public void SetHeight(object backend, double value)
{
LayoutBackend la = (LayoutBackend)backend;
la.Heigth = value;
la.Measured = false;
}
public void SetText(object backend, string text)
{
LayoutBackend la = (LayoutBackend)backend;
la.Text = text;
la.Measured = false;
}
public void SetFont(object backend, Font font)
{
LayoutBackend la = (LayoutBackend)backend;
la.Measured = false;
la.Font = font;
}
public void SetWidth(object backend, double value)
{
LayoutBackend la = (LayoutBackend)backend;
la.Width = value;
la.Measured = false;
}
public object Create(Context context)
{
CairoContextBackend c = (CairoContextBackend)WidgetRegistry.GetBackend(context);
LayoutBackend b = new LayoutBackend();
b.Context = c;
return(b);
}
public object Create(ICanvasBackend canvas)
{
LayoutBackend b = new LayoutBackend();
CairoContextBackend ba = new CairoContextBackend();
ba.Context = SharedContext;
b.Context = ba;
return(b);
}
static Size Measure(object backend)
{
LayoutBackend la = (LayoutBackend)backend;
var ctx = la.Context.Context;
var text = la.Text;
if (la.Font != null)
{
ctx.SelectFont(la.Font);
ctx.SetFontSize(la.Font.Size);
}
if (la.Width == -1)
{
var te = ctx.TextExtents(text);
return(new Size(te.Width, te.Height));
}
// Measure word by word
double totalHeight = 0;
double currentWidth = 0;
double currentHeight = 0;
la.LineBreaks.Clear();
double spaceWidth = ctx.TextExtents(" ").XAdvance;
double spaceHeight = ctx.FontExtents.Height;
var spaceExtents = new Cairo.TextExtents()
{
Width = spaceWidth,
Height = spaceHeight,
XAdvance = spaceWidth
};
int pos = 0;
bool inLineStart = true;
int prevPos = 0;
string word = NextWord(text, ref pos);
for (; word != null; prevPos = pos, word = NextWord(text, ref pos))
{
if (word.Length == 1 && word [0] == '\n')
{
if (inLineStart)
{
// Empty line
currentHeight = spaceHeight;
}
totalHeight += currentHeight;
la.LineBreaks.Add(pos);
la.LineHeights.Add(currentHeight);
currentHeight = 0;
currentWidth = 0;
inLineStart = true;
continue;
}
inLineStart = false;
bool isSpace = word.Length == 1 && word[0] == ' ';
Cairo.TextExtents te;
if (isSpace)
{
te = spaceExtents;
}
else
{
te = ctx.TextExtents(word);
}
if (currentWidth + te.Width > la.Width)
{
la.LineHeights.Add(currentHeight);
la.LineBreaks.Add(isSpace ? pos : prevPos); // If a space causes a line break, we can ignore that space
totalHeight += currentHeight;
currentHeight = te.Height;
if (isSpace)
{
currentWidth = 0;
}
else
{
currentWidth = te.Width;
}
}
else
{
currentWidth += te.XAdvance;
if (te.Height > currentHeight)
{
currentHeight = te.Height;
}
}
}
la.Measured = true;
return(new Size(la.Width, totalHeight));
}
public void SetTrimming(object backend, TextTrimming textTrimming)
{
LayoutBackend la = (LayoutBackend)backend;
la.TextTrimming = textTrimming;
}
public override object Create(ICanvasBackend canvas)
{
LayoutBackend b = new LayoutBackend ();
CairoContextBackend ba = new CairoContextBackend ();
ba.Context = SharedContext;
b.Context = ba;
return b;
}
public override object Create(Context context)
{
CairoContextBackend c = (CairoContextBackend) Toolkit.GetBackend (context);
LayoutBackend b = new LayoutBackend ();
b.Context = c;
return b;
}
public object Create(Context context)
{
CairoContextBackend c = (CairoContextBackend) WidgetRegistry.GetBackend (context);
LayoutBackend b = new LayoutBackend ();
b.Context = c;
return b;
}
