前言
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！