我有一个android布局，其中有一个带有许多元素的scrollView。在scrollView的底部，我有一个listView，然后由适配器填充。
我遇到的问题是，android是排除listView从scrollView作为scrollView已经有一个可滚动的功能。我希望listView和内容一样长，并且主滚动视图是可滚动的。
我怎样才能实现这种行为呢?
这是我的主要布局:
<ScrollView
android:id="@+id/scrollView1"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="2"
android:fillViewport="true"
android:gravity="top" >
<LinearLayout
android:id="@+id/foodItemActvity_linearLayout_fragments"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
</LinearLayout>
</ScrollView>
然后，我以编程方式将我的组件添加到linearlayour的id: foodItemActvity_linearLayout_fragments。下面是加载到线性布局中的一个视图。就是这个给我的卷轴带来了麻烦。
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<TextView
android:id="@+id/fragment_dds_review_textView_label"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Reviews:"
android:textAppearance="?android:attr/textAppearanceMedium" />
<ListView
android:id="@+id/fragment_dds_review_listView"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</ListView>
</LinearLayout>
我的适配器然后填充这个列表视图。
当我点击主scrollView时，这是一个来自android层级查看器的图像:
如您所见，它排除了评论列表视图。
我应该能够向下滚动页面，看到8个评论，但它只显示了这3个，我可以滚动评论所在的一小部分。我想要一个全局页面滚动
找到了一个解决方案scrollview -> viewpager -> FragmentPagerAdapter -> fragment ->动态listview，但我不是作者。
public class CustomPager extends ViewPager {
private View mCurrentView;
public CustomPager(Context context) {
super(context);
}
public CustomPager(Context context, AttributeSet attrs) {
super(context, attrs);
}
@Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
if (mCurrentView == null) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
return;
}
int height = 0;
mCurrentView.measure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
int h = mCurrentView.getMeasuredHeight();
if (h > height) height = h;
heightMeasureSpec = MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY);
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
public void measureCurrentView(View currentView) {
mCurrentView = currentView;
this.post(new Runnable() {
@Override
public void run() {
requestLayout();
}
});
}
public int measureFragment(View view) {
if (view == null)
return 0;
view.measure(0, 0);
return view.getMeasuredHeight();
}
}
public class MyPagerAdapter extends FragmentPagerAdapter {
private List<Fragment> fragments;
private int mCurrentPosition = -1;
public MyPagerAdapter(FragmentManager fm) {
super(fm);//or u can set them separately, but dont forget to call notifyDataSetChanged()
this.fragments = new ArrayList<Fragment>();
fragments.add(new FirstFragment());
fragments.add(new SecondFragment());
fragments.add(new ThirdFragment());
fragments.add(new FourthFragment());
}
@Override
public void setPrimaryItem(ViewGroup container, int position, Object object) {
super.setPrimaryItem(container, position, object);
if (position != mCurrentPosition) {
Fragment fragment = (Fragment) object;
CustomPager pager = (CustomPager) container;
if (fragment != null && fragment.getView() != null) {
mCurrentPosition = position;
pager.measureCurrentView(fragment.getView());
}
}
}
@Override
public Fragment getItem(int position) {
return fragments.get(position);
}
@Override
public int getCount() {
return fragments.size();
}
}
片段布局可以是任何东西
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:orientation="vertical"
android:layout_height="match_parent" tools:context="nevet.me.wcviewpagersample.FirstFragment">
<ListView
android:id="@+id/lv1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#991199"/>
</LinearLayout>
然后在某个地方
lv = (ListView) view.findViewById(R.id.lv1);
lv.setAdapter(arrayAdapter);
setListViewHeightBasedOnChildren(lv);
}
public static void setListViewHeightBasedOnChildren(ListView listView) {
ListAdapter listAdapter = listView.getAdapter();
if (listAdapter == null)
return;
int desiredWidth = View.MeasureSpec.makeMeasureSpec(listView.getWidth(),
View.MeasureSpec.UNSPECIFIED);
int totalHeight = 0;
View view = null;
for (int i = 0; i < listAdapter.getCount(); i++) {
view = listAdapter.getView(i, view, listView);
if (i == 0)
view.setLayoutParams(new ViewGroup.LayoutParams(desiredWidth,
LinearLayout.LayoutParams.WRAP_CONTENT));
view.measure(desiredWidth, View.MeasureSpec.UNSPECIFIED);
totalHeight += view.getMeasuredHeight();
}
ViewGroup.LayoutParams params = listView.getLayoutParams();
params.height = totalHeight
+ (listView.getDividerHeight() * (listAdapter.getCount() - 1));
listView.setLayoutParams(params);
listView.requestLayout();
}
找到了一个解决方案scrollview -> viewpager -> FragmentPagerAdapter -> fragment ->动态listview，但我不是作者。
public class CustomPager extends ViewPager {
private View mCurrentView;
public CustomPager(Context context) {
super(context);
}
public CustomPager(Context context, AttributeSet attrs) {
super(context, attrs);
}
@Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
if (mCurrentView == null) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
return;
}
int height = 0;
mCurrentView.measure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
int h = mCurrentView.getMeasuredHeight();
if (h > height) height = h;
heightMeasureSpec = MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY);
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
public void measureCurrentView(View currentView) {
mCurrentView = currentView;
this.post(new Runnable() {
@Override
public void run() {
requestLayout();
}
});
}
public int measureFragment(View view) {
if (view == null)
return 0;
view.measure(0, 0);
return view.getMeasuredHeight();
}
}
public class MyPagerAdapter extends FragmentPagerAdapter {
private List<Fragment> fragments;
private int mCurrentPosition = -1;
public MyPagerAdapter(FragmentManager fm) {
super(fm);//or u can set them separately, but dont forget to call notifyDataSetChanged()
this.fragments = new ArrayList<Fragment>();
fragments.add(new FirstFragment());
fragments.add(new SecondFragment());
fragments.add(new ThirdFragment());
fragments.add(new FourthFragment());
}
@Override
public void setPrimaryItem(ViewGroup container, int position, Object object) {
super.setPrimaryItem(container, position, object);
if (position != mCurrentPosition) {
Fragment fragment = (Fragment) object;
CustomPager pager = (CustomPager) container;
if (fragment != null && fragment.getView() != null) {
mCurrentPosition = position;
pager.measureCurrentView(fragment.getView());
}
}
}
@Override
public Fragment getItem(int position) {
return fragments.get(position);
}
@Override
public int getCount() {
return fragments.size();
}
}
片段布局可以是任何东西
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:orientation="vertical"
android:layout_height="match_parent" tools:context="nevet.me.wcviewpagersample.FirstFragment">
<ListView
android:id="@+id/lv1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#991199"/>
</LinearLayout>
然后在某个地方
lv = (ListView) view.findViewById(R.id.lv1);
lv.setAdapter(arrayAdapter);
setListViewHeightBasedOnChildren(lv);
}
public static void setListViewHeightBasedOnChildren(ListView listView) {
ListAdapter listAdapter = listView.getAdapter();
if (listAdapter == null)
return;
int desiredWidth = View.MeasureSpec.makeMeasureSpec(listView.getWidth(),
View.MeasureSpec.UNSPECIFIED);
int totalHeight = 0;
View view = null;
for (int i = 0; i < listAdapter.getCount(); i++) {
view = listAdapter.getView(i, view, listView);
if (i == 0)
view.setLayoutParams(new ViewGroup.LayoutParams(desiredWidth,
LinearLayout.LayoutParams.WRAP_CONTENT));
view.measure(desiredWidth, View.MeasureSpec.UNSPECIFIED);
totalHeight += view.getMeasuredHeight();
}
ViewGroup.LayoutParams params = listView.getLayoutParams();
params.height = totalHeight
+ (listView.getDividerHeight() * (listAdapter.getCount() - 1));
listView.setLayoutParams(params);
listView.requestLayout();
}
如果出于某种原因你不想使用addHeaderView和addFooterView，例如当你有几个列表时，一个好主意是重用ListAdapter来填充一个简单的线性布局，这样就没有滚动功能了。
如果你已经从ListFragment中获得了一个完整的片段，并且想用简单的线性布局将其转换为一个类似的片段，而不需要滚动(例如，将它放在ScrollView中)，你可以像这样实现一个适配器片段:
// converts listFragment to linearLayout (no scrolling)
// please call init() after fragment is inflated to set listFragment to convert
public class ListAsArrayFragment extends Fragment {
public ListAsArrayFragment() {}
private ListFragment mListFragment;
private LinearLayout mRootView;
// please call me!
public void init(Activity activity, ListFragment listFragment){
mListFragment = listFragment;
mListFragment.onAttach(activity);
mListFragment.getListAdapter().registerDataSetObserver(new DataSetObserver() {
@Override
public void onChanged() {
super.onChanged();
refreshView();
}
});
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
// create an empty vertical LinearLayout as the root view of this fragment
mRootView = new LinearLayout(getActivity());
mRootView.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
mRootView.setOrientation(LinearLayout.VERTICAL);
return mRootView;
}
// reusing views for performance
// todo: support for more than one view type
ArrayList<View> mViewsToReuse = new ArrayList<>();
ArrayList<View> mCurrentViews = new ArrayList<>();
// re-add views to linearLayout
void refreshView(){
// remove old views from linearLayout and move them to mViewsToReuse
mRootView.removeAllViews();
mViewsToReuse.addAll(mCurrentViews);
mCurrentViews.clear();
// create new views
for(int i=0; i<mListFragment.getListAdapter().getCount(); ++i){
View viewToReuse = null;
if(!mViewsToReuse.isEmpty()){
viewToReuse = mViewsToReuse.get(mViewsToReuse.size()-1);
mViewsToReuse.remove(mViewsToReuse.size()-1);
}
final View view = mListFragment.getListAdapter().getView(i, viewToReuse, mRootView);
ViewGroup.LayoutParams oldParams = view.getLayoutParams();
view.setLayoutParams(new LinearLayout.LayoutParams(oldParams.width, oldParams.height));
final int finalI = i;
// pass click events to listFragment
view.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mListFragment.onListItemClick(null, view, finalI, finalI);
}
});
mRootView.addView(view);
mCurrentViews.add(view);
}
}
你也可以根据你的需要转发onCreate, onPause, onResume等到原始片段或尝试继承而不是组合(但覆盖某些方法，因此原始片段实际上没有附加到布局层次结构);但是我想尽可能地分离原始片段，因为我们只需要提取它的ListAdapter。如果你在onAttach中调用原始片段的setListAdapter，这可能就足够了。
下面是如何使用ListAsArrayFragment包含OriginalListFragment而不滚动。在父活动的onCreate中:
ListAsArrayFragment fragment = (ListAsArrayFragment) getFragmentManager().findFragmentById(R.id.someFragmentId);
OriginalListFragment originalFragment = new OriginalListFragment();
fragment.init(this, originalFragment);
// now access originalFragment.getListAdapter() to modify list entries
// and remember to call notifyDatasetChanged()
使用这个ListView对我有用
package net.londatiga.android.widget;
import android.util.AttributeSet;
import android.view.ViewGroup;
import android.widget.ListView;
import android.content.Context;
public class ExpandableHeightListView extends ListView
{
boolean expanded = false;
public ExpandableHeightListView(Context context)
{
super(context);
}
public ExpandableHeightListView(Context context, AttributeSet attrs)
{
super(context, attrs);
}
public ExpandableHeightListView(Context context, AttributeSet attrs,
int defStyle)
{
super(context, attrs, defStyle);
}
public boolean isExpanded()
{
return expanded;
}
@Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
// HACK! TAKE THAT ANDROID!
if (isExpanded())
{
// Calculate entire height by providing a very large height hint.
// But do not use the highest 2 bits of this integer; those are
// reserved for the MeasureSpec mode.
int expandSpec = MeasureSpec.makeMeasureSpec(
Integer.MAX_VALUE >> 2, MeasureSpec.AT_MOST);
super.onMeasure(widthMeasureSpec, expandSpec);
ViewGroup.LayoutParams params = getLayoutParams();
params.height = getMeasuredHeight();
}
else
{
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
}
public void setExpanded(boolean expanded)
{
this.expanded = expanded;
}
}
在XML中
<com.pakagename.ExpandableHeightListView
android:id="@+id/expandableHeightListView"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</com.Example.ExpandableHeightListView>
在MainActivity中
ExpandableHeightListView listView = new ExpandableHeightListView(this);
listview=(ExpandableHeightListView)findViewById(R.id.expandableHeightListView);
listView.setAdapter(adapter); //set your adaper
listView.setExpanded(true);
参考这篇文章了解更多信息，也知道如何保持网格视图在滚动视图
