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。虽然有些bug，但至少还能用
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();
}
正如其他人已经提到的，不要在ScrollView中使用ListView。
为了解决问题，你可以使用LinearLayout，但仍然要保持整洁-用适配器填充你的LinearLayout，就像你用ListView做的一样
您可以使用这个类作为支持适配器的线性布局替代品
import android.content.Context;
import android.database.DataSetObserver;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.LinearLayout;
public class AdaptableLinearLayout extends LinearLayout {
private BaseAdapter mAdapter;
private int mItemCount = 0;
private boolean mDisableChildrenWhenDisabled = false;
private int mWidthMeasureSpec;
private int mHeightMeasureSpec;
public AdaptableLinearLayout(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
}
public BaseAdapter getAdapter() {
return mAdapter;
}
public void setAdapter(BaseAdapter adapter) {
mAdapter = adapter;
adapter.registerDataSetObserver(new DataSetObserver() {
@Override
public void onChanged() {
updateLayout();
super.onChanged();
}
@Override
public void onInvalidated() {
updateLayout();
super.onInvalidated();
}
});
updateLayout();
}
private void updateLayout() {
mItemCount = mAdapter.getCount();
requestLayout();
invalidate();
}
/**
* set size for the current View
*/
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
mWidthMeasureSpec = widthMeasureSpec;
mHeightMeasureSpec = heightMeasureSpec;
removeAllViewsInLayout();
for (int i = 0; i < mItemCount; i++) {
makeAndAddView(i);
}
}
private View makeAndAddView(int position) {
View child;
// Nothing found in the recycler -- ask the adapter for a view
child = mAdapter.getView(position, null, this);
// Position the view
setUpChild(child, position);
return child;
}
private void setUpChild(View child, int position) {
ViewGroup.LayoutParams lp = child.getLayoutParams();
if (lp == null) {
lp = generateDefaultLayoutParams();
}
addViewInLayout(child, position, lp);
// Get measure specs
int childHeightSpec = ViewGroup.getChildMeasureSpec(mHeightMeasureSpec, getPaddingTop() + getPaddingBottom(), lp.height);
int childWidthSpec = ViewGroup.getChildMeasureSpec(mWidthMeasureSpec, getPaddingLeft() + getPaddingRight(), lp.width);
// Measure child
child.measure(childWidthSpec, childHeightSpec);
int childLeft;
int childRight;
// Position vertically based on gravity setting
int childTop = getPaddingTop() + ((getMeasuredHeight() - getPaddingBottom() - getPaddingTop() - child.getMeasuredHeight()) / 2);
int childBottom = childTop + child.getMeasuredHeight();
int width = child.getMeasuredWidth();
childLeft = 0;
childRight = childLeft + width;
child.layout(childLeft, childTop, childRight, childBottom);
if (mDisableChildrenWhenDisabled) {
child.setEnabled(isEnabled());
}
}
}
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;
}
