按照@Andrew方法，如果你想要移动视图的中心，你只需要减去视图的一半高度和一半宽度。

float dX, dY;

@Override
public boolean onTouchEvent(View view, MotionEvent event) {
    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            dX = view.getX() - event.getRawX();
            dY = view.getY() - event.getRawY();
            break;
        case MotionEvent.ACTION_MOVE:
            view.animate()
                .x(event.getRawX() + dX - (view.getWidth() / 2f))
                .y(event.getRawY() + dY - (view.getHeight() / 2f))
                .setDuration(0)
                .start();
            break;
        default:
            return false;
    }
    return true;
}     

按照@Andrew方法，如果你想要移动视图的中心，你只需要减去视图的一半高度和一半宽度。

float dX, dY;

@Override
public boolean onTouchEvent(View view, MotionEvent event) {
    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
            dX = view.getX() - event.getRawX();
            dY = view.getY() - event.getRawY();
            break;
        case MotionEvent.ACTION_MOVE:
            view.animate()
                .x(event.getRawX() + dX - (view.getWidth() / 2f))
                .y(event.getRawY() + dY - (view.getHeight() / 2f))
                .setDuration(0)
                .start();
            break;
        default:
            return false;
    }
    return true;
}     

我推荐使用view。translationX和view。翻译来移动你的观点。

Kotlin snippet:

yourView.translationX = xTouchCoordinate
yourView.translationY = yTouchCoordinate

创建一个自定义的触摸监听器类(在Kotlin中):

(这段代码限制了视图从父视图中拖出)

class CustomTouchListener(
  val screenWidth: Int, 
  val screenHeight: Int
) : View.OnTouchListener {
    private var dX: Float = 0f
    private var dY: Float = 0f

    override fun onTouch(view: View, event: MotionEvent): Boolean {

        val newX: Float
        val newY: Float

        when (event.action) {
            MotionEvent.ACTION_DOWN -> {
                dX = view.x - event.rawX
                dY = view.y - event.rawY
            }
            MotionEvent.ACTION_MOVE -> {

                newX = event.rawX + dX
                newY = event.rawY + dY

                if ((newX <= 0 || newX >= screenWidth - view.width) || (newY <= 0 || newY >= screenHeight - view.height)) {
                    return true
                }

                view.animate()
                    .x(newX)
                    .y(newY)
                    .setDuration(0)
                    .start()
            }
        }
        return true
    }
}

如何使用它?

parentView.viewTreeObserver.addOnGlobalLayoutListener { view.setOnTouchListener(CustomTouchListener(parentView.width, parentView.height)) }

parentView是视图的父视图。

改变了一点由@Vyacheslav Shylkin提供的解决方案，以删除手动输入数字的依赖性。

import android.app.Activity;
import android.os.Bundle;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewTreeObserver;
import android.widget.ImageView;
import android.widget.RelativeLayout;

public class MainActivity extends Activity implements View.OnTouchListener
{
    private int       _xDelta;
    private int       _yDelta;
    private int       _rightMargin;
    private int       _bottomMargin;
    private ImageView _floatingView;

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        this._floatingView = (ImageView) findViewById(R.id.textView);

        this._floatingView.getViewTreeObserver().addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener()
        {
            @Override
            public boolean onPreDraw()
            {
                if (_floatingView.getViewTreeObserver().isAlive())
                    _floatingView.getViewTreeObserver().removeOnPreDrawListener(this);

                updateLayoutParams(_floatingView);
                return false;
            }
        });

        this._floatingView.setOnTouchListener(this);
    }

    private void updateLayoutParams(View view)
    {
        this._rightMargin = -view.getMeasuredWidth();
        this._bottomMargin = -view.getMeasuredHeight();

        RelativeLayout.LayoutParams layoutParams = new RelativeLayout.LayoutParams(view.getMeasuredWidth(), view.getMeasuredHeight());
        layoutParams.bottomMargin = this._bottomMargin;
        layoutParams.rightMargin = this._rightMargin;

        view.setLayoutParams(layoutParams);
    }

    @Override
    public boolean onTouch(View view, MotionEvent event)
    {
        if (view == this._floatingView)
        {
            final int X = (int) event.getRawX();
            final int Y = (int) event.getRawY();

            switch (event.getAction() & MotionEvent.ACTION_MASK)
            {
                case MotionEvent.ACTION_DOWN:
                    RelativeLayout.LayoutParams lParams = (RelativeLayout.LayoutParams) view.getLayoutParams();
                    this._xDelta = X - lParams.leftMargin;
                    this._yDelta = Y - lParams.topMargin;
                    break;

                case MotionEvent.ACTION_MOVE:
                    RelativeLayout.LayoutParams layoutParams = (RelativeLayout.LayoutParams) view.getLayoutParams();
                    layoutParams.leftMargin = X - this._xDelta;
                    layoutParams.topMargin = Y - this._yDelta;
                    layoutParams.rightMargin = this._rightMargin;
                    layoutParams.bottomMargin = this._bottomMargin;
                    view.setLayoutParams(layoutParams);
                    break;
            }

            return true;
        }
        else
        {
            return false;
        }
    }
}

在Kotlin中实现相同

    rightPanel.setOnTouchListener(View.OnTouchListener { view, event ->
        when (event?.action) {
            MotionEvent.ACTION_DOWN -> {

                rightDX = view!!.x - event.rawX
                // rightDY = view!!.getY() - event.rawY;

            }
            MotionEvent.ACTION_MOVE -> {

                var displacement = event.rawX + rightDX

                view!!.animate()
                        .x(displacement)
                        // .y(event.getRawY() + rightDY)
                        .setDuration(0)
                        .start()
            }
            else -> { // Note the block
                return@OnTouchListener false
            }
        }
        true
 })