Wt examples  4.2.2
Public Member Functions | Private Member Functions | Private Attributes | List of all members
JavascriptExample Class Reference

An example showing how to interact custom JavaScript with Wt stuff. More...

#include <JavascriptExample.h>

Inheritance diagram for JavascriptExample:
Inheritance graph
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Public Member Functions

 JavascriptExample (const WEnvironment &env)
 Create the example application. More...
 

Private Member Functions

void confirmed ()
 The user has confirmed the payment. More...
 
void setAmount (std::string amount)
 Set the amount to be payed. More...
 

Private Attributes

std::unique_ptr< PopuppromptAmount_
 Popup for changing the amount. More...
 
std::unique_ptr< PopupconfirmPay_
 Popup for paying. More...
 
WText * currentAmount_
 WText for showing the current amount. More...
 

Detailed Description

An example showing how to interact custom JavaScript with Wt stuff.

Definition at line 24 of file JavascriptExample.h.

Constructor & Destructor Documentation

◆ JavascriptExample()

JavascriptExample::JavascriptExample ( const WEnvironment &  env)

Create the example application.

Definition at line 17 of file JavascriptExample.C.

18  : WApplication(env)
19 {
20  setTitle("Javascript example");
21 
22  // Create a popup for prompting the amount of money, and connect the
23  // okPressed button to the slot for setting the amount of money.
24  //
25  // Note that the input provided by the user in the prompt box is passed as
26  // an argument to the slot.
27  promptAmount_ = Popup::createPrompt("How much do you want to pay?","");
28  promptAmount_->okPressed().connect(std::bind(&JavascriptExample::setAmount,
29  this, std::placeholders::_1));
30 
31  // Create a popup for confirming the payment.
32  //
33  // Since a confirm popup does not allow input, we ignore the
34  // argument carrying the input (which will be empty anyway).
36  confirmPay_->okPressed().connect(this, &JavascriptExample::confirmed);
37 
38  root()->addWidget(cpp14::make_unique<WText>("<h2>Wt Javascript example</h2>"
39  "<p>Wt makes abstraction of Javascript, and therefore allows you"
40  " to develop web applications without any knowledge of Javascript,"
41  " and which are not dependent on Javascript."
42  " However, Wt does allow you to add custom Javascript code:</p>"
43  " <ul>"
44  " <li>To call custom JavaScript code from an event handler, "
45  "connect the Wt::EventSignal to a Wt::JSlot.</li>"
46  " <li>To call C++ code from custom JavaScript, use "
47  "Wt.emit() to emit a Wt::JSignal.</li>"
48  " <li>To call custom JavaScript code from C++, use "
49  "WApplication::doJavascript() or Wt::JSlot::exec().</li>"
50  " </ul>"
51  "<p>This simple application shows how to interact between C++ and"
52  " JavaScript using the JSlot and JSignal classes.</p>"));
53 
55  = root()->addWidget(cpp14::make_unique<WText>("Current amount: $" +
56  promptAmount_->defaultValue()));
57 
58  auto amountButton =
59  root()->addWidget(cpp14::make_unique<WPushButton>("Change ..."));
60  amountButton->setMargin(10, Side::Left | Side::Right);
61 
62  root()->addWidget(cpp14::make_unique<WBreak>());
63 
64  auto confirmButton =
65  root()->addWidget(cpp14::make_unique<WPushButton>("Pay now."));
66  confirmButton->setMargin(10, Side::Top | Side::Bottom);
67 
68  // Connect the event handlers to a JSlot: this will execute the JavaScript
69  // immediately, without a server round trip.
70  amountButton->clicked().connect(promptAmount_->show);
71  confirmButton->clicked().connect(confirmPay_->show);
72 
73  // Set the initial amount
74  setAmount("1000");
75 }
void confirmed()
The user has confirmed the payment.
WText * currentAmount_
WText for showing the current amount.
std::unique_ptr< Popup > promptAmount_
Popup for changing the amount.
void setAmount(std::string amount)
Set the amount to be payed.
std::unique_ptr< Popup > confirmPay_
Popup for paying.
static std::unique_ptr< Popup > createConfirm(const WString &message)
Create a confirm dialog.
Definition: Popup.C:73
static std::unique_ptr< Popup > createPrompt(const WString &message, const std::string defaultValue)
Create a prompt dialog with the given default value.
Definition: Popup.C:83

Member Function Documentation

◆ confirmed()

void JavascriptExample::confirmed ( )
private

The user has confirmed the payment.

Definition at line 89 of file JavascriptExample.C.

90 {
91  root()->addWidget(cpp14::make_unique<WText>("<br/>Just payed $" +
92  promptAmount_->defaultValue() + "."));
93 }
std::unique_ptr< Popup > promptAmount_
Popup for changing the amount.

◆ setAmount()

void JavascriptExample::setAmount ( std::string  amount)
private

Set the amount to be payed.

Definition at line 77 of file JavascriptExample.C.

78 {
79  // Change the confirmation message to include the amount.
80  confirmPay_->setMessage("Are you sure you want to pay $" + amount + " ?");
81 
82  // Change the default value for the prompt.
83  promptAmount_->setDefaultValue(amount);
84 
85  // Change the text that shows the current amount.
86  currentAmount_->setText("Current amount: $" + promptAmount_->defaultValue());
87 }
WText * currentAmount_
WText for showing the current amount.
std::unique_ptr< Popup > promptAmount_
Popup for changing the amount.
std::unique_ptr< Popup > confirmPay_
Popup for paying.

Member Data Documentation

◆ confirmPay_

std::unique_ptr<Popup> JavascriptExample::confirmPay_
private

Popup for paying.

Definition at line 46 of file JavascriptExample.h.

◆ currentAmount_

WText* JavascriptExample::currentAmount_
private

WText for showing the current amount.

Definition at line 50 of file JavascriptExample.h.

◆ promptAmount_

std::unique_ptr<Popup> JavascriptExample::promptAmount_
private

Popup for changing the amount.

Definition at line 42 of file JavascriptExample.h.


The documentation for this class was generated from the following files:

Generated on Fri Mar 20 2020 for the C++ Web Toolkit (Wt) by doxygen 1.8.15