Android listView 头部添加透明titleBar

﹏ヽ暗。殇╰゛Y 2022-08-18 15:28 158阅读 0赞

效果图如下

![Center][]

activity布局：

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

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;
    		}
    		
    		
    }

[Center]: /images/20220731/8b53017f47b14508b73664670c99fa92.png