Adroid平台图表案例源码

Android平台创建xy图表的案例分析源码介绍，来看一下详细的源码

绘制网格线的方法

public static void  draw_the_grid(Canvas this_g,  Vector these_labels)

 

     {        

 

        double rounded_max = 0.0;

 

        double rounded_min = 0.0;

 

        double rounded_max_temp;

 

        Object curElt; 

 

        String[] cur_elt_array;

 

        int left_margin_d, right_margin_d;     

 

        if( draw_only_this_idx == -1)     

 

           curElt = these_labels.elementAt(0);  // default  it to 1st one if non set

 

        else

 

           curElt = these_labels.elementAt(draw_only_this_idx);  // now just the 1st elt

 

             

 

        cur_elt_array = (String[])curElt;

 

        rounded_max = get_ceiling_or_floor (Double.parseDouble(cur_elt_array[2]) , true);

 

        rounded_min = get_ceiling_or_floor (Double.parseDouble(cur_elt_array[3]) , false);

  

 

       // ok so now we have the max value of the set just get a cool ceiling and we go on

 

        final Paint paint = new Paint(); 

 

        paint.setTextSize(15);

 

       left_margin_d =  getCurTextLengthInPixels(paint, Double.toString(rounded_max));

 

       //keep the position for later drawing -- leave space for the legend

 

       int p_height = 170;

 

       int p_width = 220;

 

       int[] tmp_draw_sizes = {2 + left_margin_d, 25,p_width - 2 -

 

        left_margin_d ,p_height - 25 -5};

 

       drawSizes = tmp_draw_sizes; //keep it for later processing

 

        //with the mzrgins worked out draw the plotting grid

 

       paint.setStyle(Paint.Style.FILL);

 

       paint.setColor(Color.WHITE ); 

 

       // Android does by coords

 

       this_g.drawRect(drawSizes[0], drawSizes[1],drawSizes[0]+

 

        drawSizes[2], drawSizes[1]+ drawSizes[3] , paint);

 

         

 

       paint.setColor(Color.GRAY );      

 

       // finally draw the grid     

          

        paint.setStyle(Paint.Style.STROKE);

 

       this_g.drawRect(drawSizes[0], drawSizes[1],drawSizes[0]+

 

        drawSizes[2], drawSizes[1]+ drawSizes[3] , paint);

 

  

 

           for(int i=1; i < 5 ; i++)

 

           {

 

               this_g.drawLine(drawSizes[0], drawSizes[1] +

 

        (i * drawSizes[3] / 5), drawSizes[0] + drawSizes[2],

 

        drawSizes[1] + (i * drawSizes[3] / 5), paint);

 

               this_g.drawLine(drawSizes[0]+ (i * drawSizes[2] / 5),

 

        drawSizes[1], drawSizes[0] + (i * drawSizes[2] / 5),

 

        drawSizes[1] + drawSizes[3], paint);

 

           }

 

  

 

          // good for one value

 

           print_axis_values_4_grid(this_g, cur_elt_array[1] ,

 

        Double.toString(rounded_max) , Double.toString(rounded_min),

 

        cur_elt_array[0] , 2 ,0 );

 

           

 

     }  // --- end of draw_grid ---