QML Qt Element

The application object provides access to global application state properties shared by many QML components.

Its properties are:

The following example uses the application object to indicate whether the application is currently active:

 import QtQuick 1.1

 Rectangle {
     width: 300; height: 55
     color: Qt.application.active ? "white" : "lightgray"
     Text {
         text: "Application " + (Qt.application.active ? "active" : "inactive")
         opacity: Qt.application.active ? 1.0 : 0.5
         anchors.centerIn: parent
     }
 }

This property group was introduced in QtQuick 1.1.

ASCII to binary - this function returns a base64 decoding of data.

Binary to ASCII - this function returns a base64 encoding of data.

Returns a Component object created using the QML file at the specified url, or null if an empty string was given.

The returned component's Component::status property indicates whether the component was successfully created. If the status is Component.Error, see Component::errorString() for an error description.

Call Component.createObject() on the returned component to create an object instance of the component.

For example:

 import QtQuick 1.0

 Item {
     id: container
     width: 300; height: 300

     function loadButton() {
         var component = Qt.createComponent("Button.qml");
         if (component.status == Component.Ready) {
             var button = component.createObject(container);
             button.color = "red";
         }
     }

     Component.onCompleted: loadButton()
 }

See Dynamic Object Management in QML for more information on using this function.

To create a QML object from an arbitrary string of QML (instead of a file), use Qt.createQmlObject().

Returns a new object created from the given string of QML which will have the specified parent, or null if there was an error in creating the object.

If filepath is specified, it will be used for error reporting for the created object.

Example (where parentItem is the id of an existing QML item):

 var newObject = Qt.createQmlObject('import QtQuick 1.0; Rectangle {color: "red"; width: 20; height: 20}',
     parentItem, "dynamicSnippet1");

In the case of an error, a QtScript Error object is thrown. This object has an additional property, qmlErrors, which is an array of the errors encountered. Each object in this array has the members lineNumber, columnNumber, fileName and message. For example, if the above snippet had misspelled color as 'colro' then the array would contain an object like the following: { "lineNumber" : 1, "columnNumber" : 32, "fileName" : "dynamicSnippet1", "message" : "Cannot assign to non-existent property "colro""}.

Note that this function returns immediately, and therefore may not work if the qml string loads new components (that is, external QML files that have not yet been loaded). If this is the case, consider using Qt.createComponent() instead.

See Dynamic Object Management in QML for more information on using this function.

Returns a color darker than baseColor by the factor provided.

If the factor is greater than 1.0, this function returns a darker color. Setting factor to 3.0 returns a color that has one-third the brightness. If the factor is less than 1.0, the return color is lighter, but we recommend using the Qt.lighter() function for this purpose. If the factor is 0 or negative, the return value is unspecified.

The function converts the current RGB color to HSV, divides the value (V) component by factor and converts the color back to RGB.

If factor is not supplied, returns a color 50% darker than baseColor (factor 2.0).

Returns a list of the font families available to the application.

Returns a string representation of date, optionally formatted according to format.

The date parameter may be a JavaScript Date object, a date property, a QDate, or QDateTime value. The format parameter may be any of the possible format values as described for Qt.formatDateTime().

If format is not specified, date is formatted using Qt.DefaultLocaleShortDate.

Returns a string representation of datetime, optionally formatted according to format.

The date parameter may be a JavaScript Date object, a date property, a QDate, QTime, or QDateTime value.

If format is not provided, dateTime is formatted using Qt.DefaultLocaleShortDate. Otherwise, format should be either.

• One of the Qt::DateFormat enumeration values, such as Qt.DefaultLocaleShortDate or Qt.ISODate
• A string that specifies the format of the returned string, as detailed below.

If format specifies a format string, it should use the following expressions to specify the date:

In addition the following expressions can be used to specify the time:

All other input characters will be ignored. Any sequence of characters that are enclosed in single quotes will be treated as text and not be used as an expression. Two consecutive single quotes ("''") are replaced by a single quote in the output.

For example, if the following date/time value was specified:

 // 21 May 2001 14:13:09
 var dateTime = new Date(2001, 5, 21, 14, 13, 09)

This dateTime value could be passed to Qt.formatDateTime(), Qt.formatDate() or Qt.formatTime() with the format values below to produce the following results:

Returns a string representation of time, optionally formatted according to format.

The time parameter may be a JavaScript Date object, a QTime, or QDateTime value. The format parameter may be any of the possible format values as described for Qt.formatDateTime().

If format is not specified, time is formatted using Qt.DefaultLocaleShortDate.

Returns a color with the specified hue, saturation, lightness and alpha components. All components should be in the range 0-1 inclusive.

Includes another JavaScript file. This method can only be used from within JavaScript files, and not regular QML files.

This imports all functions from url into the current script's namespace.

Qt.include() returns an object that describes the status of the operation. The object has a single property, status, that is set to one of the following values:

The status property will be updated as the operation progresses.

If provided, callback is invoked when the operation completes. The callback is passed the same object as is returned from the Qt.include() call.

Returns true if object is a valid reference to a Qt or QML object, otherwise false.

Returns a color lighter than baseColor by the factor provided.

If the factor is greater than 1.0, this functions returns a lighter color. Setting factor to 1.5 returns a color that is 50% brighter. If the factor is less than 1.0, the return color is darker, but we recommend using the Qt.darker() function for this purpose. If the factor is 0 or negative, the return value is unspecified.

The function converts the current RGB color to HSV, multiplies the value (V) component by factor and converts the color back to RGB.

If factor is not supplied, returns a color 50% lighter than baseColor (factor 1.5).

Returns a hex string of the md5 hash of data.

Attempts to open the specified target url in an external application, based on the user's desktop preferences. Returns true if it succeeds, and false otherwise.

Returns a Point with the specified x and y coordinates.

This function causes the QDeclarativeEngine::quit() signal to be emitted. Within the QML Viewer, this causes the launcher application to exit; to quit a C++ application when this method is called, connect the QDeclarativeEngine::quit() signal to the QCoreApplication::quit() slot.

Returns a rect with the top-left corner at x, y and the specified width and height.

The returned object has x, y, width and height attributes with the given values.

Returns url resolved relative to the URL of the caller.

Returns a color with the specified red, green, blue and alpha components. All components should be in the range 0-1 inclusive.

Returns a Size with the specified width and height.

This function allows tinting one color with another.

The tint color should usually be mostly transparent, or you will not be able to see the underlying color. The below example provides a slight red tint by having the tint color be pure red which is only 1/16th opaque.

 Item {
     Rectangle {
         x: 0; width: 80; height: 80
         color: "lightsteelblue"
     }
     Rectangle {
         x: 100; width: 80; height: 80
         color: Qt.tint("lightsteelblue", "#10FF0000")
     }
 }

Tint is most useful when a subtle change is intended to be conveyed due to some event; you can then use tinting to more effectively tune the visible color.

Returns a Vector3D with the specified x, y and z.