Android之GridView的Item移動

調用:

public class AniGridViewActivity extends Activity {    /** GridView. */    private DragGrid gridView;    TranslateAnimation left, right;    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);        com.cn.theodore.util.Configure.init(this);        gridView = (DragGrid) findViewById(R.id.gridview);        ArrayList<String> l = new ArrayList<String>();        for (int i = 0; i < 8; i++) {            l.add("" + i);        }        DateAdapter adapter = new DateAdapter(AniGridViewActivity.this, l);        gridView.setAdapter(adapter);    }}

重寫的GridView：

public class DragGrid extends GridView {    private int dragPosition;    private int dropPosition;    private int holdPosition;    private int startPosition;    private int specialPosition = -1;    private int leftBottomPosition = -1;        private int nColumns = 3;    private int nRows;    private int Remainder;        private int itemTotalCount;        private int halfItemWidth;        private ImageView dragImageView = null;    private ViewGroup dragItemView = null;    private WindowManager windowManager = null;    private WindowManager.LayoutParams windowParams = null;        private int mLastX,xtox;    private int mLastY,ytoy;    private int specialItemY;    private int leftBtmItemY;        private String LastAnimationID;        private boolean isCountXY = false;        private boolean isMoving = false;        public DragGrid(Context context, AttributeSet attrs) {        super(context, attrs);            }    public DragGrid(Context context) {        super(context);    }    boolean flag = false;    public void setLongFlag(boolean temp) {        flag = temp;    }        public boolean setOnItemLongClickListener(final MotionEvent ev) {        this.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {            @Override            public boolean onItemLongClick(AdapterView<?> arg0, View arg1,                    int arg2, long arg3) {                int x = (int) ev.getX();                int y = (int) ev.getY();                mLastX=x;                mLastY=y;                startPosition = dragPosition = dropPosition = arg2;                if (dragPosition == AdapterView.INVALID_POSITION) {                }                                ViewGroup itemView = (ViewGroup) getChildAt(dragPosition                        - getFirstVisiblePosition());                if(!isCountXY){                    halfItemWidth = itemView.getWidth()/2;                    int rows;                    itemTotalCount = getCount();                    rows = itemTotalCount/nColumns;                    Remainder = itemTotalCount%nColumns;                    nRows =  Remainder == 0 ?  rows : rows + 1;                    specialPosition = itemTotalCount - 1 - Remainder;                    if(Remainder!=1)                        leftBottomPosition = nColumns*(nRows-1);                    if(Remainder == 0 || nRows == 1)                        specialPosition = -1;                                    isCountXY = true;                }                if(specialPosition != dragPosition && dragPosition != -1){                    specialItemY = getChildAt(specialPosition).getTop();                }else{                    specialItemY = -1;                }                if(leftBottomPosition != dragPosition && dragPosition != -1){                    leftBtmItemY = getChildAt(leftBottomPosition).getTop();                }else{                    leftBtmItemY = -1;                }                dragItemView = itemView;                itemView.destroyDrawingCache();                itemView.setDrawingCacheEnabled(true);                itemView.setDrawingCacheBackgroundColor(0x000000);                Bitmap bm = Bitmap.createBitmap(itemView.getDrawingCache(true));                Bitmap bitmap = Bitmap.createBitmap(bm, 8, 8, bm.getWidth()-8, bm.getHeight()-8);                startDrag(bitmap, x, y);                hideDropItem();                itemView.setVisibility(View.INVISIBLE);                                isMoving = false;                return false;            };        });        return super.onInterceptTouchEvent(ev);    }        public void GetItemShadow(int x,int y){                    }    @Override    public boolean onInterceptTouchEvent(MotionEvent ev) {        if (ev.getAction() == MotionEvent.ACTION_DOWN) {            return setOnItemLongClickListener(ev);        }        return super.onInterceptTouchEvent(ev);    }    @Override    public boolean onTouchEvent(MotionEvent ev) {        if (dragImageView != null                && dragPosition != AdapterView.INVALID_POSITION) {            int x = (int) ev.getX();            int y = (int) ev.getY();            switch (ev.getAction()) {            case MotionEvent.ACTION_MOVE:                if(!isCountXY) {                    xtox = x-mLastX;                    ytoy = y-mLastY;                    isCountXY= true;                }                onDrag(x, y);                if(!isMoving )                    OnMove(x,y);                            break;            case MotionEvent.ACTION_UP:                stopDrag();                onDrop(x, y);                break;            }        }        return super.onTouchEvent(ev);    }    private void startDrag(Bitmap bm, int x, int y) {        stopDrag();        windowParams = new WindowManager.LayoutParams();        windowParams.gravity = Gravity.TOP | Gravity.LEFT;        windowParams.x = dragItemView.getLeft() + 8;        windowParams.y = dragItemView.getTop()+(int)(45*Configure.screenDensity);        windowParams.height = WindowManager.LayoutParams.WRAP_CONTENT;        windowParams.width = WindowManager.LayoutParams.WRAP_CONTENT;        windowParams.alpha = 0.8f;        ImageView iv = new ImageView(getContext());        iv.setImageBitmap(bm);        windowManager = (WindowManager) getContext().getSystemService(                Context.WINDOW_SERVICE);        windowManager.addView(iv, windowParams);                dragImageView = iv;    }        public  void OnMove(int x, int y){        int TempPosition = pointToPosition(x,y);        int sOffsetY = specialItemY == -1 ? y - mLastY : y - specialItemY - halfItemWidth;        int lOffsetY = leftBtmItemY == -1 ? y - mLastY : y - leftBtmItemY - halfItemWidth;        if(TempPosition != AdapterView.INVALID_POSITION && TempPosition != dragPosition){            dropPosition = TempPosition;        }else if(specialPosition != -1 && dragPosition == specialPosition && sOffsetY >= halfItemWidth){            dropPosition = (itemTotalCount - 1);        }else if(leftBottomPosition != -1 && dragPosition == leftBottomPosition && lOffsetY >= halfItemWidth){            dropPosition = (itemTotalCount - 1);        }            if(dragPosition != startPosition)            dragPosition = startPosition;        int MoveNum = dropPosition - dragPosition;        if(dragPosition != startPosition && dragPosition == dropPosition)            MoveNum = 0;        if(MoveNum != 0){            int itemMoveNum = Math.abs(MoveNum);            float Xoffset,Yoffset;            for (int i = 0;i < itemMoveNum;i++){            if(MoveNum > 0){                holdPosition = dragPosition + 1;                Xoffset = (dragPosition/nColumns == holdPosition/nColumns) ? (-1) : (nColumns -1);                Yoffset = (dragPosition/nColumns == holdPosition/nColumns) ? 0 : (-1);            }else{                holdPosition = dragPosition - 1;                Xoffset = (dragPosition/nColumns == holdPosition/nColumns) ? 1 : (-(nColumns-1));                Yoffset = (dragPosition/nColumns == holdPosition/nColumns) ? 0 : 1;            }            ViewGroup moveView = (ViewGroup)getChildAt(holdPosition);                            Animation animation = getMoveAnimation(Xoffset,Yoffset);            moveView.startAnimation(animation);            dragPosition = holdPosition;            if(dragPosition == dropPosition)                LastAnimationID = animation.toString();            final DateAdapter adapter = (DateAdapter)this.getAdapter();            animation.setAnimationListener(new Animation.AnimationListener() {                                    @Override                public void onAnimationStart(Animation animation) {                        // TODO Auto-generated method stub                    isMoving = true;                }                                    @Override                public void onAnimationRepeat(Animation animation) {                        // TODO Auto-generated method stub                                        }                                    @Override                public void onAnimationEnd(Animation animation) {                        // TODO Auto-generated method stub                    String animaionID = animation.toString();                    if(animaionID.equalsIgnoreCase(LastAnimationID)){                        adapter.exchange(startPosition, dropPosition);                        startPosition = dropPosition;                        isMoving = false;                    }                                    }            });              }       }    }        private void onDrop(int x,int y){        final DateAdapter adapter = (DateAdapter) this.getAdapter();        adapter.showDropItem(true);        adapter.notifyDataSetChanged();        }    private void onDrag(int x, int y) {        if (dragImageView != null) {            windowParams.alpha = 0.8f;            windowParams.x = (x-mLastX-xtox)+dragItemView.getLeft()+8;//            windowParams.y = (y-mLastY-ytoy)+dragItemView.getTop()+(int)(45*Configure.screenDensity);            windowParams.y = y;            windowManager.updateViewLayout(dragImageView, windowParams);        }    }        private void stopDrag() {        if (dragImageView != null) {            windowManager.removeView(dragImageView);            dragImageView = null;        }    }        private void hideDropItem(){        final DateAdapter adapter = (DateAdapter)this.getAdapter();        adapter.showDropItem(false);    }        public Animation getMoveAnimation(float x,float y){        TranslateAnimation go = new TranslateAnimation(Animation.RELATIVE_TO_SELF, 0, Animation.RELATIVE_TO_SELF, x,                 Animation.RELATIVE_TO_SELF, 0, Animation.RELATIVE_TO_SELF, y);        go.setFillAfter(true);        go.setDuration(300);            return go;    }}

GridView使用的Adapter：

public class DateAdapter extends BaseAdapter {    private Context context;    private List<String> lstDate;    private TextView txtAge;    private int holdPosition;    private boolean isChanged = false;    private boolean ShowItem = false;    public DateAdapter(Context mContext, List<String> list) {        this.context = mContext;        lstDate = list;    }    @Override    public int getCount() {        return lstDate.size();    }    @Override    public Object getItem(int position) {        return lstDate.get(position);    }    @Override    public long getItemId(int position) {        return position;    }    public void exchange(int startPosition, int endPosition) {        System.out.println(startPosition + "--" + endPosition);        holdPosition = endPosition;        Object startObject = getItem(startPosition);        System.out.println(startPosition + "========" + endPosition);        Log.d("ON","startPostion ==== " + startPosition );        Log.d("ON","endPosition ==== " + endPosition );        if(startPosition < endPosition){            lstDate.add(endPosition + 1, (String) startObject);            lstDate.remove(startPosition);        }else{            lstDate.add(endPosition,(String)startObject);            lstDate.remove(startPosition + 1);        }        isChanged = true;        notifyDataSetChanged();    }        public void showDropItem(boolean showItem){        this.ShowItem = showItem;            }    @Override    public View getView(int position, View convertView, ViewGroup parent) {        convertView = LayoutInflater.from(context).inflate(R.layout.item, null);        txtAge = (TextView) convertView.findViewById(R.id.txt_userAge);        txtAge.setText("Item" + lstDate.get(position));        if (isChanged){            if (position == holdPosition){                if(!ShowItem){                    convertView.setVisibility(View.INVISIBLE);                }            }        }        return convertView;    }}

Configure：

public class Configure {    public static int screenHeight=0;    public static int screenWidth=0;    public static float screenDensity=0;        public static void init(Activity context) {        if(screenDensity==0||screenWidth==0||screenHeight==0){            DisplayMetrics dm = new DisplayMetrics();            context.getWindowManager().getDefaultDisplay().getMetrics(dm);            Configure.screenDensity = dm.density;            Configure.screenHeight = dm.heightPixels;            Configure.screenWidth = dm.widthPixels;        }    }}

main.xml:

<?xml version="1.0" encoding="utf-8"?><RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="fill_parent"    android:layout_height="fill_parent"    android:gravity="center"    android:background="@drawable/notesbackground" >    <com.cn.theodore.util.DragGrid        android:id="@+id/gridview"        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:gravity="center"        android:numColumns="3"        android:scrollbars="vertical"        android:stretchMode="columnWidth"        android:verticalSpacing="25dp" >    </com.cn.theodore.util.DragGrid>         <!--   android:listSelector="@android:color/transparent"--></RelativeLayout>