PieChart 饼图

图表网上有很多第三方工具,但是往往都会受到一些限制,于是用canvas画pieChart.

 

 

Java代码

         // 定义一些常量
    int areaX = 1;
    int areaY = 22;
    int areaWidth;
    int areaHight;
     //pie上的颜色
    int colors[];
    //占的比例
    int percent[];
    int tempAngle = 0;
    private Bitmap bitmap;
    /**
     * 屏幕中间点的X、Y坐标
     */
    private float centerX,centerY;

    /**
     * 大园半径
     */
    private float bigR;
    private Canvas canvas;
    Bitmap OverlayBitmap;
    /**
     * 屏幕的宽
     */
    private int width;

    /**
     * 屏幕的高
     */
    private int height;

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        this.canvas = canvas;
        centerX = width / 2;
        centerY = height / 2;
        bigR = (width - 80) / 2;
        areaWidth = width - 2;
        areaHight = height - 2;
        Paint paint = new Paint();
        paint.setColor(Color.RED);
        paint.setStyle(Style.FILL);
        paint.setAntiAlias(true);
        paint.setStrokeWidth(1);

        canvas.save();
        canvas.rotate(mDegree);
        canvas.translate(centerX, centerY);
        for (int j = 0; j < percent.length; j++) {
             paint.setColor(colors[j]);
             canvas.drawArc(new RectF(-bigR, -bigR,bigR, bigR), tempAngle,percent[j],
                      true,paint);tempAngle += percent[j];
        }
        canvas.restore();
}

 把在饼图上占的各个部分,由在初始化此view时传参,代码便灵活使用

 

Java代码

int[] colors =new int[]{Color.rgb(255, 0, 68),Color.rgb(4, 227, 66),Color.rgb(120, 120, 120),Color.rgb(255, 145, 0)};
       int[] percent = new int[]{50,140,100,70};
       PieView pieView = new PieView(this,width,height,colors,percent);

percent 在饼图上所占的比例,无论里面有几个元素,总和都必须是360,不然画出来是有空缺的.

 

Java代码

    int mDegree = 0; // 偏移量
    int mPreDegree = 0; // 上次偏移量
    public void calcDegree(boolean bFlag) {
        if (mDegree >= 360) {
            mDegree -= 360;
        }

        if (mDegree < 0) {
            mDegree += 360;
        }

        mPreDegree = mDegree;
    }


@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    // TODO Auto-generated method stub

    switch (keyCode) {
//顺时针转动
    case KeyEvent.KEYCODE_DPAD_LEFT:
        mDegree -= 6;
        calcDegree(false);

        postInvalidate();
        break;
//逆时针转动
    case KeyEvent.KEYCODE_DPAD_RIGHT:
        mDegree += 6;
        calcDegree(false);

        postInvalidate();
        break;
    default:
        break;
    }

    return super.onKeyDown(keyCode, event);
}