//TO DO:
//
// - improve timer performance (especially on Eee Pad)
// - improve child rearranging
package com.way.main;
import java.util.Collections;
import java.util.ArrayList;
import android.app.Activity;
import android.content.Context;
import android.graphics.Point;
import android.os.Handler;
import android.os.SystemClock;
import android.util.AttributeSet;
import android.util.DisplayMetrics;
import android.view.animation.AlphaAnimation;
import android.view.animation.Animation;
import android.view.animation.AnimationSet;
import android.view.animation.ScaleAnimation;
import android.view.animation.TranslateAnimation;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ImageView;
public class DraggableGridView extends ViewGroup implements View.OnTouchListener, View.OnClickListener, View.OnLongClickListener {
//layout vars
public static float childRatio = .9f;
protected int colCount, childSize, padding, dpi, scroll = 0;
protected float lastDelta = 0;
protected Handler handler = new Handler();
//dragging vars
protected int dragged = -1, lastX = -1, lastY = -1, lastTarget = -1;
protected boolean enabled = true, touching = false;
//anim vars
public static int animT = 150;
protected ArrayList<Integer> newPositions = new ArrayList<Integer>();
//listeners
protected OnRearrangeListener onRearrangeListener;
protected OnClickListener secondaryOnClickListener;
private OnItemClickListener onItemClickListener;
//Ronrey
protected OnTouchListener onTouchListener;
//CONSTRUCTOR AND HELPERS
public DraggableGridView (Context context, AttributeSet attrs) {
super(context, attrs);
setListeners();
handler.removeCallbacks(updateTask);
handler.postAtTime(updateTask, SystemClock.uptimeMillis() + 500);
setChildrenDrawingOrderEnabled(true);
DisplayMetrics metrics = new DisplayMetrics();
((Activity)context).getWindowManager().getDefaultDisplay().getMetrics(metrics);
dpi = metrics.densityDpi;
}
protected void setListeners()
{
setOnTouchListener(this);
super.setOnClickListener(this);
setOnLongClickListener(this);
}
@Override
public void setOnClickListener(OnClickListener l) {
secondaryOnClickListener = l;
}
protected Runnable updateTask = new Runnable() {
public void run()
{
if (dragged != -1)
{
if (lastY < padding * 3 && scroll > 0)
scroll -= 20;
else if (lastY > getBottom() - getTop() - (padding * 3) && scroll < getMaxScroll())
scroll += 20;
}
else if (lastDelta != 0 && !touching)
{
scroll += lastDelta;
lastDelta *= .9;
if (Math.abs(lastDelta) < .25)
lastDelta = 0;
}
clampScroll();
onLayout(true, getLeft(), getTop(), getRight(), getBottom());
handler.postDelayed(this, 25);
}
};
//OVERRIDES
@Override
public void addView(View child) {
super.addView(child);
newPositions.add(-1);
};
@Override
public void removeViewAt(int index) {
super.removeViewAt(index);
newPositions.remove(index);
};
//LAYOUT
@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
//compute width of view, in dp
float w = (r - l) / (dpi / 160f);
//determine number of columns, at least 2
colCount = 2;
int sub = 240;
w -= 280;
while (w > 0)
{
colCount++;
w -= sub;
sub += 40;
}
//determine childSize and padding, in px
childSize = (r - l) / colCount;
childSize = Math.round(childSize * childRatio);
padding = ((r - l) - (childSize * colCount)) / (colCount + 1);
for (int i = 0; i < getChildCount(); i++)
if (i != dragged)
{
Point xy = getCoorFromIndex(i);
getChildAt(i).layout(xy.x, xy.y, xy.x + childSize, xy.y + childSize);
}
}
@Override
protected int getChildDrawingOrder(int childCount, int i) {
if (dragged == -1)
return i;
else if (i == childCount - 1)
return dragged;
else if (i >= dragged)
return i + 1;
return i;
}
public int getIndexFromCoor(int x, int y)
{
int col = getColOrRowFromCoor(x), row = getColOrRowFromCoor(y + scroll);
if (col == -1 || row == -1) //touch is between columns or rows
return -1;
int index = row * colCount + col;
if (index >= getChildCount())
return -1;
return index;
}
protected int getColOrRowFromCoor(int coor)
{
coor -= padding;
for (int i = 0; coor > 0; i++)
{
if (coor < childSize)
return i;
coor -= (childSize + padding);
}
return -1;
}
protected int getTargetFromCoor(int x, int y)
{
if (getColOrRowFromCoor(y + scroll) == -1) //touch is between rows
return -1;
//if (getIndexFromCoor(x, y) != -1) //touch on top of another visual
//return -1;
int leftPos = getIndexFromCoor(x - (childSize / 4), y);
int rightPos = getIndexFromCoor(x + (childSize / 4), y);
if (leftPos == -1 && rightPos == -1) //touch is in the middle of nowhere
return -1;
if (leftPos == rightPos) //touch is in the middle of a visual
return -1;
int target = -1;
if (rightPos > -1)
target = rightPos;
else if (leftPos > -1)
target = leftPos + 1;
if (dragged < target)
return target - 1;
//Toast.makeText(getContext(), "Target: " + target + ".", Toast.LENGTH_SHORT).show();
return target;
}
protected Point getCoorFromIndex(int index)
{
int col = index % colCount;
int row = index / colCount;
return new Point(padding + (childSize + padding) * col,
padding + (childSize + padding) * row - scroll);
}
public int getIndexOf(View child)
{
for (int i = 0; i < getChildCount(); i++)
if (getChildAt(i) == child)
return i;
return -1;
}
//EVENT HANDLERS
public void onClick(View view) {
if (enabled)
{
if (secondaryOnClickListener != null)
secondaryOnClickListener.onClick(view);
if (onItemClickListener != null && getLastIndex() != -1)
onItemClickListener.onItemClick(null, getChildAt(getLastIndex()), getLastIndex(), getLastIndex() / colCount);
}
}
public boolean onLongClick(View view)
{
if (!enabled)
return false;
int index = getLastIndex();
if (index != -1)
{
dragged = index;
animateDragged();
return true;
}
return false;
}
public boolean onTouch(View view, MotionEvent event)
{
int action = event.getAction();
switch (action & MotionEvent.ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
enabled = true;
lastX = (int) event.getX();
lastY = (int) event.getY();
touching = true;
break;
case MotionEvent.ACTION_MOVE:
int delta = lastY - (int)event.getY();
if (dragged != -1)
{
//change draw location of dragged visual
int x = (int)event.getX(), y = (int)event.getY();
int l = x - (3 * childSize / 4), t = y - (3 * childSize / 4);
getChildAt(dragged).layout(l, t, l + (childSize * 3 / 2), t + (childSize * 3 / 2));
//check for new target hover
int target = getTargetFromCoor(x, y);
if (lastTarget != target)
{
if (target != -1)
{
animateGap(target);
lastTarget = target;
}
}
}
else
{
scroll += delta;
clampScroll();
if (Math.abs(delta) > 2)
enabled = false;
onLayout(true, getLeft(), getTop(), getRight(), getBottom());
}
lastX = (int) event.getX();
lastY = (int) event.getY();
lastDelta = delta;
break;
case MotionEvent.ACTION_UP:
if (dragged != -1)
{
View v = getChildAt(dragged);
if (lastTarget != -1)
reorderChildren();
else
{
Point xy = getCoorFromIndex(dragged);
v.layout(xy.x, xy.y, xy.x + childSize, xy.y + childSize);
}
v.clearAnimation();
if (v instanceof ImageView)
((ImageView)v).setAlpha(255);
lastTarget = -1;
dragged = -1;
}
touching = false;
break;
}
if (dragged != -1)
return true;
return false;
}
//EVENT HELPERS
protected void animateDragged()
{
View v = getChildAt(dragged);
int x = getCoorFromIndex(dragged).x + childSize / 2, y = getCoorFromIndex(dragged).y + childSize / 2;
int l = x - (3 * childSize / 4), t = y - (3 * childSize / 4);
v.layout(l, t, l + (childSize * 3 / 2), t + (childSize * 3 / 2));
AnimationSet animSet = new AnimationSet(true);
ScaleAnimation scale = new ScaleAnimation(.667f, 1, .667f, 1, childSize * 3 / 4, childSize * 3 / 4);
scale.setDuration(animT);
AlphaAnimation alpha = new AlphaAnimation(1, .5f);
alpha.setDuration(animT);
animSet.addAnimation(scale);
animSet.addAnimation(alpha);
animSet.setFillEnabled(true);
animSet.setFillAfter(true);
v.clearAnimation();
v.startAnimation(animSet);
}
protected void animateGap(int target)
{
for (int i = 0; i < getChildCount(); i++)
{
View v = getChildAt(i);
if (i == dragged)
continue;
int newPos = i;
if (dragged < target && i >= dragged + 1 && i <= target)
newPos--;
else if (target < dragged && i >= target && i < dragged)
newPos++;
//animate
int oldPos = i;
if (newPositions.get(i) != -1)
oldPos = newPositions.get(i);
if (oldPos == newPos)
continue;
Point oldXY = getCoorFromIndex(oldPos);
Point newXY = getCoorFromIndex(newPos);
Point oldOffset = new Point(oldXY.x - v.getLeft(), oldXY.y - v.getTop());
Point newOffset = new Point(newXY.x - v.getLeft(), newXY.y - v.getTop());
TranslateAnimation translate = new TranslateAnimation(Animation.ABSOLUTE, oldOffset.x,
Animation.ABSOLUTE, newOffset.x,
Animation.ABSOLUTE, oldOffset.y,
Animation.ABSOLUTE, newOffset.y);
translate.setDuration(animT);
translate.setFillEnabled(true);
translate.setFillAfter(true);
v.clearAnimation();
v.startAnimation(translate);
newPositions.set(i, newPos);
}
}
protected void reorderChildren()
{
//FIGURE OUT HOW TO REORDER CHILDREN WITHOUT REMOVING THEM ALL AND RECONSTRUCTING THE LIST!!!
if (onRearrangeListener != null)
onRearrangeListener.onRearrange(dragged, lastTarget);
ArrayList<View> children = new ArrayList<View>();
for (int i = 0; i < getChildCount(); i++)
{
getChildAt(i).clearAnimation();
children.add(getChildAt(i));
}
removeAllViews();
while (dragged != lastTarget)
if (lastTarget == children.size()) // dragged and dropped to the right of the last element
{
children.add(children.remove(dragged));
dragged = lastTarget;
}
else if (dragged < lastTarget) // shift to the right
{
Collections.swap(children, dragged, dragged + 1);
dragged++;
}
else if (dragged > lastTarget) // shift to the left
{
Collections.swap(children, dragged, dragged - 1);
dragged--;
}
for (int i = 0; i < children.size(); i++)
{
newPositions.set(i, -1);
addView(children.get(i));
}
onLayout(true, getLeft(), getTop(), getRight(), getBottom());
}
public void scrollToTop()
{
scroll = 0;
}
public void scrollToBottom()
{
scroll = Integer.MAX_VALUE;
clampScroll();
}
protected void clampScroll()
{
int stretch = 3, overreach = getHeight() / 2;
int max = getMaxScroll();
max = Math.max(max, 0);
if (scroll < -overreach)
{
scroll = -overreach;
lastDelta = 0;
}
else if (scroll > max + overreach)
{
scroll = max + overreach;
lastDelta = 0;
}
else if (scroll < 0)
{
if (scroll >= -stretch)
scroll = 0;
else if (!touching)
scroll -= scroll / stretch;
}
else if (scroll > max)
{
if (scroll <= max + stretch)
scroll = max;
else if (!touching)
scroll += (max - scroll) / stretch;
}
}
protected int getMaxScroll()
{
int rowCount = (int)Math.ceil((double)getChildCount()/colCount), max = rowCount * childSize + (rowCount + 1) * padding - getHeight();
return max;
}
public int getLastIndex()
{
return getIndexFromCoor(lastX, lastY);
}
//OTHER METHODS
public void setOnRearrangeListener(OnRearrangeListener l)
{
this.onRearrangeListener = l;
}
public void setOnItemClickListener(OnItemClickListener l)
{
this.onItemClickListener = l;
}
}
最近下载更多
最近浏览更多
