java.awt.dnd: public class: DropTargetDragEvent

java.awt.dnd
public class: DropTargetDragEvent [javadoc | source]

java.lang.Object
   java.util.EventObject
      java.awt.dnd.DropTargetEvent
         java.awt.dnd.DropTargetDragEvent

All Implemented Interfaces:
Serializable

The DropTargetDragEvent is delivered to a DropTargetListener via its dragEnter() and dragOver() methods.

The DropTargetDragEvent reports the source drop actions and the user drop action that reflect the current state of the drag operation.

Source drop actions is a bitwise mask of DnDConstants that represents the set of drop actions supported by the drag source for this drag operation.

User drop action depends on the drop actions supported by the drag source and the drop action selected by the user. The user can select a drop action by pressing modifier keys during the drag operation:

Ctrl + Shift -> ACTION_LINK
Ctrl -> ACTION_COPY
Shift -> ACTION_MOVE

If the user selects a drop action, the user drop action is one of DnDConstants that represents the selected drop action if this drop action is supported by the drag source or DnDConstants.ACTION_NONE if this drop action is not supported by the drag source.

If the user doesn't select a drop action, the set of DnDConstants that represents the set of drop actions supported by the drag source is searched for DnDConstants.ACTION_MOVE, then for DnDConstants.ACTION_COPY, then for DnDConstants.ACTION_LINK and the user drop action is the first constant found. If no constant is found the user drop action is DnDConstants.ACTION_NONE.

since: 1.2 -

Fields inherited from java.awt.dnd.DropTargetEvent:
context

Fields inherited from java.util.EventObject:
source

Constructor:

Constructor:
public DropTargetDragEvent(DropTargetContext dtc, Point cursorLocn, int dropAction, int srcActions) { super(dtc); if (cursorLocn == null) throw new NullPointerException("cursorLocn"); if (dropAction != DnDConstants.ACTION_NONE && dropAction != DnDConstants.ACTION_COPY && dropAction != DnDConstants.ACTION_MOVE && dropAction != DnDConstants.ACTION_LINK ) throw new IllegalArgumentException("dropAction" + dropAction); if ((srcActions & ~(DnDConstants.ACTION_COPY_OR_MOVE \| DnDConstants.ACTION_LINK)) != 0) throw new IllegalArgumentException("srcActions"); location = cursorLocn; actions = srcActions; this.dropAction = dropAction; } Construct a `DropTargetDragEvent` given the `DropTargetContext` for this operation, the location of the "Drag" `Cursor`'s hotspot in the `Component`'s coordinates, the user drop action, and the source drop actions. Parameters: `dtc` - The DropTargetContext for this operation `cursorLocn` - The location of the "Drag" Cursor's hotspot in Component coordinates `dropAction` - The user drop action `srcActions` - The source drop actions Throws: `NullPointerException` - if cursorLocn is null `<` - code>IllegalArgumentException if dropAction is not one of `DnDConstants`. `<` - code>IllegalArgumentException if srcActions is not a bitwise mask of `DnDConstants`. `<` - code>IllegalArgumentException if dtc is `null`.

 public DropTargetDragEvent(DropTargetContext dtc,
    Point cursorLocn,
    int dropAction,
    int srcActions) {
                                                                                                                             
        super(dtc);
        if (cursorLocn == null) throw new NullPointerException("cursorLocn");
        if (dropAction != DnDConstants.ACTION_NONE &&
            dropAction != DnDConstants.ACTION_COPY &&
            dropAction != DnDConstants.ACTION_MOVE &&
            dropAction != DnDConstants.ACTION_LINK
        ) throw new IllegalArgumentException("dropAction" + dropAction);
        if ((srcActions & ~(DnDConstants.ACTION_COPY_OR_MOVE | DnDConstants.ACTION_LINK)) != 0) throw new IllegalArgumentException("srcActions");
        location        = cursorLocn;
        actions         = srcActions;
        this.dropAction = dropAction;
}

DropTargetDragEvent

DropTargetContext

Cursor

Component

Parameters:

dtc - The DropTargetContext for this operation

cursorLocn - The location of the "Drag" Cursor's hotspot in Component coordinates

dropAction - The user drop action

srcActions - The source drop actions

Throws:

NullPointerException - if cursorLocn is null

< - code>IllegalArgumentException if dropAction is not one of DnDConstants.

< - code>IllegalArgumentException if srcActions is not a bitwise mask of DnDConstants.

< - code>IllegalArgumentException if dtc is null.

Method from java.awt.dnd.DropTargetDragEvent Summary:
acceptDrag, getCurrentDataFlavors, getCurrentDataFlavorsAsList, getDropAction, getLocation, getSourceActions, getTransferable, isDataFlavorSupported, rejectDrag

Methods from java.awt.dnd.DropTargetEvent:
getDropTargetContext

Methods from java.util.EventObject:
getSource, toString

Methods from java.lang.Object:
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method from java.awt.dnd.DropTargetDragEvent Detail:
public void acceptDrag(int dragOperation) { getDropTargetContext().acceptDrag(dragOperation); } Accepts the drag. This method should be called from a `DropTargetListeners` `dragEnter`, `dragOver`, and `dropActionChanged` methods if the implementation wishes to accept an operation from the srcActions other than the one selected by the user as represented by the `dropAction`.
public DataFlavor[] getCurrentDataFlavors() { return getDropTargetContext().getCurrentDataFlavors(); } This method returns the current `DataFlavor`s from the `DropTargetContext`.
public List getCurrentDataFlavorsAsList() { return getDropTargetContext().getCurrentDataFlavorsAsList(); } This method returns the current `DataFlavor`s as a `java.util.List`
public int getDropAction() { return dropAction; } This method returns the user drop action.
public Point getLocation() { return location; } This method returns a `Point` indicating the `Cursor`'s current location within the `Component'`s coordinates.
public int getSourceActions() { return actions; } This method returns the source drop actions.
public Transferable getTransferable() { return getDropTargetContext().getTransferable(); } This method returns the Transferable object that represents the data associated with the current drag operation.
public boolean isDataFlavorSupported(DataFlavor df) { return getDropTargetContext().isDataFlavorSupported(df); } This method returns a `boolean` indicating if the specified `DataFlavor` is supported.
public void rejectDrag() { getDropTargetContext().rejectDrag(); } Rejects the drag as a result of examining either the `dropAction` or the available `DataFlavor` types.

Method from java.awt.dnd.DropTargetDragEvent Detail:

 public  void acceptDrag(int dragOperation) {
        getDropTargetContext().acceptDrag(dragOperation);
}

DropTargetListeners

dragEnter

dragOver

dropActionChanged

dropAction

 public DataFlavor[] getCurrentDataFlavors() {
        return getDropTargetContext().getCurrentDataFlavors();
}

DataFlavor

DropTargetContext

 public List getCurrentDataFlavorsAsList() {
        return getDropTargetContext().getCurrentDataFlavorsAsList();
}

DataFlavor

java.util.List

 public int getDropAction() {
 return dropAction;
}

This method returns the user drop action.

 public Point getLocation() {
        return location;
}

Point

Cursor

Component'

 public int getSourceActions() {
 return actions;
}

This method returns the source drop actions.

 public Transferable getTransferable() {
        return getDropTargetContext().getTransferable();
}

This method returns the Transferable object that represents the data associated with the current drag operation.

 public boolean isDataFlavorSupported(DataFlavor df) {
        return getDropTargetContext().isDataFlavorSupported(df);
}

boolean

DataFlavor

 public  void rejectDrag() {
        getDropTargetContext().rejectDrag();
}

dropAction

DataFlavor