高仿微信对话列表滑动删除效果

用过微信的都知道，微信对话列表滑动删除效果是很不错的，这个效果我们也可以有。思路其实很简单，弄个ListView，然后里面的每个item做成一个可以滑动的自定义控件即可。由于ListView是上下滑动而item是左右滑动，因此会有滑动冲突，也许你需要了解下android中点击事件的派发流程，请参考Android源码分析-点击事件派发机制。我的解决思路是这样的：重写ListView的onInterceptTouchEvent方法，在move的时候做判断，如果是左右滑动就返回false，否则返回true；重写SlideView（即自定义item控件）的onTouchEvent方法来处理滑动。整个思路没有问题，滑动冲突也解决了，可是ListView无法得到焦点了，也就是ListView无法处理点击事件了。让我们回想下问题出在哪里：我的理解是这样的，上述处理滑动本身没有问题，但是有一个副作用，就是会让外层View失去焦点且无法处理点击事件。常见的滑动冲突场景，比如launcher内部嵌入ListView却是没有问题的，因为这个时候launcher不需要获得焦点，需要获得焦点的是内部的ListView。因此，上述处理方式对于外部需要获得焦点的情况（比如外部是ListView）就不太适合了。于是我就和ttdevs探讨，发现他采用了另外一种思路，我从来没有想过还可以这样玩。下面介绍他的思路。

新的思路

不考虑那么复杂，不采用主流玩法，所有的事件均由外层的ListView做拦截，同时把事件传递给SlideView做滑动，这种实现的确可以达到效果，而且代码很简单，根本不需要处理什么复杂的滑动冲突。

 

效果

下面分别为微信和高仿效果

 

代码分析

先看SlideView是如何实现的

看layout xml：

 <com.macc.firstsecretary_UI.ListViewCompat
         android:id="@+id/list"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:background="#fff4f7f9"
         android:cacheColorHint="#00000000"
         android:divider="#dddbdb"
         android:dividerHeight="1.0px"
         android:drawSelectorOnTop="false"
         android:listSelector="@android:color/transparent"
         android:scrollbars="none" />

再看com.macc.firstsecretary_UI.ListViewCompat类的代码：

 private static final String TAG = "ListViewCompat";

     private SlideView mFocusedItemView;

     public ListViewCompat(Context context) {
         super(context);
     }

     public ListViewCompat(Context context, AttributeSet attrs) {
         super(context, attrs);
     }

     public ListViewCompat(Context context, AttributeSet attrs, int defStyle) {
         super(context, attrs, defStyle);
     }

     public void shrinkListItem(int position) {
         View item = getChildAt(position);

         if (item != null) {
             try {
                 ((SlideView) item).shrink();
             } catch (ClassCastException e) {
                 e.printStackTrace();
             }
         }
     }

     @Override
     public boolean onTouchEvent(MotionEvent event) {
         switch (event.getAction()) {
         case MotionEvent.ACTION_DOWN: {
             int x = (int) event.getX();
             int y = (int) event.getY();
             int position = pointToPosition(x, y);
             Log.e(TAG, "postion=" + position);
             if (position != INVALID_POSITION) {
                 Message data = (Message) getItemAtPosition(position);
                 mFocusedItemView = data.getSlideView();
                 Log.e(TAG, "FocusedItemView=" + mFocusedItemView);
             }
         }
         default:
             break;
         }

         if (mFocusedItemView != null) {
             mFocusedItemView.onRequireTouchEvent(event);
         }

         return true;
     }

再看SlideView.java：

 public class SlideView extends LinearLayout {

     private static final String TAG = "SlideView";

     private Context mContext;
     private LinearLayout mViewContent;
     private RelativeLayout mHolder;
     private Scroller mScroller;
     private OnSlideListener mOnSlideListener;

     private int mHolderWidth = 120;

     private int mLastX = 0;
     private int mLastY = 0;
     private static final int TAN = 2;

     private  boolean isScroller=false;//是否已经滑动
     public interface OnSlideListener {
         public static final int SLIDE_STATUS_OFF = 0;
         public static final int SLIDE_STATUS_START_SCROLL = 1;
         public static final int SLIDE_STATUS_ON = 2;

         /**
          * @param view current SlideView
          * @param status SLIDE_STATUS_ON or SLIDE_STATUS_OFF
          */
         public void onSlide(View view, int status);
     }

     public SlideView(Context context) {
         super(context);
         initView();
     }

     public SlideView(Context context, AttributeSet attrs) {
         super(context, attrs);
         initView();
     }

     private void initView() {
         mContext = getContext();
         mScroller = new Scroller(mContext);

         setOrientation(LinearLayout.HORIZONTAL);
         View.inflate(mContext, R.layout.slide_view_merge, this);
         mViewContent = (LinearLayout) findViewById(R.id.view_content);
         mHolderWidth = Math.round(TypedValue.applyDimension(
                 TypedValue.COMPLEX_UNIT_DIP, mHolderWidth, getResources()
                         .getDisplayMetrics()));
     }

     public void setButtonText(CharSequence text) {
         ((TextView)findViewById(R.id.delete)).setText(text);
     }

     public void setContentView(View view) {
         mViewContent.addView(view);
     }

     public void setOnSlideListener(OnSlideListener onSlideListener) {
         mOnSlideListener = onSlideListener;
     }

     public void shrink() {
         if (getScrollX() != 0) {
             this.smoothScrollTo(0, 0);
         }
     }

     public void onRequireTouchEvent(MotionEvent event) {
         int x = (int) event.getX();
         int y = (int) event.getY();
         int scrollX = getScrollX();
         Log.d(TAG, "x=" + x + "  y=" + y);

         switch (event.getAction()) {
         case MotionEvent.ACTION_DOWN: {
             if (!mScroller.isFinished()) {
                 mScroller.abortAnimation();
             }
             if (mOnSlideListener != null) {
                 mOnSlideListener.onSlide(this,
                         OnSlideListener.SLIDE_STATUS_START_SCROLL);
             }
             break;
         }
         case MotionEvent.ACTION_MOVE: {
             int deltaX = x - mLastX;
             int deltaY = y - mLastY;
             if (Math.abs(deltaX) < Math.abs(deltaY) * TAN) {
                 break;
             }

             int newScrollX = scrollX - deltaX;
             if (deltaX != 0) {
                 if(isScroller){
                     this.shrink();
                 }else{
                     if (newScrollX < 0) {
                         newScrollX = 0;
                     } else if (newScrollX > mHolderWidth) {
                         newScrollX = mHolderWidth;
                     }
                     this.scrollTo(newScrollX, 0);
                 }
             }
             break;
         }
         case MotionEvent.ACTION_UP: {
             int newScrollX = 0;
             if (scrollX - mHolderWidth * 0.75 > 0) {
                 newScrollX = mHolderWidth;
             }
             if(isScroller){
                 this.shrink();
                 isScroller=false;
             }else{
                 this.smoothScrollTo(newScrollX, 0);
                 if (mOnSlideListener != null) {
                     mOnSlideListener.onSlide(this,
                             newScrollX == 0 ? OnSlideListener.SLIDE_STATUS_OFF
                                     : OnSlideListener.SLIDE_STATUS_ON);
                 }
                 isScroller=true;
             }
             break;
         }
         default:
             break;
         }

         mLastX = x;
         mLastY = y;
     }

     private void smoothScrollTo(int destX, int destY) {
         // 缓慢滚动到指定位置
         int scrollX = getScrollX();
         int delta = destX - scrollX;
         mScroller.startScroll(scrollX, 0, delta, 0, Math.abs(delta) * 3);
         invalidate();
     }

     @Override
     public void computeScroll() {
         if (mScroller.computeScrollOffset()) {
             scrollTo(mScroller.getCurrX(), mScroller.getCurrY());
             postInvalidate();
         }
     }

上述代码做了很详细的说明，这就是滑动控件的完整代码，大家要明白的是：你所添加的view都是加在SlideView的子View : view_content中的，而不是直接加在SlideView中，只有这样我们才方便做滑动效果。

 

 

最后一步我们来看看适配器里面的代码：

 public class Carpa_MySelf_MessageCenterAdapter extends BaseAdapter implements OnSlideListener,OnClickListener{

     private LayoutInflater inflater;
     private List<Message> messages;
     private Context context;
     private SlideView mSlideView;
     private int position;//删除位置数据
     private Handler handler;
     public Carpa_MySelf_MessageCenterAdapter(Context context,ArrayList<Message> messages,Handler handler){
         setData(messages);
         this.context=context;
         inflater=LayoutInflater.from(context);
         this.handler=handler;
     }
     public void setData(ArrayList<Message> messages){
         if(messages==null){
             this.messages=new ArrayList<Message>();
         }else{
             this.messages=messages;
         }
     }
     public void setPosition(int position){
         this.position=position;
     }
     @Override
     public int getCount() {
         // TODO Auto-generated method stub
         return messages.size();
     }

     @Override
     public Object getItem(int position) {
         // TODO Auto-generated method stub
         return messages.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) {
          ViewHolder holder;
          SlideView slideView = (SlideView) convertView;
          if (slideView == null) {
              View itemView = inflater.inflate(R.layout.carpa_myself_message_center_item, null);

              slideView = new SlideView(context);
              slideView.setContentView(itemView);

              holder = new ViewHolder(slideView);
              slideView.setOnSlideListener(Carpa_MySelf_MessageCenterAdapter.this);
              slideView.setTag(holder);
          } else {
              holder = (ViewHolder) slideView.getTag();
          }
          Message msgMessage=messages.get(position);
          msgMessage.setSlideView(slideView);
          msgMessage.getSlideView().shrink();
          String sourceString=msgMessage.getSourceStr();
          holder.tvContent.setText("内容:"+msgMessage.getContentStr());
          holder.tvTime.setText(UtilTools.fromatDate(msgMessage.getTimeStr()));
          holder.deleteHolder.setOnClickListener(Carpa_MySelf_MessageCenterAdapter.this);
          if(sourceString.equals("Traffic")){
              holder.tvSource.setText("信息来源:66");
              holder.iView.setBackgroundResource(R.drawable.carpa_wz);
          }else if(sourceString.equals("DaiJia")){
              holder.tvSource.setText("信息来源:99");
              holder.iView.setBackgroundResource(R.drawable.car_deldrive);
          }else if(sourceString.equals("Nianjian")){
              holder.tvSource.setText("信息来源:33");
              holder.iView.setBackgroundResource(R.drawable.car_yearcheck);
          }else if(sourceString.equals("JiaSZ")){
              holder.tvSource.setText("信息来源:88");
              holder.iView.setBackgroundResource(R.drawable.car_zjbl);
          }else if(sourceString.equals("HKJiaSZ")){
              holder.tvSource.setText("信息来源:11");
              holder.iView.setBackgroundResource(R.drawable.car_hongkong);
          }
          return slideView;
     }
     class ViewHolder {
         public ImageView iView;
         public TextView tvSource;
         public TextView tvTime;
         public TextView tvContent;
         public ViewGroup deleteHolder;

         ViewHolder(View view) {
             iView=(ImageView)view.findViewById(R.id.message_center_iv);
             tvSource = (TextView) view.findViewById(R.id.message_center_source);
             tvTime = (TextView) view.findViewById(R.id.message_center_time);
             tvContent = (TextView) view.findViewById(R.id.message_center_content);
             deleteHolder = (ViewGroup)view.findViewById(R.id.holder);
         }
     }
     @Override
     public void onClick(View v) {
         // TODO Auto-generated method stub
         if (v.getId() == R.id.holder) {
             Log.e("info", "onClick v=" + v);
 //            messages.remove(position);
 //            this.notifyDataSetChanged();
             handler.sendEmptyMessage(Tab_MySelf_MessageCenter.HANDLER_DELETE);
         }
     }
     @Override
     public void onSlide(View view, int status) {
         // TODO Auto-generated method stub
         if (mSlideView != null && mSlideView != view) {
             mSlideView.shrink();
         }

         if (status == SLIDE_STATUS_ON) {
             mSlideView = (SlideView) view;
         }
     }

代码已贴完毕！仅供参考,谢谢！