{"id":5168,"date":"2022-07-10T15:57:43","date_gmt":"2022-07-10T13:57:43","guid":{"rendered":"https:\/\/store.algosyntax.com\/?post_type=asx-lms-tutorial-cpt&p=5168"},"modified":"2026-03-09T21:55:05","modified_gmt":"2026-03-09T19:55:05","slug":"ue5-delegate-params-vs-payload-data","status":"publish","type":"asx-lms-tutorial-cpt","link":"https:\/\/store.algosyntax.com\/tutorials\/unreal-engine\/ue5-delegate-params-vs-payload-data\/","title":{"rendered":"UE5 Delegate Parameters vs Payload Data"},"content":{"rendered":"\t\t
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You may be wondering what’s the difference between UE5 Delegate Parameters and Payload Data as described in the Delegate documentation.<\/a>

Jump to the “Payload Data Example Use Case<\/strong><\/a>” section for an explanation by example if you prefer examples.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t

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The Callback Function Signature<\/h2>\t\t\t\t<\/div>\n\t\t\t\t
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The main difference between Payload Data and Parameters has to do with the binding function’s signature.<\/p>

The binding function\/callback<\/strong> signature<\/strong> has to match our delegate parameters<\/strong> PLUS<\/strong> desired extra parameters(payload data<\/strong>).<\/p>

\u00a0<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t

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Delegate Parameters<\/h3>\t\t\t\t<\/div>\n\t\t\t\t
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  • Required in EVERY<\/strong> callback function that wishes to bind to our delegate.<\/li>
  • Defined when delegate is created with DECLARE_DELEGATE or any similar macro.<\/li>
  • If you want every Bound function to receive data\/argument as part of it’s signature, you include it as a delegate Parameter.<\/li><\/ul>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t
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    Delegate Payload Data<\/h3>\t\t\t\t<\/div>\n\t\t\t\t
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    • Required ONLY IN<\/strong> callback functions that wish to receive extra<\/strong> parameters, in addition to the required parameters above,\u00a0 from our delegate when it broadcasts\/executes.<\/li>
    • Defined when delegate is bound (bind is called) to our function.<\/li><\/ul>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t
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      <\/div>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t
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      Payload Data Example Use Case<\/h4>\t\t\t\t<\/div>\n\t\t\t\t
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      You already have a function that takes in 8 parameters and it’s being used in other parts of your code.<\/p>

      The first two arguments of the function match our new delegate function parameters. So:<\/p>

      We already have a function<\/strong> that takes in 8 arguments<\/strong> and we want to bind it to a delegate\u00a0<\/strong>that passes only 2 parameters.\u00a0<\/strong><\/p>

      The solution is to pass the rest of the 6 arguments<\/strong> required by the function as Payload data at BIND time.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t\t<\/div>\n\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t<\/section>\n\t\t\t\t<\/div>\n\t\t","protected":false},"featured_media":0,"template":"","asx-lms-tutorial-categories":[58,45],"asx-lms-tutorial-tags":[46],"class_list":["post-5168","asx-lms-tutorial-cpt","type-asx-lms-tutorial-cpt","status-publish","hentry","asx-lms-tutorial-categories-unreal-c-api","asx-lms-tutorial-categories-unreal-engine","asx-lms-tutorial-tags-cpp","entry"],"acf":[],"_links":{"self":[{"href":"https:\/\/store.algosyntax.com\/asx-rest\/wp\/v2\/asx-lms-tutorial-cpt\/5168","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/store.algosyntax.com\/asx-rest\/wp\/v2\/asx-lms-tutorial-cpt"}],"about":[{"href":"https:\/\/store.algosyntax.com\/asx-rest\/wp\/v2\/types\/asx-lms-tutorial-cpt"}],"version-history":[{"count":0,"href":"https:\/\/store.algosyntax.com\/asx-rest\/wp\/v2\/asx-lms-tutorial-cpt\/5168\/revisions"}],"wp:attachment":[{"href":"https:\/\/store.algosyntax.com\/asx-rest\/wp\/v2\/media?parent=5168"}],"wp:term":[{"taxonomy":"asx-lms-tutorial-categories","embeddable":true,"href":"https:\/\/store.algosyntax.com\/asx-rest\/wp\/v2\/asx-lms-tutorial-categories?post=5168"},{"taxonomy":"asx-lms-tutorial-tags","embeddable":true,"href":"https:\/\/store.algosyntax.com\/asx-rest\/wp\/v2\/asx-lms-tutorial-tags?post=5168"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}