when said system controller detects the occurrence of an event in said hardware section with said display screen created in said standard application section being displayed on said display unit, said screen controller determines whether or not switching of a display screen to be displayed on said display unit should be made said detected event, and when said system controller detects the occurrence of said event in said hardware section with said display screen created in said extension application section being displayed on said display unit, said screen controller requests said extension application section to determine whether or not switching of the display screen to be displayed on said display unit should be made, and controls switching of the display screen to be displayed on said display unit based on a result of the determination made by said extension application section, wherein said event is an error generated in said hardware section; and when said system controller detects generation of said error with said display screen created in said extension application section being displayed on said display unit, said screen controller determines the level of said error, and switches a display screen to be displayed on said display unit to an error screen when said level is higher than a predetermined level, while requesting said extension application section to determine whether or not switching of a display screen to be displayed on said display unit should be made when said level is lower than said predetermined level.