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
我有一个类似于原始海报的问题——如何让列表视图在滚动视图中滚动——这个答案解决了我的问题。
禁止滚动包含在ScrollView中的ListView
我没有调用新的片段到现有的布局或类似的东西,就像OP所做的那样,所以我的代码看起来像这样:
<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" >
<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/my_listView"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</ListView>
</LinearLayout>
</ScrollView>
基本上我要做的是在我调用它之前检查listview的长度,当我调用它时,我把它变成那个长度。在你的java类中使用这个函数:
public static void justifyListViewHeightBasedOnChildren (ListView listView) {
ListAdapter adapter = listView.getAdapter();
if (adapter == null) {
return;
}
ViewGroup vg = listView;
int totalHeight = 0;
for (int i = 0; i < adapter.getCount(); i++) {
View listItem = adapter.getView(i, null, vg);
listItem.measure(0, 0);
totalHeight += listItem.getMeasuredHeight();
}
ViewGroup.LayoutParams par = listView.getLayoutParams();
par.height = totalHeight + (listView.getDividerHeight() * (adapter.getCount() - 1));
listView.setLayoutParams(par);
listView.requestLayout();
}
然后像这样调用函数:
justifyListViewHeightBasedOnChildren(listView);
结果是一个没有滚动条的列表视图,显示整个列表视图的长度,它与滚动视图的滚动条一起滚动。
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());
}
}
}