147.泡泡窗实现下拉菜单条

功能描述：点击下拉按钮，显示出所有的条目，有删除和点击功能，点击后将条目显示。

注意：泡泡窗默认是没有焦点的。要让泡泡窗获取到焦点。假如listview的item中有Button，ImageButton,CheckBox等会强制获取焦点的view 此时，listview的item无法获取焦点，从而无法被点击 解决方法：给item的根布局增加以下属性 android:descendantFocusability="blocksDescendants"设置之后，Button获取焦点，item中其他控件也可以获取焦点,如果文本的文字过多，会被后面的图标盖住，首先设置单行android:singleLine="true"再设置右边距就盖不住android:padding="40dp"

需要添加下面三项

//让泡泡窗额度条目获取到焦点
		popupWindow.setFocusable(true);
		//设置背景图
		popupWindow.setBackgroundDrawable(new BitmapDrawable());
		popupWindow.setOutsideTouchable(true);

主布局文件activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#22000000"
    tools:context=".MainActivity" >

    <RelativeLayout 
        android:layout_marginTop="40dp"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        >
    <EditText
        android:id="@+id/et"
        android:singleLine="true"
        android:padding="40dp"
        android:layout_width="300dp"
        android:layout_height="40dp"
        />
    <ImageView 
        android:layout_width="wrap_content"
        android:layout_height="40dp"
        android:id="@+id/iv_select"
        android:layout_centerVertical="true"
        android:background="@drawable/ic_launcher"
        android:layout_alignRight="@id/et"
        />
	</RelativeLayout>
</RelativeLayout>

每一个条目的布局文件item_list.xml

<?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:padding="5dp"
    android:orientation="horizontal" >
    
    <TextView 
        android:layout_width="0dp"
    	android:layout_height="wrap_content"
    	android:drawableLeft="@drawable/ic_launcher"
    	android:gravity="center_vertical"
    	android:drawablePadding="3dp"
    	android:text="123"
    	android:id="@+id/tv_number"
    	android:layout_weight="1"
        />
    <ImageView 
        android:id="@+id/iv_delete"
        android:layout_width="wrap_content"
    	android:layout_height="wrap_content"
    	android:background="@drawable/ic_launcher"
        />
    

</LinearLayout>

逻辑代码MainActivity.java

package com.ldw.select;

import java.util.ArrayList;

import android.app.Activity;
import android.graphics.drawable.BitmapDrawable;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.PopupWindow;
import android.widget.TextView;

public class MainActivity extends Activity implements OnClickListener{

	private ImageView iv_select;
	private EditText et;
	private ArrayList<String> list = new ArrayList<String>();
	private TextView tv_number;
	private ImageView iv_delete;
	private ListView listView;
	private PopupWindow popupWindow;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        
        
        initView();
        initListener();  
        initData();
        
    }

	private void initView() {
		setContentView(R.layout.activity_main);
    	iv_select = (ImageView) findViewById(R.id.iv_select);
        et = (EditText) findViewById(R.id.et);
		
	}
    
    private void initListener() {
    	iv_select.setOnClickListener(this);
		
	}
    
    //集合中添加数据
	private void initData() {
		for(int i = 0; i< 20; i++){
			list.add(1340000000 + i + "");
		}
		
		initListView();
		
	}
	
	//初始化列表
	private void initListView(){
		listView = new ListView(this);
		//设置listView的背景图
		listView.setBackgroundResource(R.drawable.ic_launcher);
		//让listView的滚动条不可见
		listView.setVerticalScrollBarEnabled(false);
		MyAdapter adapter = new MyAdapter();
		listView.setAdapter(adapter);
		
		listView.setOnItemClickListener(new OnItemClickListener(){

			@Override
			public void onItemClick(AdapterView<?> parent, View view,
					int position, long id) {
				et.setText(list.get(position));
				//关闭泡泡窗
				popupWindow.dismiss();
				
			}
			
		});
	}
	
	//泡泡窗实现点击显示列表,泡泡窗默认是不获取焦点的
	private void showNumberList(){
		if(popupWindow == null){
		//泡泡窗的填充,设置宽高
		popupWindow = new PopupWindow(listView, et.getWidth(), 300);
		
		}
		//让泡泡窗额度条目获取到焦点
		popupWindow.setFocusable(true);
		//设置背景图
		popupWindow.setBackgroundDrawable(new BitmapDrawable());
		popupWindow.setOutsideTouchable(true);
		
		//第一个参数是依附哪一个参数下,x轴，y轴的偏移量，相对于第一个参数的左下角的位置
		popupWindow.showAsDropDown(et, 0, 0);
	}

	@Override
	public void onClick(View v){
    	switch (v.getId()){
    		case R.id.iv_select:
    			//点击弹出列表
    			showNumberList();
    			break;
    	}
    }
	
	//listView填充
	class MyAdapter extends BaseAdapter{
		
		@Override
		public int getCount() {
			return list.size();
		}

		@Override
		public Object getItem(int position) {
			return null;
		}

		@Override
		public long getItemId(int position) {
			return 0;
		}

		@Override
		public View getView(final int position, View convertView, ViewGroup parent) {
			final View view = View.inflate(MainActivity.this, R.layout.item_list, null);
			tv_number = (TextView) view.findViewById(R.id.tv_number);
			iv_delete = (ImageView) view.findViewById(R.id.iv_delete);
			
			tv_number.setText(list.get(position));
			//删除按键
			iv_delete.setOnClickListener(new OnClickListener(){

				@Override
				public void onClick(View v) {
					//删除条目
					list.remove(position);
					//更新页面
					notifyDataSetChanged();
					//根据当前条目的个数设置，当前条目的高度
					int listViewHeight = list.size() * view.getHeight();
					if(listViewHeight > 300){
						listViewHeight = 300;
					}else{
						listViewHeight = listViewHeight;
					}
					//更新泡泡窗的高度
					popupWindow.update(et.getWidth(), listViewHeight);
					//删除完了，泡泡窗小消失
					if(list.size() == 0){
						popupWindow.dismiss();
						//下拉条消失
						iv_select.setVisibility(View.GONE);
					}
				}
				
			});
			return view;
		}
		
	}

}