アプリケーションで元に戻す機能を実行したい..このために、コードの下で実行したx、yポイントの配列リストを取得することをネットで見つけました。図面を元に戻すことはできません??
public Drawview(Context context, float x, float y, int r) {
super(context);
mBitmap = Bitmap.createBitmap(800, 1200, Bitmap.Config.ARGB_8888);
// mainbitmap.add(mBitmap);
//System.out.println("**mBitmapPaint***"+mBitmapPaint);
mCanvas = new Canvas(mBitmap);
mPath = new Path();
mBitmapPaint = new Paint(Paint.DITHER_FLAG);
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
}
@Override
protected void onDraw(Canvas canvas) {
System.out.println("***Drawinglines****"+Drawinglines);
canvas.drawBitmap(mBitmap, 0, 0, mBitmapPaint);
canvas.drawPath(mPath, mPaint);
}
private float mX, mY;
private static final float TOUCH_TOLERANCE = 4;
private void touch_start(float x, float y) {
mPath.reset();
mPath.moveTo(x, y);
mX = x;
mY = y;
}
private void touch_move(float x, float y) {
float dx = Math.abs(x - mX);
float dy = Math.abs(y - mY);
if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
mPath.quadTo(mX, mY, (x + mX)/2, (y + mY)/2);
mX = x;
mY = y;
}
}
private void touch_up() {
mPath.lineTo(mX, mY);
mCanvas.drawPath(mPath, mPaint);
/// path.
//graphics.add(mPath);
mPath.reset();
}
// events when touching the screen
public boolean onTouchEvent(MotionEvent event) {
event.getAction();
int eventaction = event.getAction();
int X = (int)event.getX();
int Y = (int)event.getY();
switch (eventaction ) {
case MotionEvent.ACTION_DOWN:
{
touch_start(X, Y);
}
invalidate();
break;
case MotionEvent.ACTION_MOVE:
System.out.println("***ACTION_MOVE**************"+X+"************"+Y);
if((Drawinglines.equals("Pen"))||(Drawinglines.equals("Erase")))
{
touch_move(X, Y);
temp_point.add(new Point(X,Y));
}
invalidate();
break;
case MotionEvent.ACTION_UP:
main_Points.add(temp_point);
temp_point = null;
touch_up();
invalidate();
break;
}
return true;
}
public void undopath()
{
main_Points.remove(main_Points.size()-1);
invalidate();
}
}
@Override
public void onClick(View v) {
if(v == Undo)
{
Drawview abc=new Drawview();
abc.undopath();
}
ただし、元に戻す機能は機能していません。