android中的2个手指旋转手势监听器
我试图找出最好的方法,让一个图像随着用户的手指向左或向右拖动而旋转,以及旋转角度android中的2个手指旋转手势监听器,android,android-gesture,Android,Android Gesture,我试图找出最好的方法,让一个图像随着用户的手指向左或向右拖动而旋转,以及旋转角度 float x1 = lastEvent[0] - lastEvent[1]; float y1 = lastEvent[2] - lastEvent[3]; float degrees1 = (float)(Math.atan2(y1, x1)); float x2 = event.getX(0) - event.getX(1); float y2 = event.getY(0) - even
float x1 = lastEvent[0] - lastEvent[1];
float y1 = lastEvent[2] - lastEvent[3];
float degrees1 = (float)(Math.atan2(y1, x1));
float x2 = event.getX(0) - event.getX(1);
float y2 = event.getY(0) - event.getY(1);
float degrees2 = (float)(Math.atan2(y2, x2));
float degrees = (float) Math.toDegrees(degrees2-degrees1);
但它不会像我想要的那样旋转。。有旋转手势的听者吗?谢谢如果您正在寻找一个好的解释,这将非常有用。
/** Determine the degree between the first two fingers */
private float rotation(MotionEvent event) {
double delta_x = (event.getX(0) - event.getX(1));
double delta_y = (event.getY(0) - event.getY(1));
double radians = Math.atan2(delta_y, delta_x);
if (Constant.TRACE) Log.d("Rotation ~~~~~~~~~~~~~~~~~", delta_x+" ## "+delta_y+" ## "+radians+" ## "
+Math.toDegrees(radians));
return (float) Math.toDegrees(radians);
}
通过使用此库,您可以创建一个包,并将/通过SandboxView、TouchManager和Vector2D类复制到该包中
然后,将FrameLayout添加到xml文件(而不是imageView)中,并将其链接到代码
最后,使用以下代码将位图添加到布局中:
try {
Bitmap bitmap = MediaStore.Images.Media.getBitmap(mContext.getContentResolver(), mUserImgUri);
sandboxView = new SandboxView(mContext, bitmap);
sandboxView.setLayoutParams(new FrameLayout.LayoutParams(
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT));
sandboxView.setVisibility(View.INVISIBLE);
frameLayout.addView(sandboxView);
} catch (IOException e) {
e.printStackTrace();
}