ExpandableListView的使用

柔光的暖阳◎ 2022-08-05 13:30 133阅读 0赞

1、用法类似ListView，同样是在布局文件中先定义出此控件，ExpandableListVIew

<?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="match_parent"
        android:orientation="vertical" >
        
    	<ExpandableListView 
    	    android:id="@+id/expandable"
    	    android:layout_width="fill_parent"
    	    android:layout_height="fill_parent"
    	    android:background="#ffffff"
    	    android:cacheColorHint="#FFFFFF"
    	    android:listSelector="#FFFFFF">
    	</ExpandableListView>
    </LinearLayout>

简单说下的是 android:cacheColorHint="\#00000000"，这个设置可以去除拖动view时背景变成黑色的效果

android:listSelector="\#00000000" ，可以去除选中时的黄色底色

2、自定义ExapandableListView的适配器，继承BaseExpandableListViewAdapter类，并重写相关方法。

主要是我们在getChildView和getGroupView中进行设计我们现实Group和它子项的模式。然后绑定适配器，同时可以监听控件的事件。

<span style="font-size:12px;">package com.drision.test;
    
    import android.app.Activity;
    import android.content.Context;
    import android.graphics.Color;
    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.Toast;
    import android.widget.ExpandableListView.OnChildClickListener;
    import android.widget.ImageView;
    import android.widget.LinearLayout;
    import android.widget.TextView;
    
    public class ExpandableListViewActivity extends Activity {
    
    	private ExpandableListView expandable;
    	private ExpandableAdapter adapter;
    	@Override
    	protected void onCreate(Bundle savedInstanceState) {
    		super.onCreate(savedInstanceState);
    		this.requestWindowFeature(Window.FEATURE_NO_TITLE);
    		this.setContentView(R.layout.expandable_activity);
    		expandable = (ExpandableListView) this.findViewById(R.id.expandable);
    		adapter = new ExpandableAdapter();
    		expandable.setAdapter(adapter);
    		expandable.setOnChildClickListener(new OnChildClickListener(){
    
    			@Override
    			public boolean onChildClick(ExpandableListView parent, View v,
    					int groupPosition, int childPosition, long id) {
    				Toast.makeText(ExpandableListViewActivity.this, "你点击了" + adapter.getChild(groupPosition, childPosition),
                            Toast.LENGTH_SHORT).show();
    				return false;
    			}
    			
    		});
    	}
    
    	class ExpandableAdapter extends BaseExpandableListAdapter{
    		//设置组的图片
    		private int [] groupImage = new int []{R.drawable.lock_icon,R.drawable.lock_icon_2};
    		//设置组视图的文字
    		private String [] groupName = new String[]{"我的好友","陌生人"};
    		
    		//设置子视图的图片
    		private int [][] childImage = new int [][]{
       {R.drawable.woyao_add},{R.drawable.xietongapp}};
    		//设置子视图的标题
    		private String [][]  childName = new String [][]{
       {"张三"},{"李斯"}};
    		
    		private Context _this = ExpandableListViewActivity.this;
    		
    	    TextView getTextView() {
                AbsListView.LayoutParams lp = new AbsListView.LayoutParams(
                        ViewGroup.LayoutParams.FILL_PARENT, 64);
                TextView textView = new TextView(
                		_this);
                textView.setLayoutParams(lp);
                textView.setGravity(Gravity.CENTER_VERTICAL);
                textView.setPadding(36, 0, 0, 0);
                textView.setTextSize(20);
                textView.setTextColor(Color.BLACK);
                return textView;
            }
    	    
    		@Override
    		public Object getChild(int groupPosition, int childPosition) {
    			return childName[groupPosition][childPosition];
    		}
    
    		@Override
    		public long getChildId(int groupPosition, int childPosition) {
    			return childPosition;
    		}
    
    		@Override
    		public View getChildView(int groupPosition, int childPosition,
    				boolean isLastChild, View convertView, ViewGroup parent) {
    			LinearLayout ll = new LinearLayout(_this);
                ll.setOrientation(0);
                ImageView iv = new ImageView(_this);
                iv.setImageResource(childImage[groupPosition][childPosition]);
                ll.addView(iv);
                TextView textView = getTextView();
                textView.setText(getChild(groupPosition, childPosition)
                        .toString());
                ll.addView(textView);
                return ll;
    		}
    
    		@Override
    		public int getChildrenCount(int groupPosition) {
    			return childName[groupPosition].length;
    		}
    
    		@Override
    		public Object getGroup(int groupPosition) {
    			return groupName[groupPosition];
    		}
    
    		@Override
    		public int getGroupCount() {
    			return groupName.length;
    		}
    
    		@Override
    		public long getGroupId(int groupPosition) {
    			return groupPosition;
    		}
    
    		@Override
    		public View getGroupView(int groupPosition, boolean isExpanded,
    				View convertView, ViewGroup parent) {
    			// 创建一个布局，然后进行图片和文字的显示
    			LinearLayout linear = new LinearLayout(_this);
    			linear.setOrientation(0);
    			ImageView iv = new ImageView(_this);
    			iv.setImageResource(groupImage[groupPosition]);
    			iv.setPadding(50, 0, 0, 0);
    			linear.addView(iv);
    			TextView textView = getTextView();
    	        textView.setTextColor(Color.BLACK);
    	        textView.setText(getGroup(groupPosition).toString());
    	        linear.addView(textView);
    			return linear;
    		}
    
    		@Override
    		public boolean hasStableIds() {
    			return true;
    		}
    
    		@Override
    		public boolean isChildSelectable(int groupPosition, int childPosition) {
    			return true;
    		}
    		
    	}
    }
    </span>

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