Ticket #3600: 3600-Make-it-possible-to-drag-dialogs.patch

lib/widget/dialog.c

@@ -41 +41 @@
 #include "lib/tty/key.h"
 #include "lib/strutil.h"
 #include "lib/widget.h"
+#include "lib/widget/mouse.h"
 #include "lib/fileloc.h"        /* MC_HISTORY_FILE */
 #include "lib/event.h"          /* mc_event_raise() */
 
@@ -355 +356 @@
     return MSG_NOT_HANDLED;
 }
 
+
 /* --------------------------------------------------------------------------------------------- */
 
 static int
 dlg_mouse_event (WDialog * h, Gpm_Event * event)
 {
     Widget *wh = WIDGET (h);
+    gboolean mouse_post_processing = ((h->flags & DLG_MOUSE_POST_PROCESSING) != 0);
 
     GList *p, *first;
 
@@ -373 +376 @@
         return MOU_NORMAL;
     }
 
-    if (wh->mouse != NULL)
+    if (!mouse_post_processing && wh->mouse != NULL)
     {
         int mou;
 
@@ -403 +406 @@
     }
     while (p != first);
 
+    if (mouse_post_processing && wh->mouse != NULL)
+    {
+        int mou;
+
+        mou = wh->mouse (event, wh);
+        if (mou != MOU_UNHANDLED)
+            return mou;
+    }
+
     return MOU_UNHANDLED;
 }
 
@@ -604 +616 @@
 
     tty_setcolor (h->color[DLG_COLOR_NORMAL]);
     dlg_erase (h);
+    if (h->is_dragging)
+    {
+        /* Give feedback to the user when dragging.
+         *
+         * @FIXME: Have skins define a dedicated color for dragging. We pick
+         * 'dtitle' because there doesn't seem to be something better.
+         * @TODO: Make WHLine too use this color (when owner is dragged). */
+        tty_setcolor (h->color[DLG_COLOR_TITLE]);
+    }
     tty_draw_box (wh->y + space, wh->x + space, wh->lines - 2 * space, wh->cols - 2 * space, FALSE);
 
     if (h->title != NULL)
@@ -769 +790 @@
 }
 
 /* --------------------------------------------------------------------------------------------- */
+/**
+ * Default dialog mouse callback
+ *
+ * It lets you drag the dialog by dragging any "empty" space in it (any space
+ * that doesn't respond to the mouse, to be exact).
+ */
+
+static void
+dlg_default_mouse_callback (Widget * w, mouse_msg_t msg, mouse_event_t * event)
+{
+    WDialog *h = DIALOG (w);
+    static int drag_start_x, drag_start_y;
+
+    if (!h->fullscreen)
+    {
+        switch (msg)
+        {
+        case MSG_MOUSE_DOWN:
+            h->is_dragging = TRUE;
+            drag_start_x = event->x;
+            drag_start_y = event->y;
+            /* Update the dialog frame (and, in future, HLines) so user sees feedback: */
+            do_refresh ();      /* FIXME: why doesn't `widget_redraw (w)` work? No need to paint the whole screen. */
+            break;
+        case MSG_MOUSE_UP:
+            h->is_dragging = FALSE;
+            /* Update the dialog frame: */
+            do_refresh ();
+            break;
+        case MSG_MOUSE_DRAG:
+            /* The is_idle() check isn't mandatory. It just prevents sluggish
+             * drag when the dialogs beneath are CPU-intensive to draw. */
+            if (is_idle ())
+            {
+                dlg_move (h, w->x + (event->x - drag_start_x), w->y + (event->y - drag_start_y));
+                do_refresh ();  /* Draw the whole screen. */
+            }
+            break;
+        default:
+            break;
+        }
+    }
+}
+
+/* --------------------------------------------------------------------------------------------- */
 
 WDialog *
 dlg_create (gboolean modal, int y1, int x1, int lines, int cols,
@@ -784 +850 @@
                  mouse_handler);
     widget_want_cursor (w, FALSE);
 
+    if (mouse_handler == NULL)
+    {
+        set_easy_mouse_callback (w, dlg_default_mouse_callback);
+        flags |= DLG_MOUSE_POST_PROCESSING;
+    }
+
     new_d->state = DLG_CONSTRUCT;
     new_d->modal = modal;
     new_d->color = colors;
     new_d->help_ctx = help_ctx;
     new_d->flags = flags;
+    new_d->is_dragging = FALSE;
     new_d->data = NULL;
 
     dlg_set_size (new_d, lines, cols);
@@ -1289 +1362 @@
 /* --------------------------------------------------------------------------------------------- */
 
 /**
+ * Moves a dialog to (x, y).
+ *
+ * We need to traverse the child widgets as well because their coordinates
+ * are in aboslute screen coordinates.
+ */
+void
+dlg_move (WDialog * h, int x, int y)
+{
+    Widget *wh = WIDGET (h);
+    int dx, dy;
+
+    dx = x - wh->x;
+    dy = y - wh->y;
+
+    wh->x = x;
+    wh->y = y;
+
+    {
+        GList *w;
+
+        for (w = h->widgets; w != NULL; w = g_list_next (w))
+        {
+            /* FIXME: exclude the WButtonBar (as in the Help dialog). */
+            WIDGET (w->data)->x += dx;
+            WIDGET (w->data)->y += dy;
+        }
+    }
+}
+
+/* --------------------------------------------------------------------------------------------- */
+
+/**
   * Write history to the ${XDG_CACHE_HOME}/mc/history file
   */
 void

lib/widget/dialog.h

@@ -37 +37 @@
     DLG_CENTER = (1 << 0),      /* Center the dialog */
     DLG_TRYUP = (1 << 1),       /* Try to move two lines up the dialog */
     DLG_COMPACT = (1 << 2),     /* Suppress spaces around the frame */
-    DLG_WANT_TAB = (1 << 3)     /* Should the tab key be sent to the dialog? */
+    DLG_WANT_TAB = (1 << 3),    /* Should the tab key be sent to the dialog? */
+    DLG_MOUSE_POST_PROCESSING = (1 << 4)        /* Whether mouse events are handed to the dialog *after* child widgets see them (instead of before). */
 } dlg_flags_t;
 
 /* Dialog state */
@@ -94 +95 @@
     dlg_state_t state;
     gboolean fullscreen;        /* Parents dialogs don't need refresh */
     gboolean winch_pending;     /* SIGWINCH signal has been got. Resize dialog after rise */
+    gboolean is_dragging;       /* Whether the dialog is being dragged. */
     int mouse_status;           /* For the autorepeat status of the mouse */
 
     /* Internal variables */
@@ -157 +159 @@
 
 void dlg_redraw (WDialog * h);
 
+void dlg_move (WDialog * h, int x, int y);
+
 void dlg_broadcast_msg (WDialog * h, widget_msg_t message);
 
 /* Default callback for dialogs */