可拖动的组件，可更改为其它View

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可拖动的组件，可更改为其它View

效果图

参考图

自定义View源码

DragTextView


package com.demo.drag;import android.content.Context;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.ViewGroup;
import android.widget.RelativeLayout;/*** Created by talon on 2020/5/21* note: 可拖动的View，这里是TextView，可以换成其他的View* 解决了更新视图时，该View坐标会重置的问题*/
public class DragTextView extends android.support.v7.widget.AppCompatTextView {private final String TAG = "MyDragTextView";private int mLastX;private int mLastY;RelativeLayout.LayoutParams params;public DragTextView(Context context) {super(context);}public DragTextView(Context context, AttributeSet attrs) {super(context, attrs);}public DragTextView(Context context, AttributeSet attrs, int defStyleAttr) {super(context, attrs, defStyleAttr);}@Overridepublic boolean onTouchEvent(MotionEvent event) {int parentWidth = ((ViewGroup) getParent()).getWidth();int parentHeight = ((ViewGroup) getParent()).getHeight();int x = (int) event.getRawX();int y = (int) event.getRawY();// 注意：xx.LayoutParams这里的xx应该是该组件的父布局类型// 注意：这句话必须在该组件已经添加到父布局中才会起作用，所以这句话我没有写在构造函数中，而是写在这里params = (RelativeLayout.LayoutParams) this.getLayoutParams();switch (event.getAction()) {case MotionEvent.ACTION_DOWN:mLastX = x;mLastY = y;break;case MotionEvent.ACTION_MOVE:int offSetX = x - mLastX;int offSetY = y - mLastY;// 限制边界。int left = getLeft() + offSetX;if (left<0)left = 0;if (left>(parentWidth-getWidth()))left = parentWidth-getWidth();int top = getTop() + offSetY;if (top<0)top = 0;if (top>(parentHeight-getHeight()))top= parentHeight-getHeight();int right = getRight() + offSetX;if (right<getWidth())right = getWidth();if (right>parentWidth)right = parentWidth;int bottom = getBottom() + offSetY;if (bottom<getHeight())bottom = getHeight();if (bottom>parentHeight)bottom = parentHeight;//                LogWrapper.e(TAG,"left:"+left+"_top:"+top+"_right："+right+"_bottom:"+bottom);// 1.（不限制滑动范围）调用layout方法来重新放置它的位置
//                layout(getLeft() + offSetX, getTop() + offSetY, getRight() + offSetX, getBottom() + offSetY);// 2. （限制滑动范围）layout(left, top, right, bottom);mLastX = x;mLastY = y;break;case MotionEvent.ACTION_UP:
//                int screenWidth = ScreenUtils.getScreenWidth(getContext());
//                int screenHeight = ScreenUtils.getScreenHeight(getContext());// 左上右下 的 margin，后面两个参数必须要设置，不然在边界处可能会引起图片的变形params.setMargins(getLeft(), getTop(), parentWidth - (getLeft() + getWidth()), parentHeight - (getTop() + getHeight()));setLayoutParams(params);break;default:break;}return true;}
}