自定义的窗帘效果

package com.example.curtaineffect.view;


import android.view.View.OnTouchListener;
import com.example.curtaineffect.R;
import com.example.curtaineffect.tools.BaseTools;


import android.R.integer;
import android.content.Context;
import android.graphics.Color;
import android.util.AttributeSet;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.animation.BounceInterpolator;
import android.view.animation.Interpolator;
import android.widget.ImageView;
import android.widget.RelativeLayout;
import android.widget.Scroller;
/**
 * 窗帘拉开自定义布局
 * @author Ra
 * blog : http://blog.csdn.net/vipzjyno1/
 */
public class CurtainView extends RelativeLayout implements OnTouchListener{
private static String TAG = "CurtainView";
private Context mContext;
/** Scroller 拖动类 */
private Scroller mScroller;
/** 屏幕高度  */
private int mScreenHeigh = 0;
/** 屏幕宽度  */
private int mScreenWidth = 0;
/** 点击时候Y的坐标*/
private int downY = 0;
/** 拖动时候Y的坐标*/
private int moveY = 0;
/** 拖动时候Y的方向距离*/
private int scrollY = 0;
/** 松开时候Y的坐标*/
private int upY = 0;
/** 广告幕布的高度*/
private int curtainHeigh = 0;
/** 是否 打开*/
private boolean isOpen = false;
/** 是否在动画 */
private boolean isMove = false;
/** 绳子的图片*/
private ImageView img_curtain_rope;
/** 广告的图片*/
private ImageView img_curtain_ad;
/** 上升动画时间 */
private int upDuration = 1000;
/** 下落动画时间 */
private int downDuration = 500;


public CurtainView(Context context,MyListener listener) {
super(context);

init(context);


}


public CurtainView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(context);
}


public CurtainView(Context context, AttributeSet attrs) {
super(context, attrs);
init(context);
}
/** 初始化 */
private void init(Context context) {
this.mContext = context;
//Interpolator 设置为有反弹效果的  （Bounce：反弹）
Interpolator interpolator = new BounceInterpolator();
mScroller = new Scroller(context, interpolator);
mScreenHeigh = BaseTools.getWindowHeigh(context);
mScreenWidth = BaseTools.getWindowWidth(context);
// 背景设置成透明
this.setBackgroundColor(Color.argb(0, 0, 0, 0));
final View view = LayoutInflater.from(mContext).inflate(R.layout.curtain, null);
img_curtain_ad = (ImageView)view.findViewById(R.id.img_curtain_ad);
img_curtain_rope = (ImageView)view.findViewById(R.id.img_curtain_rope);
addView(view);
img_curtain_ad.post(new Runnable() {

@Override
public void run() {
// TODO Auto-generated method stub
curtainHeigh  = img_curtain_ad.getHeight();
Log.d(TAG, "curtainHeigh= " + curtainHeigh);
CurtainView.this.scrollTo(0, curtainHeigh);

//注意scrollBy和scrollTo的区别
}
});
img_curtain_rope.setOnTouchListener(this);
}


/**
* 拖动动画
* @param startY  
* @param dy  垂直距离, 滚动的y距离
* @param duration 时间
*/
public void startMoveAnim(int startY, int dy, int duration) {
isMove = true;
mScroller.startScroll(0, startY, 0, dy, duration);
invalidate();//通知UI线程的更新
}

@Override
protected void onLayout(boolean changed, int l, int t, int r, int b) {
// TODO Auto-generated method stub
super.onLayout(changed, l, t, r, b);
}

@Override
public void computeScroll() {
//判断是否还在滚动，还在滚动为true
if (mScroller.computeScrollOffset()) {
scrollTo(mScroller.getCurrX(), mScroller.getCurrY());
//更新界面
postInvalidate();
isMove = true;
} else {
isMove = false;
}
super.computeScroll();
}


@Override
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
if (!isMove) {

int a = 0;
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
downY = (int) event.getRawY();
return true;
case MotionEvent.ACTION_MOVE:
moveY = (int) event.getRawY();
scrollY = moveY - downY;

if (scrollY < 0) {
// 向上滑动
if(isOpen){
if(Math.abs(scrollY) <= img_curtain_ad.getBottom()){
scrollTo(0, -scrollY);
}
}
} else {
// 向下滑动
if(!isOpen){
if (scrollY <= curtainHeigh) {
scrollTo(0, curtainHeigh - scrollY);
System.out.println("scrollY:"+scrollY+" height:"+curtainHeigh+" 值："+(curtainHeigh - scrollY));
}else {
System.out.println("scrollY:"+scrollY);
}
}
}
break;
case MotionEvent.ACTION_UP:
upY = (int) event.getRawY();
if(Math.abs(upY - downY) < 10){
onRopeClick();
break;
}
if (downY > upY) {
// 向上滑动
if(isOpen){
if (Math.abs(scrollY) > curtainHeigh / 2) {
// 向上滑动超过半个屏幕高的时候 开启向上消失动画
startMoveAnim(this.getScrollY(),
(curtainHeigh - this.getScrollY()), upDuration);
isOpen = false;
} else {
startMoveAnim(this.getScrollY(), -this.getScrollY(),upDuration);
isOpen = true;
}
}
} else {
// 向下滑动
if (scrollY > curtainHeigh / 2) {
// 向上滑动超过半个屏幕高的时候 开启向上消失动画
startMoveAnim(this.getScrollY(), -this.getScrollY(),upDuration);
isOpen = true;
} else {
startMoveAnim(this.getScrollY(),(curtainHeigh - this.getScrollY()), upDuration);
isOpen = false;
}
}
break;
default:
break;
}
}
return false;
}
/**
* 点击绳索开关，会展开关闭
* 在onToch中使用这个中的方法来当点击事件，避免了点击时候响应onTouch的衔接不完美的影响
*/
public void onRopeClick(){
if(isOpen){
CurtainView.this.startMoveAnim(0, curtainHeigh, upDuration);
}else{
CurtainView.this.startMoveAnim(curtainHeigh,-curtainHeigh, downDuration);
}
isOpen = !isOpen;
}
}