Android--开发--ListView 中的item随意拖动.rar

package com.mylist; import com.mylist.ListViewInterceptor.DropListener; import android.content.Context; import android.graphics.Bitmap; import android.graphics.PixelFormat; import android.graphics.Rect; import android.util.AttributeSet; import android.util.Log; import android.view.Gravity; 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.ImageView; import android.widget.ListView; public class ListViewInterceptor extends ListView { private DropListener mDropListener; private ImageView mDragView; private int mDragPos; // which item is being dragged private int mFirstDragPos; // where was the dragged item originally private int mDragPoint; // at what offset inside the item did the user grab // it private int mCoordOffset; // the difference between screen coordinates and // coordinates in this view private Rect mTempRect = new Rect(); private final int mTouchSlop; private int mHeight; private int mUpperBound; private int mLowerBound; private WindowManager mWindowManager; private WindowManager.LayoutParams mWindowParams; private int dragndropBackgroundColor = 0x00000000; private Bitmap mDragBitmap; private int mItemHeightHalf = 32; private int mItemHeightNormal = 64; private int mItemHeightExpanded = 128; public ListViewInterceptor(Context context, AttributeSet attrs) { this(context, attrs, 0); // TODO Auto-generated constructor stub } public ListViewInterceptor(Context context, AttributeSet attrs, int defStyle) { super(context, attrs, defStyle); // TODO Auto-generated constructor stub mTouchSlop = ViewConfiguration.get(context).getScaledTouchSlop(); } @Override public boolean onTouchEvent(MotionEvent ev) { // TODO Auto-generated method stub Log.v(">>>>>>>>>>onTouchEvent", ">>>>>>>>>>onTouchEvent"); if ((mDropListener != null) && mDragView != null) { int action = ev.getAction(); switch (action) { case MotionEvent.ACTION_UP: case MotionEvent.ACTION_CANCEL: Rect r = mTempRect; mDragView.getDrawingRect(r); stopDragging(); if (mDropListener != null && mDragPos >= 0 && mDragPos < getCount()) { mDropListener.drop(mFirstDragPos, mDragPos); } unExpandViews(false); break; case MotionEvent.ACTION_DOWN: case MotionEvent.ACTION_MOVE: int x = (int) ev.getX(); int y = (int) ev.getY(); dragView(x, y); int itemnum = getItemForPosition(y); if (itemnum >= 0) { if (action == MotionEvent.ACTION_DOWN || itemnum != mDragPos) { mDragPos = itemnum; doExpansion(); Log.v(">>>doExpansion", ">>>>>>>>>>doExpansion"); } // int speed = 0; // adjustScrollBounds(y); // if (y > mLowerBound) { // // scroll the list up a bit // speed = y > (mHeight + mLowerBound) / 2 ? 16 : 4; // } else if (y < mUpperBound) { // // scroll the list down a bit // speed = y < mUpperBound / 2 ? -16 : -4; // } // if (speed != 0) { // int ref = pointToPosition(0, mHeight / 2); // if (ref == AdapterView.INVALID_POSITION) { // // we hit a divider or an invisible view, check // // somewhere else // ref = pointToPosition(0, mHeight / 2 // + getDividerHeight() + 64); // } // View v = getChildAt(ref - getFirstVisiblePosition()); // if (v != null) { // int pos = v.getTop(); // setSelectionFromTop(ref, pos - speed); // // } // } } break; } return true; } return super.onTouchEvent(ev); } @Override public boolean onInterceptTouchEvent(MotionEvent ev) { // TODO Auto-generated method stub if (mDropListener != null) { switch (ev.getAction()) { case MotionEvent.ACTION_DOWN: int x = (int) ev.getX(); int y = (int) ev.getY(); int itemnum = pointToPosition(x, y); Log.v("itemnum>>>", ">>>>>>>>" + itemnum); if (itemnum == AdapterView.INVALID_POSITION) { break; } ViewGroup item = (ViewGroup) getChildAt(itemnum - getFirstVisiblePosition()); Log.v("itemnum>>>", ">>>>>>>>" + getFirstVisiblePosition() + "---" + ev.getRawY() + "----" + ev.getY()+"-----"+item.getTop()); mDragPoint = y - item.getTop(); mCoordOffset = ((int) ev.getRawY()) - y; View dragger = item.findViewById(R.id.img); Rect r = mTempRect; // dragger.getDrawingRect(r); r.left = dragger.getLeft(); r.right = dragger.getRight(); r.top = dragger.getTop(); r.bottom = dragger.getBottom(); if ((r.left < x) && (x < r.right)) { item.setDrawingCacheEnabled(true); // Create a copy of the drawing cache so that it does not // get recycled // by the framework when the list tries to clean up memory Bitmap bitmap = Bitmap.createBitmap(item.getDrawingCache()); startDragging(bitmap, y); mDragPos = itemnum; mFirstDragPos = mDragPos; mHeight = getHeight(); int touchSlop = mTouchSlop; mUpperBound = Math.min(y - touchSlop, mHeight / 3); mLowerBound = Math.max(y + touchSlop, mHeight * 2 / 3); return false; } mDragView = null; break; } } return super.onInterceptTouchEvent(ev); } private void startDragging(Bitmap bm, int y) { stopDragging(); mWindowParams = new WindowManager.LayoutParams(); mWindowParams.gravity = Gravity.TOP; mWindowParams.x = 0; mWindowParams.y = y - mDragPoint + mCoordOffset; mWindowParams.height = WindowManager.LayoutParams.WRAP_CONTENT; mWindowParams.width = WindowManager.LayoutParams.WRAP_CONTENT; mWindowParams.flags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE | WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE | WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON | WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN; mWindowParams.format = PixelFormat.TRANSLUCENT; mWindowParams.windowAnimations = 0; ImageView v = new ImageView(getContext()); // int backGroundColor = // getContext().getResources().getColor(R.color.dragndrop_background); v.setBackgroundColor(dragndropBackgroundColor); v.setImageBitmap(bm); mDragBitmap = bm; mWindowManager = (WindowManager) getContext() .getSystemService("window"); mWindowManager.addView(v, mWindowParams); mDragView = v; } private void stopDragging() { if (mDragView != null) { WindowManager wm = (WindowManager) getContext().getSystemService( "window"); wm.removeView(mDragView); mDragView.setImageDrawable(null); mDragView = null; } if (mDragBitmap != null) { mDragBitmap.recycle(); mDragBitmap = null; } } private void dragView(int x, int y) { float alpha = 1.0f; mWindowParams.alpha = alpha; // } mWindowParams.y = y - mDragPoint + mCoordOffset; mWindowManager.updateViewLayout(mDragView, mWindowParams); } private int getItemForPosition(int y) { int adjustedy = y - mDragPoint - mItemHeightHalf; int pos = myPointToPosition(0, adjustedy); if (pos >= 0) { if (pos <= mFirstDragPos) { pos += 1; } } else if (adjustedy < 0) { pos = 0; } return pos; } private void adjustScrollBounds(int y) { if (y >= mHeight / 3) { mUpperBound = mHeight / 3; } if (y <= mHeight * 2 / 3) { mLowerBound = mHeight * 2 / 3; } } /* * Restore size and visibility for all listitems */ private void unExpandViews(boolean deletion) { for (int i = 0;; i++) { View v = getChildAt(i); if (v == null) { if (deletion) { // HACK force update of mItemCount int position = getFirstVisiblePosition(); int y = getChildAt(0).getTop(); setAdapter(getAdapter()); setSelectionFromTop(position, y); // end hack } layoutChildren(); // force children to be recreated where needed v = getChildAt(i); if (v == null) { break; } } ViewGroup.LayoutParams params = v.getLayoutParams(); params.height = mItemHeightNormal; v.setLay