遇到的问题描述:
嵌套后ViewPager中的view展示不出来,解决办法:重新设置Viewpager的高度
自定义viewpager
public class WrapViewPager extends ViewPager { private int current; private int height = 0; /** * 保存position与对于的View */ private HashMap<Integer, View> childrenViews = new LinkedHashMap(); private boolean isCanScroll = false; public WrapViewPager(Context context) { super(context, null); } public WrapViewPager(Context context, AttributeSet attrs) { super(context, attrs); } public void setScanScroll(boolean isCanScroll) { this.isCanScroll = isCanScroll; }
//切换tab的时候重新设置viewpager的高度 public void resetHeight(int current) { this.current = current; if (childrenViews.size() > current) { LinearLayout.LayoutParams layoutParams = (LinearLayout.LayoutParams) getLayoutParams(); if (layoutParams == null) { layoutParams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, height); } else { layoutParams.height = height; } setLayoutParams(layoutParams); } } /** * 保存position与对于的View */ public void setObjectForPosition(View view, int position) { childrenViews.put(position, view); } @Override public void scrollTo(int x, int y) { super.scrollTo(x, y); } @Override public boolean onTouchEvent(MotionEvent arg0) { try { if (isCanScroll) { return super.onTouchEvent(arg0); } } catch (Exception e) { } return false; } @Override public boolean onInterceptTouchEvent(MotionEvent arg0) { try { if (isCanScroll) { return super.onInterceptTouchEvent(arg0); } } catch (Exception e) { } return false; } @Override protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) { super.onMeasure(widthMeasureSpec, heightMeasureSpec); if (childrenViews.size() > current) { View child = childrenViews.get(current); child.measure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED)); height = child.getMeasuredHeight(); } heightMeasureSpec = MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY); super.onMeasure(widthMeasureSpec, heightMeasureSpec); } }
调用的方法:创建三个自定义view,添加到view列表中
view1 = UserView(context) viewpager.setObjectForPosition(goodView,0) view2 = UserView(context) viewpager.setObjectForPosition(middleView,1) view3 = UserView(context) viewpager.setObjectForPosition(badView,2)
pageList.add(view1)
pageList.add(view2)
pageList.add(view3)
监听viewpager
viewpager.addOnPageChangeListener(object : ViewPager.OnPageChangeListener { override fun onPageScrollStateChanged(p0: Int) { } override fun onPageScrolled(p0: Int, p1: Float, p2: Int) { } override fun onPageSelected(index: Int) { viewpager.resetHeight(index) //自己的代码实现 } })
设置好后高度问题解决了,因自定义view为了防止tab切换时每次重新加载页面和数据,做了return处理,这里viewpager高度变化后,
NestedScrollView 的高度也许变化,监听是否到底部的事件得重新监听,放到return之前即可
scrollView.setOnScrollChangeListener(NestedScrollView.OnScrollChangeListener { v, scrollX, scrollY, oldScrollX, oldScrollY -> if (scrollY == v.getChildAt(0).measuredHeight - v.measuredHeight) { //到底了 if (isLoadMore) { } else { } } })
if (isLoading) {
return
}