我在popupWindow中创建一个ListView。目前，我的列表视图显示，部件将在现在更新，但如果单击索引更改背景颜色，滚动将其放在页面上，然后滚动回该索引，它不会保留我的更改（这是一个文本更改）。另外，截至目前，另一个问题是“parent.getChildAt（position）.setBackgroundColor（Color.BLUE）;”如果我点击特定索引会导致错误。
以下是包含弹出窗口和列表视图的代码部分
public void bringUpEventsPopover() {
final LayoutInflater layoutInflater = (LayoutInflater)getActivity().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
//inflate the custom popup layout
final View inflatedView = layoutInflater.inflate(R.layout.popup_layout,null,false);
//find the listeview in the popup layout (we will need to construct this still)
final ListView listView = (ListView)inflatedView.findViewById(R.id.commentsListView);
//get device size
/*Display display = getActivity().getWindowManager().getDefaultDisplay();
final Point size = new Point();
display.getSize(size);*/
int width = view.getWidth();
int height = view.getHeight();
//fill the data to the list items
setSimpleList(listView);
//set the height depends on the device size
//popWindow= new PopupWindow(inflatedView, size.x, size.y, true);
popWindow= new PopupWindow(inflatedView, width, height-50, true);
//make it focusable to show the keyboard to enter in 'edittext'
popWindow.setFocusable(true);
popWindow.setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
//show the popup at bottom of the screen and set some margin at bottom
popWindow.showAtLocation(view, Gravity.CENTER, 0, 0);
//make it outside touchable to dismiss the popup window when touched outside the popup area
popWindow.setOutsideTouchable(true);
popWindow.update();
final FrameLayout mainFrame = (FrameLayout) getActivity().findViewById(R.id.frametop);
mainFrame.getForeground().setAlpha(160);
popWindow.setOnDismissListener(new PopupWindow.OnDismissListener() {
@Override
public void onDismiss() {
mainFrame.getForeground().setAlpha(0);
}
});
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id)
{
// selected item
//Event item = (Event)listView.getItemAtPosition(position);
TextView tv = (TextView)view.findViewById(R.id.eventCreator);
parent.getChildAt(position).setBackgroundColor(Color.BLUE);
}
});
}
void setSimpleList(ListView listView){
eventList = new ArrayList<>();
for (int index = 0; index < 6; index++) {
eventList.add(new Event("BT","We gon play sports and stuff","Title","Time is "+index+"pm today","3 Hours","15/30"));
}
for(Event item: eventList)
{
System.out.println(item.getTitle()+"\n"+item.getTime()+"\n"+item.getNumPeople()+"\n");
}
adapter = new ItemAdapter(getActivity(),R.layout.view_event,eventList);
listView.setAdapter(adapter);
}
这是ListView的ItemAdapter类
public class ItemAdapter extends ArrayAdapter<Event> {
// declaring our ArrayList of items
private ArrayList<Event> objects;
/* here we must override the constructor for ArrayAdapter
* the only variable we care about now is ArrayList<Item> objects,
* because it is the list of objects we want to display.
*/
public ItemAdapter(Context context, int textViewResourceId, ArrayList<Event> objects) {
super(context, textViewResourceId, objects);
this.objects = objects;
}
/*
* we are overriding the getView method here - this is what defines how each
* list item will look.
*/
public View getView(int position, View convertView, ViewGroup parent){
LayoutInflater inflater = (LayoutInflater) getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
// assign the view we are converting to a local variable
View v = convertView;
// first check to see if the view is null. if so, we have to inflate it.
// to inflate it basically means to render, or show, the view.
if (v == null) {
v = inflater.inflate(R.layout.view_event, null);
v.setTag(position);
}
else
{
v.getTag();
}
/*
* Recall that the variable position is sent in as an argument to this method.
* The variable simply refers to the position of the current object in the list. (The ArrayAdapter
* iterates through the list we sent it)
*
* Therefore, i refers to the current Item object.
*/
Event i = objects.get(position);
if (i != null) {
// This is how you obtain a reference to the TextViews.
// These TextViews are created in the XML files we defined.
TextView creator = (TextView) v.findViewById(R.id.eventCreator);
TextView title = (TextView) v.findViewById(R.id.eventTitle);
TextView description = (TextView) v.findViewById(R.id.eventDescription);
TextView time = (TextView) v.findViewById(R.id.eventTime);
TextView duration = (TextView) v.findViewById(R.id.eventDuration);
TextView numPeople = (TextView) v.findViewById(R.id.eventAttendance);
// check to see if each individual textview is null.
// if not, assign some text!
if(creator!=null)
{
creator.setText("Creator: "+i.getCreator());
}
if (title != null){
title.setText("Title: "+i.getTitle());
}
if(description!=null)
{
description.setText("Description: "+i.getDescription());
}
if( time != null) {
time.setText("Time: "+i.getTime());
}
if(duration!=null)
{
duration.setText("Duration: "+i.getDuration());
}
if (numPeople != null){
numPeople.setText(i.getNumPeople());
}
}
// the view must be returned to our activity
return v;
}
}
这是每个列表项的布局
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="@+id/eventCreator"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="false"
android:text="Creator: "
android:textAppearance="?android:attr/textAppearanceMedium"
android:layout_margin="5dp" />
<TextView
android:id="@+id/eventTitle"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/eventCreator"
android:text="Title: "
android:textAppearance="?android:attr/textAppearanceMedium"
android:layout_margin="5dp" />
<TextView
android:id="@+id/eventDescription"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/eventTitle"
android:text="Description: "
android:textAppearance="?android:attr/textAppearanceMedium"
android:layout_margin="5dp" />
<TextView
android:id="@+id/eventTime"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/eventDescription"
android:text="Time: "
android:textAppearance="?android:attr/textAppearanceMedium"
android:layout_margin="5dp" />
<TextView
android:id="@+id/eventDuration"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/eventTime"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="Duration: "
android:layout_margin="5dp" />
<TextView
android:id="@+id/eventAttendance"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/eventDuration"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="15/30 Going"
android:layout_margin="5dp" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/eventAttendance"
android:textAppearance="?android:attr/textAppearanceMedium"
android:layout_margin="20dp"
android:text="I'm Going!"
android:layout_centerHorizontal="true"
android:focusable="false"
android:clickable="false"/>
</RelativeLayout>
答案 0 :(得分：1)
两个想法。 1）也许考虑一个容器为您的事件/项目，以便您可以给他们动态ID，然后使用它们来设置背景颜色。当它滚动/关闭屏幕时，你可能会更幸运地保存状态。 2）我对此并不是百分之百确定，所以不要把它当作福音，但我认为当你将视图中的列表视图滚动时，适配器可能会混淆子结构中的索引变量。有没有其他方法可以访问该列表视图的子节点？对不起，我对这个问题没有一个好的答案，只是一个让你追逐的想法。祝你好运！
答案 1 :(得分：0)
我自己想通了。因此阵列适配器在设置时有几个部分。
// first check to see if the view is null. if so, we have to inflate it.
// to inflate it basically means to render, or show, the view.
if (v == null) {
/* This is where you initialize new rows, by:
* - Inflating the layout,
* - Instantiating the ViewHolder,
* - And defining any characteristics that are consistent for every row */
v = inflater.inflate(R.layout.view_event, null);
v.setTag(position);
}
else
{
/* Fetch data already in the row layout,
* primarily you only use this to get a copy of the ViewHolder */
v.getTag();
}
/* Set the data that changes in each row, like `title` and `size`
* This is where you give rows there unique values. */
所以我在我的事件类中设置了一个新变量来保存＆＃34; isSelected＆＃34;字段，我的＆＃34; onItemClickListener＆＃34;设置，然后通知ArrayAdapter数据更改。 在数组适配器中，我只是检查了Event.isSelected（）var并相应地加载了背景。
改变背景的myArrayAdapter：
if(objects.get(position).isSelected())
{
v.setBackgroundColor(Color.CYAN);
}
else
{
v.setBackgroundColor(Color.WHITE);
}
myItemClickListener：
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id)
{
// selected item
adapter.objects.get(position).setSelected(true);
adapter.notifyDataSetChanged();
}
});