1 | /****************************************************************************
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2 | **
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3 | ** Copyright (C) 2011 Nokia Corporation and/or its subsidiary(-ies).
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4 | ** All rights reserved.
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5 | ** Contact: Nokia Corporation ([email protected])
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6 | **
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7 | ** This file is part of the documentation of the Qt Toolkit.
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8 | **
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9 | ** $QT_BEGIN_LICENSE:FDL$
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10 | ** Commercial Usage
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11 | ** Licensees holding valid Qt Commercial licenses may use this file in
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12 | ** accordance with the Qt Commercial License Agreement provided with the
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13 | ** Software or, alternatively, in accordance with the terms contained in a
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14 | ** written agreement between you and Nokia.
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15 | **
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16 | ** GNU Free Documentation License
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17 | ** Alternatively, this file may be used under the terms of the GNU Free
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18 | ** Documentation License version 1.3 as published by the Free Software
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19 | ** Foundation and appearing in the file included in the packaging of this
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20 | ** file.
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21 | **
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22 | ** If you have questions regarding the use of this file, please contact
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23 | ** Nokia at [email protected].
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24 | ** $QT_END_LICENSE$
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25 | **
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26 | ****************************************************************************/
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27 |
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28 | /*!
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29 | \example script/calculator
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30 | \title QtScript Calculator Example
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31 |
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32 | In this simple QtScript example, we show how to implement the
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33 | functionality of a calculator widget.
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34 |
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35 | \image qtscript-calculator-example.png
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36 |
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37 | The program logic in this example is a fairly straight port of the logic in the C++ \l{Calculator Example}.
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38 | The graphical user interface is defined in a UI file.
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39 |
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40 | The C++ part of the example consists of four steps:
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41 | \list
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42 | \o Evaluate the script code that defines the \c{Calculator} class.
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43 |
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44 | \snippet examples/script/calculator/main.cpp 0a
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45 | \snippet examples/script/calculator/main.cpp 0b
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46 |
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47 | \o Create a widget from the UI file using QUiLoader.
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48 |
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49 | \snippet examples/script/calculator/main.cpp 1
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50 |
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51 | \o Call the Calculator constructor function to create a new \c{Calculator} script object, passing the widget as argument.
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52 |
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53 | \snippet examples/script/calculator/main.cpp 2
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54 |
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55 | \o Show the widget and start the application event loop.
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56 |
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57 | \snippet examples/script/calculator/main.cpp 3
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58 |
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59 | \endlist
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60 |
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61 | On the script side, the \c{Calculator} constructor function
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62 | initializes the instance variables of the new \c{Calculator}
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63 | object, and connects the clicked() signal of the form's buttons
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64 | to corresponding functions defined in the \c{Calculator} prototype
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65 | object; the effect is that when a button is clicked, the proper
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66 | script function will be invoked to carry out the operation.
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67 |
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68 | \snippet examples/script/calculator/calculator.js 0
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69 |
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70 | A \c{Calculator} object is just a plain script object; it is not
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71 | a widget. Instead, it stores a reference to the calculator form
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72 | (the widget) in an instance variable, \c{ui}. The calculator
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73 | script functions can access components of the form by referring
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74 | to the proper children of the \c{ui} member.
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75 |
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76 | \snippet examples/script/calculator/calculator.js 1
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77 |
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78 | The digitClicked() function is called when a digit button is
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79 | clicked, with the input digit as argument.
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80 |
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81 | \snippet examples/script/calculator/calculator.js 2
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82 |
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83 | The changeSign() function shows how we retrieve the text property
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84 | of the calculator's display, change it appropriately, and write
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85 | back the new value.
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86 |
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87 |
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88 | */
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