Chrome Source Learning: JS and the underlying C + + communication

Take the query history as an example:

1. In the upper History.js, send the event request and related parameters to the bottom through Chrome.send (), where ' queryhistory ' is the signal name, [This.searchtext_, This.offset_, This.rangeindays_, EndTime, MaxResults] is the parameter passed to the bottom:

Chrome.send (' QueryHistory ', [This This] rangeindays_, EndTime, MaxResults]);

2. In the underlying browsing_history_handler.cc, the Registermessages function responds to events from the upper layer:

void browsinghistoryhandler::registermessages () {...  ... WEB_UI ()->registermessagecallback ("queryhistory",      Base :: Bind (&browsinghistoryhandler::handlequeryhistory,                 base:: Unretained (  this))); ...}

The event response for the query history is then processed in the Browsinghistoryhandler::handlequeryhistory () function.

3. After processing, call the upper JS method via Calljavascriptfunction () and return the data that needs to be returned.

void browsinghistoryhandler::returnresultstofrontend () {...  ... WEB_UI (),calljavascriptfunction (      "historyresult", Results_ Info_value_, results_value);

4. Then the upper-layer-specified method, i.e. Historyresult (), obtains the history of the originally specified query and can proceed with the related processing, completing a complete communication above:

function Historyresult (info, results) {  Historymodel.addresults (info, results);}

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Chrome Source Learning: JS and the underlying C + + communication