高仿 美团 向左滑动删除条目

<?xml version="1.0" encoding="UTF⑻"?> <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="80dip" android:background="#FF5555" > <TextView android:id="@+id/tv_show_info" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_marginRight="10dip" android:gravity="right|center_vertical" android:padding="15dip" android:text="向左滑动删除" android:textColor="#FFFFFF" /> <LinearLayout android:layout_width="fill_parent" android:layout_height="match_parent" android:background="#00FFFFFF" > <LinearLayout android:layout_width="fill_parent" android:layout_height="match_parent" android:background="#FFFFFF" > <TextView android:id="@+id/list_item" android:layout_width="match_parent" android:layout_height="match_parent" android:gravity="center" android:padding="15dip" android:text="ad" android:textSize="18sp" /> </LinearLayout> </LinearLayout> </FrameLayout>

package com.example.customui.view; import android.content.Context; import android.util.AttributeSet; import android.view.GestureDetector; import android.view.GestureDetector.OnGestureListener; import android.view.MotionEvent; import android.view.View; import android.view.ViewConfiguration; import android.view.ViewGroup; import android.view.WindowManager; import android.widget.AdapterView; import android.widget.ListView; import android.widget.Scroller; import com.example.customui.util.Logger; public class SwipeListView extends ListView { /** * 手势辨认 */ private GestureDetector mGestureDetector; /** * 滑动类 */ private Scroller mScroller; /** * 需要移动的view */ private View currentMoveView; private int downX; private int downY; /** * 将手指按下时的坐标转换成listview的item的位置 */ private int slidePosition; /** * 是不是在滑动 */ private boolean isSlide; //快速滑动 // private boolean isFling; private int mTouchSlop; /** * 屏幕宽度 */ private int screenWidth; /** * listview item */ private ViewGroup viewGroup; private static final int SNAP_VELOCITY = 600; public SwipeListView(Context context) { super(context); init(context); } public SwipeListView(Context context, AttributeSet attrs) { super(context, attrs); init(context); } private void init(Context context){ mScroller = new Scroller(context); mTouchSlop = ViewConfiguration.get(getContext()).getScaledTouchSlop(); screenWidth = ((WindowManager) context.getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay().getWidth(); mGestureDetector = new GestureDetector(context,new OnGestureListener() { @Override public boolean onSingleTapUp(MotionEvent e) { return false; } @Override public void onShowPress(MotionEvent e) { } @Override public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) { if (isSlide && currentMoveView!=null) { if (listener!=null) { listener.scroll(currentMoveView.getScrollX(), viewGroup); } currentMoveView.scrollBy((int)distanceX, 0); } return false; } @Override public void onLongPress(MotionEvent e) { } @Override public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) { // if (isSlide && (e2.getX()-e1.getX())<0) { // isFling = true; // Logger.getLogger().i("==============> 快速滑动"+(e2.getX()-e1.getX())); // } return false; } @Override public boolean onDown(MotionEvent e) { return false; } }); } @Override public boolean dispatchTouchEvent(MotionEvent event) { switch (event.getAction()) { case MotionEvent.ACTION_DOWN: { Logger.getLogger().i("--------dispatchTouchEvent down--------> "); if (!mScroller.isFinished() || isSlide) { return super.dispatchTouchEvent(event); } downX = (int) event.getX(); downY = (int) event.getY(); Logger.getLogger().i("-------------downX= "+downX); slidePosition = pointToPosition(downX, downY); // 无效的position, 不做任何处理;isSlide避免多个手指按下时影响isFling的值，致使被删除 if (slidePosition == AdapterView.INVALID_POSITION) { return super.dispatchTouchEvent(event); } // 获得我们点击的item view viewGroup = (ViewGroup) getChildAt(slidePosition - getFirstVisiblePosition()); //需要1定的view currentMoveView = viewGroup.getChildAt(1); break; } case MotionEvent.ACTION_MOVE:{ int x = (int) (event.getX()-downX); int y = (int) (event.getY() -downY); // Logger.getLogger().i("-------------x= "+x+" y= "+y+" mTouchSlop:"+mTouchSlop); if (Math.abs(x)>mTouchSlop && Math.abs(x)>Math.abs(y) && x<0 ) { isSlide = true; } break; } } return super.dispatchTouchEvent(event); } @Override public boolean onTouchEvent(MotionEvent ev) { mGestureDetector.onTouchEvent(ev); if (isSlide) { if (!mScroller.isFinished()) { return true; } switch (ev.getAction()) { case MotionEvent.ACTION_DOWN:{ downX = (int) ev.getX(); break; } case MotionEvent.ACTION_CANCEL: case MotionEvent.ACTION_UP:{ /*if (isFling || isRemoveItem()) { if (isFling && this.listener!=null ) { Logger.getLogger().i("滑动删除。。"); this.listener.removeItem(slidePosition); }else*/ if (isRemoveItem() && this.listener!=null) { this.listener.removeItem(slidePosition); mScroller.startScroll(currentMoveView.getScrollX(), 0,screenWidth, 0,Math.abs(300)); }else { int delta = currentMoveView.getScrollX(); mScroller.startScroll(currentMoveView.getScrollX(), 0,-delta, 0,Math.abs(500)); } postInvalidate(); } } return true; } return super.onTouchEvent(ev); } @Override public void computeScroll() { // 调用startScroll的时候scroller.computeScrollOffset()返回true， if (mScroller.computeScrollOffset()) { // 让ListView item根据当前的转动偏移量进行转动 currentMoveView.scrollTo(mScroller.getCurrX(), 0); postInvalidate(); // 转动动画结束的时候调用回调接口 if (mScroller.isFinished()) { currentMoveView.scrollTo(0, 0); if (this.listener!=null && isSlide) { this.listener.scrollFinish(); } isSlide = false; } } } private boolean isRemoveItem(){ if (currentMoveView.getScrollX()>screenWidth/2) { return true; } return false; } private RemoveItemListViewListener listener; public void setRemoveItemListViewListener(RemoveItemListViewListener listener){ this.listener = listener; } public interface RemoveItemListViewListener{ public void removeItem(int pos); public void scroll(float scrollX,View view); public void scrollFinish(); } }

package com.example.customui.activity; import java.util.ArrayList; import java.util.List; import android.R.integer; import android.content.Context; import android.os.Bundle; import android.view.View; import android.view.WindowManager; import android.view.animation.AlphaAnimation; import android.view.animation.Animation; import android.view.animation.ScaleAnimation; import android.widget.ArrayAdapter; import android.widget.TextView; import com.example.customui.BaseActivity; import com.example.customui.R; import com.example.customui.adapter.CommonAdapter; import com.example.customui.adapter.ViewHolder; import com.example.customui.util.DensityUtil; import com.example.customui.util.Logger; import com.example.customui.view.SwipeListView; import com.example.customui.view.SwipeListView.RemoveItemListViewListener; public class SwipeListViewActivity extends BaseActivity { private SwipeListView mListView; private List<String> dataSourceList; private ArrayAdapter mAdapter; private int screenWidth; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.swipe_listview_main); mListView = (SwipeListView) findViewById(R.id.lv_data); screenWidth = ((WindowManager) getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay().getWidth(); dataSourceList = new ArrayList<String>(); for (int i = 0; i < 20; i++) { dataSourceList.add("item "+i); } mAdapter = new ArrayAdapter(getApplicationContext(), R.layout.list_view_item,R.id.list_item,dataSourceList); mListView.setAdapter(mAdapter); mListView.setRemoveItemListViewListener(new RemoveItemListViewListener() { private TextView textView; @Override public void removeItem(int pos) { position = pos; } @Override public void scroll(float scrollX, View view) { if (textView==null) { textView = (TextView) view.findViewById(R.id.tv_show_info); } int fontSize=1; float alpha=0.0f; if (scrollX>screenWidth/3) { alpha=1.0f; fontSize=maxFontSize; }else { alpha = scrollX/(screenWidth/3); fontSize = (int) (alpha * maxFontSize); } textView.setAlpha(alpha); textView.setTextSize(fontSize); } @Override public void scrollFinish() { textView=null; if (position>=0) { Logger.getLogger().i("----------------------->删除的位置： "+position); dataSourceList.remove(position); mAdapter.notifyDataSetChanged(); position= ⑴; } } }); } private int position=⑴; private int maxFontSize=22; }