Borrowed the KMessageWidget code to better show passive information.

Borrowed the code from KMessageWidget from Aurelian Gateau, Kdelibs,
to better show passive information and notifications. instead of a
popup blowing in the user's face, a nice, animated and well designed
widget will gracefully fade-in, show the notes, and fade out when
not needed anymore.

Signed-off-by: Tomaz Canabrava <tcanabrava@kde.org>

qt-ui/kmessagewidget.h

@@ -0,0 +1,241 @@
+/* This file is part of the KDE libraries
+ *
+ * Copyright (c) 2011 Aurélien Gâteau <agateau@kde.org>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301  USA
+ */
+#ifndef KMESSAGEWIDGET_H
+#define KMESSAGEWIDGET_H
+
+#include <kdeui_export.h>
+
+#include <QFrame>
+
+class KMessageWidgetPrivate;
+
+/**
+ * @short A widget to provide feedback or propose opportunistic interactions.
+ *
+ * KMessageWidget can be used to provide inline positive or negative
+ * feedback, or to implement opportunistic interactions.
+ *
+ * As a feedback widget, KMessageWidget provides a less intrusive alternative
+ * to "OK Only" message boxes. If you do not need the modalness of KMessageBox,
+ * consider using KMessageWidget instead.
+ *
+ * <b>Negative feedback</b>
+ *
+ * The KMessageWidget can be used as a secondary indicator of failure: the
+ * first indicator is usually the fact the action the user expected to happen
+ * did not happen.
+ *
+ * Example: User fills a form, clicks "Submit".
+ *
+ * @li Expected feedback: form closes
+ * @li First indicator of failure: form stays there
+ * @li Second indicator of failure: a KMessageWidget appears on top of the
+ * form, explaining the error condition
+ *
+ * When used to provide negative feedback, KMessageWidget should be placed
+ * close to its context. In the case of a form, it should appear on top of the
+ * form entries.
+ *
+ * KMessageWidget should get inserted in the existing layout. Space should not
+ * be reserved for it, otherwise it becomes "dead space", ignored by the user.
+ * KMessageWidget should also not appear as an overlay to prevent blocking
+ * access to elements the user needs to interact with to fix the failure.
+ *
+ * <b>Positive feedback</b>
+ *
+ * KMessageWidget can be used for positive feedback but it shouldn't be
+ * overused. It is often enough to provide feedback by simply showing the
+ * results of an action.
+ *
+ * Examples of acceptable uses:
+ *
+ * @li Confirm success of "critical" transactions
+ * @li Indicate completion of background tasks
+ *
+ * Example of inadapted uses:
+ *
+ * @li Indicate successful saving of a file
+ * @li Indicate a file has been successfully removed
+ *
+ * <b>Opportunistic interaction</b>
+ *
+ * Opportunistic interaction is the situation where the application suggests to
+ * the user an action he could be interested in perform, either based on an
+ * action the user just triggered or an event which the application noticed.
+ *
+ * Example of acceptable uses:
+ *
+ * @li A browser can propose remembering a recently entered password
+ * @li A music collection can propose ripping a CD which just got inserted
+ * @li A chat application may notify the user a "special friend" just connected
+ *
+ * @author Aurélien Gâteau <agateau@kde.org>
+ * @since 4.7
+ */
+class KMessageWidget : public QFrame
+{
+    Q_OBJECT
+    Q_ENUMS(MessageType)
+
+    Q_PROPERTY(QString text READ text WRITE setText)
+    Q_PROPERTY(bool wordWrap READ wordWrap WRITE setWordWrap)
+    Q_PROPERTY(bool closeButtonVisible READ isCloseButtonVisible WRITE setCloseButtonVisible)
+    Q_PROPERTY(MessageType messageType READ messageType WRITE setMessageType)
+    Q_PROPERTY(QIcon icon READ icon WRITE setIcon)
+public:
+    enum MessageType {
+        Positive,
+        Information,
+        Warning,
+        Error
+    };
+
+    /**
+     * Constructs a KMessageWidget with the specified parent.
+     */
+    explicit KMessageWidget(QWidget *parent = 0);
+
+    explicit KMessageWidget(const QString &text, QWidget *parent = 0);
+
+    ~KMessageWidget();
+
+    QString text() const;
+
+    bool wordWrap() const;
+
+    bool isCloseButtonVisible() const;
+
+    MessageType messageType() const;
+
+    void addAction(QAction *action);
+
+    void removeAction(QAction *action);
+
+    QSize sizeHint() const;
+
+    QSize minimumSizeHint() const;
+
+    int heightForWidth(int width) const;
+
+    /**
+     * The icon shown on the left of the text. By default, no icon is shown.
+     * @since 4.11
+     */
+    QIcon icon() const;
+
+public Q_SLOTS:
+    void setText(const QString &text);
+
+    void setWordWrap(bool wordWrap);
+
+    void setCloseButtonVisible(bool visible);
+
+    void setMessageType(KMessageWidget::MessageType type);
+
+    /**
+     * Show the widget using an animation, unless
+     * KGlobalSettings::graphicsEffectLevel() does not allow simple effects.
+     */
+    void animatedShow();
+
+    /**
+     * Hide the widget using an animation, unless
+     * KGlobalSettings::graphicsEffectLevel() does not allow simple effects.
+     */
+    void animatedHide();
+
+    /**
+     * Define an icon to be shown on the left of the text
+     * @since 4.11
+     */
+    void setIcon(const QIcon &icon);
+
+Q_SIGNALS:
+    /**
+     * This signal is emitted when the user clicks a link in the text label.
+     * The URL referred to by the href anchor is passed in contents.
+     * @param contents text of the href anchor
+     * @see QLabel::linkActivated()
+     * @since 4.10
+     */
+    void linkActivated(const QString& contents);
+
+    /**
+     * This signal is emitted when the user hovers over a link in the text label.
+     * The URL referred to by the href anchor is passed in contents.
+     * @param contents text of the href anchor
+     * @see QLabel::linkHovered()
+     * @since 4.11
+     */
+    void linkHovered(const QString& contents);
+
+protected:
+    void paintEvent(QPaintEvent *event);
+
+    bool event(QEvent *event);
+
+    void resizeEvent(QResizeEvent *event);
+
+    void showEvent(QShowEvent *event);
+
+private:
+    KMessageWidgetPrivate *const d;
+    friend class KMessageWidgetPrivate;
+
+    Q_PRIVATE_SLOT(d, void slotTimeLineChanged(qreal))
+    Q_PRIVATE_SLOT(d, void slotTimeLineFinished())
+};
+
+//---------------------------------------------------------------------
+// KMessageWidgetPrivate
+//---------------------------------------------------------------------
+class QLabel;
+class QToolButton;
+class QTimeLine;
+#include <QIcon>
+
+class KMessageWidgetPrivate
+{
+public:
+	void init(KMessageWidget*);
+
+	KMessageWidget* q;
+	QFrame* content;
+	QLabel* iconLabel;
+	QLabel* textLabel;
+	QToolButton* closeButton;
+	QTimeLine* timeLine;
+	QIcon icon;
+
+	KMessageWidget::MessageType messageType;
+	bool wordWrap;
+	QList<QToolButton*> buttons;
+	QPixmap contentSnapShot;
+
+	void createLayout();
+	void updateSnapShot();
+	void updateLayout();
+	void slotTimeLineChanged(qreal);
+	void slotTimeLineFinished();
+
+	int bestContentHeight() const;
+};
+
+#endif /* KMESSAGEWIDGET_H */