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## com.trolltech.qt.core
Class QMimeData

    java.lang.Object
      com.trolltech.qt.internal.QSignalEmitterInternal
          com.trolltech.qt.QSignalEmitter
              com.trolltech.qt.QtJambiObject
                  com.trolltech.qt.core.QObject
                      com.trolltech.qt.core.QMimeData

All Implemented Interfaces:
  QtJambiInterface

    public class QMimeData

extends QObject

The QMimeData class provides a container for data that records information about its MIME type. QMimeData is used to describe information that can be stored in the `clipboard`, and transferred via the drag and drop mechanism. QMimeData objects associate the data that they hold with the corresponding MIME types to ensure that information can be safely transferred between applications, and copied around within the same application.

QMimeData objects are usually created using `new` and supplied to `QDrag` or `QClipboard` objects. This is to enable Qt to manage the memory that they use.

A single QMimeData object can store the same data using several different formats at the same time. The `formats()` function returns a list of the available formats in order of preference. The `data()` function returns the raw data associated with a MIME type, and `setData()` allows you to set the data for a MIME type.

For the most common MIME types, QMimeData provides convenience functions to access the data:

Tester | Getter | Setter | MIME Types
--- | --- | --- | ---
`hasText()` | `text()` | `setText()` | `text/plain`
`hasHtml()` | `html()` | `setHtml()` | `text/html`
`hasUrls()` | `urls()` | `setUrls()` | `text/uri-list`
`hasImage()` | `imageData()` | `setImageData()` | `image/` *
`hasColor()` | `colorData()` | `setColorData()` | `application/x-color`

For example, if your write a widget that accepts URL drags, you would end up writing code like this:
The following code example is written in c++.

    void MyWidget::dragEnterEvent(QDragEnterEvent *event)
    {
        if (event->mimeData()->hasUrls())
            event->acceptProposedAction();
    }

    void MyWidget::dropEvent(QDropEvent *event)
    {
        if (event->mimeData()->hasUrls()) {
            foreach (QUrl url, event->mimeData()->urls()) {
                ...
            }
        }
    }

There are three approaches for storing custom data in a QMimeData object:

1. Custom data can be stored directly in a QMimeData object as a `QByteArray` using `setData()`. For example:
   The following code example is written in c++.

       QByteArray csvData = ...;

       QMimeData *mimeData = new QMimeData;
       mimeData->setData("text/csv", csvData);

2. We can subclass QMimeData and reimplement `hasFormat()`, `formats()`, and `retrieveData()`.
3. If the drag and drop operation occurs withing a single application, we can subclass QMimeData and add extra data in it, and use a qobject_cast() in the receiver's drop event handler. For example:
   The following code example is written in c++.

       void MyWidget::dropEvent(QDropEvent *event)
       {
           const MyMimeData *myData =
                   qobject_cast<const MyMimeData *>(event->mimeData());
           if (myData) {
               // access myData's data directly (not through QMimeData's API)
           }
       }

## Platform-Specific MIME Types

On Windows, `formats()` will also return custom formats available in the MIME data, using the `x-qt-windows-mime` subtype to indicate that they represent data in non-standard formats. The formats will take the following form:
The following code example is written in c++.

    application/x-qt-windows-mime;value="<custom type>"

The following are examples of custom MIME types:
The following code example is written in c++.

    application/x-qt-windows-mime;value="FileGroupDescriptor"
    application/x-qt-windows-mime;value="FileContents"

The `value` declaration of each format describes the way in which the data is encoded.

On Windows, the MIME format does not always map directly to the clipboard formats. Qt provides QWindowsMime to map clipboard formats to open-standard MIME formats. Similarly, the QMacPasteboardMime maps MIME to Mac flavors.

See also:
  `QClipboard`, `QDragEnterEvent`, `QDragMoveEvent`, `QDropEvent`, `QDrag`, QWindowsMime, QMacPasteboardMime, and Drag and Drop.

Nested Class Summary

Nested classes/interfaces inherited from class com.trolltech.qt.QSignalEmitter
`QSignalEmitter.AbstractSignal, QSignalEmitter.Signal0, QSignalEmitter.Signal1, QSignalEmitter.Signal2, QSignalEmitter.Signal3, QSignalEmitter.Signal4, QSignalEmitter.Signal5, QSignalEmitter.Signal6, QSignalEmitter.Signal7, QSignalEmitter.Signal8, QSignalEmitter.Signal9`

Nested classes/interfaces inherited from class com.trolltech.qt.internal.QSignalEmitterInternal
`com.trolltech.qt.internal.QSignalEmitterInternal.AbstractSignalInternal`

Field Summary

Fields inherited from class com.trolltech.qt.internal.QSignalEmitterInternal
`currentSender`

Constructor Summary
`QMimeData()` Constructs a new MIME data object with no data in it.

Method Summary
`void` | `clear()` Removes all the MIME type and data entries in the object.
`java.lang.Object` | `colorData()` Returns a color if the data stored in the object represents a color (MIME type `application/x-color`); otherwise returns a null variant.
`QByteArray` | `data(java.lang.String mimetype)` Returns the data stored in the object in the format described by the MIME type specified by `mimeType`.
`java.util.List` | `formats()` Returns a list of formats supported by the object.
`boolean` | `hasColor()` Returns true if the object can return a color (MIME type `application/x-color`); otherwise returns false.
`boolean` | `hasFormat(java.lang.String mimetype)` Returns true if the object can return data for the MIME type specified by `mimeType`; otherwise returns false.
`boolean` | `hasHtml()` Returns true if the object can return HTML (MIME type `text/html`); otherwise returns false.
`boolean` | `hasImage()` Returns true if the object can return an image; otherwise returns false.
`boolean` | `hasText()` Returns true if the object can return plain text (MIME type `text/plain`); otherwise returns false.
`boolean` | `hasUrls()` Returns true if the object can return a list of urls; otherwise returns false.
`java.lang.String` | `html()` Returns a string if the data stored in the object is HTML (MIME type `text/html`); otherwise returns an empty string.
`java.lang.Object` | `imageData()` Returns a `QVariant` storing a `QImage` if the object can return an image; otherwise returns a null variant.
`void` | `removeFormat(java.lang.String mimetype)` Removes the data entry for `mimeType` in the object.
`protected java.lang.Object` | `retrieveData(java.lang.String mimetype, int preferredType)` Returns a variant with the given `type` containing data for the MIME type specified by `mimeType`.
`void` | `setColorData(java.lang.Object color)` Sets the color data in the object to the given `color`.
`void` | `setData(java.lang.String mimetype, QByteArray data)` Sets the data associated with the MIME type given by `mimeType` to the specified `data`.
`void` | `setHtml(java.lang.String html)` Sets `html` as the HTML (MIME type `text/html`) used to represent the data.
`void` | `setImageData(java.lang.Object image)` Sets the data in the object to the given `image`.
`void` | `setText(java.lang.String text)` Sets `text` as the plain text (MIME type `text/plain`) used to represent the data.
`void` | `setUrls(java.util.List urls)` Sets the URLs stored in the MIME data object to those specified by `urls`.
`java.lang.String` | `text()` Returns a plain text (MIME type `text/plain`) representation of the data.
`java.util.List` | `urls()` Returns a list of URLs contained within the MIME data object.

Methods inherited from class com.trolltech.qt.core.QObject
`childEvent, children, connectSlotsByName, customEvent, disposeLater, dumpObjectInfo, dumpObjectTree, dynamicPropertyNames, event, eventFilter, findChild, findChild, findChild, findChildren, findChildren, findChildren, findChildren, indexOfProperty, installEventFilter, isWidgetType, killTimer, moveToThread, objectName, parent, properties, property, removeEventFilter, setObjectName, setParent, setProperty, startTimer, timerEvent, toString, userProperty`

Methods inherited from class com.trolltech.qt.QtJambiObject
`dispose, disposed, equals, finalize, reassignNativeResources, tr, tr, tr`

Methods inherited from class com.trolltech.qt.QSignalEmitter
`blockSignals, disconnect, disconnect, signalsBlocked, signalSender, thread`

Methods inherited from class com.trolltech.qt.internal.QSignalEmitterInternal
`__qt_signalInitialization`

Methods inherited from class java.lang.Object
`clone, getClass, hashCode, notify, notifyAll, wait, wait, wait`

Methods inherited from interface com.trolltech.qt.QtJambiInterface
`disableGarbageCollection, nativeId, nativePointer, reenableGarbageCollection, setJavaOwnership`

Constructor Detail

### QMimeData

    public QMimeData()

  Constructs a new MIME data object with no data in it.

Method Detail

### clear

    public final void clear()

  Removes all the MIME type and data entries in the object.

### colorData

    public final java.lang.Object colorData()

  Returns a color if the data stored in the object represents a color (MIME type `application/x-color`); otherwise returns a null variant.

  A `QVariant` is used because QMimeData belongs to the QtCore library, whereas `QColor` belongs to QtGui. To convert the `QVariant` to a `QColor`, simply use qvariant_cast(). For example:
  The following code example is written in c++.

      if (event->mimeData()->hasColor()) {
          QColor color = qvariant_cast<QColor>(event->mimeData()->colorData());
          ...
      }

See also:
  `hasColor()`, `setColorData()`, and `data()`.

### data

    public final QByteArray data(java.lang.String mimetype)

  Returns the data stored in the object in the format described by the MIME type specified by `mimeType`.

See also:
  `setData()`.

### hasColor

    public final boolean hasColor()

  Returns true if the object can return a color (MIME type `application/x-color`); otherwise returns false.

See also:
  `setColorData()`, `colorData()`, and `hasFormat()`.

### hasHtml

    public final boolean hasHtml()

  Returns true if the object can return HTML (MIME type `text/html`); otherwise returns false.

See also:
  `setHtml()`, `html()`, and `hasFormat()`.

### hasImage

    public final boolean hasImage()

  Returns true if the object can return an image; otherwise returns false.

See also:
  `setImageData()`, `imageData()`, and `hasFormat()`.

### hasText

    public final boolean hasText()

  Returns true if the object can return plain text (MIME type `text/plain`); otherwise returns false.

See also:
  `setText()`, `text()`, `hasHtml()`, and `hasFormat()`.

### hasUrls

    public final boolean hasUrls()

  Returns true if the object can return a list of urls; otherwise returns false.

  URLs correspond to the MIME type `text/uri-list`.

See also:
  `setUrls()`, `urls()`, and `hasFormat()`.

### html

    public final java.lang.String html()

  Returns a string if the data stored in the object is HTML (MIME type `text/html`); otherwise returns an empty string.

See also:
  `setHtml()`, `hasHtml()`, and `setData()`.

### imageData

    public final java.lang.Object imageData()

  Returns a `QVariant` storing a `QImage` if the object can return an image; otherwise returns a null variant.

  A `QVariant` is used because QMimeData belongs to the QtCore library, whereas `QImage` belongs to QtGui. To convert the `QVariant` to a `QImage`, simply use qvariant_cast(). For example:
  The following code example is written in c++.

      if (event->mimeData()->hasImage()) {
          QImage image = qvariant_cast<QImage>(event->mimeData()->imageData());
          ...
      }

See also:
  `setImageData()`, and `hasImage()`.

### removeFormat

    public final void removeFormat(java.lang.String mimetype)

  Removes the data entry for `mimeType` in the object.

### setColorData

    public final void setColorData(java.lang.Object color)

  Sets the color data in the object to the given `color`.

  Colors correspond to the MIME type `application/x-color`.

See also:
  `colorData()`, `hasColor()`, and `setData()`.

### setData

    public final void setData(java.lang.String mimetype,
                              QByteArray data)

  Sets the data associated with the MIME type given by `mimeType` to the specified `data`.

  For the most common types of data, you can call the higher-level functions `setText()`, `setHtml()`, `setUrls()`, `setImageData()`, and `setColorData()` instead.

  Note that if you want to use a custom data type in an item view drag and drop operation, you must register it as a Qt meta type, using the Q_DECLARE_METATYPE() macro, and implement stream operators for it. The stream operators must then be registered with the qRegisterMetaTypeStreamOperators() function.

See also:
  `data()`, `hasFormat()`, QMetaType, and qRegisterMetaTypeStreamOperators().

### setHtml

    public final void setHtml(java.lang.String html)

  Sets `html` as the HTML (MIME type `text/html`) used to represent the data.

See also:
  `html()`, `hasHtml()`, `setText()`, and `setData()`.

### setImageData

    public final void setImageData(java.lang.Object image)

  Sets the data in the object to the given `image`.

  A `QVariant` is used because QMimeData belongs to the QtCore library, whereas `QImage` belongs to QtGui. The conversion from `QImage` to `QVariant` is implicit. For example:
  The following code example is written in c++.

      mimeData->setImageData(QImage("beautifulfjord.png"));

See also:
  `imageData()`, `hasImage()`, and `setData()`.

### setText

    public final void setText(java.lang.String text)

  Sets `text` as the plain text (MIME type `text/plain`) used to represent the data.

See also:
  `text()`, `hasText()`, `setHtml()`, and `setData()`.

### setUrls

    public final void setUrls(java.util.List urls)

  Sets the URLs stored in the MIME data object to those specified by `urls`.

  URLs correspond to the MIME type `text/uri-list`.

See also:
  `urls()`, `hasUrls()`, and `setData()`.

### text

    public final java.lang.String text()

  Returns a plain text (MIME type `text/plain`) representation of the data.

See also:
  `setText()`, `hasText()`, `html()`, and `data()`.

### urls

    public final java.util.List urls()

  Returns a list of URLs contained within the MIME data object.

  URLs correspond to the MIME type `text/uri-list`.

See also:
  `setUrls()`, `hasUrls()`, and `data()`.

### formats

    public java.util.List formats()

  Returns a list of formats supported by the object. This is a list of MIME types for which the object can return suitable data. The formats in the list are in a priority order.

  For the most common types of data, you can call the higher-level functions `hasText()`, `hasHtml()`, `hasUrls()`, `hasImage()`, and `hasColor()` instead.

See also:
  `hasFormat()`, `setData()`, and `data()`.

### hasFormat

    public boolean hasFormat(java.lang.String mimetype)

  Returns true if the object can return data for the MIME type specified by `mimeType`; otherwise returns false.

  For the most common types of data, you can call the higher-level functions `hasText()`, `hasHtml()`, `hasUrls()`, `hasImage()`, and `hasColor()` instead.

See also:
  `formats()`, `setData()`, and `data()`.

### retrieveData

    protected java.lang.Object retrieveData(java.lang.String mimetype,
                                            int preferredType)

  Returns a variant with the given `type` containing data for the MIME type specified by `mimeType`. If the object does not support the MIME type or variant type given, a null variant is returned instead.

  This function is called by the general `data()` getter and by the convenience getters (`text()`, `html()`, `urls()`, `imageData()`, and `colorData()`). You can reimplement it if you want to store your data using a custom data structure (instead of a `QByteArray`, which is what `setData()` provides). You would then also need to reimplement `hasFormat()` and `formats()`.

See also:
  `data()`.

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