Android: Draw a view on canvas

问题

I have a view inflated, I can draw it on canvas, but can't seem to position it properly.

LayoutInflater li = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View v = li.inflate(R.layout.fix_this_recommendation, null);
v.measure(MeasureSpec.getSize(v.getMeasuredWidth()), MeasureSpec.getSize(v.getMeasuredHeight()));
v.layout(400, 400, 400, 400);
v.draw(canvas);

But the view is always at the top left corner. Anyone know why?

回答1:

Each View draws its contents within its own coordinate system, with (0, 0) at the top-left. If you want it to appear elsewhere, you can set a new transformation matrix on your Canvas.

回答2:

Solution is to translate canvas:

canvas.save();
canvas.translate(left, top);            
view.draw(canvas);
canvas.restore();

回答3:

because the coordinate system used in the Canvas starts from the top left corner instead of doing that define your Custom View and override the onDraw() method and inside it position your view as you like

回答4:

use drawChild(canvas,child,getDrawingTime()); instead of child.draw(canvas)

drawChild will calc child's top and left margin

来源：https://stackoverflow.com/questions/9204542/android-draw-a-view-on-canvas