问题：今天在写一个NestedScrollView嵌套TabLayout+ViewPager+Fragment页面的时候，写完只有一个Tablayout，没有ViewPager，当时害怕极了~
度了一下，说是在NestedScrollView布局中添加参数 android:fillViewport="true"可以解决，赶紧试了下，结果并没有解决我的问题！
有一位网友是这样描述的：
先前在低于Android 9 以下版本开发的时候 在NestedScrollView 控件属性中加入android:fillViewport=“true” 充满布局属性还起作用，之后就无效了。
可是我试了下9以下的好像也是不行的，这问题不用纠结，就算是9以下可以那也得适配啊，go on
最终还是走了自定义
自定义ViewPager，重写onMeasure，通过在VP中记录每个Fragment创建完成后对应的View，然后根据对应Fragment的View的高度来重置ViewPager的高度。代码如下：
/**
* Des:
* Created by kele on 2020/9/17.
* E-mail:984127585@qq.com
*/
public class AutoHeightViewPager extends ViewPager {
private int current;
private int height = 0;
/**
* 保存position与对应的View
*/
private HashMap<Integer, View> mChildrenViews = new LinkedHashMap<Integer, View>();
private boolean scrollble = true;
public AutoHeightViewPager(Context context) {
super(context);
}
public AutoHeightViewPager(Context context, AttributeSet attrs) {
super(context, attrs);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
if (mChildrenViews.size() > current) {
View child = mChildrenViews.get(current);
child.measure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
height = child.getMeasuredHeight();
}
heightMeasureSpec = MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY);
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
public void resetHeight(int current) {
this.current = current;
if (mChildrenViews.size() > current) {
ViewGroup.LayoutParams layoutParams = (ViewGroup.LayoutParams) getLayoutParams();
if (layoutParams == null) {
layoutParams = new ViewGroup.LayoutParams(ViewGroup.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) {
mChildrenViews.put(position, view);
}
@Override
public boolean onTouchEvent(MotionEvent ev) {
if (!scrollble) {
return true;
}
return super.onTouchEvent(ev);
}
public boolean isScrollble() {
return scrollble;
}
public void setScrollble(boolean scrollble) {
this.scrollble = scrollble;
}
}
对应的Fragment代码如下：
/**
* Des:
* Created by kele on 2020/9/17.
* E-mail:984127585@qq.com
*/
public class DetailFragment extends BaseFragment {
private int mPosition;
private AutoHeightViewPager mVP;
public DetailFragment (AutoHeightViewPager vp, List<ListBean> list, int position) {
super(true);
mVP = vp;
mList = list;
mPosition = position;
}
@Override
protected IBaseP createPresenter() {
return null;
}
@Override
protected int getContentViewID() {
return R.layout.fragment_huati_detail;
}
@Override
protected void initViews(View v) {
mVP.setObjectForPosition(v, mPosition);
}
@Override
protected void initData() {
}
}
对应Activity中的操作代码如下：
vp.resetHeight(0);
//添加viewpager 切换监听
stl.setOnTabSelectListener(new OnTabSelectListener() {
@Override
public void onTabSelect(int position) {
vp.resetHeight(position);
}
@Override
public void onTabReselect(int position) {
}
});
vp.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
@Override
public void onPageSelected(int position) {
vp.resetHeight(position);
}
@Override
public void onPageScrollStateChanged(int state) {
}
});
