com.trolltech.qt.gui
Class QFontDatabase

java.lang.Object
  extended by com.trolltech.qt.QSignalEmitter
      extended by com.trolltech.qt.QtJambiObject
          extended by com.trolltech.qt.gui.QFontDatabase
All Implemented Interfaces:
QtJambiInterface

public class QFontDatabase
extends QtJambiObject

The QFontDatabase class provides information about the fonts available in the underlying window system.

The most common uses of this class are to query the database for the list of font families and for the pointSizes and styles that are available for each family. An alternative to pointSizes is smoothSizes which returns the sizes at which a given family and style will look attractive.

If the font family is available from two or more foundries the foundry name is included in the family name, e.g. "Helvetica [Adobe]" and "Helvetica [Cronyx]". When you specify a family you can either use the old hyphenated Qt 2.x "foundry-family" format, e.g. "Cronyx-Helvetica", or the new bracketed Qt 3.x "family [foundry]" format e.g. "Helvetica [Cronyx]". If the family has a foundry it is always returned, e.g. by families, using the bracketed format.

The font function returns a QFont given a family, style and point size.

A family and style combination can be checked to see if it is italic or bold, and to retrieve its weight. Similarly we can call isBitmapScalable, isSmoothlyScalable, isScalable and isFixedPitch.

Use the styleString to obtain a text version of a style.

The QFontDatabase class also supports some static functions, for example, standardSizes. You can retrieve the description of a writing system using writingSystemName, and a sample of characters in a writing system with writingSystemSample.

Example:

        QFontDatabase database;
        QTreeWidget fontTree;
        fontTree.setColumnCount(2);
        fontTree.setHeaderLabels(QStringList() << "Font" << "Smooth Sizes");

        foreach (QString family, database.families()) {
            QTreeWidgetItem *familyItem = new QTreeWidgetItem(&fontTree);
            familyItem->setText(0, family);

            foreach (QString style, database.styles(family)) {
                QTreeWidgetItem *styleItem = new QTreeWidgetItem(familyItem);
                styleItem->setText(0, style);

                QString sizes;
                foreach (int points, database.smoothSizes(family, style))
                    sizes += QString::number(points) + " ";

                styleItem->setText(1, sizes.trimmed());
            }
        }

This example gets the list of font families, the list of styles for each family, and the point sizes that are available for each combination of family and style, displaying this information in a tree view.

See Also:
QFont, QFontInfo, QFontMetrics, QFontComboBox, Map Example

Nested Class Summary
static class QFontDatabase.WritingSystem
          Press link for info on QFontDatabase.WritingSystem
 
Nested classes/interfaces inherited from class com.trolltech.qt.QSignalEmitter
QSignalEmitter.Signal0, QSignalEmitter.Signal1<A>, QSignalEmitter.Signal2<A,B>, QSignalEmitter.Signal3<A,B,C>, QSignalEmitter.Signal4<A,B,C,D>, QSignalEmitter.Signal5<A,B,C,D,E>, QSignalEmitter.Signal6<A,B,C,D,E,F>, QSignalEmitter.Signal7<A,B,C,D,E,F,G>, QSignalEmitter.Signal8<A,B,C,D,E,F,G,H>, QSignalEmitter.Signal9<A,B,C,D,E,F,G,H,I>
 
Constructor Summary
QFontDatabase()
          Creates a font database object.
 
Method Summary
static int addApplicationFont(java.lang.String fileName)
          Loads the font from the file specified by fileName and makes it available to the application.
static int addApplicationFontFromData(QByteArray fontData)
          Loads the font from binary data specified by fontData and makes it available to the application.
static java.util.List<java.lang.String> applicationFontFamilies(int id)
          Returns a list of font families for the given application font identified by id.
 boolean bold(java.lang.String family, java.lang.String style)
          Returns true if the font that has family family and style style is bold; otherwise returns false.
 java.util.List<java.lang.String> families()
          Returns a sorted list of the available font families.
 java.util.List<java.lang.String> families(QFontDatabase.WritingSystem writingSystem)
          Returns a sorted list of the available font families which support the writingSystem.
 QFont font(java.lang.String family, java.lang.String style, int pointSize)
          Returns a QFont object that has family family, style style and point size pointSize.
static QFontDatabase fromNativePointer(QNativePointer nativePointer)
          This function returns the QFontDatabase instance pointed to by nativePointer
 boolean isBitmapScalable(java.lang.String family)
          Equivalent to isBitmapScalable(family, QString()).
 boolean isBitmapScalable(java.lang.String family, java.lang.String style)
          Returns true if the font that has family family and style style is a scalable bitmap font; otherwise returns false.
 boolean isFixedPitch(java.lang.String family)
          Equivalent to isFixedPitch(family, QString()).
 boolean isFixedPitch(java.lang.String family, java.lang.String style)
          Returns true if the font that has family family and style style is fixed pitch; otherwise returns false.
 boolean isScalable(java.lang.String family)
          Equivalent to isScalable(family, QString()).
 boolean isScalable(java.lang.String family, java.lang.String style)
          Returns true if the font that has family family and style style is scalable; otherwise returns false.
 boolean isSmoothlyScalable(java.lang.String family)
          Equivalent to isSmoothlyScalable(family, QString()).
 boolean isSmoothlyScalable(java.lang.String family, java.lang.String style)
          Returns true if the font that has family family and style style is smoothly scalable; otherwise returns false.
 boolean italic(java.lang.String family, java.lang.String style)
          Returns true if the font that has family family and style style is italic; otherwise returns false.
static QNativePointer nativePointerArray(QFontDatabase[] array)
          This function returns a QNativePointer that is pointing to the specified QFontDatabase array.
 java.util.List<java.lang.Integer> pointSizes(java.lang.String family)
          Returns a list of the point sizes available for the font that has the specified family.
 java.util.List<java.lang.Integer> pointSizes(java.lang.String family, java.lang.String style)
          Returns a list of the point sizes available for the font that has family family and style style.
static boolean removeAllApplicationFonts()
          Removes all application-local fonts previously added using addApplicationFont and addApplicationFontFromData.
static boolean removeApplicationFont(int id)
          Removes the previously loaded application font identified by id.
 java.util.List<java.lang.Integer> smoothSizes(java.lang.String family, java.lang.String style)
          Returns the point sizes of a font that has family family and style style that will look attractive.
static java.util.List<java.lang.Integer> standardSizes()
          Returns a list of standard font sizes.
 java.util.List<java.lang.String> styles(java.lang.String family)
          Returns a list of the styles available for the font family family.
 java.lang.String styleString(QFont font)
          Returns a string that describes the style of the font.
 java.lang.String styleString(QFontInfo fontInfo)
          Returns a string that describes the style of the fontInfo.
 int weight(java.lang.String family, java.lang.String style)
          Returns the weight of the font that has family family and style style.
static java.lang.String writingSystemName(QFontDatabase.WritingSystem writingSystem)
          Returns the names the writingSystem (e.g. for displaying to the user in a dialog).
 java.util.List<QFontDatabase.WritingSystem> writingSystems()
          Returns a sorted list of the available writing systems.
 java.util.List<QFontDatabase.WritingSystem> writingSystems(java.lang.String family)
          Returns a sorted list of the writing systems supported by a given font family.
static java.lang.String writingSystemSample(QFontDatabase.WritingSystem writingSystem)
          Returns a string with sample characters from writingSystem.
 
Methods inherited from class com.trolltech.qt.QtJambiObject
dispose, disposed, finalize, reassignNativeResources, tr, tr, tr
 
Methods inherited from class com.trolltech.qt.QSignalEmitter
blockSignals, disconnect, disconnect, signalsBlocked, signalSender, thread
 
Methods inherited from class java.lang.Object
clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface com.trolltech.qt.QtJambiInterface
disableGarbageCollection, nativeId, nativePointer, reenableGarbageCollection, setJavaOwnership
 

Constructor Detail

QFontDatabase

public QFontDatabase()

Creates a font database object.

Method Detail

bold

public final boolean bold(java.lang.String family,
                          java.lang.String style)

Returns true if the font that has family family and style style is bold; otherwise returns false.

See Also:
italic, weight

families

public final java.util.List<java.lang.String> families()
Returns a sorted list of the available font families.


families

public final java.util.List<java.lang.String> families(QFontDatabase.WritingSystem writingSystem)

Returns a sorted list of the available font families which support the writingSystem.

If a family exists in several foundries, the returned name for that font is in the form "family [foundry]". Examples: "Times [Adobe]", "Times [Cronyx]", "Palatino".

See Also:
writingSystems

font

public final QFont font(java.lang.String family,
                        java.lang.String style,
                        int pointSize)

Returns a QFont object that has family family, style style and point size pointSize. If no matching font could be created, a QFont object that uses the application's default font is returned.


isBitmapScalable

public final boolean isBitmapScalable(java.lang.String family)

Equivalent to isBitmapScalable(family, QString()).


isBitmapScalable

public final boolean isBitmapScalable(java.lang.String family,
                                      java.lang.String style)

Returns true if the font that has family family and style style is a scalable bitmap font; otherwise returns false. Scaling a bitmap font usually produces an unattractive hardly readable result, because the pixels of the font are scaled. If you need to scale a bitmap font it is better to scale it to one of the fixed sizes returned by smoothSizes.

See Also:
isScalable, isSmoothlyScalable

isFixedPitch

public final boolean isFixedPitch(java.lang.String family)

Equivalent to isFixedPitch(family, QString()).


isFixedPitch

public final boolean isFixedPitch(java.lang.String family,
                                  java.lang.String style)

Returns true if the font that has family family and style style is fixed pitch; otherwise returns false.


isScalable

public final boolean isScalable(java.lang.String family)

Equivalent to isScalable(family, QString()).


isScalable

public final boolean isScalable(java.lang.String family,
                                java.lang.String style)

Returns true if the font that has family family and style style is scalable; otherwise returns false.

See Also:
isBitmapScalable, isSmoothlyScalable

isSmoothlyScalable

public final boolean isSmoothlyScalable(java.lang.String family)

Equivalent to isSmoothlyScalable(family, QString()).


isSmoothlyScalable

public final boolean isSmoothlyScalable(java.lang.String family,
                                        java.lang.String style)

Returns true if the font that has family family and style style is smoothly scalable; otherwise returns false. If this function returns true, it's safe to scale this font to any size, and the result will always look attractive.

See Also:
isScalable, isBitmapScalable

italic

public final boolean italic(java.lang.String family,
                            java.lang.String style)

Returns true if the font that has family family and style style is italic; otherwise returns false.

See Also:
weight, bold

pointSizes

public final java.util.List<java.lang.Integer> pointSizes(java.lang.String family)
Returns a list of the point sizes available for the font that has the specified family. The list may be empty.


pointSizes

public final java.util.List<java.lang.Integer> pointSizes(java.lang.String family,
                                                          java.lang.String style)

Returns a list of the point sizes available for the font that has family family and style style. The list may be empty.

See Also:
smoothSizes, standardSizes

smoothSizes

public final java.util.List<java.lang.Integer> smoothSizes(java.lang.String family,
                                                           java.lang.String style)

Returns the point sizes of a font that has family family and style style that will look attractive. The list may be empty. For non-scalable fonts and bitmap scalable fonts, this function is equivalent to pointSizes.

See Also:
pointSizes, standardSizes

styleString

public final java.lang.String styleString(QFont font)

Returns a string that describes the style of the font. For example, "Bold Italic", "Bold", "Italic" or "Normal". An empty string may be returned.


styleString

public final java.lang.String styleString(QFontInfo fontInfo)

Returns a string that describes the style of the fontInfo. For example, "Bold Italic", "Bold", "Italic" or "Normal". An empty string may be returned.


styles

public final java.util.List<java.lang.String> styles(java.lang.String family)

Returns a list of the styles available for the font family family. Some example styles: "Light", "Light Italic", "Bold", "Oblique", "Demi". The list may be empty.

See Also:
families

weight

public final int weight(java.lang.String family,
                        java.lang.String style)

Returns the weight of the font that has family family and style style. If there is no such family and style combination, returns -1.

See Also:
italic, bold

writingSystems

public final java.util.List<QFontDatabase.WritingSystem> writingSystems(java.lang.String family)

Returns a sorted list of the writing systems supported by a given font family.

See Also:
families

writingSystems

public final java.util.List<QFontDatabase.WritingSystem> writingSystems()

Returns a sorted list of the available writing systems. This is list generated from information about all installed fonts on the system.

See Also:
families

addApplicationFont

public static int addApplicationFont(java.lang.String fileName)

Loads the font from the file specified by fileName and makes it available to the application. An ID is returned that can be used to remove the font again with removeApplicationFont or to retrieve the list of family names contained in the font.

The function returns -1 if the font could not be loaded.

Currently only TrueType fonts and TrueType font collections are supported.

Note: Adding application fonts on Unix/X11 platforms without fontconfig is currently not supported.

See Also:
addApplicationFontFromData, applicationFontFamilies, removeApplicationFont

addApplicationFontFromData

public static int addApplicationFontFromData(QByteArray fontData)

Loads the font from binary data specified by fontData and makes it available to the application. An ID is returned that can be used to remove the font again with removeApplicationFont or to retrieve the list of family names contained in the font.

The function returns -1 if the font could not be loaded.

Currently only TrueType fonts and TrueType font collections are supported.

Note: Adding application fonts on Unix/X11 platforms without fontconfig is currently not supported.

See Also:
addApplicationFont, applicationFontFamilies, removeApplicationFont

applicationFontFamilies

public static java.util.List<java.lang.String> applicationFontFamilies(int id)

Returns a list of font families for the given application font identified by id.

See Also:
addApplicationFont, addApplicationFontFromData

removeAllApplicationFonts

public static boolean removeAllApplicationFonts()

Removes all application-local fonts previously added using addApplicationFont and addApplicationFontFromData.

Returns true if unloading of the fonts succeeded; otherwise returns false.

See Also:
removeApplicationFont, addApplicationFont, addApplicationFontFromData

removeApplicationFont

public static boolean removeApplicationFont(int id)

Removes the previously loaded application font identified by id. Returns true if unloading of the font succeeded; otherwise returns false.

See Also:
removeAllApplicationFonts, addApplicationFont, addApplicationFontFromData

standardSizes

public static java.util.List<java.lang.Integer> standardSizes()

Returns a list of standard font sizes.

See Also:
smoothSizes, pointSizes

writingSystemName

public static java.lang.String writingSystemName(QFontDatabase.WritingSystem writingSystem)

Returns the names the writingSystem (e.g. for displaying to the user in a dialog).


writingSystemSample

public static java.lang.String writingSystemSample(QFontDatabase.WritingSystem writingSystem)

Returns a string with sample characters from writingSystem.


fromNativePointer

public static QFontDatabase fromNativePointer(QNativePointer nativePointer)
This function returns the QFontDatabase instance pointed to by nativePointer

Parameters:
nativePointer - the QNativePointer of which object should be returned.

nativePointerArray

public static QNativePointer nativePointerArray(QFontDatabase[] array)
This function returns a QNativePointer that is pointing to the specified QFontDatabase array.

Parameters:
array - the array that the returned pointer will point to.
Returns:
a QNativePointer that is pointing to the specified array.