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Diffstat (limited to 'src/gui/tipViewer.vala')
| -rw-r--r-- | src/gui/tipViewer.vala | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/src/gui/tipViewer.vala b/src/gui/tipViewer.vala new file mode 100644 index 0000000..c653dd9 --- /dev/null +++ b/src/gui/tipViewer.vala @@ -0,0 +1,172 @@ +/* +Copyright (c) 2011 by Simon Schneegans + +This program is free software: you can redistribute it and/or modify it +under the terms of the GNU General Public License as published by the Free +Software Foundation, either version 3 of the License, or (at your option) +any later version. + +This program 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 General Public License for +more details. + +You should have received a copy of the GNU General Public License along with +this program. If not, see <http://www.gnu.org/licenses/>. +*/ + +namespace GnomePie { + +///////////////////////////////////////////////////////////////////////// +/// A widget showing tips. The tips are beautifully faded in and out. +///////////////////////////////////////////////////////////////////////// + +public class TipViewer : Gtk.Label { + + ///////////////////////////////////////////////////////////////////// + /// Some settings tweaking the behavior of the TipViewer. + ///////////////////////////////////////////////////////////////////// + + private const double fade_time = 0.5; + private const double frame_rate = 20.0; + private const double delay = 7.0; + + ///////////////////////////////////////////////////////////////////// + /// False, if the playback of tips is stopped. + ///////////////////////////////////////////////////////////////////// + + private bool playing = false; + + ///////////////////////////////////////////////////////////////////// + /// An array containing all tips. + ///////////////////////////////////////////////////////////////////// + + private string[] tips; + + ///////////////////////////////////////////////////////////////////// + /// The index of the currently displayed tip. + ///////////////////////////////////////////////////////////////////// + + private int index = -1; + + ///////////////////////////////////////////////////////////////////// + /// Colors of the font and the background. Used for fading effects. + ///////////////////////////////////////////////////////////////////// + + private Gdk.Color fg; + private Gdk.Color bg; + + ///////////////////////////////////////////////////////////////////// + /// The fading value. + ///////////////////////////////////////////////////////////////////// + + private AnimatedValue alpha; + + ///////////////////////////////////////////////////////////////////// + /// C'tor, initializes all members and sets the basic layout. + ///////////////////////////////////////////////////////////////////// + + public TipViewer(string[] tips) { + this.tips = tips; + this.fg = this.get_style().fg[0]; + this.bg = this.get_style().bg[0]; + + this.alpha = new AnimatedValue.linear(1.0, 0.0, this.fade_time); + + this.set_alignment (0.0f, 0.5f); + this.wrap = true; + this.set_use_markup(true); + this.modify_font(Pango.FontDescription.from_string("9")); + + this.set_random_tip(); + } + + ///////////////////////////////////////////////////////////////////// + /// Starts the playback of tips. + ///////////////////////////////////////////////////////////////////// + + public void start_slide_show() { + if (!this.playing && tips.length > 1) { + this.playing = true; + GLib.Timeout.add((uint)(this.delay*1000.0), () => { + this.fade_out(); + + GLib.Timeout.add((uint)(1000.0*this.fade_time), () => { + this.set_random_tip(); + this.fade_in(); + return false; + }); + + return this.playing; + }); + } + } + + ///////////////////////////////////////////////////////////////////// + /// Stops the playback of tips. + ///////////////////////////////////////////////////////////////////// + + public void stop_slide_show() { + this.playing = false; + } + + ///////////////////////////////////////////////////////////////////// + /// Starts the fading in. + ///////////////////////////////////////////////////////////////////// + + private void fade_in() { + this.alpha = new AnimatedValue.linear(this.alpha.val, 1.0, this.fade_time); + + GLib.Timeout.add((uint)(1000.0/this.frame_rate), () => { + this.alpha.update(1.0/this.frame_rate); + this.update_label(); + + return (this.alpha.val != 1.0); + }); + } + + ///////////////////////////////////////////////////////////////////// + /// Starts the fading out. + ///////////////////////////////////////////////////////////////////// + + private void fade_out() { + this.alpha = new AnimatedValue.linear(this.alpha.val, 0.0, this.fade_time); + + GLib.Timeout.add((uint)(1000.0/this.frame_rate), () => { + this.alpha.update(1.0/this.frame_rate); + this.update_label(); + + return (this.alpha.val != 0.0); + }); + } + + ///////////////////////////////////////////////////////////////////// + /// Updates the color of the label. Called every frame while fading. + ///////////////////////////////////////////////////////////////////// + + private void update_label() { + Gdk.Color color = {(uint32)(fg.pixel*this.alpha.val + bg.pixel*(1.0 - this.alpha.val)), + (uint16)(fg.red*this.alpha.val + bg.red*(1.0 - this.alpha.val)), + (uint16)(fg.green*this.alpha.val + bg.green*(1.0 - this.alpha.val)), + (uint16)(fg.blue*this.alpha.val + bg.blue*(1.0 - this.alpha.val))}; + + this.modify_fg(Gtk.StateType.NORMAL, color); + } + + ///////////////////////////////////////////////////////////////////// + /// Chooses the next random tip. + ///////////////////////////////////////////////////////////////////// + + private void set_random_tip() { + if (tips.length > 1) { + int next_index = -1; + do { + next_index = GLib.Random.int_range(0, tips.length); + } while (next_index == this.index); + this.index = next_index; + this.label = tips[this.index]; + } + } +} + +} |