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
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
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()
I'll leave it here in case anyone will face the same issue. I had to put a ListView inside a ScrollView. ListView with header was not an option by a number of reasons. Neither was an option to use LinearLayout instead of ListView. So I followed the accepted solution, but it didn't work because items in the list had complex layout with multiple rows and each listview item was of variable height. Height was measured not properly. The solution was to measure each item inside ListView Adapter's getView() method.
@Override
public View getView(int position, View view, ViewGroup parent) {
ViewHolder holder;
if (view == null) {
. . .
view.setTag(holder);
} else holder = (ViewHolder)view.getTag();
. . .
// measure ListView item (to solve 'ListView inside ScrollView' problem)
view.measure(View.MeasureSpec.makeMeasureSpec(
View.MeasureSpec.UNSPECIFIED, View.MeasureSpec.UNSPECIFIED),
View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED));
return view;
}
这对我有用(link1, link2):
You Create Custom ListView Which is non Scrollable
public class NonScrollListView extends ListView {
public NonScrollListView(Context context) {
super(context);
}
public NonScrollListView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public NonScrollListView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
@Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int heightMeasureSpec_custom = View.MeasureSpec.makeMeasureSpec(
Integer.MAX_VALUE >> 2, View.MeasureSpec.AT_MOST);
super.onMeasure(widthMeasureSpec, heightMeasureSpec_custom);
ViewGroup.LayoutParams params = getLayoutParams();
params.height = getMeasuredHeight();
}
}
In Your Layout File
<ScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:fillViewport="true">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<!-- com.Example Changed with your Package name -->
<com.thedeveloperworldisyours.view.NonScrollListView
android:id="@+id/lv_nonscroll_list"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</com.thedeveloperworldisyours.view.NonScrollListView>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_below="@+id/lv_nonscroll_list" >
<!-- Your another layout in scroll view -->
</RelativeLayout>
</RelativeLayout>
</ScrollView>
Create a object of your customListview instead of ListView like :
NonScrollListView non_scroll_list = (NonScrollListView) findViewById(R.id.lv_nonscroll_list);
如果你只是在代码中实现了一个ListView,这段代码将解决你的问题。
如果你使用RelativeLayout作为ListView子视图,那么这段代码将返回一个NullPointerException。测量(0,0);,因为相对布局。解决办法是把Relativelayout放在LinearLayout里面,它会工作得很好。
public static void setListViewHeightBasedOnChildren(ListView listView) {
ListAdapter listAdapter = listView.getAdapter();
if (listAdapter == null) {
// pre-condition
return;
}
int totalHeight = 0;
for (int i = 0; i < listAdapter.getCount(); i++) {
View listItem = listAdapter.getView(i, null, listView);
listItem.measure(0, 0);
totalHeight += listItem.getMeasuredHeight();
}
ViewGroup.LayoutParams params = listView.getLayoutParams();
params.height = totalHeight + (listView.getDividerHeight() * (listAdapter.getCount() - 1));
listView.setLayoutParams(params);
listView.requestLayout();
}