//  TurningArrowView.java  Copyright (c) Kari Laitinen

//  http://www.naturalprogramming.com/

//  2016-03-04  File created.
//  2016-03-04  Last modification.


/*  The custom View for the TurningArrow app.

*/


package turning.arrow ;

import android.app.Activity ;
import android.os.Bundle ;
import android.graphics.* ;  // Classes Canvas, Color, Paint, RectF, etc.
import android.view.View ;
import android.content.Context ;
import android.util.AttributeSet ;

final class TurningArrowView extends View
{
   int view_center_point_x = 0 ;
   int view_center_point_y = 0 ;
   int arrow_angle = 0 ;

   Paint filling_paint = new Paint() ;
   Paint outline_paint = new Paint() ;

   Path  upwards_arrow  =  new  Path() ;

   //  The following constructor is needed when TurningArrowView object is
   //  specified in an XML file, and is thus created automatically.

   public TurningArrowView( Context context, AttributeSet attributes ) 
   {
      super( context, attributes ) ;

      filling_paint.setStyle( Paint.Style.FILL ) ;
      filling_paint.setColor( Color.MAGENTA ) ;

      outline_paint.setStyle( Paint.Style.STROKE ) ;
      outline_paint.setColor( Color.RED ) ;
      outline_paint.setStrokeWidth( 2 ) ;

      // The background color of this view is set in the XML file
      //setBackgroundColor( 0xFFFFFFE0 ) ; // Light Yellow

      //  The arrow coordinates are selected so that Point (0, 0)
      //  is in the middle of the arrow, and the arrow points upwards.

      upwards_arrow.moveTo( 0, -192 ) ;   // to the tip of the arrow
      upwards_arrow.lineTo( 128,   0 ) ;
      upwards_arrow.lineTo(  64,   0 ) ;
      upwards_arrow.lineTo(  64, 192 ) ;
      upwards_arrow.lineTo( -64, 192 ) ;  // make the bottom line
      upwards_arrow.lineTo( -64,   0 ) ;
      upwards_arrow.lineTo( -128,  0 ) ;
      upwards_arrow.close() ;
   }

   public void onSizeChanged( int current_width_of_this_view,
                              int current_height_of_this_view,
                              int old_width_of_this_view,
                              int old_height_of_this_view )
   {
      view_center_point_x = current_width_of_this_view / 2 ;
      view_center_point_y = current_height_of_this_view / 2 ;
   }

   public void set_arrow_angle( int new_arrow_angle )
   {
      arrow_angle = new_arrow_angle ;

      invalidate() ;
   }

   public void set_outline_stroke_width( int new_stroke_width )
   {
      outline_paint.setStrokeWidth( new_stroke_width ) ;

      invalidate() ;
   }

   protected void onDraw( Canvas canvas ) 
   {
      canvas.translate( view_center_point_x, view_center_point_y ) ;
      canvas.rotate( arrow_angle ) ; 
      canvas.drawPath( upwards_arrow, filling_paint ) ; // draw solid arrow
      canvas.drawPath( upwards_arrow, outline_paint ) ; // draw arrow outline
   }
}