Android listView 头部添加透明titleBar

效果图如下

activity布局：

<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"
    tools:context="com.npi.blureffect.ListViewActivity" >

      <ListView
          android:id="@+id/listView1"
          android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:layout_alignParentLeft="true" >

      </ListView>
      
        <com.npi.blureffect.ScrollableImageView
         android:id="@+id/blurred_image_header"
         android:layout_width="match_parent"
         android:layout_height="50dp"
         android:background="#e8e8e8" />
      

</RelativeLayout>

listView里的单个布局

<?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" >

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="false"
        android:layout_alignParentRight="false"
        android:layout_alignParentTop="false"
        android:layout_centerVertical="true"
        android:src="@drawable/demo02" />

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentRight="true"
        android:layout_centerVertical="true"
        android:layout_marginRight="20dp"
        android:text="Button" />

</RelativeLayout>

listView的header的布局，这里应该和头部的模糊view一样

<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"
    tools:context="com.npi.blureffect.ListViewActivity" >
      
        <com.npi.blureffect.ScrollableImageView
         android:id="@+id/blurred_image_header"
         android:layout_width="match_parent"
         android:layout_height="50dp"
         android:background="#e8e8e8" />
      

</RelativeLayout>

activity代码

package com.npi.blureffect;

import java.util.ArrayList;
import java.util.List;
import java.util.zip.Inflater;

import com.situ.android.adapter.CommonAdapter;
import com.situ.android.adapter.ViewHolder;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.Canvas;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.MeasureSpec;
import android.widget.AbsListView;
import android.widget.AbsListView.OnScrollListener;
import android.widget.ImageView;
import android.widget.ListView;

public class ListViewActivity extends Activity {
	ScrollableImageView header;
	ListView listView;
	Bitmap screen;
	View listHeader;
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_list_view);
		listView = (ListView) findViewById(R.id.listView1);
		header = (ScrollableImageView) findViewById(R.id.blurred_image_header);
		
		List<Integer> contents = new ArrayList<Integer>();
		contents.add(R.drawable.demo01);
		contents.add(R.drawable.demo02);
		contents.add(R.drawable.demo03);
		contents.add(R.drawable.demo04);
		contents.add(R.drawable.demo05);
		contents.add(R.drawable.demo06);
		contents.add(R.drawable.demo07);
		contents.add(R.drawable.demo08);
		contents.add(R.drawable.demo09);
		contents.add(R.drawable.demo10);
		contents.add(R.drawable.demo11);
		contents.add(R.drawable.demo12);
		contents.add(R.drawable.demo13);
		contents.add(R.drawable.demo14);
		contents.add(R.drawable.demo15);
		listView.setAdapter(new CommonAdapter(ListViewActivity.this,R.layout.list_activity_item,contents) {
			
			@Override
			public void convert(ViewHolder holder, int position, Object object) {
				// TODO Auto-generated method stub
				ImageView img = (ImageView)holder.getView(R.id.imageView1);
				img.setImageResource((Integer)object);
			}
		});
		
		
		initListView(listView, header);
	}

	int totalHeight=0;
	int initHeight = 0;
	private void initListView(final ListView listView,final ScrollableImageView header){
		LayoutInflater inflater = getLayoutInflater(); 
		listHeader = inflater.inflate(R.layout.list_header, null);
		listView.addHeaderView(listHeader);
		listView.setOnScrollListener(new OnScrollListener() {
			int X = 0;
			int Y = 0;
			int height = 0;
			/**
			 * 获取当前滑动的精准位置，仅能用于行高均相同的listview
			 * @param mListView
			 * @return
			 */
			public int getScrollY(final AbsListView mListView) {
				mListView.post(new Runnable() {
					
					@Override
					public void run() {
						// TODO Auto-generated method stub
						 View c = mListView.getChildAt(0);
						    if (c == null) {
						        return ;
						    }
						    int firstVisiblePosition = mListView.getFirstVisiblePosition();
						    int top = c.getTop();
//						    Log.i("Alex", "子元素的top是"+top+"头的高度是"+listHeader.getHeight()+"  :"+listHeader.getMeasuredHeight());
						    //重中之重的方法！！！！！！！！！！！！！！！！！！！！！！！
						    Log.i("Alex", "计算结果是 "+top+"+"+(firstVisiblePosition-1)+" *"+c.getHeight()+" +"+listHeader.getHeight()+"  :"+listHeader.getMeasuredHeight());
						    if(c.getHeight()==listHeader.getHeight()){
						    	height =  -top + (firstVisiblePosition) * c.getHeight() ;
						    }else{
						    	height =  -top + (firstVisiblePosition-1) * c.getHeight()+listHeader.getHeight() ;
						    }
					}
				});
			   return height;
			}
			
			@Override
			public void onScrollStateChanged(AbsListView view, int scrollState) {
				// TODO Auto-generated method stub
				Log.i("Alex", "listView滚动状态改变了:::"+scrollState);
				 switch(scrollState){  
			        case OnScrollListener.SCROLL_STATE_IDLE://空闲状态  
			            Log.i("Alex", "现在是空闲状态");
			        	break;  
			        case OnScrollListener.SCROLL_STATE_FLING://滚动状态  
			        	Log.i("Alex", "现在是滚动状态");
			            break;  
			        case OnScrollListener.SCROLL_STATE_TOUCH_SCROLL://触摸后滚动  
			        	Log.i("Alex", "现在是惯性状态");     
			            break;  
			     }  
				
			}
			
			@Override
			public void onScroll(AbsListView view, int firstVisibleItem,
					int visibleItemCount, int totalItemCount) {
				// TODO Auto-generated method stub
//				Log.i("Alex", "正在滚动。。第一个可见item是"+firstVisibleItem+" 可见item的数量是"+visibleItemCount+" /"+totalItemCount);
//				X = listView.getScrollX();
				Y = getScrollY(view);
				if(Y<initHeight){
					Log.i("Alex", "现在是刚进来");
				}
				if(Y>initHeight && Y >totalHeight-listHeader.getHeight()){
					Log.i("Alex", "正在重新截图。。。................................................................................。。。。。。。。。。。。");
					
					view.post(new Runnable() {
						
						@Override
						public void run() {
							// TODO Auto-generated method stub
							Bitmap subScreen = Blur.fastblur(ListViewActivity.this, getbBitmap(listView), 15);
							screen = concactBitmapVertical(screen, subScreen);
							subScreen.recycle();//消除内存
							totalHeight = screen.getHeight();
							header.setoriginalImage(screen);
						}
					});
					
				}
				Log.i("Alex", "现在要显示到："+Y);
				header.handleScroll(Y, 0);
			}
		});
		
		listView.post(new Runnable() {
			
			@Override
			public void run() {
				// TODO Auto-generated method stub
				screen = getbBitmap(listView);
				initHeight = screen.getHeight();
				screen = Blur.fastblur(ListViewActivity.this, screen, 15);
				totalHeight = screen.getHeight();
				header.setoriginalImage(screen);
			}
		});
	}
	
	
	 /**
	  * 截图listview，这个截图方法有bug,在快速滑动和慢速滑动的时候截图结果不同
	  * **/
	 public static Bitmap getbBitmap(ListView listView) {
	  int h = 0;
	  Bitmap bitmap = null;
	  // 获取listView实际高度
	  Log.i("Alex", "子元素数量是"+listView.getChildCount());
	  for (int i = 0; i < listView.getChildCount(); i++) {
	   h += listView.getChildAt(i).getHeight();
	  }
	  Log.d("Alex", "实际高度:" + h);
	  Log.d("Alex", "list 高度:" + listView.getHeight());
	  // 创建对应大小的bitmap
	  bitmap = Bitmap.createBitmap(listView.getWidth(), h,
	    Bitmap.Config.ARGB_8888);
	  final Canvas canvas = new Canvas(bitmap);
	  listView.draw(canvas);
	  return bitmap;
	 }
	 
	 /**
	  * 这个方法不能用于listView中的contentView，不然被测量之前的contentVIew就都没了
	  * @param view
	  * @return
	  */
	 public static Bitmap convertViewToBitmap(View view) {
		  view.measure(MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED),
		    MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
		  view.layout(0, 0, view.getMeasuredWidth(), view.getMeasuredHeight());
		  view.buildDrawingCache();
		  Bitmap bitmap = view.getDrawingCache();
		  if (bitmap != null) {
		   System.out.println("这不是nullde1");
		   Log.d("nullde1", "nullde1");
		  } else {
		   System.out.println("这nullnulllnulnlul");
		  }
		  return bitmap;
	}
	 
	 /**
		 * 将两张位图拼接成一张(横向拼接)
		 * 
		 * @param first
		 * @param second
		 * @return
		 */
		private Bitmap concactBitmapHorizantal(Bitmap first, Bitmap second) {
	                int width =first.getWidth() + second.getWidth();
	                int height = Math.max(first.getHeight(), second.getHeight());
			Bitmap result = Bitmap.createBitmap(width, height, Config.ARGB_8888);
			Canvas canvas = new Canvas(result);
			canvas.drawBitmap(first, 0, 0, null);
			canvas.drawBitmap(second, first.getWidth(), 0, null);
			return result;
		}
		/**
		 * 将两张位图拼接成一张(横向拼接)
		 * 
		 * @param first
		 * @param second
		 * @return
		 */
		private Bitmap concactBitmapVertical(Bitmap first, Bitmap second) {
			int width =Math.max(first.getWidth(), second.getWidth());
			int height = first.getHeight()+second.getHeight();
			Bitmap result = Bitmap.createBitmap(width, height, Config.ARGB_4444);
			Canvas canvas = new Canvas(result);
			canvas.drawBitmap(first, 0, 0, null);//先画第一个
			canvas.drawBitmap(second, 0, first.getHeight(), null);//在第一个的下面画第二个
			return result;
		}
		
		
}