Android 实现ViewPager边界回弹效果实例代码

废话不多说了，直接给大家贴代码了，具体代码如下所示：

public class bouncebackviewpager extends viewpager {
 private int currentposition = 0;
 private rect mrect = new rect();//用来记录初始位置
 private boolean handledefault = true;
 private float prex = 0f;
 private static final float ratio = 0.5f;//摩擦系数
 private static final float scroll_width = 10f;
 public bouncebackviewpager(context context) {
  super(context);
 }
 public bouncebackviewpager(context context, attributeset attrs) {
  super(context, attrs);
 }
 @override
 public boolean dispatchkeyevent(keyevent event) {
  return super.dispatchkeyevent(event);
 }
 @override
 public boolean onintercepttouchevent(motionevent ev) {
  if (ev.getaction() == motionevent.action_down) {
   prex = ev.getx();//记录起点
   currentposition = getcurrentitem();
  }
  return super.onintercepttouchevent(ev);
 }
 @override
 public boolean ontouchevent(motionevent ev) {
  switch (ev.getaction()) {
   case motionevent.action_up:
    ontouchactionup();
    break;
   case motionevent.action_move:
    if (getadapter().getcount() == 1) {
     float nowx = ev.getx();
     float offset = nowx - prex;
     prex = nowx;
     if (offset > scroll_width) {//手指滑动的距离大于设定值
      whetherconditionisright(offset);
     } else if (offset < -scroll_width) {
      whetherconditionisright(offset);
     } else if (!handledefault) {//这种情况是已经出现缓冲区域了，手指慢慢恢复的情况
      if (getleft() + (int) (offset * ratio) != mrect.left) {
       layout(getleft() + (int) (offset * ratio), gettop(), getright() + (int) (offset * ratio), getbottom());
      }
     }
    } else if ((currentposition == 0 || currentposition == getadapter().getcount() - 1)) {
     float nowx = ev.getx();
     float offset = nowx - prex;
     prex = nowx;
     if (currentposition == 0) {
      if (offset > scroll_width) {//手指滑动的距离大于设定值
       whetherconditionisright(offset);
      } else if (!handledefault) {//这种情况是已经出现缓冲区域了，手指慢慢恢复的情况
       if (getleft() + (int) (offset * ratio) >= mrect.left) {
        layout(getleft() + (int) (offset * ratio), gettop(), getright() + (int) (offset * ratio), getbottom());
       }
      }
     } else {
      if (offset < -scroll_width) {
       whetherconditionisright(offset);
      } else if (!handledefault) {
       if (getright() + (int) (offset * ratio) <= mrect.right) {
        layout(getleft() + (int) (offset * ratio), gettop(), getright() + (int) (offset * ratio), getbottom());
       }
      }
     }
    } else {
     handledefault = true;
    }
    if (!handledefault) {
     return true;
    }
    break;
   default:
    break;
  }
  return super.ontouchevent(ev);
 }
 private void whetherconditionisright(float offset) {
  if (mrect.isempty()) {
   mrect.set(getleft(), gettop(), getright(), getbottom());
  }
  handledefault = false;
  layout(getleft() + (int) (offset * ratio), gettop(), getright() + (int) (offset * ratio), getbottom());
 }
 private void ontouchactionup() {
  if (!mrect.isempty()) {
   recoveryposition();
  }
 }
 private void recoveryposition() {
  translateanimation ta = new translateanimation(getleft(), mrect.left, 0, 0);
  ta.setduration(300);
  startanimation(ta);
  layout(mrect.left, mrect.top, mrect.right, mrect.bottom);
  mrect.setempty();
  handledefault = true;
 }
}

以上所述是小编给大家介绍的android 实现viewpager边界回弹效果实例代码，希望对大家有所帮助