ios - Chat Bubble in Swift3 -

i trying draw chat bubble , looks attached picture.

using beizer path mask draw shape , set mask textview. code follows ,

    let xposition = self.textview.frame.origin.x     let yposition = self.textview.frame.origin.y      //first direction - didnt work     /*let firstpoint = cgpoint(x: xposition, y: yposition)     let secondpoint = cgpoint(x: uiscreen.main.bounds.width - 5, y: firstpoint.y)     let thirdpoint = cgpoint(x: secondpoint.x - 15, y: secondpoint.y + 10)     let fourthpoint = cgpoint(x: thirdpoint.x, y: yposition + self.textview.frame.size.height)     let fifthpoint = cgpoint(x:firstpoint.x,y:fourthpoint.y)*/      //second direction - didnt work     /*let firstpoint = cgpoint(x:uiscreen.main.bounds.width - 5,y:yposition)     let secondpoint = cgpoint(x:xposition,y:yposition)     let thirdpoint = cgpoint(x: secondpoint.x, y: yposition + self.textview.frame.size.height)     let fourthpoint = cgpoint(x: firstpoint.x - 15, y: thirdpoint.y)     let fifthpoint = cgpoint(x: fourthpoint.x , y: firstpoint.y + 10)*/      let firstpoint = cgpoint(x: xposition, y: yposition)     let secondpoint = cgpoint(x:firstpoint.x,y:yposition + self.textview.frame.size.height)     let thirdpoint = cgpoint(x: xposition + self.textview.frame.width - 20, y: secondpoint.y)     let fourthpoint = cgpoint(x: thirdpoint.x, y: yposition + 15)     let fifthpoint = cgpoint(x: xposition + self.textview.frame.width , y: yposition)      let maskpath =  uibezierpath()     maskpath.move(to: firstpoint)     maskpath.addline(to: secondpoint)     maskpath.addline(to: thirdpoint)     maskpath.addline(to: fourthpoint)     maskpath.addline(to: fifthpoint)     maskpath.addline(to: firstpoint)     maskpath.close()      let masklayer = cashapelayer()     masklayer.path = maskpath.cgpath     textview.layer.mask = masklayer 

i tried draw lines different directions , still rectangular shape , no chat pointer shown in picture. suggestions on achieving chat bubble ?