Draw bar chart in android

This is the same as the Last Tutorial i have posted. We just need to implement the following code in the View instead of the last tutorial.


public class DrawBarChart extends View {
Paint paint = new Paint();
int c[] = { Color.BLUE, Color.RED };
Canvas mCanvas = new Canvas();
private float[] val_exp;
private float[] val_inco;
Context context;
WindowManager mWinMgr;

public DrawBarChart(Context context) {
super(context);
paint = new Paint();
super.draw(mCanvas);
}

public DrawBarChart(Context context, AttributeSet attrs) {
super(context, attrs);
paint = new Paint();
super.draw(mCanvas);
}

public DrawBarChart(Context context, float[] val_exp, float[] val_inco) {
super(context);
paint = new Paint();
this.val_exp = val_exp;
this.val_inco = val_inco;
super.draw(mCanvas);
}

public void draw(Canvas canvas) {
int x = getWidth();
int y = getHeight();
float max = getMax();
paint.setColor(Color.parseColor("#78777D"));
paint.setStyle(Style.STROKE);
paint.setStrokeWidth(2);
canvas.drawRect(0, 0, x - 1, y - 1, paint);
int n = val_exp.length;
int gap = x / 12;
paint.setStyle(Style.FILL);
for (int i = 0; i < n; i++) {

paint.setColor(Color.BLACK);
//Bottom Numbers 1 to 12.
canvas.drawText("" + (i + 1), i * gap + (gap / 2), y - 5, paint);    

//Vertical Lines.
canvas.drawLine((float) (i + 0.5) * gap + 4, y - 15,
(float) (i + 0.5) * gap + 4, y - 25, paint);    
            
// Blue bars for Income.
paint.setColor(Color.BLUE);
canvas.drawLine(i * gap + 5, y - 20, (float) (i + 0.5) * gap + 3,
y - 20, paint);

float bHeIn =(max==0)?y-20:  y - (val_inco[i] * (y - 22) / max)- 20;

canvas.drawRect((float) i   * gap + 5, bHeIn,
(float) (i + 0.5) * gap + 3, y - 20, paint);

// Red bars for Expenses.
paint.setColor(Color.RED);
canvas.drawLine((float) (i + 0.5) * gap + 5, y - 20,
(float) (i + 1) * gap + 3, y - 20, paint);

float bHeEx =(max==0)?y-20:  y - (val_exp[i] * (y - 22) / max)- 20;

canvas.drawRect((float) (i + 0.5) * gap + 5, bHeEx,
(float) (i + 1) * gap + 3, y - 20, paint);
}
}

private float getMax() {
float max = 0;
for (float f : val_exp) {
if (f > max)
max = f;
}
for (float f : val_inco) {
if (f > max)
max = f;
}
return max;
}
}

And for drawing the chart of the values of the data you need to pass the values to the objects of the class as follow.    


           DrawBarChart barView;
           LinearLayout la;

           barView = new DrawBarChart(this, vals_exp,vals_inco);
          la.addView(barView);