gistfile1.txt

package com.example.zeus.neatometer;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;

import java.util.ArrayList;

public class SketchView extends View {

    private Path drawingPath;
    private Paint canvasPaint;
    private Paint drawingPaint;
    private Canvas drawingCanvas;
    private Bitmap canvasBitmap;

    private float xcoor, ycoor;

    private static final int PAINT_COLOR = 0xFF000000;
    private static final float BRUSH_SIZE = 6;
    private static final float TOUCH_TOLERANCE = 4;

    private ArrayList<Path> paths;
    private ArrayList<Path> undonePaths;

    private void init() {
        drawingPath = new Path();
        drawingPaint = new Paint();
        drawingPaint.setColor(PAINT_COLOR);
        drawingPaint.setAntiAlias(true);
        drawingPaint.setStrokeWidth(BRUSH_SIZE);
        drawingPaint.setStyle(Paint.Style.STROKE);
        drawingPaint.setStrokeJoin(Paint.Join.ROUND);
        drawingPaint.setStrokeCap(Paint.Cap.ROUND);

        canvasPaint = new Paint(Paint.DITHER_FLAG);

        paths = new ArrayList<>();
        undonePaths = new ArrayList<>();
    }

    public SketchView(Context context, AttributeSet attributeSet) {
        super(context, attributeSet);
        init();
    }

    @Override
    protected void onDraw(Canvas canvas) {
        for (Path p:paths) {
            canvas.drawPath(p, drawingPaint);
        }
        canvas.drawPath(drawingPath, drawingPaint);
    }

    @Override
    protected void onSizeChanged(int w, int h, int oldw, int oldh) {
        super.onSizeChanged(w, h, oldw, oldh);
        canvasBitmap = Bitmap.createBitmap(w, h, Bitmap.Config.ARGB_8888);
        drawingCanvas = new Canvas(canvasBitmap);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        float touchX = event.getX();
        float touchY = event.getY();

        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                touchActionDown(touchX, touchY);
                invalidate();
                break;
            case MotionEvent.ACTION_MOVE:
                touchActionMove(touchX, touchY);
                invalidate();
                break;
            case MotionEvent.ACTION_UP:
                touchActionUp();
                invalidate();
                break;
            default:
                return false;
        }
        return true;
    }

    private void touchActionDown(float x, float y) {
        undonePaths.clear();
        drawingPath.reset();
        drawingPath.moveTo(x, y);
        xcoor = x;
        ycoor = y;
    }

    private void touchActionMove(float x, float y) {
        float dx = Math.abs(x - xcoor);
        float dy = Math.abs(y - ycoor);
        if (dx>=TOUCH_TOLERANCE || dy>=TOUCH_TOLERANCE) {
            drawingPath.quadTo(xcoor, ycoor, (x+xcoor)/2, (y+ycoor)/2);
            xcoor = x;
            ycoor = y;
        }
    }

    private void touchActionUp() {
        drawingPath.lineTo(xcoor, ycoor);
        drawingCanvas.drawPath(drawingPath, drawingPaint);
        paths.add(drawingPath);
        drawingPath = new Path();
    }

    public void onEraseAllPressed() {
        drawingPath = new Path();
        paths.clear();
        drawingCanvas.drawColor(Color.WHITE);
        invalidate();
    }

    public void onUndoPressed() {
        if (paths.size() > 0) {
            undonePaths.add(paths.remove(paths.size()-1));
            invalidate();
        }
    }

    public void onRedoPressed() {
        if (undonePaths.size() > 0) {
            paths.add(undonePaths.remove(undonePaths.size()-1));
            invalidate();
        }
    }

    public Bitmap getSketchAsBitmap() {
        Bitmap bitmap = Bitmap.createBitmap(canvasBitmap.getWidth(), canvasBitmap.getHeight(), Bitmap.Config.ARGB_8888);
        return bitmap;
    }
}