canvas画柱状图 和饼图

Screenshot_1499828054.png

学习扔物线大大的教程 http://hencoder.com/ui-1-1/
https://github.com/hencoder/PracticeDraw1

饼图的指示文字还需要重新计算一下还有防止小扇区文字可能重叠的情况

    String[] strings = {"Froyo", "GB", "ICS", "JB", "Kitkat", "L", "M"};

{
//初始化画笔等
//...
        paintW.setColor(Color.WHITE);
        paintW.setStyle(Paint.Style.FILL);
        paintW.setTextSize(30);
        paintW.setTextAlign(Paint.Align.CENTER);

        paintG.setColor(Color.parseColor("#72B916"));
}

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);

//        drawGrid(canvas);

        Point point = new Point(150, 650);

        canvas.drawLine(point.x, 100, point.x, point.y, paintW);
        canvas.drawLine(point.x, point.y, 1050, point.y, paintW);

        int gapWidth = 20;
        int girdWidth = 80;

        for (int i = 0; i < 7; i++) {
            int gridHeight = (i + 1) * 80;

            int left = point.x + i * 100 + gapWidth;
            int top = point.y - gridHeight;
            int right = left + girdWidth;
            int bottom = point.y;

            canvas.drawRect(left, top, right, bottom, paintG);
        }

        for (int i = 0; i < 7; i++) {
            int x = point.x + gapWidth * (i + 1) + (girdWidth) * i + girdWidth / 2;
            int y = point.y + 30;
            canvas.drawText(strings[i], x, y, paintW);
        }

    }

Paste_Image.png

public class Practice11PieChartView extends View {
    private static final String TAG = "Practice11PieChartView";

    Paint paintArc = new Paint();//扇形画笔
    Paint mPaint = new Paint();//指示线画笔
    Paint textPaint = new Paint();//文字画笔
    RectF rectF = new RectF();

    int textSize = 30;
    int height = 0;

    Point centerPoint = new Point();//圆心
    float r;//半径


    public Practice11PieChartView(Context context, @Nullable AttributeSet attrs) {
        super(context, attrs);
    }


    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        height = getHeight() - 300;

        int left = 200;
        int top = 50;
        int right = left + height;
        int bottom = top + height;

        rectF = new RectF(left, top, right, bottom);
        results.add(new Result(180, 120, "#F44336", "Lollipop").setNeedMove(true));
        results.add(new Result(300, 60, "#FFC107", "Marshmallow"));
        results.add(new Result(3, 7, "#9C27B0", "Gingerbread"));
        results.add(new Result(13, 20, "#9E9E9E", "Ice Cream Sandwich"));
        results.add(new Result(36, 40, "#009688", "Jelly Bean"));
        results.add(new Result(80, 98, "#2196F3", "KitKat"));
        centerPoint.x = (right - left) / 2 + left;
        centerPoint.y = (bottom - top) / 2 + top;
        r = (right - left) / 2;

        mPaint.setColor(Color.WHITE);
        mPaint.setStrokeWidth(1);
        mPaint.setStyle(Paint.Style.STROKE);

        textPaint.setColor(Color.WHITE);
        textPaint.setTextSize(textSize);
    }


    ArrayList results = new ArrayList<>();

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
        for (Result result : results) {
            //画扇形
            drawArc(canvas, result);

            //画指示线
            drawPath(canvas, result);

            //是否需要离开圆心一些距离
            drawGap(canvas, result);
        }
    }

    private void drawGap(Canvas canvas, Result result) {
        if (result.needMove) {
            canvas.translate(10, 20);
        }
    }

    private void drawPath(Canvas canvas, Result result) {
        int x = (int) (centerPoint.x + r * Math.cos(result.getHalfAngle() * Math.PI / 180));
        int y = (int) (centerPoint.y + r * Math.sin(result.getHalfAngle() * Math.PI / 180));
        //判断指示线方向

        int[] type = getDirectionArray(x, y);

        Path path = new Path();
        path.moveTo(x, y);
        path.rLineTo(type[2], type[3]);
        path.rLineTo(type[4], type[5]);
        switch (type[0]) {
            case LEFT_TOP:
            case LEFT_BOTTOM:
                textPaint.setTextAlign(Paint.Align.RIGHT);
                break;
            case RIGHT_TOP:
            case RIGHT_BOTTOM:
                textPaint.setTextAlign(Paint.Align.LEFT);
                break;
        }
        canvas.drawPath(path, mPaint);

        int textX = type[2] + type[4] + x + type[1];

        int textY = type[3] + type[5] + y + textSize / 3;

        canvas.drawText(result.name, textX, textY, textPaint);

    }

    private int[] getDirectionArray(int x, int y) {
        int[] arr = new int[6];
        if (x < centerPoint.x) {
            arr[1] = arr[2] = -20;
            arr[4] = -100;
            arr[5] = 0;
            if (y < centerPoint.y) {//左上
                arr[0] = LEFT_TOP;
                arr[3] = -20;
            } else {//左下
                arr[0] = LEFT_BOTTOM;
                arr[3] = 20;
            }
        } else {
            arr[1] = arr[2] = 20;
            arr[4] = 100;
            arr[5] = 0;
            if (y < centerPoint.y) {//右上
                arr[0] = RIGHT_TOP;
                arr[3] = -20;
            } else {//右下
                arr[0] = RIGHT_BOTTOM;
                arr[3] = 20;
            }
        }
        return arr;
    }

    // TODO: 2017/7/13  防止重叠

    final int LEFT_TOP = 0;
    final int LEFT_BOTTOM = 1;
    final int RIGHT_TOP = 2;
    final int RIGHT_BOTTOM = 3;


    private void drawArc(Canvas canvas, Result result) {
        paintArc.setColor(result.color);
        canvas.drawArc(rectF, result.startAngle, result.sweepAngle, true, paintArc);
    }

    private static class Result {
        int startAngle;
        int sweepAngle;
        int color;
        boolean needMove;
        String name;

        Result(int startAngle, int sweepAngle, String color, String name) {
            this.startAngle = startAngle;
            this.sweepAngle = sweepAngle;
            this.color = Color.parseColor(color);
            this.name = name;
        }

        float getHalfAngle() {
            return sweepAngle / 2 + startAngle;
        }

        Result setNeedMove(boolean needMove) {
            this.needMove = needMove;
            return this;
        }
    }
}