From bd0f3345a938b35ce6a12f6150373b0955b8dd12 Mon Sep 17 00:00:00 2001 From: Timothy Pearson Date: Sun, 10 Jul 2011 15:24:15 -0500 Subject: Add Qt3 development HEAD version --- doc/html/tutorial2-09.html | 249 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 249 insertions(+) create mode 100644 doc/html/tutorial2-09.html (limited to 'doc/html/tutorial2-09.html') diff --git a/doc/html/tutorial2-09.html b/doc/html/tutorial2-09.html new file mode 100644 index 0000000..5646d34 --- /dev/null +++ b/doc/html/tutorial2-09.html @@ -0,0 +1,249 @@ + + + + + +Setting Options + + + + + + + +

Setting Options

+ + +

We provide an options dialog so that the user can set options that +apply to all data sets in one place. +

(Extracts from optionsform.h.) +

+ +

    class OptionsForm : public QDialog
+    {
+        Q_OBJECT
+    public:
+        OptionsForm( QWidget* parent = 0, const char* name = "options form",
+                     bool modal = FALSE, WFlags f = 0 );
+        ~OptionsForm() {}
+
+        QFont font() const { return m_font; }
+        void setFont( QFont font );
+
+        QLabel *chartTypeTextLabel;
+        QComboBox *chartTypeComboBox;
+        QPushButton *fontPushButton;
+        QLabel *fontTextLabel;
+        QFrame *addValuesFrame;
+        QButtonGroup *addValuesButtonGroup;
+        QRadioButton *noRadioButton;
+        QRadioButton *yesRadioButton;
+        QRadioButton *asPercentageRadioButton;
+        QLabel *decimalPlacesTextLabel;
+        QSpinBox *decimalPlacesSpinBox;
+        QPushButton *okPushButton;
+        QPushButton *cancelPushButton;
+
+    protected slots:
+        void chooseFont();
+
+    protected:
+        QVBoxLayout *optionsFormLayout;
+        QHBoxLayout *chartTypeLayout;
+        QHBoxLayout *fontLayout;
+        QVBoxLayout *addValuesFrameLayout;
+        QVBoxLayout *addValuesButtonGroupLayout;
+        QHBoxLayout *decimalPlacesLayout;
+        QHBoxLayout *buttonsLayout;
+
+    private:
+        QFont m_font;
+    };
+

The layout of this dialog is slightly more complicated than for the +set data form, but we only need a single slot. Unlike the "smart" set +data form this is a "dumb" dialog that simply provides the widgets for +the caller to set and read. The caller is responsible for updating +things based on the changes the user makes. +

(Extracts from optionsform.cpp.) +

+ +

    #include "images/options_horizontalbarchart.xpm"
+    #include "images/options_piechart.xpm"
+    #include "images/options_verticalbarchart.xpm"
+

We include some some pixmaps to use in the chart type combobox. +

The Constructor +

    OptionsForm::OptionsForm( QWidget* parent, const char* name,
+                              bool modal, WFlags f )
+        : QDialog( parent, name, modal, f )
+    {
+        setCaption( "Chart -- Options" );
+        resize( 320, 290 );
+

We pass all the arguments on to the QDialog constructor, set a caption +and set an initial size. +

The layout of the form will be to have the chart type label and combo +box in a horizontal box layout, and similarly for the font button and +font label, and for the decimal places label and spinbox. The +buttons will also be placed in a horizontal layout, but with a spacer +to move them to the right. The show values radio buttons will be +vertically aligned within a frame. All of these will be laid out in a +vertical box layout. +

        optionsFormLayout = new QVBoxLayout( this, 11, 6 );
+

All the widgets will be laid out within the form's vertical box layout. +

        chartTypeLayout = new QHBoxLayout( 0, 0, 6 );
+

The chart type label and combobox will be laid out side by side. +

        chartTypeTextLabel = new QLabel( "&Chart Type", this );
+        chartTypeLayout->addWidget( chartTypeTextLabel );
+
+        chartTypeComboBox = new QComboBox( FALSE, this );
+        chartTypeComboBox->insertItem( QPixmap( options_piechart ), "Pie Chart" );
+        chartTypeComboBox->insertItem( QPixmap( options_verticalbarchart ),
+                                       "Vertical Bar Chart" );
+        chartTypeComboBox->insertItem( QPixmap( options_horizontalbarchart ),
+                                       "Horizontal Bar Chart" );
+        chartTypeLayout->addWidget( chartTypeComboBox );
+        optionsFormLayout->addLayout( chartTypeLayout );
+

We create the chart type label (with an accelerator which we'll relate +to the chart type combobox later). We also create a chart type +combobox, populating it with both pixmaps and text. We add them both +to the horizontal layout and add the horizontal layout to the form's +vertical layout. +

        fontLayout = new QHBoxLayout( 0, 0, 6 );
+
+        fontPushButton = new QPushButton( "&Font...", this );
+        fontLayout->addWidget( fontPushButton );
+        QSpacerItem* spacer = new QSpacerItem( 0, 0,
+                                               QSizePolicy::Expanding,
+                                               QSizePolicy::Minimum );
+        fontLayout->addItem( spacer );
+
+        fontTextLabel = new QLabel( this ); // Must be set by caller via setFont()
+        fontLayout->addWidget( fontTextLabel );
+        optionsFormLayout->addLayout( fontLayout );
+

We create a horizontal box layout to hold the font button and font +label. The font button is straight-forward. We add a spacer to improve +the appearance. The font text label is initially empty (since we don't +know what font the user is using). +

        addValuesFrame = new QFrame( this );
+        addValuesFrame->setFrameShape( QFrame::StyledPanel );
+        addValuesFrame->setFrameShadow( QFrame::Sunken );
+        addValuesFrameLayout = new QVBoxLayout( addValuesFrame, 11, 6 );
+
+        addValuesButtonGroup = new QButtonGroup( "Show Values", addValuesFrame );
+        addValuesButtonGroup->setColumnLayout(0, Qt::Vertical );
+        addValuesButtonGroup->layout()->setSpacing( 6 );
+        addValuesButtonGroup->layout()->setMargin( 11 );
+        addValuesButtonGroupLayout = new QVBoxLayout(
+                                            addValuesButtonGroup->layout() );
+        addValuesButtonGroupLayout->setAlignment( Qt::AlignTop );
+
+        noRadioButton = new QRadioButton( "&No", addValuesButtonGroup );
+        noRadioButton->setChecked( TRUE );
+        addValuesButtonGroupLayout->addWidget( noRadioButton );
+
+        yesRadioButton = new QRadioButton( "&Yes", addValuesButtonGroup );
+        addValuesButtonGroupLayout->addWidget( yesRadioButton );
+
+        asPercentageRadioButton = new QRadioButton( "As &Percentage",
+                                                    addValuesButtonGroup );
+        addValuesButtonGroupLayout->addWidget( asPercentageRadioButton );
+        addValuesFrameLayout->addWidget( addValuesButtonGroup );
+

The user may opt to display their own labels as they are or to add the +values at the end of each label, either as-is or as percentages. +

We create a frame to present the radio buttons in and create a layout +for them. We create a button group (so that Qt will take care of +handling the exclusive radio button behaviour automatically). Next we +create the radio buttons, making "No" the default. +

The decimal places label and spin box are laid out just like the other +horizontal layouts, and the buttons are laid out in a very similar way +to the buttons in the set data form. +

        connect( fontPushButton, SIGNAL( clicked() ), this, SLOT( chooseFont() ) );
+        connect( okPushButton, SIGNAL( clicked() ), this, SLOT( accept() ) );
+        connect( cancelPushButton, SIGNAL( clicked() ), this, SLOT( reject() ) );
+

We only need three connections: +

When the user clicks the font button we execute our own +chooseFont() slot. +
If the user clicks OK we call QDialog::accept(); it is up to the +caller to read the data from the dialog's widgets and perform any +necessary actions. +
If the user clicks Cancel we call QDialog::reject(). +

        chartTypeTextLabel->setBuddy( chartTypeComboBox );
+        decimalPlacesTextLabel->setBuddy( decimalPlacesSpinBox );
+

We use the setBuddy() function to associate widgets with label +accelerators. +

The Slots +

    void OptionsForm::chooseFont()
+    {
+        bool ok;
+        QFont font = QFontDialog::getFont( &ok, m_font, this );
+        if ( ok )
+            setFont( font );
+    }
+

When the user clicks the Font button this slot is invoked. It simply +calls the static QFontDialog::getFont() function to obtain the user's +choice of font. If they chose a font we call our setFont() slot which +will present a textual description of the font in the font label. +

    void OptionsForm::setFont( QFont font )
+    {
+        QString label = font.family() + " " +
+                        QString::number( font.pointSize() ) + "pt";
+        if ( font.bold() )
+            label += " Bold";
+        if ( font.italic() )
+            label += " Italic";
+        fontTextLabel->setText( label );
+        m_font = font;
+    }
+

This function displays a textual description of the chosen font in the +font label and holds a copy of the font in the m_font member. We +need the font in a member so that we can provide a default font for +chooseFont(). +

+« Taking Data | +Contents | +The Project File » +

+ +

Trademarks +

Qt 3.3.8

+ -- cgit v1.2.3