Question

我无法在ontouch（）中获取画布对象。没有画布我触摸时无法绘制圆形。触摸时如何绘制任何形状或图像

public class Board extends View implements View.OnTouchListener {

public Board(Context context) {
    super(context);
    Paint paint1 = new Paint();
    paint1.setTextSize(50);
    paint1.setColor(Color.WHITE);

    View view=this;
    view.setOnTouchListener(this);    
}

@Override
public void onDraw(Canvas canvas) {
    super.onDraw(canvas);
    canvas.drawRGB(200, 100, 0);

}

@Override
public boolean onTouch(View v, MotionEvent event) {
    final int action = MotionEventCompat.getActionMasked(event);
    int pointer = MotionEventCompat.getActionIndex(event);


    if (action == MotionEvent.ACTION_DOWN) {

         canvas.drawCircle(70, 1100, 50, paint1);

    }

    return false;
}

Answer 1

要在任何地方触摸画布，您需要一条路径来跟踪您的触摸点和路径。使用路径对象，您可以在画布上绘制。请参阅此回答Draw on touch

触摸时如何在画布上绘画

1 个答案: