/// <summary>
/// Scrolls the specified widget to the specified coordinates, except
/// constrains the X scrolling position to the horizontal regions of
/// the text that will be visible after scrolling to the specified
/// Y position.
/// </summary>
/// <remarks>
/// Scrolls the specified widget to the specified coordinates, except
/// constrains the X scrolling position to the horizontal regions of
/// the text that will be visible after scrolling to the specified
/// Y position.
/// </remarks>
public static void scrollTo(android.widget.TextView widget, android.text.Layout layout
, int x, int y)
{
int verticalPadding = widget.getTotalPaddingTop() + widget.getTotalPaddingBottom(
);
int top = layout.getLineForVertical(y);
int bottom = layout.getLineForVertical(y + widget.getHeight() - verticalPadding);
int left = int.MaxValue;
int right = 0;
android.text.Layout.Alignment?a = layout.getParagraphAlignment(top);
bool ltr = layout.getParagraphDirection(top) > 0;
{
for (int i = top; i <= bottom; i++)
{
left = (int)System.Math.Min(left, layout.getLineLeft(i));
right = (int)System.Math.Max(right, layout.getLineRight(i));
}
}
int hoizontalPadding = widget.getTotalPaddingLeft() + widget.getTotalPaddingRight
();
int availableWidth = widget.getWidth() - hoizontalPadding;
int actualWidth = right - left;
if (actualWidth < availableWidth)
{
if (a == android.text.Layout.Alignment.ALIGN_CENTER)
{
x = left - ((availableWidth - actualWidth) / 2);
}
else
{
if ((ltr && (a == android.text.Layout.Alignment.ALIGN_OPPOSITE)) || (a == android.text.Layout.Alignment
.ALIGN_RIGHT))
{
// align_opposite does NOT mean align_right, we need the paragraph
// direction to resolve it to left or right
x = left - (availableWidth - actualWidth);
}
else
{
x = left;
}
}
}
else
{
x = System.Math.Min(x, right - availableWidth);
x = System.Math.Max(x, left);
}
widget.scrollTo(x, y);
}
private int getScrollBoundsRight(android.widget.TextView widget)
{
android.text.Layout layout = widget.getLayout();
int topLine = getTopLine(widget);
int bottomLine = getBottomLine(widget);
if (topLine > bottomLine)
{
return 0;
}
int right_1 = int.MinValue;
{
for (int line = topLine; line <= bottomLine; line++)
{
int lineRight = (int)System.Math.Ceiling(layout.getLineRight(line));
if (lineRight > right_1)
{
right_1 = lineRight;
}
}
}
return right_1;
}