android ExpandableListView詳解

時間 2019-11-07

標籤 android expandablelistview 詳解欄目 Android 简体版

原文原文鏈接

ExpandableListView是android中能夠實現下拉list的一個控件，是一個垂直滾動的心事兩個級別列表項手風琴試圖，列表項是來自ExpandableListViewaAdapter，組能夠單獨展開。java

重要方法：android

expandGroup (int groupPos) ;//在分組列表視圖中 展開一組，
setSelectedGroup (int groupPosition) ;//設置選擇指定的組。

setSelectedChild (int groupPosition, int childPosition, boolean shouldExpandGroup);//設置選擇指定的子項。

getPackedPositionGroup (long packedPosition);//返回所選擇的組

getPackedPositionForChild (int groupPosition, int childPosition) ;//返回所選擇的子項

getPackedPositionType (long packedPosition);//返回所選擇項的類型（Child,Group）

isGroupExpanded (int groupPosition);//判斷此組是否展開

expandableListView.setDivider();這個是設定每一個Group之間的分割線。web

expandableListView.setGroupIndicator();這個是設定每一個Group以前的那個圖標。
app

expandableListView.collapseGroup(int group); 將第group組收起ide

ExpandableListAdapter佈局

一個接口，將基礎數據連接到一個ExpandableListView。此接口的實施將提供訪問Child的數據（由組分類），並實例化的Child和Group。this

1.重要方法spa

　　　　getChildId (int groupPosition, int childPosition) 獲取與在給定組給予孩子相關的數據。code

　　　　getChildrenCount (int groupPosition) 返回在指定Group的Child數目。orm

案例：

首先定義個一個佈局文件expandablelistview.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >
     <ExpandableListView 
        android:id ="@+id/expandableListView"   
	    android:layout_width ="fill_parent"   
	    android:layout_height ="wrap_content"   
        >
     </ExpandableListView>
</LinearLayout>

package com.test;

import java.util.ArrayList;
import java.util.List;

import javax.security.auth.PrivateCredentialPermission;

import android.app.Activity;
import android.os.Bundle;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.widget.AbsListView;
import android.widget.BaseExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.TextView;

public class ExpandableListViewDemo extends Activity {
    /** Called when the activity is first created. */
	
	//定義兩個List用來控制Group和Child中的String;
	
	private  List<String>  groupArray;//組列表
	private  List<List<String>> childArray;//子列表
	private  ExpandableListView  expandableListView_one;
	
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
//        requestWindowFeature(Window.FEATURE_NO_TITLE);  //設置爲無標題  
        setContentView(R.layout.expandablelistview);
        expandableListView_one =(ExpandableListView)findViewById(R.id.expandableListView);
        groupArray =new ArrayList<String>();
        childArray = new ArrayList<List<String>>();
       
        /*-第一季-*/
        initdate();
        expandableListView_one.setAdapter(new ExpandableListViewaAdapter(ExpandableListViewDemo.this));
        
        /*-第二季-*/
//        groupArray.add("移動開發");
//        List<String> arrayList = new ArrayList<String>();
//        arrayList.add("Android");
//        arrayList.add("IOS");
//        arrayList.add("Windows Phone");
//        //組循環
//        for(int index=0;index<groupArray.size();++index)
//        {
//        	childArray.add(arrayList);
//        }
//        expandableListView_one.setAdapter(new ExpandableListViewaAdapter(ExpandableListViewDemo.this));
        
    }
    class ExpandableListViewaAdapter extends BaseExpandableListAdapter {
    	Activity activity;
    	 public  ExpandableListViewaAdapter(Activity a)  
    	    {  
    	        activity = a;  
    	    }  
       /*-----------------Child */
    	@Override
    	public Object getChild(int groupPosition, int childPosition) {
    		// TODO Auto-generated method stub
    		return childArray.get(groupPosition).get(childPosition);
    	}

    	@Override
    	public long getChildId(int groupPosition, int childPosition) {
    		// TODO Auto-generated method stub
    		return childPosition;
    	}

    	@Override
    	public View getChildView(int groupPosition, int childPosition,
    			boolean isLastChild, View convertView, ViewGroup parent) {
    		
    		String string =childArray.get(groupPosition).get(childPosition);
    		
    		return getGenericView(string);
    	}

    	@Override
    	public int getChildrenCount(int groupPosition) {
    		// TODO Auto-generated method stub
    		return childArray.get(groupPosition).size();
    	}
       /* ----------------------------Group */
    	@Override
    	public Object getGroup(int groupPosition) {
    		// TODO Auto-generated method stub
    		return getGroup(groupPosition);
    	}

    	@Override
    	public int getGroupCount() {
    		// TODO Auto-generated method stub
    		return groupArray.size();
    	}

    	@Override
    	public long getGroupId(int groupPosition) {
    		// TODO Auto-generated method stub
    		return groupPosition;
    	}

    	@Override
    	public View getGroupView(int groupPosition, boolean isExpanded,
    			View convertView, ViewGroup parent) {
    		
           String   string=groupArray.get(groupPosition);
           return getGenericView(string);
    	}

    	@Override
    	public boolean hasStableIds() {
    		// TODO Auto-generated method stub
    		return false;
    	}

    	@Override
    	public boolean isChildSelectable(int groupPosition, int childPosition) 
    	{
    		// TODO Auto-generated method stub
    		return true;
    	}
    	
    	private TextView  getGenericView(String string ) 
    	{
              AbsListView.LayoutParams  layoutParams =new AbsListView.LayoutParams(
    				ViewGroup.LayoutParams.MATCH_PARENT,
    				ViewGroup.LayoutParams.WRAP_CONTENT);
              
              TextView  textView =new TextView(activity);
              textView.setLayoutParams(layoutParams);
              
              textView.setGravity(Gravity.CENTER_VERTICAL |Gravity.LEFT);
              
              textView.setPadding(40, 0, 0, 0);
              textView.setText(string);
              return textView;
         }
    }
    
    private void initdate() 
    {
    	addInfo("語言", new String[]{"Oracle","Java","Linux","Jquery"});
    	addInfo("男人的需求", new String[]{"金錢","事業","權力","女人","房子","車","球"});
    }
    private void addInfo(String group,String []child) {
		
    	groupArray.add(group);
    	
    	List<String>  childItem =new ArrayList<String>();
    	
    	for(int index=0;index<child.length;index++)
    	{
    		childItem.add(child[index]);
    	}
         childArray.add(childItem);
	}
}

運行效果：

註釋修改以下代碼：

/*-第一季-*/
//        initdate();
//        expandableListView_one.setAdapter(new ExpandableListViewaAdapter(ExpandableListViewDemo.this));
        
        /*-第二季-*/
        groupArray.add("移動開發");
        List<String> arrayList = new ArrayList<String>();
        arrayList.add("Android");
        arrayList.add("IOS");
        arrayList.add("Windows Phone");
        //組循環
        for(int index=0;index<groupArray.size();++index)
        {
        	childArray.add(arrayList);
        }
        expandableListView_one.setAdapter(new ExpandableListViewaAdapter(ExpandableListViewDemo.this));

運行效果：

★★★★★★★★★★★★★★★★★★★★

案例二：

1.定義一個主界面expandablelistview.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >
     <ExpandableListView 
        android:id ="@+id/expandableListView"   
	    android:layout_width ="fill_parent"   
	    android:layout_height ="wrap_content"   
        >
     </ExpandableListView>
</LinearLayout>

2.在res/drawable目錄下建立樣式文件expandablelistview_groups.xml該界面是組界面：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >
     <TextView 
        android:id="@+id/textGroup"   
        android:layout_width="fill_parent"   
        android:layout_height="fill_parent"   
        android:paddingLeft="40px"   
        android:paddingTop="6px"   
        android:paddingBottom="6px"   
        android:textSize="15sp"   
        android:text="No data"   
    >   
    </TextView>
</LinearLayout>

3.在res/drawable目錄下建立樣式文件expandablelistview_child.xml；是子控件，直接顯示列表內容

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >
     <TextView     
        android:id="@+id/textChild"   
        android:layout_width="fill_parent"    
        android:layout_height="fill_parent"    
        android:paddingLeft="60px"   
        android:paddingTop="10px"   
        android:paddingBottom="10px"   
        android:textSize="20sp"   
        android:text="No Data" />  
</LinearLayout>

定義java文件：ExpandableListViewDemo_two.java

package com.test;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.security.auth.PrivateCredentialPermission;

import com.test.R;
import com.test.ExpandableListViewDemo.ExpandableListViewaAdapter;
import com.test.R.id;
import com.test.R.layout;

import android.app.Activity;
import android.os.Bundle;
import android.view.Gravity;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.widget.AbsListView;
import android.widget.BaseExpandableListAdapter;
import android.widget.ExpandableListView;
import android.widget.SimpleExpandableListAdapter;
import android.widget.TextView;

public class ExpandableListViewDemo_two extends Activity {
	/** Called when the activity is first created. */   
	private  ExpandableListView  expandableListView_one;
    @Override   
    public void onCreate(Bundle savedInstanceState)   
    {   
        super.onCreate(savedInstanceState);   
        setContentView(R.layout.expandablelistview);   
        expandableListView_one =(ExpandableListView)findViewById(R.id.expandableListView);   
        //建立二個一級條目標題    
        Map<String, String> title_1 = new HashMap<String, String>();   
        Map<String, String> title_2 = new HashMap<String, String>();   
           
        title_1.put("group", "移動開發");   
        title_2.put("group", "男人的需求");   
           
        //建立一級條目容器    
        List<Map<String, String>> gruops = new ArrayList<Map<String,String>>();   
           
        gruops.add(title_1);   
        gruops.add(title_2);   
           
        //建立二級條目內容    
           
        //內容一    
        Map<String, String> content_1 = new HashMap<String, String>();   
        Map<String, String> content_2 = new HashMap<String, String>();   
           
        content_1.put("child", "ANDROID");   
        content_2.put("child", "IOS");   
           
        List<Map<String, String>> childs_1 = new ArrayList<Map<String,String>>();   
        childs_1.add(content_1);   
        childs_1.add(content_2);   
           
        //內容二    
        Map<String, String> content_3 = new HashMap<String, String>();   
        Map<String, String> content_4 = new HashMap<String, String>();  
        Map<String, String> content_5 = new HashMap<String, String>(); 
           
        content_3.put("child", "金錢");   
        content_4.put("child", "權力");   
        content_5.put("child", "女人"); 
        List<Map<String, String>> childs_2 = new ArrayList<Map<String,String>>();   
        childs_2.add(content_3);   
        childs_2.add(content_4);  
        childs_2.add(content_5); 
           
        //存放兩個內容, 以便顯示在列表中    
        List<List<Map<String, String>>> childs = new ArrayList<List<Map<String,String>>>();   
        childs.add(childs_1);   
        childs.add(childs_2);   
           
        //建立ExpandableList的Adapter容器    
/**  
* 使用SimpleExpandableListAdapter顯示ExpandableListView  
* 參數1.上下文對象Context  
* 參數2.一級條目目錄集合  
* 參數3.一級條目對應的佈局文件 （expandablelistview_groups.xml文件 
* 參數4.fromto，就是map中的key，指定要顯示的對象  
* 參數5.與參數4對應，指定要顯示在groups中的id  
* 參數6.二級條目目錄集合  
* 參數7.二級條目對應的佈局文件  
* 參數9.與參數8對應，指定要顯示在childs中的id  
/           SimpleExpandableListAdapter adapter = new SimpleExpandableListAdapter(   
                this, gruops, R.drawable.expandablelistview_groups, new String[]{"group"}, new int[]{R.id.textGroup},    
                childs, R.drawable.expandablelistview_child, new String[]{"child"}, new int[]{R.id.textChild}   
                );   
           
        //加入列表    
        expandableListView_one.setAdapter(adapter); 
     expandableListView_one.setOnChildClickListener(listener);
    }   
    private OnChildClickListener  listener =new OnChildClickListener() {
   @Override
  public boolean onChildClick(ExpandableListView parent, View v,
    int groupPosition, int childPosition, long id) {
   // TODO Auto-generated method stub
   toast("點擊了");
   return false;
  }
 };
 private void toast(String str) {
 Toast.makeText(this, str, Toast.LENGTH_LONG).show(); 
 } 
}

上面的樣式也能夠使用系統的自帶的樣式以下：

android.R.layout.simple_expandable_list_item_1,//層顯示樣式，系統自定義

android.R.layout.simple_expandable_list_item_2,

運行效果：

案例三：若是group中有個ImageVIew將會是什麼狀況呢？

在SimpleExpandableListAdapter中有以下方法：

private void bindView(View view, Map<String, ?> data, String[] from, int[] to) {
        int len = to.length;

        for (int i = 0; i < len; i++) {
            TextView v = (TextView)view.findViewById(to[i]);
            if (v != null) {
                v.setText((String)data.get(from[i]));
            }
        }
    }

從上面的方法中能夠看出 SimpleExpandableListAdapter把因此的View都當成TextView來處理了，而不像SimpleAdapter能夠自動判斷View的類型,自動綁定，解決版本就是重寫bingview回調一下試試：

public class MyExpandableListAdapter extends BaseExpandableListAdapter{
        private void bindView(View view, Map<String, ?> data, String[] from, int[] to) {
                int len = to.length;
                boolean isBound = false;
                for (int i = 0; i < len; i++) {
                   final View v = view.findViewById(to[i]);
                 if (v!=null) {
                final Object _data = data.get(from[i]);
                String text = _data == null ? "" : data.toString();
                if (text == null) {
                    text = "";
                }
                          if (mViewBinder != null) {//若是Binder不爲空,使用Binder進行處理
                                        isBound = mViewBinder.setViewValue(v, data.get(from[i]), text);
                                }
                                if (!isBound) {//若是Binder跳過,使用原來的方法進行處理
                                        TextView _v = (TextView)v;
                                        _v.setText((String)data.get(from[i]));
                                }                               
                        }
                }
        }
}

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