Wt

#include <Wt/WDefaultLoadingIndicator.h>

#include <Wt/WStringStream.h>

class customLoadingIndicator: public WDefaultLoadingIndicator

{

public:

customLoadingIndicator() : WDefaultLoadingIndicator(),

handleShow_(this, "handleShow"),

handleHide_(this, "handleHide")

{

WStringStream js1;

js1 << "Wt.emit(" << jsRef() << ", 'handleShow', Date.now());";

implementJavaScript(&WWidget::show, js1.str());

WStringStream js2;

js2 << "Wt.emit(" << jsRef() << ", 'handleHide', Date.now());";

implementJavaScript(&WWidget::hide, js2.str());

handleShow_.connect(std::bind(&customLoadingIndicator::handleShow, this, std::placeholders::_1));

handleHide_.connect(std::bind(&customLoadingIndicator::handleHide, this, std::placeholders::_1));

}

void handleShow(std::string show_time_s) {

log("info") << "handleShow: " << show_time_s;

last_shown = stol(show_time_s);

}

void handleHide(std::string hide_time_s) {

log("info") << "handleHide: " << hide_time_s;

long hide_time = stol(hide_time_s);

if (last_shown) {

long elapsed = hide_time - last_shown + 500;

log("info") << "wait indicator was shown for " << elapsed << "ms";

}

}

void setHidden(bool hidden, const WAnimation &animation=WAnimation() ) override {

Wt::WCompositeWidget::setHidden(hidden, animation);

Wt::log("info") << "setHidden called";

}

private:

long last_shown = 0;

JSignal<std::string> handleShow_;

JSignal<std::string> handleHide_;

};

auto loadingIndicator = std::make_unique<customLoadingIndicator>();

setLoadingIndicator(std::move(loadingIndicator));