forms - Updating variable after AJAX call in jquery -


i want create page whether user makes selection on (django modelchoice) form , results in ajax update of form may trigger additional ajax update. rather rudimentary javascript skills not task!

the problem cannot correctly read value of updated form - 1 step behind think should be. in simplified example below, if jquery calculating value of second_var @ same time first_var (i.e before have updated ajax call). if keep switching between 2 options in #id_first_metric, second_var update pointing value of #id_second_metric before last update.

how can second_var correctly contain newly updated value?

function first_function(first_var){     console.log('first var:' + first_var);     //    correctly states value of first var     var update_url = '/ajax/update_second_metric/first_var';     $('#id_second_metric').load(update_url);  $('#first_metric_selector').change(function () {     var first_var = $('#id_first_metric').val();     first_function(first_var);     $('#second_metric_selector').change(); });  $('#second_metric_selector').change(function () {     var second_var = $('#id_second_metric').val();     console.log('second var' + second_var);     //  fails detect new value of second var created first     //  ajax call });

answer

function first_function(first_var){     console.log('first var:' + first_var);     //    correctly states value of first var     var update_url = '/ajax/update_second_metric/';     $('#id_second_metric').load(update_url, function(){         $('#second_metric_selector').change();     });

"$('#id_second_metric').load(update_url)" happens asynchronously. there no guarantee "$('#second_metric_selector').change()" called before "$('#id_second_metric').load(update_url)" finishes.

you can use callback function provided load guarantee order. see http://api.jquery.com/load/


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