1.使用接口: 定义:
private AutoScrollViewPager autoScrollViewPager ; private CustomPagerAdapter pagerAdapter;使用autoScrollViewPager :
pagerAdapter = new CustomPagerAdapter(drawbleDatas,this); autoScrollViewPager = (AutoScrollViewPager)findViewById(R.id.view_pager); autoScrollViewPager.setAdapter(pagerAdapter); autoScrollViewPager.startAutoScroll(); autoScrollViewPager.setInterval(2000); autoScrollViewPager.setCycle(true); autoScrollViewPager.setSwipeScrollDurationFactor(1); autoScrollViewPager.setAutoScrollDurationFactor(0.01);2.自定义CustomDurationScroller类: 此类主要是覆盖方法startScroll和setScrollDurationFactor。
3.自定义AutoScrollViewPager类,继承自ViewPager 在此类中,我们关键是实现二点,一是定时显示下一个界面。 这个其实是比较简单实现的,我们定义一个handler,定时的发送消息来显示下一个界面,关键代码:
private static class MyHandler extends Handler { private final WeakReference<AutoScrollViewPager> autoScrollViewPager; public MyHandler(AutoScrollViewPager autoScrollViewPager) { this.autoScrollViewPager = new WeakReference<AutoScrollViewPager>(autoScrollViewPager); } @Override public void handleMessage(Message msg) { super.handleMessage(msg); switch (msg.what) { //这就是viewpagerqieh切换到下一个界面的消息 case SCROLL_WHAT: //Log.i(TAG,"handleMessage---SCROLL_WHAT"); AutoScrollViewPager pager = this.autoScrollViewPager.get(); if (pager != null) { pager.scroller.setScrollDurationFactor(pager.autoScrollFactor); pager.scrollOnce(); pager.scroller.setScrollDurationFactor(pager.swipeScrollFactor); pager.sendScrollMessage(pager.interval + pager.scroller.getDuration()); } break; default: break; } } }具体viewpagerqieh切换到下一个界面的逻辑是:
public void scrollOnce() { PagerAdapter adapter = getAdapter(); int currentItem = getCurrentItem(); int totalCount; if (adapter == null || (totalCount = adapter.getCount()) <= 1) { return; } int nextItem = (direction == LEFT) ? --currentItem : ++currentItem; if (nextItem < 0) { if (isCycle) { setCurrentItem(totalCount - 1, isBorderAnimation); } } else if (nextItem == totalCount) { if (isCycle) { setCurrentItem(0, isBorderAnimation); } } else { setCurrentItem(nextItem, true); } }第二个关键是处理我们手动的滑动事件,这主要是方法dispatchTouchEvent来实现。
1.android-auto-scroll-view-pager https://github.com/Trinea/android-auto-scroll-view-pager