Android : Android Draw a line with in 1 second

I have a class DrawView like this example with some modifications How to draw a line in android

I need to draw a line for example from position (0,0) to (10,0). That’s easy:

canvas.drawLine(0,0,10,0);

And here are my two problems:

1) I have my draw, but when I setContentView, all my layout that have buttons, textViews, etc. disappear and show my line. I want to put that draw in a view or something, how can I do that? Or draw it in the layout but not disappear the other views.

2) That line I draw I want to draw it with time, slowly. I want to draw de line for example in 1 second, is this possible? How is the best way to do it? I can’t find something related with this or a solution.

Greets