我正在开发一个操纵杆按钮。在围绕圆圈移动时一切都很好，但是当我想要向上或向下移动它时，它从右侧再次绕圈。所以，我想要两个选项（像真正的操纵杆一样向上或向下移动）。这是我的代码示例。谢谢你的帮助
public class JoystickView extends FrameLayout implements View.OnTouchListener {
private Context context;
private ImageView backgroundImageView;
private ImageView buttonImageView;
private RelativeLayout relativeLayout;
private View rootView;
float xx = 0;
float yy = 0;
public JoystickView(Context context) {
super(context);
this.context = context;
setLayout(this);
buttonImageView.setOnTouchListener(this);
this.setClipChildren(false);
}
public void setLayout(ViewGroup view) {
FrameLayout.LayoutParams layoutParams = new FrameLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);
View v = inflateControlerLayout();
view.addView(v, layoutParams);
}
protected View inflateControlerLayout() {
initSlider();
rootView = relativeLayout;
return rootView;
}
public void initSlider() {
if (relativeLayout == null) {
relativeLayout = new RelativeLayout(context);
RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.MATCH_PARENT, RelativeLayout.LayoutParams.MATCH_PARENT);
relativeLayout.setLayoutParams(layoutParams);
relativeLayout.setClipChildren(false);
}
if (backgroundImageView == null) {
backgroundImageView = new ImageView(context);
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT);
backgroundImageView.setLayoutParams(layoutParams);
// load image
try {
// get input stream
InputStream ims = getContext().getAssets().open("joystick_background.png");
// load image as Drawable
Drawable d = Drawable.createFromStream(ims, null);
// set image to ImageView
backgroundImageView.setImageDrawable(d);
} catch (IOException ex) {
return;
}
}
if (buttonImageView == null) {
buttonImageView = new ImageView(context);
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT, Gravity.CENTER);
buttonImageView.setLayoutParams(layoutParams);
// load image
try {
// get input stream
InputStream ims2 = getContext().getAssets().open("jostick_button.png");
// load image as Drawable
Drawable d2 = Drawable.createFromStream(ims2, null);
// set image to ImageView
buttonImageView.setImageDrawable(d2);
buttonImageView.bringToFront();
} catch (IOException ex) {
return;
}
}
if (relativeLayout != null) {
relativeLayout.addView(backgroundImageView);
relativeLayout.addView(buttonImageView);
}
}
@Override
public boolean onTouch(View view, MotionEvent motionEvent) {
switch (motionEvent.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
break;
case MotionEvent.ACTION_UP:
view.setX(xx);
view.setY(yy);
break;
case MotionEvent.ACTION_POINTER_DOWN:
break;
case MotionEvent.ACTION_POINTER_UP:
break;
case MotionEvent.ACTION_MOVE:
float cx = view.getWidth() / 2.f;
float cy = view.getHeight() / 2.f;
float x = motionEvent.getRawX();
float y = motionEvent.getRawY();
float w = buttonImageView.getWidth();
float h = buttonImageView.getHeight();
double r = Math.min(cx, cy) / 2.;
double dx = x - cx;
double dy = y - cy;
double hypot = Math.hypot(dx, dy);
double cos = dx / hypot;
double sin = dy / hypot;
double rdx = hypot < 1. ? 0. : r * cos;
double rdy = hypot < 1. ? 0. : r * sin;
buttonImageView.setTranslationX((float) (cx + rdx - w / 2.));
buttonImageView.setTranslationY((float) (cy + rdy - h / 2.));
break;
}
return true;
}
}
答案 0 :(得分：1)
这些线将坐标约束为圆（椭圆）路径或中心：
double rdx = hypot < 1. ? 0. : r * cos;
double rdy = hypot < 1. ? 0. : r * sin;
如果hypot小于1（即1个像素），您必须处于死亡中心。
我将其更改为仅约束圆圈内的坐标：
double rcos = r * cos;
double rsin = r * sin;
double rdx = Math.abs(dx) < Math.abs(rcos) ? dx : rcos;
double rdy = Math.abs(dy) < Math.abs(rsin) ? dy : rsin;
我认为这可能就是你想要的。
答案 1 :(得分：0)
如果有人正在寻找，我找到了一个有效的解决方案
私人Point计算（float x，float y）{
float cx = buttonImageView.getWidth() / 2.f;
float cy = buttonImageView.getHeight() / 2.f;
double r = cx / 2.; // vrednost radius
double dx = x;
double dy = y;
double hypot = Math.hypot(dx, dy); // izracun hipotenuze
double cos = dx / hypot; // cos
double sin = dy / hypot; // sin
double rcos = r * cos;
double rsin = r * sin;
double rdx = Math.abs(dx) < Math.abs(rcos) ? dx : rcos; // if,else
double rdy = Math.abs(dy) < Math.abs(rsin) ? dy : rsin;
return new Point((int)rdx, (int)rdy);
}
@Override
public boolean onTouch(View view, MotionEvent motionEvent) {
final float x = motionEvent.getRawX(); // x točko
final float y = motionEvent.getRawY(); // y točka
//Log.d("VALUES", "RAW X:" + motionEvent.getRawX() + ", RAW Y:" + motionEvent.getRawY() + ", X:" + motionEvent.getX() + ", CX:" + cx + ", CY:" + cy + ", dx:" + dx + ", dy:" + dy + ", Hypo:" + hypot + ", cos:" + cos + ", sin" + sin);
switch (motionEvent.getAction() & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
xDelta = view.getX() - x;
yDelta = view.getY() - y;
break;
case MotionEvent.ACTION_UP:
doBounceAnimation(buttonImageView);
doVibration();
view.setX(xx);
view.setY(yy);
break;
case MotionEvent.ACTION_POINTER_DOWN:
break;
case MotionEvent.ACTION_POINTER_UP:
break;
case MotionEvent.ACTION_MOVE:
final float transX = (float) x;
final float transY = (float) y;
thread = new Thread() {
@Override
public void run() {
Point newPoint = calculate(transX+ xDelta,transY + yDelta);
buttonImageView.setX(newPoint.x);
buttonImageView.setY(newPoint.y);
}
};
thread.start();
Log.d(TRANSLATIONX,"X:" + transX + ", Y:" + transY);
break;
}
return true;
}
享受编码！