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/*
* Copyright (C) 2008 Emweb bvba, Kessel-Lo, Belgium.
*
* See the LICENSE file for terms of use.
*/
#include <iostream>
#include <Wt/WApplication>
#include <Wt/WBreak>
#include <Wt/WContainerWidget>
#include <Wt/WText>
#include <Wt/WPushButton>
#include "JavascriptExample.h"
#include "Popup.h"
using namespace Wt;
JavascriptExample::JavascriptExample(const WEnvironment& env)
: WApplication(env)
{
setTitle("Javascript example");
// Create a popup for prompting the amount of money, and connect the
// okPressed button to the slot for setting the amount of money.
//
// Note that the input provided by the user in the prompt box is passed as
// an argument to the slot.
promptAmount_ = Popup::createPrompt("How much do you want to pay?", "",
this);
promptAmount_->okPressed().connect(this, &JavascriptExample::setAmount);
// Create a popup for confirming the payment.
//
// Since a confirm popup does not allow input, we ignore the
// argument carrying the input (which will be empty anyway).
confirmPay_ = Popup::createConfirm("", this);
confirmPay_->okPressed().connect(this, &JavascriptExample::confirmed);
new WText("<h2>Wt Javascript example</h2>"
"<p>Wt makes abstraction of Javascript, and therefore allows you"
" to develop web applications without any knowledge of Javascript,"
" and which are not dependent on Javascript."
" However, Wt does allow you to add custom Javascript code:</p>"
" <ul>"
" <li>To call custom JavaScript code from an event handler, "
"connect the Wt::EventSignal to a Wt::JSlot.</li>"
" <li>To call C++ code from custom JavaScript, use "
"Wt.emit() to emit a Wt::JSignal.</li>"
" <li>To call custom JavaScript code from C++, use "
"WApplication::doJavascript() or Wt::JSlot::exec().</li>"
" </ul>"
"<p>This simple application shows how to interact between C++ and"
" JavaScript using the JSlot and JSignal classes.</p>", root());
currentAmount_
= new WText("Current amount: $" + promptAmount_->defaultValue(), root());
WPushButton *amountButton = new WPushButton("Change ...", root());
amountButton->setMargin(10, Left | Right);
new WBreak(root());
WPushButton *confirmButton = new WPushButton("Pay now.", root());
confirmButton->setMargin(10, Top | Bottom);
// Connect the event handlers to a JSlot: this will execute the JavaScript
// immediately, without a server round trip.
amountButton->clicked().connect(promptAmount_->show);
confirmButton->clicked().connect(confirmPay_->show);
// Set the initial amount
setAmount("1000");
}
void JavascriptExample::setAmount(const std::string amount)
{
// Change the confirmation message to include the amount.
confirmPay_->setMessage("Are you sure you want to pay $" + amount + " ?");
// Change the default value for the prompt.
promptAmount_->setDefaultValue(amount);
// Change the text that shows the current amount.
currentAmount_->setText("Current amount: $" + promptAmount_->defaultValue());
}
void JavascriptExample::confirmed()
{
new WText("<br/>Just payed $" + promptAmount_->defaultValue() + ".", root());
}
WApplication *createApplication(const WEnvironment& env)
{
return new JavascriptExample(env);
}
int main(int argc, char **argv)
{
return WRun(argc, argv, &createApplication);
}
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