GtkSharp/sample/CustomScrollableWidget.cs
Bertrand Lorentz 2297695fd2 sample: Make the CustomScrollableWidget sample more elaborate
Make the custom widget a generic class, and add and use a derived class.
Also add a second instance of the custom widget, to better test the
interface properties support.
2011-12-03 16:41:21 +01:00

211 lines
4.7 KiB
C#

using GLib;
using Gtk;
using System;
class CustomScrollableWidgetTest {
public static int Main (string[] args)
{
Gtk.Application.Init ();
Window win = new Window ("Custom Scrollable Widget Test");
win.DeleteEvent += new DeleteEventHandler (OnQuit);
VPaned paned = new VPaned ();
ScrolledWindow scroll = new ScrolledWindow ();
scroll.HscrollbarPolicy = PolicyType.Automatic;
scroll.VscrollbarPolicy = PolicyType.Automatic;
var cw = new DerivedScrollableWidget<string> ("This one label that is repeated");
scroll.Add (cw);
paned.Pack1 (scroll, true, false);
scroll = new ScrolledWindow ();
scroll.HscrollbarPolicy = PolicyType.Automatic;
scroll.VscrollbarPolicy = PolicyType.Automatic;
var cw2 = new DerivedScrollableWidget<object> ("Another label that is repeated");
scroll.Add (cw2);
paned.Pack2 (scroll, true, false);
win.Add (paned);
win.DefaultWidth = 200;
win.DefaultHeight = 200;
win.ShowAll ();
Gtk.Application.Run ();
return 0;
}
static void OnQuit (object sender, DeleteEventArgs args)
{
Gtk.Application.Quit ();
}
}
abstract class CustomBase : Widget
{
public CustomBase () : base ()
{ }
}
class DerivedScrollableWidget<T> : CustomScrollableWidget<T>
{
public DerivedScrollableWidget (string label) : base (label)
{ }
}
class CustomScrollableWidget<T> : CustomBase, ScrollableImplementor {
private int num_rows = 20;
private string label;
private Pango.Layout layout;
public CustomScrollableWidget (string custom_label) : base ()
{
label = custom_label;
layout = null;
HasWindow = false;
}
private Pango.Layout Layout {
get {
if (layout == null)
layout = CreatePangoLayout (label);
return layout;
}
}
private Gdk.Rectangle ContentArea {
get {
Gdk.Rectangle area;
area.X = Allocation.X;
area.Y = Allocation.Y;
int layoutWidth, layoutHeight;
Layout.GetPixelSize (out layoutWidth, out layoutHeight);
area.Width = layoutWidth;
area.Height = layoutHeight * num_rows;
return area;
}
}
protected override bool OnDrawn (Cairo.Context cr)
{
int layout_x = - HadjustmentValue;
int layout_y = - VadjustmentValue;
int layoutWidth, layoutHeight;
Layout.GetPixelSize (out layoutWidth, out layoutHeight);
for (int i = 0; i < num_rows; i++) {
Layout.SetText (String.Format ("{0} {1}", label, i));
StyleContext.RenderLayout (cr, layout_x, layout_y, Layout);
layout_y += layoutHeight;
}
return base.OnDrawn (cr);
}
protected override void OnSizeAllocated (Gdk.Rectangle allocation)
{
base.OnSizeAllocated (allocation);
if (hadjustment != null) {
hadjustment.PageSize = allocation.Width;
hadjustment.PageIncrement = allocation.Width;
UpdateAdjustments ();
}
if (vadjustment != null) {
vadjustment.PageSize = allocation.Height;
vadjustment.PageIncrement = allocation.Height;
UpdateAdjustments ();
}
}
private Adjustment hadjustment;
public Adjustment Hadjustment {
get { return hadjustment; }
set {
if (value == hadjustment) {
return;
}
hadjustment = value;
if (hadjustment == null) {
return;
}
hadjustment.ValueChanged += OnHadjustmentChanged;
UpdateAdjustments ();
}
}
private Adjustment vadjustment;
public Adjustment Vadjustment {
get { return vadjustment; }
set {
if (value == vadjustment) {
return;
}
vadjustment = value;
if (vadjustment == null) {
return;
}
vadjustment.ValueChanged += OnVadjustmentChanged;
UpdateAdjustments ();
}
}
private int HadjustmentValue {
get { return hadjustment == null ? 0 : (int)hadjustment.Value; }
}
private int VadjustmentValue {
get { return vadjustment == null ? 0 : (int)vadjustment.Value; }
}
public Gtk.ScrollablePolicy HscrollPolicy {
get; set;
}
public Gtk.ScrollablePolicy VscrollPolicy {
get; set;
}
private void UpdateAdjustments ()
{
int layoutWidth, layoutHeight;
Layout.GetPixelSize (out layoutWidth, out layoutHeight);
if (hadjustment != null) {
hadjustment.Upper = ContentArea.Width;
hadjustment.StepIncrement = 10.0;
if (hadjustment.Value + hadjustment.PageSize > hadjustment.Upper) {
hadjustment.Value = hadjustment.Upper - hadjustment.PageSize;
}
hadjustment.Change ();
}
if (vadjustment != null) {
vadjustment.Upper = ContentArea.Height;
vadjustment.StepIncrement = layoutHeight;
if (vadjustment.Value + vadjustment.PageSize > vadjustment.Upper) {
vadjustment.Value = vadjustment.Upper - vadjustment.PageSize;
}
vadjustment.Change ();
}
}
private void OnHadjustmentChanged (object o, EventArgs args)
{
UpdateAdjustments ();
QueueDraw ();
}
private void OnVadjustmentChanged (object o, EventArgs args)
{
UpdateAdjustments ();
QueueDraw ();
}
}