开局一张图，先看看是不是想要的效果
没错，今天就要实现这种效果，首先，可以看出来，这个效果是由两部分组成的，滑动的view以及背景view.重点就是滑动的View,并且分两种情况，当滑动距离超过一半时，则顺势滑下去，没有超过一半，则回弹到初始位置。
对于View跟随手势去滑动，当然是ViewDragHelper是比较合适的。我对这个类我也是第一次用，里面还有很多东西没有理解，只是简单的去运用。主要是自定义View继承自LinearLayout.
贴代码，不多BB，看会应该都能懂。
public class SlideRightViewDragHelper extends LinearLayout {private ViewDragHelper viewDragHelper;private View child;private Point childPosition = new Point();private Point childEndPosition = new Point();private OnReleasedListener onReleasedListener;private int oldX;public SlideRightViewDragHelper(Context context, AttributeSet attrs) {super(context, attrs);}public void setTouchable(boolean isTouch) {if (isTouch) {//新建viewDragHelper ,viewGroup, 灵敏度，回调(子view的移动)viewDragHelper = ViewDragHelper.create(this, 1.0f, new ViewDragHelper.Callback() {@Overridepublic boolean tryCaptureView(View child, int pointerId) {oldX = 0;return true;}@Overridepublic int clampViewPositionHorizontal(View child, int left, int dx) {oldX = left;return Math.max(0, left);}@Overridepublic void onViewReleased(View releasedChild, float xvel, float yvel) {if (oldX > getWidth() / 2) {/**之所以没这么写，是因为在滑到最右边之后，滑动的View就会被释放，我通过layout方法无法将view设置*为复原，然后我必须又要把view在移回最左边，但无法实现向右顺势滑动的效果，反正达不到预期的效果，*后来就自己写了个位移动画，最终实现了想要的效果。*/// viewDragHelper.settleCapturedViewAt(childEndPosition.x, childEndPosition.y);// invalidate(); //必须刷新,因为其内部使用的是mScroller.startScroll，所以别忘了需要invalidate()以及结合computeScroll方法一起。// if (onReleasedListener != null) {// child.layout(childPosition.x, childPosition.y, getWidth(), getHeight());// viewDragHelper.settleCapturedViewAt(childPosition.x, childPosition.y); //反弹// onReleasedListener.onReleased();// }TranslateAnimation translateAnimation = new TranslateAnimation(0, childEndPosition.x, childPosition.y, childPosition.y);translateAnimation.setDuration(300);child.startAnimation(translateAnimation);translateAnimation.setAnimationListener(new Animation.AnimationListener() {@Overridepublic void onAnimationStart(Animation animation) {}@Overridepublic void onAnimationEnd(Animation animation) {Handler handler = new Handler();handler.postDelayed(new Runnable() {@Overridepublic void run() {onReleasedListener.onReleased(0, 0, getWidth(), getHeight());}}, 10);}@Overridepublic void onAnimationRepeat(Animation animation) {}});} else {//滑动距离不够一半，回到初始位置viewDragHelper.settleCapturedViewAt(childPosition.x, childPosition.y); //反弹invalidate();//必须调用}super.onViewReleased(releasedChild, xvel, yvel);}@Overridepublic void onViewCaptured(View capturedChild, int activePointerId) {super.onViewCaptured(capturedChild, activePointerId);}@Overridepublic void onViewPositionChanged(View changedView, int left, int top, int dx, int dy) {super.onViewPositionChanged(changedView, left, top, dx, dy);}});} else {viewDragHelper = ViewDragHelper.create(this, 1.0f, new ViewDragHelper.Callback() {@Overridepublic boolean tryCaptureView(View child, int pointerId) {return false;}});}}@Overrideprotected void onFinishInflate() {super.onFinishInflate();child = getChildAt(0);}@Override //用viewDragHelper拦截-truepublic boolean onInterceptTouchEvent(MotionEvent ev) {return viewDragHelper.shouldInterceptTouchEvent(ev);}@Override //viewDragHelper拦截事件public boolean onTouchEvent(MotionEvent event) {viewDragHelper.processTouchEvent(event);return true;}@Overrideprotected void onLayout(boolean changed, int l, int t, int r, int b) {super.onLayout(changed, l, t, r, b);//定位左侧的坐标childPosition.x = child.getLeft();childPosition.y = child.getTop();//定位右侧的坐标childEndPosition.x = child.getRight();childEndPosition.y = child.getTop();}@Overridepublic void computeScroll() {puteScroll();if (viewDragHelper.continueSettling(true)) {invalidate();}}public void setOnReleasedListener(OnReleasedListener onReleasedListener) {this.onReleasedListener = onReleasedListener;}public interface OnReleasedListener {void onReleased(int left, int top, int right, int bottom);}}
主要重写了ViewDragHelper的三个方法
tryCaptureView()试图要捕捉的View 当返回true时，可对当前View进行操作，返回false,则不可操作
clampViewPositionHorizontal() 在水平滑动过程中，可以得到当前View的left值
onViewReleased() 当手指抬起的时候回走这个方法，但我总觉得当我滑到最右边的时候，就会把我的View给释放掉，这个方法还不是很懂
当View滑动到最右边时，就会通过接口告知Activity当前view已经滑到最右边，实现这个接口，并作出对应的操作。
dragHelper.setOnReleasedListener(new SlideRightViewDragHelper.OnReleasedListener() {@Overridepublic void onReleased(final int left, final int top, final int right, final int bottom) {//自己的操作}});
把所有代码都贴一下
布局代码
<RelativeLayoutandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_centerInParent="true"><Buttonandroid:id="@+id/slide_view_bt"android:layout_width="@dimen/x80"android:layout_height="@dimen/x60"android:text="上线" /><com.gengchao.test_slideView.SlideRightViewDragHelperandroid:id="@+id/slide_view_drag_helper"android:layout_width="match_parent"android:layout_height="@dimen/x60"android:layout_marginRight="@dimen/x10"android:layout_toRightOf="@+id/slide_view_bt"android:background="@color/colorPrimary"android:orientation="horizontal"><LinearLayoutandroid:id="@+id/slide_view_ll"android:layout_width="match_parent"android:layout_height="match_parent"android:background="@color/gray"android:orientation="horizontal"><ImageViewandroid:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_gravity="center"android:layout_marginLeft="20dp"android:src="@mipmap/ic_launcher"android:visibility="gone" /><TextViewandroid:id="@+id/slide_view_tv"android:layout_width="0dp"android:layout_height="wrap_content"android:layout_gravity="center"android:layout_marginLeft="10dp"android:layout_weight="1"android:gravity="center"android:text=">>滑动开始听单"android:textColor="@color/white"android:textStyle="bold" /><TextViewandroid:id="@+id/get_order_tv_left_time"android:layout_width="wrap_content"android:layout_height="wrap_content"android:layout_gravity="center"android:layout_marginRight="15dp"android:text="确认（30s）"android:textColor="@color/white"android:textStyle="bold"android:visibility="gone" /></LinearLayout></com.gengchao.test_slideView.SlideRightViewDragHelper></RelativeLayout>
Activity代码
public class SlideViewActivity extends AppCompatActivity implements View.OnClickListener {SlideRightViewDragHelper dragHelper;LinearLayout llSlideBg;TextView tv;Button bt;boolean onLine = false;//false为离线 true为在线boolean orderState = false; //false为未接单 true为接单@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_slide_view);initView();dragHelper.setOnReleasedListener(new SlideRightViewDragHelper.OnReleasedListener() {@Overridepublic void onReleased(final int left, final int top, final int right, final int bottom) {if (orderState == true) {//可接单状态——>不可接单状态orderState = !orderState;llSlideBg.setBackgroundColor(getResources().getColor(R.color.red));} else {//不可接单状态——>可接单状态orderState = !orderState;llSlideBg.setBackgroundColor(getResources().getColor(R.color.colorPrimary));}tv.setText(orderState == true ? ">>滑动结束听单" : ">>滑动开始听单");dragHelper.setBackgroundColor(orderState == true ? getResources().getColor(R.color.red) : getResources().getColor(R.color.colorPrimary));llSlideBg.layout(left, top, right, bottom);}});}private void initView() {llSlideBg = findViewById(R.id.slide_view_ll);tv = findViewById(R.id.slide_view_tv);bt = findViewById(R.id.slide_view_bt);dragHelper = findViewById(R.id.slide_view_drag_helper);bt.setOnClickListener(this);dragHelper.setTouchable(false);}@Overridepublic void onClick(View v) {switch (v.getId()) {case R.id.slide_view_bt:if (onLine) {//当前为上线 去下线onLine = !onLine;llSlideBg.setBackgroundColor(getResources().getColor(R.color.gray));dragHelper.setBackgroundColor(getResources().getColor(R.color.colorPrimary));bt.setText("上线");dragHelper.setTouchable(false);tv.setText(">>滑动开始听单");dragHelper.recovery(llSlideBg);} else {//当前为下线 去上线onLine = !onLine;llSlideBg.setBackgroundColor(getResources().getColor(R.color.red));dragHelper.setBackgroundColor(getResources().getColor(R.color.colorPrimary));bt.setText("下线");dragHelper.setTouchable(true);}break;}}}
到这里就结束了，这种功能也不是很难，前提是一定要多实践才行。加油
