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The QToolTip class provides tool tips (sometimes called balloon help) for any widget or rectangular part of a widget. More...
#include <qtooltip.h>
Inherits Qt.
The QToolTip class provides tool tips (sometimes called balloon help) for any widget or rectangular part of a widget.
The tip is a short, one-line text reminding the user of the widget's or rectangle's function. It is drawn immediately below the region in a distinctive black-on-yellow combination. In Motif style, Qt's tool tips look much like Motif's but feel more like Windows 95 tool tips.
QToolTipGroup provides a way for tool tips to display another text elsewhere (most often in a status bar).
At any point in time, QToolTip is either dormant or active. In dormant mode the tips are not shown and in active mode they are. The mode is global, not particular to any one widget.
QToolTip switches from dormant to active mode when the user lets the mouse rest on a tip-equipped region for a second or so and remains in active mode until the user either clicks a mouse button, presses a key, lets the mouse rest for five seconds or moves the mouse outside all tip-equipped regions for at least a second.
The QToolTip class can be used in three different ways:
To add a tip to a widget, call the static function QToolTip::add() with the widget and tip as arguments:
QToolTip::add( quitButton, "Leave the application" );
This is the simplest and most common use of QToolTip. The tip will be deleted automatically when quitButton is deleted, but you can remove it yourself, too:
QToolTip::remove( quitButton );
You can also display another text (typically in a status bar), courtesy of QToolTipGroup. This example
assumes that g is a QToolTipGroup *
and is already
connected to the appropriate status bar:
QToolTip::add( quitButton, "Leave the application", g, "Leave the application without asking for confirmation" ); QToolTip::add( closeButton, "Close this window", g, "Close this window without asking for confirmation" );
To add a tip to a fixed rectangle within a widget, call the static function QToolTip::add() with the widget, rectangle and tip as arguments. (See the tooltip/tooltip.cpp example.) Again, you can supply a QToolTipGroup * and another text if you want.
Both of these are one-liners and cover the vast majority of cases. The third and most general way to use QToolTip uses a pure virtual function to decide whether to pop up a tool tip. The tooltip/tooltip.cpp example demonstrates this, too. This mode can be used to implement tips for text that can move as the user scrolls, for example.
To use QToolTip like this, you need to subclass QToolTip and reimplement maybeTip(). QToolTip calls maybeTip() when a tip should pop up, and maybeTip decides whether to show a tip.
Tool tips can be globally disabled using QToolTip::setEnabled() or disabled in groups with QToolTipGroup::setEnabled().
See also QStatusBar, QWhatsThis, QToolTipGroup and GUI Design Handbook: Tool Tip.
widget is the widget you want to add dynamic tool tips to and group (optional) is the tool tip group they should belong to.
Warning: QToolTip is not a subclass of QObject, so the instance of QToolTip is not deleted when widget is deleted.
See also maybeTip().
This is the most common entry point to the QToolTip class; it is suitable for adding tool tips to buttons, check boxes, combo boxes and so on.
Examples: qdir/qdir.cpp, scribble/scribble.cpp and tooltip/tooltip.cpp.
Adds a tool tip to widget and to tool tip group group.
text is the text shown in the tool tip and longText is the text emitted from group. QToolTip makes deep copies of both strings.
Normally, longText is shown in a status bar or similar.
Adds a tool tip to a fixed rectangle, rect, within widget. text is the text shown in the tool tip. QToolTip makes a deep copy of this string.
Adds a tool tip to an entire widget and to tool tip group group.
text is the text shown in the tool tip and groupText is the text emitted from group. QToolTip makes deep copies of both strings.
Normally, groupText is shown in a status bar or similar.
See also setEnabled().
See also setFont().
Returns the tool tip group this QToolTip is a member of or 0 if it isn't a member of any group.
The tool tip group is the object responsible for maintaining contact between tool tips and a status bar or something else which can show the longer help text.
See also parentWidget() and QToolTipGroup.
Normally, there is no need to call this function; QToolTip takes care of showing and hiding the tips as the user moves the mouse.
This pure virtual function is half of the most versatile interface QToolTip offers.
It is called when there is a chance that a tool tip should be shown and must decide whether there is a tool tip for the point p in the widget that this QToolTip object relates to. If so, maybeTip() must call tip() with the rectangle the tip applies to, the tip's text and optionally the QToolTipGroup details.
p is given in that widget's local coordinates. Most maybeTip() implementations will be of the form:
if ( <something> ) { tip( <something>, <something> ); }
The first argument to tip() (a rectangle) should include the p, or QToolTip, the user or both can be confused.
Note that the tip will disappear once the mouse moves outside the rectangle you give to tip(), and will not reappear if the mouse moves back in - maybeTip() is called again instead.
See also tip().
Example: tooltip/tooltip.cpp.
See also setPalette().
Returns the widget this QToolTip applies to.
The tool tip is destroyed automatically when the parent widget is destroyed.
See also group().
If there is more than one tool tip on widget, only the one covering the entire widget is removed.
Removes the tool tip for rect from widget.
If there is more than one tool tip on widget, only the one covering rectangle rect is removed.
By default, tool tips are enabled. Note that this function affects all tool tips in the entire application.
See also QToolTipGroup::enabled.
See also font().
See also palette().
The tip will not reappear if the cursor moves back; your maybeTip() has to reinstate it each time.
Immediately pops up a tip saying text and removes that tip once the cursor moves out of rectangle rect. groupText is the text emitted from the group.
The tip will not reappear if the cursor moves back; your maybeTip() has to reinstate it each time.
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Copyright © 2001 Trolltech | Trademarks | Qt version 3.0.0-beta2
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