Android简单实现悬浮吸附的FloatingView

/**
* &＃064;ProjectName: yqf-android
* &＃064;Package: com.jao.pointsystem.weight
* &＃064;ClassName: ScrollFloatinigButton
* &＃064;Description: java类作用描述
* &＃064;Author: OlderJiao
* &＃064;CreateDate: 2020/3/24 10:47
* &＃064;UpdateUser: 更新者&＃xff1a;
* &＃064;UpdateDate: 2020/3/24 10:47
* &＃064;Version: 1.0
*/
&＃064;SuppressLint("AppCompatCustomView")
public class ScrollFloatinigButton extends FrameLayout {
private static final String TAG &＃061; "ScrollFloatinigButton";
private float mX;
private float mY;
private int mParentWidth;
private int mParentHeight;
private boolean mScrollEnable &＃061; true;
private int mScrollLeft;
private int mScrollTop;
private int mRight;
private int mScrollRight;
private int mScrollBottom;
private boolean hasScroll;
boolean isScroll &＃061; false;
private boolean isAdsorb &＃061; true;//是否自动吸附到两边
public ScrollFloatinigButton(Context context) {
this(context, null);
}
public ScrollFloatinigButton(Context context, AttributeSet attrs) {
this(context, attrs, 0);
}
public ScrollFloatinigButton(Context context, AttributeSet attrs, final int defStyleAttr) {
super(context, attrs, defStyleAttr);
TypedArray ta &＃061; context.obtainStyledAttributes(attrs, R.styleable.ScrollFloatinigView);
mScrollEnable &＃061; ta.getBoolean(R.styleable.ScrollFloatinigView_scrollEnable, true);
ta.recycle();
}
&＃064;Override
protected void onAttachedToWindow() {
super.onAttachedToWindow();
//防止布局重置时重置ScrollFloatinigView的位置
ViewParent parent &＃061; getParent();
if (parent instanceof ViewGroup) {
((ViewGroup) getParent()).addOnLayoutChangeListener(new OnLayoutChangeListener() {
&＃064;Override
public void onLayoutChange(View v, int left, int top, int right, int bottom, int oldLeft, int oldTop, int oldRight, int oldBottom) {
if (hasScroll && mScrollRight !&＃061; 0 && mScrollBottom !&＃061; 0)
layout(mScrollLeft, mScrollTop, mScrollRight, mScrollBottom);
}
});
}
}
&＃064;Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
if (getParent() instanceof ViewGroup) {
mParentWidth &＃061; ((ViewGroup) getParent()).getWidth();
mParentHeight &＃061; ((ViewGroup) getParent()).getHeight();
}
Log.i(TAG, "onSizeChanged: ");
}
&＃064;Override
public boolean onTouchEvent(MotionEvent ev) {
if (!mScrollEnable) return super.onTouchEvent(ev);
switch (ev.getAction()) {
case MotionEvent.ACTION_DOWN:
mX &＃061; ev.getX();
mY &＃061; ev.getY();
super.onTouchEvent(ev);
return true;
case MotionEvent.ACTION_MOVE:
int scaledTouchSlop &＃061; ViewConfiguration.get(getContext()).getScaledTouchSlop();
float x &＃061; ev.getX();
float y &＃061; ev.getY();
x &＃061; x - mX;
y &＃061; y - mY;
if (Math.abs(scaledTouchSlop) < Math.abs(x) || Math.abs(scaledTouchSlop) < Math.abs(y)) {
isScroll &＃061; true;
}
if (isScroll) {
mScrollLeft &＃061; (int) (getX() &＃043; x);
mScrollTop &＃061; (int) (getY() &＃043; y);
mScrollRight &＃061; (int) (getX() &＃043; getWidth() &＃043; x);
mScrollBottom &＃061; (int) (getY() &＃043; getHeight() &＃043; y);
//防止滑出父界面
if (mScrollLeft < 0 || mScrollRight > mParentWidth) {
mScrollLeft &＃061; (int) getX();
mScrollRight &＃061; (int) getX() &＃043; getWidth();
}
if (mScrollTop < 0 || mScrollBottom > mParentHeight) {
mScrollTop &＃061; (int) getY();
mScrollBottom &＃061; (int) getY() &＃043; getHeight();
}
layout(mScrollLeft, mScrollTop, mScrollRight, mScrollBottom);
hasScroll &＃061; true;
return true;
}
break;
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_CANCEL:
if (isScroll) {
isScroll &＃061; false;
setPressed(false);//重置点击状态
if (isAdsorb) {//判断是否开启吸附
//获取屏幕中间值
int mind &＃061; getScreenWidth() / 2;
//获取控件宽度的中间值
int viewWithMind &＃061; getWidth() / 2;
//手指抬起时 自动吸附到屏幕两边
if (mScrollLeft &＃043; viewWithMind > mind) {
mScrollRight &＃061; getScreenWidth();
mScrollLeft &＃061; getScreenWidth() - getWidth();
} else {
mScrollRight &＃061; getWidth();
mScrollLeft &＃061; 0;
}
layout(mScrollLeft, mScrollTop, mScrollRight, mScrollBottom);
}
return true;
}
break;
}
return super.onTouchEvent(ev);
}
public boolean isAdsorb() {
return isAdsorb;
}
public void setAdsorb(boolean adsorb) {
isAdsorb &＃061; adsorb;
}
/**
* 得到屏幕宽度
*
* &＃064;return
*/
private int getScreenWidth() {
WindowManager windowManager &＃061; (WindowManager) getContext().getSystemService(Context.WINDOW_SERVICE);
DisplayMetrics displayMetrics &＃061; new DisplayMetrics();
windowManager.getDefaultDisplay().getMetrics(displayMetrics);
return displayMetrics.widthPixels;
}
}


布局代码&＃xff0c;引用一下控件就OK了

<androidx.constraintlayout.widget.ConstraintLayout xmlns:android&＃061;"http://schemas.android.com/apk/res/android"
xmlns:app&＃061;"http://schemas.android.com/apk/res-auto"
xmlns:tools&＃061;"http://schemas.android.com/tools"
android:layout_width&＃061;"match_parent"
android:layout_height&＃061;"match_parent"
tools:context&＃061;".ZoomActivity">
<com.example.test.widget.ScrollFloatinigButton
android:layout_width&＃061;"100dp"
android:layout_height&＃061;"150dp"
android:layout_marginRight&＃061;"20dp"
android:layout_marginBottom&＃061;"50dp"
android:background&＃061;"&＃064;color/gray"
app:layout_constraintBottom_toBottomOf&＃061;"parent"
app:layout_constraintRight_toRightOf&＃061;"parent" />
androidx.constraintlayout.widget.ConstraintLayout>


自定义的属性

<declare-styleable name&＃061;"ScrollFloatinigView">
<attr name&＃061;"scrollEnable" format&＃061;"boolean" />
declare-styleable>


有问题欢迎指正&＃xff0c;共同学习&＃xff0c;共同进步

本文地址：https://blog.csdn.net/qq_44946212/article/details/110648463