qdnd_x11.cpp

奇趣公司比较新的qt/emd版本

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#include "qplatformdefs.h"

#include "qapplication.h"

#ifndef QT_NO_DRAGANDDROP

#include "qwidget.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"

// #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:
        return XNone;
    default:
        return ATOM(XdndActionCopy);
    }
}

// clean up the stuff used.
static void qt_xdnd_cleanup();

static void qt_xdnd_send_leave();

// real variables:
// xid of current drag source
static Atom qt_xdnd_dragsource_xid = 0;

// the types in this drop. 100 is no good, but at least it's big.
const int qt_xdnd_max_type = 100;
static Atom qt_xdnd_types[qt_xdnd_max_type + 1];

// timer used when target wants "continuous" move messages (eg. scroll)
static int heartbeat = -1;
// rectangle in which the answer will be the same
static QRect qt_xdnd_source_sameanswer;
// top-level window we sent position to last.
static Window qt_xdnd_current_target;
// window to send events to (always valid if qt_xdnd_current_target)
static Window qt_xdnd_current_proxy_target;
static Time qt_xdnd_source_current_time;

// widget we forwarded position to last, and local position
static QPointer<QWidget> qt_xdnd_current_widget;
static QPoint qt_xdnd_current_position;
// timestamp from the XdndPosition and XdndDrop
static Time qt_xdnd_target_current_time;
// screen number containing the pointer... -1 means default
static int qt_xdnd_current_screen = -1;
// state of dragging... true if dragging, false if not
bool qt_xdnd_dragging = false;

static bool waiting_for_status = false;

// used to preset each new QDragMoveEvent
static Qt::DropAction last_target_accepted_action = Qt::IgnoreAction;

// Shift/Ctrl handling, and final drop status
static Qt::DropAction global_accepted_action = Qt::CopyAction;
static Qt::DropActions possible_actions = Qt::IgnoreAction;

// for embedding only
static QWidget* current_embedding_widget  = 0;
static XEvent last_enter_event;

// cursors
static QCursor *noDropCursor = 0;
static QCursor *moveCursor = 0;
static QCursor *copyCursor = 0;
static QCursor *linkCursor = 0;

static QPixmap *defaultPm = 0;

static const int default_pm_hotx = -2;
static const int default_pm_hoty = -16;
static const char* const default_pm[] = {
"13 9 3 1",
".      c None",
"       c #000000",
"X      c #FFFFFF",
"X X X X X X X",
" X X X X X X ",
"X ......... X",
" X.........X ",
"X ......... X",
" X.........X ",
"X ......... X",
" X X X X X X ",
"X X X X X X X"
};

class QShapedPixmapWidget : public QWidget {

public:
    QShapedPixmapWidget(int screen = -1) :
        QWidget(QApplication::desktop()->screen(screen),
                Qt::Tool | Qt::FramelessWindowHint | Qt::X11BypassWindowManagerHint)
    {
    }

    void setPixmap(const QPixmap &pm)
    {
        QBitmap mask = pm.mask();
        if (!mask.isNull()) {
            setMask(mask);
        } else {
            clearMask();
        }
        resize(pm.width(),pm.height());
	QPalette p = palette();
	p.setBrush(backgroundRole(), QBrush(pm));
	setPalette(p);
        update();
    }
    QPoint pm_hot;
};

struct XdndData {
    QShapedPixmapWidget *deco;
    QWidget* desktop_proxy;
};

static XdndData xdnd_data = { 0, 0 };

class QExtraWidget : public QWidget
{
    Q_DECLARE_PRIVATE(QWidget)
public:
    inline QWExtra* extraData();
    inline QTLWExtra* topData();
};

inline QWExtra* QExtraWidget::extraData() { return d_func()->extraData(); }
inline QTLWExtra* QExtraWidget::topData() { return d_func()->topData(); }


static WId xdndProxy(WId w)
{
    Atom type = XNone;
    int f;
    unsigned long n, a;
    unsigned char *retval = 0;
    XGetWindowProperty(X11->display, w, ATOM(XdndProxy), 0, 1, False,
                       XA_WINDOW, &type, &f,&n,&a,&retval);
    WId *proxy_id_ptr = (WId *)retval;
    WId proxy_id = 0;
    if (type == XA_WINDOW && proxy_id_ptr) {
        proxy_id = *proxy_id_ptr;
        XFree(proxy_id_ptr);
        proxy_id_ptr = 0;
        // Already exists. Real?
        X11->ignoreBadwindow();
        XGetWindowProperty(X11->display, proxy_id, ATOM(XdndProxy), 0, 1, False,
                           XA_WINDOW, &type, &f,&n,&a,&retval);
        proxy_id_ptr = (WId *)retval;
        if (X11->badwindow() || type != XA_WINDOW || !proxy_id_ptr || *proxy_id_ptr != proxy_id)
            // Bogus - we will overwrite.
            proxy_id = 0;
    }
    if (proxy_id_ptr)
        XFree(proxy_id_ptr);
    return proxy_id;
}

static bool xdndEnable(QWidget* w, bool on)
{
    DNDDEBUG << "xdndEnable" << w << on;
    if (on) {
        QWidget * xdnd_widget = 0;
        if ((w->windowType() == Qt::Desktop)) {
            if (xdnd_data.desktop_proxy) // *WE* already have one.
                return false;

            // As per Xdnd4, use XdndProxy
            XGrabServer(X11->display);
            Q_ASSERT(w->testAttribute(Qt::WA_WState_Created));
            WId proxy_id = xdndProxy(w->internalWinId());

            if (!proxy_id) {
                xdnd_widget = xdnd_data.desktop_proxy = new QWidget;
                proxy_id = xdnd_data.desktop_proxy->internalWinId();
                XChangeProperty (X11->display, w->internalWinId(), ATOM(XdndProxy),
                                 XA_WINDOW, 32, PropModeReplace, (unsigned char *)&proxy_id, 1);
                XChangeProperty (X11->display, proxy_id, ATOM(XdndProxy),
                                 XA_WINDOW, 32, PropModeReplace, (unsigned char *)&proxy_id, 1);
            }

            XUngrabServer(X11->display);
        } else {
            xdnd_widget = w->window();
        }
        if (xdnd_widget) {
            DNDDEBUG << "setting XdndAware for" << xdnd_widget << xdnd_widget->internalWinId();
            Atom atm = (Atom)xdnd_version;
            Q_ASSERT(xdnd_widget->testAttribute(Qt::WA_WState_Created));
            XChangeProperty(X11->display, xdnd_widget->internalWinId(), ATOM(XdndAware),
                             XA_ATOM, 32, PropModeReplace, (unsigned char *)&atm, 1);
            return true;
        } else {
            return false;
        }
    } else {
        if ((w->windowType() == Qt::Desktop)) {
            XDeleteProperty(X11->display, w->internalWinId(), ATOM(XdndProxy));
            delete xdnd_data.desktop_proxy;
            xdnd_data.desktop_proxy = 0;
        } else {
            DNDDEBUG << "not deleting XDndAware";
        }
        return true;
    }
}

QByteArray QX11Data::xdndAtomToString(Atom a)
{
    if (!a) return 0;

    if (a == XA_STRING || a == ATOM(UTF8_STRING)) {
        return "text/plain"; // some Xdnd clients are dumb
    }
    char *atom = XGetAtomName(display, a);
    QByteArray result = atom;
    XFree(atom);
    return result;
}

Atom QX11Data::xdndStringToAtom(const char *mimeType)
{
    if (!mimeType || !*mimeType)
        return 0;
    return XInternAtom(display, mimeType, False);
}