source: trunk/src/gui/kernel/qdnd_x11.cpp@ 142

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#include "qplatformdefs.h"

#include "qapplication.h"

#ifndef QT_NO_DRAGANDDROP

#include "qwidget.h"
#include "qpainter.h"
#include "qpixmap.h"
#include "qbitmap.h"
#include "qdesktopwidget.h"
#include "qevent.h"
#include "qdatetime.h"
#include "qiodevice.h"
#include "qpointer.h"
#include "qcursor.h"
#include "qvariant.h"
#include "qvector.h"
#include "qurl.h"
#include "qdebug.h"
#include "qimagewriter.h"
#include "qbuffer.h"
#include "qtextcodec.h"

#include "qdnd_p.h"
#include "qt_x11_p.h"
#include "qx11info_x11.h"

#include "qwidget_p.h"
#include "qcursor_p.h"

QT_BEGIN_NAMESPACE

// #define DND_DEBUG
#ifdef DND_DEBUG
#define DEBUG qDebug
#else
#define DEBUG if(0) qDebug
#endif

#ifdef DND_DEBUG
#define DNDDEBUG qDebug()
#else
#define DNDDEBUG if(0) qDebug()
#endif

static int findXdndDropTransactionByWindow(Window window)
{
    int at = -1;
    for (int i = 0; i < X11->dndDropTransactions.count(); ++i) {
        const QXdndDropTransaction &t = X11->dndDropTransactions.at(i);
        if (t.target == window || t.proxy_target == window) {
            at = i;
            break;
        }
    }
    return at;
}

static int findXdndDropTransactionByTime(Time timestamp)
{
    int at = -1;
    for (int i = 0; i < X11->dndDropTransactions.count(); ++i) {
        const QXdndDropTransaction &t = X11->dndDropTransactions.at(i);
        if (t.timestamp == timestamp) {
            at = i;
            break;
        }
    }
    return at;
}

// timer used to discard old XdndDrop transactions
static int transaction_expiry_timer = -1;
enum { XdndDropTransactionTimeout = 5000 }; // 5 seconds

static void restartXdndDropExpiryTimer()
{
    if (transaction_expiry_timer != -1)
        QDragManager::self()->killTimer(transaction_expiry_timer);
    transaction_expiry_timer = QDragManager::self()->startTimer(XdndDropTransactionTimeout);
}


// find an ancestor with XdndAware on it
static Window findXdndAwareParent(Window window)
{
    Window target = 0;
    forever {
        // check if window has XdndAware
        Atom type = 0;
        int f;
        unsigned long n, a;
        unsigned char *data = 0;
        if (XGetWindowProperty(X11->display, window, ATOM(XdndAware), 0, 0, False,
                               AnyPropertyType, &type, &f,&n,&a,&data) == Success) {
            if (data)
                XFree(data);
            if (type) {
                target = window;
                break;
            }
        }

        // try window's parent
        Window root;
        Window parent;
        Window *children;
        uint unused;
        if (!XQueryTree(X11->display, window, &root, &parent, &children, &unused))
            break;
        if (children)
            XFree(children);
        if (window == root)
            break;
        window = parent;
    }
    return target;
}




// and all this stuff is copied -into- qapp_x11.cpp

static void handle_xdnd_position(QWidget *, const XEvent *, bool);
static void handle_xdnd_status(QWidget * w, const XEvent * xe, bool /*passive*/);

const int xdnd_version = 5;

static Qt::DropAction xdndaction_to_qtaction(Atom atom)
{
    if (atom == ATOM(XdndActionCopy) || atom == 0)
        return Qt::CopyAction;
    if (atom == ATOM(XdndActionLink))
        return Qt::LinkAction;
    if (atom == ATOM(XdndActionMove))
        return Qt::MoveAction;
    return Qt::CopyAction;
}

static int qtaction_to_xdndaction(Qt::DropAction a)
{
    switch (a) {
    case Qt::CopyAction:
        return ATOM(XdndActionCopy);
    case Qt::LinkAction:
        return ATOM(XdndActionLink);
    case Qt::MoveAction:
    case Qt::TargetMoveAction:
        return ATOM(XdndActionMove);
    case Qt::IgnoreAction: