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运用手势操作ListView中的Item

时间:2023-04-06 21:35:19浏览次数:45  
标签:手势 public stub Item Auto Override ListView TODO method


如下面这个图:



需要实现的功能是:用手指在某条记录上从左往右划一下,出现一条横线,用于表示这个菜已经上过了;倒过来划,取消这条横线,表示这个菜没上过。


如何实现呢?


看我的吧!


首先需要一个Item的布局,在布局的最上方有一个ImageView用于显示这条横线,如果没有就把这个ImageView背景设置成透明,这个ImageView同这条记录等宽等高!


布局如下:

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"
    android:layout_height="@dimen/list_item_height" >

    <LinearLayout
        android:id="@+id/container"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:gravity="center_vertical"
        android:orientation="horizontal" >

        <TextView
            android:id="@+id/tv_0"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="2"
            android:gravity="center"
            android:paddingBottom="20dp"
            android:paddingTop="20dp"
            android:singleLine="true"
            android:text="名称"
            android:textColor="@color/white"
            android:textSize="@dimen/font_xxxbig" />

            <TextView
                android:id="@+id/tv_1"
                android:layout_width="0dp"
                android:layout_height="wrap_content"
                android:layout_gravity="center"
                android:gravity="center"
                android:paddingBottom="20dp"
                android:paddingTop="20dp"
                android:singleLine="true"
                android:text="数量"
                android:textColor="@color/white"
                android:textSize="@dimen/font_xxxbig"
               android:layout_weight="1"
               />


        <TextView
            android:id="@+id/tv_2"
            android:layout_width="0dp"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:gravity="center"
            android:paddingBottom="20dp"
            android:paddingTop="20dp"
            android:singleLine="true"
            android:text="价格"
            android:textColor="@color/white"
            android:textSize="@dimen/font_xxxbig" />
    </LinearLayout>

    <ImageView
        android:id="@+id/iv_line"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:visibility="visible" />

</FrameLayout>




然后就是写ListView了:


listView = (ListView) findViewById(R.id.listView);
		listView.setOnItemClickListener(onItemClickListener);
		listView.setOnTouchListener(new View.OnTouchListener() {
			
			@Override
			public boolean onTouch(View v, MotionEvent event) {
				// TODO Auto-generated method stub
				mDetector.onTouchEvent(event);
				return false;
			}
		});



实现手势:


mDetector=new GestureDetector(new GestureDetector.OnGestureListener() {
			
			@Override
			public boolean onSingleTapUp(MotionEvent e) {
				// TODO Auto-generated method stub
				return false;
			}
			
			@Override
			public void onShowPress(MotionEvent e) {
				// TODO Auto-generated method stub
				
			}
			
			@Override
			public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX,
					float distanceY) {
				// TODO Auto-generated method stub
				return false;
			}
			
			@Override
			public void onLongPress(MotionEvent e) {
				// TODO Auto-generated method stub
				
			}
			
			@Override
			public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
					float velocityY) {
				// TODO Auto-generated method stub
				final int FLING_MIN_DISTANCE = 100, FLING_MIN_VELOCITY = 200;  
		        if (e2.getX() - e1.getX() > FLING_MIN_DISTANCE && Math.abs(velocityX) > FLING_MIN_VELOCITY) {  //从左往右
		        	if(view!=null){
		        		Combos instance=(Combos)view.getTag();
		        		if(instance!=null){

			            	if(instance.getStatus()==ST_NORMAL){
				            	instance.setStatus(ST_FINISH);
				            	adapter.notifyDataSetChanged();
				            	//dosomething()
			            		
			            	}
			            	
			            }
		        	}
		        }
		        else if(e1.getX() - e2.getX() > FLING_MIN_DISTANCE && Math.abs(velocityX) > FLING_MIN_VELOCITY){//从右往左
		        	if(view!=null){
		        		Combos instance=(Combos)view.getTag();
		        		if(instance!=null){
		        			
			            	if(instance.getStatus()==ST_FINISH){
				            	instance.setStatus(ST_NORMAL);
				            	adapter.notifyDataSetChanged();
				            	//dosomething()

			            	}
			            }
		        	}
		        }
				return false;
			}
			
			@Override
			public boolean onDown(MotionEvent e) {
				// TODO Auto-generated method stub
				return true;
			}
		});
	};




再下来就要实现Adapter,提供一段伪代码:


class DetailAdapter extends BaseAdapter {

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

		@Override
		public Object getItem(int position) {
			// TODO Auto-generated method stub
			return selectedList.get(position);
		}

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

		@Override
		public View getView(int position, View convertView, ViewGroup parent) {
			// TODO Auto-generated method stub
			final Combos instance = selectedList.get(position);
			
				convertView = LayoutInflater.from(context).inflate(R.layout.item_for_consume_detail_activity, null);
			
				
				ImageView iv_line = (ImageView) convertView.findViewById(R.id.iv_line);
				
				//根据状态判断该显示“线”还是“透明”
				if(instance.getStatus()==ST_FINISH){
					iv_line.setBackgroundResource(R.drawable.line_huacai);
				}else{
					iv_line.setBackgroundColor(Color.TRANSPARENT);
				}
				iv_line.setTag(instance);
				iv_line.setOnTouchListener(new View.OnTouchListener() {
					
					@Override
					public boolean onTouch(View v, MotionEvent event) {
						// TODO Auto-generated method stub
						view=v;
						return false;
					}
				});
			
			return convertView;
		}

	}




这里对iv_line也要实现OnTouchListener,并且view是个全局变量,需要在手势当中判断一下if(view!=null),确保程序没问题,并且获得对象view.getTag()。最后一定要返回false,确保ListView的OnTouchListener能够继续下去!



整个触摸流程是:


先ImageView中的onTouch起作用-->在ListView中的onTouch起作用-->手势

  • 运用手势操作ListView中的Item_ide

  • 大小: 35.3 KB
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标签:手势,public,stub,Item,Auto,Override,ListView,TODO,method
From: https://blog.51cto.com/u_5454003/6174170

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