android - 覆盖默认的 expandablelistview 扩展行为

Question

如何手动展开和折叠可展开 ListView ？我知道 expandGroup()，但不确定在哪里设置 onClickListener()，因为这段代码的一半位于单独的库项目中。

ExpandableDeliveryList

package com.goosesys.dta_pta_test;
[imports removed to save space]

public class ExpandableDeliveryList<T> extends ExpandableListActivity {

private ArrayList<GooseDeliveryItem> parentItems = new ArrayList<GooseDeliveryItem>();
private ArrayList<DeliverySiteExtras> childItems = new ArrayList<DeliverySiteExtras>();

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    // CREATE THE EXPANDABLE LIST AND SET PROPERTIES //
    final ExpandableListView expandList = getExpandableListView();
    expandList.setDividerHeight(0);
    expandList.setGroupIndicator(null);
    expandList.setClickable(false); 

    // LIST OF PARENTS //
    setGroupParents();

    // CHILDREN //
    setChildData();

    // CREATE ADAPTER //
    GooseExpandableArrayAdapter<?> adapter = new GooseExpandableArrayAdapter<Object>(
            R.layout.goose_delivery_item,
            R.layout.goose_delivery_item_child,
            parentItems, 
            childItems);
    adapter.setInflater((LayoutInflater)getSystemService(Context.LAYOUT_INFLATER_SERVICE), this);       
    expandList.setAdapter(adapter);
    expandList.setOnChildClickListener(this);   
}

@Override
public boolean onOptionsItemSelected(MenuItem item)
{
    switch(item.getItemId())
    {
        case android.R.id.home:
        {
            Intent intent = new Intent(this, Main.class);
            intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_SINGLE_TOP);
            startActivity(intent);
            return true;
        }

        default:
        {
            return super.onOptionsItemSelected(item);
        }
    }
}

public void setGroupParents()
{
    DatabaseHelper dbHelper = new DatabaseHelper(this);
    List<DeliverySite> sites = new ArrayList<DeliverySite>();       
    sites = dbHelper.getAllSites();

    GooseDeliveryItem[] deliveries = new GooseDeliveryItem[sites.size()];

    for(int i=0; i<sites.size(); i++)
    {
        Delivery del = new Delivery();

        try
        {
            del = dbHelper.getDeliveryByJobNo(sites.get(i).id);
        }
        catch(Exception e)
        {
            e.printStackTrace();
        }

        final GooseDeliveryItem gdi;

        if((Double.isNaN(sites.get(i).lat)) || (Double.isNaN(sites.get(i).lng)))
        {
            gdi = new GooseDeliveryItem(sites.get(i).id, sites.get(i).company);
        }
        else
        {
            gdi = new GooseDeliveryItem(sites.get(i).id, sites.get(i).company, sites.get(i).lat, sites.get(i).lng);
        }

        if(del.getReportedFully() == 1)
        {
            gdi.isReportedFully = true;
        }

        deliveries[i] = gdi;
    }

    // FINALLY ADD THESE ITEMS TO THE PARENT ITEMS LIST ARRAY //
    for(GooseDeliveryItem g : deliveries)
        parentItems.add(g);
}

public void setChildData()
{       
    //DatabaseHelper dbHelper = new DatabaseHelper(this);
    ArrayList<DeliverySiteExtras> extras = new ArrayList<DeliverySiteExtras>();

    for(int i=0; i<parentItems.size(); i++)
    {
        DeliverySiteExtras dse = new DeliverySiteExtras();
        extras.add(dse);
    }

    childItems = extras;
}
}

数组适配器

package com.goosesys.gooselib.Views;

[imports removed to save space]

public class GooseExpandableArrayAdapter<Object> extends BaseExpandableListAdapter 
{
private Activity activity;
private ArrayList<DeliverySiteExtras> childItems;
private LayoutInflater inflater;
ArrayList<GooseDeliveryItem> parentItems;
private DeliverySiteExtras child;
private int layoutId;
private int childLayoutId;

public GooseExpandableArrayAdapter(int layoutId, int childLayoutId, ArrayList<GooseDeliveryItem> parents, ArrayList<DeliverySiteExtras> children)
{
    this.layoutId = layoutId;
    this.childLayoutId = childLayoutId;
    this.parentItems = (ArrayList<GooseDeliveryItem>) parents;
    this.childItems = (ArrayList<DeliverySiteExtras>)children;
}

public GooseExpandableArrayAdapter(ArrayList<GooseDeliveryItem> parents, ArrayList<DeliverySiteExtras> children, int layoutId)
{
    this.parentItems = parents;
    this.childItems = children;
    this.layoutId = layoutId;
}

public void setInflater(LayoutInflater inflater, Activity activity)
{
    this.inflater = inflater;
    this.activity = activity;
}   

@Override
public Object getChild(int arg0, int arg1) 
{
    return null;
}

@Override
public long getChildId(int arg0, int arg1) 
{
    return 0;
}

/*
 * Child view get method
 * Utilise this to edit view properties at run time
 */
@Override
public View getChildView(int groupPosition, int childPosition, boolean isLastChild, View convertView, ViewGroup parent) 
{
    child = childItems.get(groupPosition);

    if(convertView == null)
    {
        convertView = inflater.inflate(this.childLayoutId, null);           
    }       

    // GET ALL THE OBJECT VIEWS AND SET THEM HERE //
    setGeoLocation(groupPosition, convertView);

    convertView.setOnClickListener(new View.OnClickListener() 
    {       
        @Override
        public void onClick(View arg0) 
        {
        }
    });

    return convertView;
}

@Override
public void onGroupCollapsed(int groupPosition)
{
    super.onGroupCollapsed(groupPosition);
}

@Override
public void onGroupExpanded(int groupPosition)
{
    super.onGroupExpanded(groupPosition);
}

@Override
public int getChildrenCount(int groupPosition) 
{
    return 1; //childItems.get(groupPosition);
}

@Override
public Object getGroup(int groupPosition) 
{
    return null;
}

@Override
public int getGroupCount() 
{
    return parentItems.size();
}

@Override
public long getGroupId(int arg0) 
{
    return 0;
}

/*
 * Parent View Object get method
 * Utilise this to edit view properties at run time.
 */
@Override
public View getGroupView(final int groupPosition, boolean isExpanded, View convertView, ViewGroup parent) 
{   
    if(convertView == null)
    {
        convertView = inflater.inflate(this.layoutId, null);
    }

    // GET ALL OBJECT VIEWS AND SET THEM HERE -- PARENT VIEW //     
    TextView name = (TextView)convertView.findViewById(R.id.customerName);
    name.setText(parentItems.get(groupPosition).customerText);  

    ImageView go = (ImageView)convertView.findViewById(R.id.moreDetails);
    go.setOnClickListener(new View.OnClickListener() 
    {
        @Override
        public void onClick(View v) 
        {           
            Intent i = new Intent(activity, DeliveryJobActivity.class);
            i.putExtra("obj", parentItems.get(groupPosition));
            activity.startActivity(i);
        }
    });

    return convertView;
}

@Override
public boolean hasStableIds() 
{
    return false;
}

@Override
public boolean isChildSelectable(int arg0, int arg1) 
{
    return false;
}

private void setGeoLocation(final int groupPosition, View parent)
{
    GeoLocation geoLocation = new GeoLocation(activity);
    final double lat = geoLocation.getLatitude();
    final double lng = geoLocation.getLongitude();

    // GET OUR START LOCATION //
    Location startLocation = new Location("Start");
    startLocation.setLatitude(lat);
    startLocation.setLongitude(lng);

    // GET OUR DESTINATION //
    Location destination = new Location("End");
    destination.setLatitude(((GooseDeliveryItem)parentItems.get(groupPosition)).latitude);
    destination.setLongitude(((GooseDeliveryItem)parentItems.get(groupPosition)).longitude);        

    double distanceValue = startLocation.distanceTo(destination);

    TextView tv = (TextView)parent.findViewById(R.id.extraHeader);
    tv.setText(parentItems.get(groupPosition).customerText + " information:");

    TextView ds = (TextView)parent.findViewById(R.id.deliveryDistance);
    ds.setText("Distance (from location): " + String.valueOf(Math.ceil(distanceValue * GooseConsts.METERS_TO_A_MILE)) + " Mi (approx)");

    ImageView img = (ImageView)parent.findViewById(R.id.directionsImage);
    img.setOnClickListener(new View.OnClickListener() {         
        @Override
        public void onClick(View arg0) {
            // invoke google maps with lat / lng position
            Intent navigation = new Intent(Intent.ACTION_VIEW, Uri.parse(
                    "http://maps.google.com/maps?saddr="
                    + (lat) + "," + (lng)
                    + "&daddr="
                    + ((GooseDeliveryItem)parentItems.get(groupPosition)).latitude + ","
                    + ((GooseDeliveryItem)parentItems.get(groupPosition)).longitude                             
                    ));
            activity.startActivity(navigation);                 
        }
    });
}
}

理想情况下，我的老板希望有一个“+”按钮，单击该按钮可手动展开 ListView 。而不是单击 View 上的任何位置并自动执行。这可能吗？此外，设置 setClickable(false) 似乎没有效果。因为单击任何列表项时它仍会展开。我是否也遗漏了什么？

干杯。

Answer 1

您可以添加一个 ExpandableListView 组点击监听器(“ExpandableListView::setOnGroupClickListener”)来监控和抑制 ListView 组的点击事件。使用您的代码示例，这将在您创建 ExpandableListView 后在您的“ExpandableDeliveryList”模块中完成。

然后在您的“+”(和“-”)按钮单击处理程序中，您可以添加逻辑以使用“ExpandableListView::expandGroup()”和“ExpandableListView::collapseGroup”展开/折叠部分或全部 ListView 组()”方法。

您不需要从重写的“isChildSelectable()”方法返回“false”，因为这对您试图完成的事情没有影响(并且会阻止任何人单击/选择 ListView 中的子项)。

代码示例如下:

// CREATE THE EXPANDABLE LIST AND SET PROPERTIES //
final ExpandableListView expandList = getExpandableListView();      
//...

expandList.setOnGroupClickListener(new android.widget.ExpandableListView.OnGroupClickListener() {

    @Override
    public boolean onGroupClick(    ExpandableListView  parent,
                                    View                view,
                                    int                 groupPosition,
                                    long                id) {

        //  some code...

        //  return "true" to consume the event (and prevent the Group from expanding/collapsing) / "false" to allow the Group to expand/collapse normally
        return true;
    }
});

手动展开和折叠 ListView 组:

//  enumerate thru the ExpandableListView Groups
//  [in this code example, a single index is used...]
int groupPosition = 0;

//  expand the ListView Group/s
if (m_expandableListView.isGroupExpanded(groupPosition) == false) {

    //  API Level 14+ allows you to animate the Group expansion...
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.ICE_CREAM_SANDWICH) {
        m_expandableListView.expandGroup(groupPosition, true);
    }

    //  else just expand the Group without animation
    else {
        m_expandableListView.expandGroup(groupPosition);
    }               
}

//  collapse the ListView Group/s
else {
    m_expandableListView.collapseGroup(groupPosition);          
}

希望这对您有所帮助。