package com.jj.draggrid; import java.util.logging.Handler; import com.jj.draggrid.MainActivity.DragGridAdapter; import android.content.Context; import android.graphics.Bitmap; import android.graphics.PixelFormat; import android.util.AttributeSet; import android.util.Log; import android.view.Gravity; import android.view.MotionEvent; import android.view.View; import android.view.ViewGroup; import android.view.WindowManager; import android.widget.AdapterView; import android.widget.BaseAdapter; import android.widget.GridView; import android.widget.ImageView; import android.widget.Toast; /*** * 自定义拖拽GridView * * @author zhangjia * */ public class DragGridView extends GridView { private WindowManager windowManager;// windows窗口控制类 private WindowManager.LayoutParams windowParams;// 用于控制拖拽项的显示的参数 private int scaledTouchSlop;// 判断滑动的一个距离,scroll的时候会用到(24) private ImageView dragImageView;// 被拖拽的项(item)，其实就是一个ImageView private int dragSrcPosition;// 手指拖动项原始在列表中的位置 private int dragPosition;// 手指点击准备拖动的时候,当前拖动项在列表中的位置. private int dragPointX;// 在当前数据项中的位置 private int dragPointY;// 在当前数据项中的位置 private int dragOffsetX;// 当前视图和屏幕的距离(这里只使用了x方向上) private int dragOffsetY;// 当前视图和屏幕的距离(这里只使用了y方向上) private int upScrollBounce;// 拖动的时候，开始向上滚动的边界 private int downScrollBounce;// 拖动的时候，开始向下滚动的边界 private int temChangId;// 临时交换id private boolean isDoTouch = false;// touch是否可用 private boolean isHide = false;// 是否隐藏 private Handler handler; public void setDoTouch(boolean isDoTouch) { this.isDoTouch = isDoTouch; } public DragGridView(Context context, AttributeSet attrs) { super(context, attrs); } @Override public boolean onInterceptTouchEvent(MotionEvent ev) { if (ev.getAction() == MotionEvent.ACTION_DOWN) { int x = (int) ev.getX(); int y = (int) ev.getY(); temChangId = dragSrcPosition = dragPosition = pointToPosition(x, y); if (dragPosition == AdapterView.INVALID_POSITION) { return super.onInterceptTouchEvent(ev); } ViewGroup itemView = (ViewGroup) getChildAt(dragPosition - getFirstVisiblePosition()); dragPointX = x - itemView.getLeft(); dragPointY = y - itemView.getTop(); dragOffsetX = (int) (ev.getRawX() - x); dragOffsetY = (int) (ev.getRawY() - y); View dragger = itemView.findViewById(R.id.drag_grid_item); /*** * 判断是否选中拖动图标 */ if (dragger != null && dragPointX > dragger.getLeft() && dragPointX < dragger.getRight() && dragPointY > dragger.getTop() && dragPointY < dragger.getBottom() + 20) { upScrollBounce = getHeight() / 4; downScrollBounce = getHeight() * 3 / 4; itemView.setDrawingCacheEnabled(true); Bitmap bm = Bitmap.createBitmap(itemView.getDrawingCache()); startDrag(bm, x, y);// 初始话映像 dragger.setVisibility(View.INVISIBLE);// 隐藏该项. } } return super.onInterceptTouchEvent(ev); } @Override public boolean onTouchEvent(MotionEvent ev) { if (dragImageView != null && dragPosition != INVALID_POSITION && isDoTouch) { int action = ev.getAction(); switch (action) { /*** * */ case MotionEvent.ACTION_UP: int upX = (int) ev.getX(); int upY = (int) ev.getY(); stopDrag();// 删除映像 onDrop(upX, upY);// 松开 // isDoTouch = false; break; /*** * 拖拽item * */ case MotionEvent.ACTION_MOVE: int moveX = (int) ev.getX(); int moveY = (int) ev.getY(); onDrag(moveX, moveY);// 拖拽 break; case MotionEvent.ACTION_DOWN: int downX = (int) ev.getX(); int downY = (int) ev.getY(); onHide(downX, downY);// 隐藏该项 break; default: break; } return true; } return super.onTouchEvent(ev); } /** * 准备拖动，初始化拖动项的图像 * * @param bm * @param y */ public void startDrag(Bitmap bm, int x, int y) { windowParams = new WindowManager.LayoutParams(); windowParams.gravity = Gravity.TOP | Gravity.LEFT; windowParams.x = x - dragPointX + dragOffsetX; windowParams.y = y - dragPointY + dragOffsetY; windowParams.width = WindowManager.LayoutParams.WRAP_CONTENT; windowParams.height = WindowManager.LayoutParams.WRAP_CONTENT; windowParams.flags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE | WindowManager.LayoutParams.FLAG_NOT_TOUCHABLE | WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON | WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN; windowParams.windowAnimations = 0; ImageView imageView = new ImageView(getContext()); imageView.setImageBitmap(bm); windowManager = (WindowManager) getContext().getSystemService("window"); windowManager.addView(imageView, windowParams); dragImageView = imageView; } /*** * 拖动时时change */ private void onChange(int x, int y) { // 获取适配器 DragGridAdapter adapter = (DragGridAdapter) getAdapter(); // 数据交换 if (dragPosition < getAdapter().getCount()) { // 不相等的情况下要进行换位,相等的情况下说明正在移动 if (dragPosition != temChangId) { adapter.update(temChangId, dragPosition);// 进行换位 temChangId = dragPosition;// 将点击最初所在位置position付给临时的，用于判断是否换位. } } // 为了避免滑动到分割线的时候，返回-1的问题 int tempPosition = pointToPosition(x, y); if (tempPosition != INVALID_POSITION) { dragPosition = tempPosition; } } /*** * 拖动执行，在Move方法中执行 * * @param x * @param y */ public void onDrag(int x, int y) { // 移动 if (dragImageView != null) { windowParams.alpha = 0.8f; windowParams.x = x - dragPointX + dragOffsetX; windowParams.y = y - dragPointY + dragOffsetY; windowManager.updateViewLayout(dragImageView, windowParams); } onChange(x, y);// 时时交换 // 滚动 if (y < upScrollBounce || y > downScrollBounce) { // 使用setSelection来实现滚动 setSelection(dragPosition); } } /*** * 隐藏该选项 */ private void onHide(int x, int y) { // 获取适配器 DragGridAdapter adapter = (DragGridAdapter) getAdapter(); // 为了避免滑动到分割线的时候，返回-1的问题 int tempPosition = pointToPosition(x, y); if (tempPosition != INVALID_POSITION) { dragPosition = tempPosition; } adapter.setIsHidePosition(dragPosition); } /** * 停止拖动，删除影像 */ public void stopDrag() { if (dragImageView != null) { windowManager.removeView(dragImageView); dragImageView = null; } } /*** * 拖动放下的时候 * * @param x * @param y */ public void onDrop(int x, int y) { DragGridAdapter adapter = (DragGridAdapter) getAdapter(); adapter.setIsHidePosition(-1);// 不进行隐藏 } }