How to use android canvas to draw a Rectangle with only topleft and topright corners round?

Question

I found a function for rectangles with all 4 corners being round, but I want to have just the top 2 corners round. What can I do?

canvas.drawRoundRect(new Re         


        

Answer 1

This is an old question, however I wanted to add my solution because it uses the native SDK without lots of custom code or hacky drawing. This solution is supported back to API 1.

The way to do this properly is to create a path (as mentioned in other answers) however the previous answers seem to overlook the addRoundedRect function call that takes radii for each corner.

Variables

private val path = Path()
private val paint = Paint()

Setup Paint

paint.color = Color.RED
paint.style = Paint.Style.FILL

Update Path with Size Changes

Call this somewhere that isn't onDraw, such as onMeasure for a view or onBoundChange for a drawable. If it doesn't change (like this example) you could put this code where you set up your paint.

val radii = floatArrayOf(
    25f, 25f, //Top left corner
    25f, 25f, //Top right corner
    0f, 0f,   //Bottom right corner
    0f, 0f,   //Bottom left corner
)

path.reset() //Clears the previously set path
path.addRoundedRect(0f, 0f, 100f, 100f, radii, Path.Direction.CW)

This code creates a 100x100 rounded rect with the top corners rounded with a 25 radius.

Draw Path

Call this in onDraw for a view or draw for a drawable.

canvas.drawPath(path, paint)