From d796c9dd933ab96ec83b9a634feedd5d32e1ba3f Mon Sep 17 00:00:00 2001 From: Timothy Pearson Date: Tue, 8 Nov 2011 12:31:36 -0600 Subject: Test conversion to TQt3 from Qt3 8c6fc1f8e35fd264dd01c582ca5e7549b32ab731 --- doc/html/tutorial2-08.html | 349 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 349 insertions(+) create mode 100644 doc/html/tutorial2-08.html (limited to 'doc/html/tutorial2-08.html') diff --git a/doc/html/tutorial2-08.html b/doc/html/tutorial2-08.html new file mode 100644 index 000000000..77719f583 --- /dev/null +++ b/doc/html/tutorial2-08.html @@ -0,0 +1,349 @@ + + + + + +Taking Data + + + + + + + +

Taking Data

+ + +

The set data dialog allows the user to add and edit values, and to +choose the color and pattern used to display values. Users can also +enter label text and choose a label color for each label. +

(Extracts from setdataform.h.) +

+ +

    class SetDataForm: public TQDialog
+    {
+        Q_OBJECT
+    public:
+        SetDataForm( ElementVector *elements, int decimalPlaces,
+                     TQWidget *parent = 0, const char *name = "set data form",
+                     bool modal = TRUE, WFlags f = 0 );
+        ~SetDataForm() {}
+
+    public slots:
+        void setColor();
+        void setColor( int row, int col );
+        void currentChanged( int row, int col );
+        void valueChanged( int row, int col );
+
+    protected slots:
+        void accept();
+
+    private:
+        TQTable *table;
+        TQPushButton *colorPushButton;
+        TQPushButton *okPushButton;
+        TQPushButton *cancelPushButton;
+
+    protected:
+        TQVBoxLayout *tableButtonBox;
+        TQHBoxLayout *buttonBox;
+
+    private:
+        ElementVector *m_elements;
+        int m_decimalPlaces;
+    };
+

The header file is simple. The constructor takes a pointer to the +element vector so that this "smart" dialog can display and edit the +data directly. We'll explain the slots as we look through the +implementation. +

(Extracts from setdataform.cpp.) +

+ +

    #include "images/pattern01.xpm"
+    #include "images/pattern02.xpm"
+

We have created a small .XPM image to show each brush pattern that +TQt supports. We'll use these in the pattern combobox. +

The Constructor +

    SetDataForm::SetDataForm( ElementVector *elements, int decimalPlaces,
+                              TQWidget* parent,  const char* name,
+                              bool modal, WFlags f )
+        : TQDialog( parent, name, modal, f )
+
+    {
+        m_elements = elements;
+        m_decimalPlaces = decimalPlaces;
+

We pass most of the arguments to the TQDialog superclass. We assign the +elements vector pointer and the number of decimal places to display to +member variables so that they are accessible by all SetDataForm's +member functions. +

        setCaption( "Chart -- Set Data" );
+        resize( 540, 440 );
+

We set a caption for the dialog and resize it. +

        tableButtonBox = new TQVBoxLayout( this, 11, 6, "table button box layout" );
+

The layout of the form is tquite simple. The buttons will be grouped +together in a horizontal layout and the table and the button layout +will be grouped together vertically using the tableButtonBox layout. +

        table = new TQTable( this, "data table" );
+        table->setNumCols( 5 );
+        table->setNumRows( ChartForm::MAX_ELEMENTS );
+        table->setColumnReadOnly( 1, TRUE );
+        table->setColumnReadOnly( 2, TRUE );
+        table->setColumnReadOnly( 4, TRUE );
+        table->setColumnWidth( 0, 80 );
+        table->setColumnWidth( 1, 60 ); // Columns 1 and 4 must be equal
+        table->setColumnWidth( 2, 60 );
+        table->setColumnWidth( 3, 200 );
+        table->setColumnWidth( 4, 60 );
+        TQHeader *th = table->horizontalHeader();
+        th->setLabel( 0, "Value" );
+        th->setLabel( 1, "Color" );
+        th->setLabel( 2, "Pattern" );
+        th->setLabel( 3, "Label" );
+        th->setLabel( 4, "Color" );
+        tableButtonBox->addWidget( table );
+

We create a new TQTable with five columns, and the same number of rows +as we have elements in the elements vector. We make the color and +pattern columns read only: this is to prevent the user typing in them. +We will make the color changeable by the user clicking on a color or +navigating to a color and clicking the Color button. The pattern will +be in a combobox, changeable simply by the user selecting a different +pattern. Next we set suitable initial widths, insert labels for each +column and finally add the table to the tableButtonBox layout. +

        buttonBox = new TQHBoxLayout( 0, 0, 6, "button box layout" );
+

We create a horizontal box layout to hold the buttons. +

        colorPushButton = new TQPushButton( this, "color button" );
+        colorPushButton->setText( "&Color..." );
+        colorPushButton->setEnabled( FALSE );
+        buttonBox->addWidget( colorPushButton );
+

We create a color button and add it to the buttonBox layout. We +disable the button; we will only enable it when the focus is actually +on a color cell. +

        TQSpacerItem *spacer = new TQSpacerItem( 0, 0, TQSizePolicy::Expanding,
+                                                     TQSizePolicy::Minimum );
+        buttonBox->addItem( spacer );
+

Since we want to separate the color button from the OK and Cancel +buttons we next create a spacer and add that to the buttonBox layout. +

        okPushButton = new TQPushButton( this, "ok button" );
+        okPushButton->setText( "OK" );
+        okPushButton->setDefault( TRUE );
+        buttonBox->addWidget( okPushButton );
+
+        cancelPushButton = new TQPushButton( this, "cancel button" );
+        cancelPushButton->setText( "Cancel" );
+        cancelPushButton->setAccel( Key_Escape );
+        buttonBox->addWidget( cancelPushButton );
+

The OK and Cancel buttons are created and added to the buttonBox. We +make the OK button the dialog's default button, and we make the Esc +key an accelerator for the Cancel button. +

        tableButtonBox->addLayout( buttonBox );
+

We add the buttonBox layout to the tableButtonBox and the layout is +complete. +

        connect( table, SIGNAL( clicked(int,int,int,const TQPoint&) ),
+                 this, SLOT( setColor(int,int) ) );
+        connect( table, SIGNAL( currentChanged(int,int) ),
+                 this, SLOT( currentChanged(int,int) ) );
+        connect( table, SIGNAL( valueChanged(int,int) ),
+                 this, SLOT( valueChanged(int,int) ) );
+        connect( colorPushButton, SIGNAL( clicked() ), this, SLOT( setColor() ) );
+        connect( okPushButton, SIGNAL( clicked() ), this, SLOT( accept() ) );
+        connect( cancelPushButton, SIGNAL( clicked() ), this, SLOT( reject() ) );
+

We now "wire up" the form. +

If the user clicks a cell we call the setColor() slot; this will +check that the cell is one that holds a color, and if it is, will +invoke the color dialog. +
We connect the TQTable's currentChanged() signal to our own +currentChanged() slot; this will be used to enable/disable the color +button for example, depending on which column the user is in. +
We connect the table's valueChanged() signal to our own +valueChanged() slot; we'll use this to display the value with the +correct number of decimal places. +
If the user clicks the Color button we call a setColor() slot. +
The OK button is connected to the accept() slot; we will update the +elements vector in this slot. +
The Cancel button is connected to the TQDialog reject() slot, and +retquires no further code or action on our part. +

        TQPixmap patterns[MAX_PATTERNS];
+        patterns[0]  = TQPixmap( pattern01 );
+        patterns[1]  = TQPixmap( pattern02 );
+

We create a pixmap for every brush pattern and store them in the patterns array. +

        TQRect rect = table->cellRect( 0, 1 );
+        TQPixmap pix( rect.width(), rect.height() );
+

We obtain the rectangle that will be occupied by each color cell and +create a blank pixmap of that size. +

        for ( int i = 0; i < ChartForm::MAX_ELEMENTS; ++i ) {
+            Element element = (*m_elements)[i];
+
+            if ( element.isValid() )
+                table->setText(
+                    i, 0,
+                    TQString( "%1" ).arg( element.value(), 0, 'f',
+                                         m_decimalPlaces ) );
+
+            TQColor color = element.valueColor();
+            pix.fill( color );
+            table->setPixmap( i, 1, pix );
+            table->setText( i, 1, color.name() );
+
+            TQComboBox *combobox = new TQComboBox;
+            for ( int j = 0; j < MAX_PATTERNS; ++j )
+                combobox->insertItem( patterns[j] );
+            combobox->setCurrentItem( element.valuePattern() - 1 );
+            table->setCellWidget( i, 2, combobox );
+
+            table->setText( i, 3, element.label() );
+
+            color = element.labelColor();
+            pix.fill( color );
+            table->setPixmap( i, 4, pix );
+            table->setText( i, 4, color.name() );
+

For each element in the element vector we must populate the table. +

If the element is valid we write its value in the first column (column +0, Value), formatting it with the specified number of decimal places. +

We read the element's value color and fill the blank pixmap with that +color; we then set the color cell to display this pixmap. We need to +be able to read back the color later (e.g. if the user changes it). +One way of doing this would be to examine a pixel in the pixmap; +another way would be to subclass TQTableItem (in a similar way to our +CanvasText subclass) and store the color there. But we've taken a +simpler route: we set the cell's text to the name of the color. +

Next we populate the pattern combobox with the patterns. We will use +the position of the chosen pattern in the combobox to determine which +pattern the user has selected. TQTable can make use of TQComboTableItem +items; but these only support text, so we use setCellWidget() to +insert TQComboBox's into the table instead. +

Next we insert the element's label. Finally we set the label color in +the same way as we set the value color. +

The Slots +

    void SetDataForm::currentChanged( int, int col )
+    {
+        colorPushButton->setEnabled( col == 1 || col == 4 );
+    }
+

As the user navigates through the table currentChanged() signals are +emitted. If the user enters column 1 or 4 (value color or label color) +we enable the colorPushButton; otherwise we disable it. +

    void SetDataForm::valueChanged( int row, int col )
+    {
+        if ( col == 0 ) {
+            bool ok;
+            double d = table->text( row, col ).toDouble( &ok );
+            if ( ok && d > EPSILON )
+                table->setText(
+                    row, col, TQString( "%1" ).arg(
+                                d, 0, 'f', m_decimalPlaces ) );
+            else if ( !table->text( row, col ).isEmpty() )
+                table->setText( row, col, table->text( row, col ) + "?" );
+        }
+    }
+

If the user changes the value we must format it using the correct +number of decimal places, or indicate that it is invalid. +

    void SetDataForm::setColor()
+    {
+        setColor( table->currentRow(), table->currentColumn() );
+        table->setFocus();
+    }
+

If the user presses the Color button we call the other setColor() +function and put the focus back into the table. +

    void SetDataForm::setColor( int row, int col )
+    {
+        if ( !( col == 1 || col == 4 ) )
+            return;
+
+        TQColor color = TQColorDialog::getColor(
+                            TQColor( table->text( row, col ) ),
+                            this, "color dialog" );
+        if ( color.isValid() ) {
+            TQPixmap pix = table->pixmap( row, col );
+            pix.fill( color );
+            table->setPixmap( row, col, pix );
+            table->setText( row, col, color.name() );
+        }
+    }
+

If this function is called with the focus on a color cell we call +the static TQColorDialog::getColor() dialog to get the user's choice of +color. If they chose a color we fill the color cell's pixmap with that +color and set the cell's text to the new color's name. +

    void SetDataForm::accept()
+    {
+        bool ok;
+        for ( int i = 0; i < ChartForm::MAX_ELEMENTS; ++i ) {
+            Element &element = (*m_elements)[i];
+            double d = table->text( i, 0 ).toDouble( &ok );
+            if ( ok )
+                element.setValue( d );
+            else
+                element.setValue( Element::INVALID );
+            element.setValueColor( TQColor( table->text( i, 1 ) ) );
+            element.setValuePattern(
+                    ((TQComboBox*)table->cellWidget( i, 2 ))->currentItem() + 1 );
+            element.setLabel( table->text( i, 3 ) );
+            element.setLabelColor( TQColor( table->text( i, 4 ) ) );
+        }
+
+        TQDialog::accept();
+    }
+

If the user clicks OK we must update the elements vector. We iterate +over the vector and set each element's value to the value the user has +entered or INVALID if the value is invalid. We set the value color +and the label color by constructing TQColor temporaries that take a +color name as argument. The pattern is set to the pattern combobox's +current item with an offset of 1 (since our pattern numbers begin at +1, but the combobox's items are indexed from 0). +

Finally we call TQDialog::accept(). +

+« File Handling | +Contents | +Setting Options » +

+ +

Trademarks +

TQt 3.3.8

+ -- cgit v1.2.1