/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.android.settings.cyanogenmod;
import com.android.settings.R;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.PixelFormat;
import android.graphics.Rect;
import android.util.AttributeSet;
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 TouchInterceptor extends ListView {
private ImageView mDragView;
private WindowManager mWindowManager;
private WindowManager.LayoutParams mWindowParams;
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 DragListener mDragListener;
private DropListener mDropListener;
private int mUpperBound;
private int mLowerBound;
private int mHeight;
private Rect mTempRect = new Rect();
private Bitmap mDragBitmap;
private final int mTouchSlop;
private int mItemHeightNormal;
private int mItemHeightExpanded;
private int mItemHeightHalf;
public TouchInterceptor(Context context, AttributeSet attrs) {
super(context, attrs);
mTouchSlop = ViewConfiguration.get(context).getScaledTouchSlop();
Resources res = getResources();
mItemHeightNormal = res.getDimensionPixelSize(R.dimen.normal_height);
mItemHeightHalf = mItemHeightNormal / 2;
mItemHeightExpanded = res.getDimensionPixelSize(R.dimen.expanded_height);
}
@Override
public boolean onInterceptTouchEvent(MotionEvent ev) {
if (mDragListener != null || mDropListener != null) {
switch (ev.getAction()) {
case MotionEvent.ACTION_DOWN:
int x = (int) ev.getX();
int y = (int) ev.getY();
int itemnum = pointToPosition(x, y);
if (itemnum == AdapterView.INVALID_POSITION) {
break;
}
ViewGroup item = (ViewGroup) getChildAt(itemnum - getFirstVisiblePosition());
mDragPoint = y - item.getTop();
mCoordOffset = ((int) ev.getRawY()) - y;
View dragger = item.findViewById(R.id.grabber);
Rect r = mTempRect;
dragger.getDrawingRect(r);
// The dragger icon itself is quite small, so pretend the
// touch area is bigger
if (x < r.right * 2) {
// Fix x position while dragging
int[] itemPos = new int[2];
item.getLocationOnScreen(itemPos);
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, itemPos[0], 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;
}
stopDragging();
break;
}
}
return super.onInterceptTouchEvent(ev);
}
/*
* pointToPosition() doesn't consider invisible views, but we need to, so
* implement a slightly different version.
*/
private int myPointToPosition(int x, int y) {
if (y < 0) {
// when dragging off the top of the screen, calculate position
// by going back from a visible item
int pos = myPointToPosition(x, y + mItemHeightNormal);
if (pos > 0) {
return pos - 1;
}
}
Rect frame = mTempRect;
final int count = getChildCount();
for (int i = count - 1; i >= 0; i--) {
final View child = getChildAt(i);
child.getHitRect(frame);
if (frame.contains(x, y)) {
return getFirstVisiblePosition() + i;
}
}
return INVALID_POSITION;
}
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) {
// this shouldn't happen anymore now that myPointToPosition deals
// with this situation
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.setLayoutParams(params);
v.setVisibility(View.VISIBLE);
v.setDrawingCacheEnabled(false); //Resets the drawing cache, the positions might have changed. We don't want the cache to be wrong.
}
}
/*
* Adjust visibility and size to make it appear as though an item is being
* dragged around and other items are making room for it: If dropping the
* item would result in it still being in the same place, then make the
* dragged listitem's size normal, but make the item invisible. Otherwise,
* if the dragged listitem is still on screen, make it as small as possible
* and expand the item below the insert point. If the dragged item is not on
* screen, only expand the item below the current insertpoint.
*/
private void doExpansion() {
int childnum = mDragPos - getFirstVisiblePosition();
if (mDragPos > mFirstDragPos) {
childnum++;
}
View first = getChildAt(mFirstDragPos - getFirstVisiblePosition());
for (int i = 0;; i++) {
View vv = getChildAt(i);
if (vv == null) {
break;
}
int height = mItemHeightNormal;
int visibility = View.VISIBLE;
if (vv.equals(first)) {
// processing the item that is being dragged
if (mDragPos == mFirstDragPos) {
// hovering over the original location
visibility = View.INVISIBLE;
} else {
// not hovering over it
height = 1;
}
} else if (i == childnum) {
if (mDragPos < getCount() - 1) {
height = mItemHeightExpanded;
}
}
ViewGroup.LayoutParams params = vv.getLayoutParams();
params.height = height;
vv.setLayoutParams(params);
vv.setVisibility(visibility);
}
}
@Override
public boolean onTouchEvent(MotionEvent ev) {
if ((mDragListener != null || 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) {
if (mDragListener != null) {
mDragListener.drag(mDragPos, itemnum);
}
mDragPos = itemnum;
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);
}
private void startDragging(Bitmap bm, int x, int y) {
stopDragging();
mWindowParams = new WindowManager.LayoutParams();
mWindowParams.gravity = Gravity.TOP | Gravity.LEFT;
mWindowParams.x = x;
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
| WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS;
mWindowParams.format = PixelFormat.TRANSLUCENT;
mWindowParams.windowAnimations = 0;
Context context = getContext();
ImageView v = new ImageView(context);
int backGroundColor = context.getResources().getColor(android.R.color.holo_blue_dark);
v.setAlpha((float) 0.7);
v.setBackgroundColor(backGroundColor);
v.setImageBitmap(bm);
mDragBitmap = bm;
mWindowManager = (WindowManager) context.getSystemService("window");
mWindowManager.addView(v, mWindowParams);
mDragView = v;
}
private void dragView(int x, int y) {
mWindowParams.y = y - mDragPoint + mCoordOffset;
mWindowManager.updateViewLayout(mDragView, mWindowParams);
}
private void stopDragging() {
if (mDragView != null) {
mDragView.setVisibility(GONE);
WindowManager wm = (WindowManager) getContext().getSystemService("window");
wm.removeView(mDragView);
mDragView.setImageDrawable(null);
mDragView = null;
}
if (mDragBitmap != null) {
mDragBitmap.recycle();
mDragBitmap = null;
}
}
public void setDragListener(DragListener l) {
mDragListener = l;
}
public void setDropListener(DropListener l) {
mDropListener = l;
}
public interface DragListener {
void drag(int from, int to);
}
public interface DropListener {
void drop(int from, int to);
}
}