7.侧滑、ViewDragHelper、属性动画

实现这样的效果：

## 侧滑面板（对ViewGroup的自定义）
* 应用场景: 扩展主面板的功能
* 功能实现:
> 1. ViewDragHelper: Google2013年IO大会提出的,
>  解决界面控件拖拽移动问题. (v4包下)
> 2. mTouchSlop 最小敏感范围, 值越小, 越敏感

* 伴随动画:
> 1. 左面板: 缩放动画, 平移动画, 透明度动画
> 2. 主面板: 缩放动画
> 3. 背景动画: 亮度变化 (颜色变化)

* 状态监听\触摸优化:
> 1. 设置并更新状态
> 2. 触摸优化: 重写ViewGroup里onInterceptTouchEvent和onTouchEvent

新v4、看大小
nineoldandroids.jar  属性动画，兼容9个低版本
ActionBarSherlock 

 

 

布局：

1.  

   <com.drag.DragLayout xmlns:android="http://schemas.android.com/apk/res/android"
       xmlns:tools="http://schemas.android.com/tools"
       android:id="@+id/dl"
       android:layout_width="match_parent"
       android:layout_height="match_parent"
       android:background="@drawable/bg"
       tools:context=".MainActivity" >
       <LinearLayout
           android:layout_width="match_parent"
           android:layout_height="match_parent"
           android:orientation="vertical"
           android:paddingBottom="50dp"
           android:paddingLeft="10dp"
           android:paddingRight="50dp"
           android:paddingTop="50dp" >
           <ImageView
               android:layout_width="50dp"
               android:layout_height="50dp"
               android:src="@drawable/head" />
           <ListView
               android:id="@+id/lv_left"
               android:layout_width="match_parent"
               android:layout_height="match_parent" >
           </ListView>
       </LinearLayout>
       <com.drag.MyLinearLayout
           android:id="@+id/mll"
           android:layout_width="match_parent"
           android:layout_height="match_parent"
           android:background="#ffffff"
           android:orientation="vertical" >
           <RelativeLayout
               android:layout_width="match_parent"
               android:layout_height="50dp"
               android:background="#18B6EF"
               android:gravity="center_vertical" >
               <ImageView
                   android:id="@+id/iv_header"
                   android:layout_width="30dp"
                   android:layout_height="30dp"
                   android:layout_marginLeft="15dp"
                   android:src="@drawable/head" />
               <TextView
                   android:layout_width="wrap_content"
                   android:layout_height="wrap_content"
                   android:layout_centerHorizontal="true"
                   android:text="Header" />
           </RelativeLayout>
           <ListView
               android:id="@+id/lv_main"
               android:layout_width="match_parent"
               android:layout_height="match_parent" >
           </ListView>
       </com.drag.MyLinearLayout>
   </com.drag.DragLayout>
   

   　　Utils：单例的toast

2. public class Utils {
   	public static Toast mToast;
   	public static void showToast(Context mContext, String msg) {
   		if (mToast == null) {
   			mToast = Toast.makeText(mContext, "", Toast.LENGTH_SHORT);
   		}
   		mToast.setText(msg);
   		mToast.show();
   	}
   
   	/**
   	 * dip 转换成 px
   	 * @param dip
   	 * @param context
   	 * @return
   	 */
   	public static float dip2Dimension(float dip, Context context) {
   		DisplayMetrics displayMetrics = context.getResources().getDisplayMetrics();
   		return TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dip, displayMetrics);
   	}
   	/**
   	 * @param dip
   	 * @param context
   	 * @param complexUnit {@link TypedValue#COMPLEX_UNIT_DIP} {@link TypedValue#COMPLEX_UNIT_SP}}
   	 * @return
   	 */
   	public static float toDimension(float dip, Context context, int complexUnit) {
   		DisplayMetrics displayMetrics = context.getResources().getDisplayMetrics();
   		return TypedValue.applyDimension(complexUnit, dip, displayMetrics);
   	}
   	/** 获取状态栏高度
   	 * @param v
   	 * @return
   	 */
   	public static int getStatusBarHeight(View v) {
   		if (v == null) {
   			return 0;
   		}
   		Rect frame = new Rect();
   		v.getWindowVisibleDisplayFrame(frame);
   		return frame.top;
   	}
   	public static String getActionName(MotionEvent event) {
   		String action = "unknow";
   		switch (MotionEventCompat.getActionMasked(event)) {
   		case MotionEvent.ACTION_DOWN:
   			action = "ACTION_DOWN";
   			break;
   		case MotionEvent.ACTION_MOVE:
   			action = "ACTION_MOVE";
   			break;
   		case MotionEvent.ACTION_UP:
   			action = "ACTION_UP";
   			break;
   		case MotionEvent.ACTION_CANCEL:
   			action = "ACTION_CANCEL";
   			break;
   		case MotionEvent.ACTION_SCROLL:
   			action = "ACTION_SCROLL";
   			break;
   		case MotionEvent.ACTION_OUTSIDE:
   			action = "ACTION_SCROLL";
   			break;
   		default:
   			break;
   		}
   		return action;
   	}
   }
   

   　　DragLayout：

3. /**
    * 侧滑面板
    * @author poplar
    *
    */
   public class DragLayout extends FrameLayout {
   	private static final String TAG = "TAG";
   	private ViewDragHelper mDragHelper;
   	private ViewGroup mLeftContent;
   	private ViewGroup mMainContent;
   	private OnDragStatusChangeListener mListener;
   	private Status mStatus = Status.Close;
   
   	/**
   	 * 状态枚举
   	 */
   	public static enum Status {
   		Close, Open, Draging;
   	}
   	public interface OnDragStatusChangeListener{
   		void onClose();
   		void onOpen();
   		void onDraging(float percent);
   	}
   
   	public Status getStatus() {
   		return mStatus;
   	}
   	public void setStatus(Status mStatus) {
   		this.mStatus = mStatus;
   	}
   	public void setDragStatusListener(OnDragStatusChangeListener mListener){
   		this.mListener = mListener;
   	}
   
   	public DragLayout(Context context) {
   		this(context, null);
   	}
   	public DragLayout(Context context, AttributeSet attrs) {
   		this(context, attrs, 0);
   	}
   	public DragLayout(Context context, AttributeSet attrs, int defStyle) {
   		super(context, attrs, defStyle);
   
   		// a.初始化 (通过静态方法)
   		mDragHelper = ViewDragHelper.create(this , mCallback);
   
   	}
   
   	ViewDragHelper.Callback mCallback = new ViewDragHelper.Callback() {
   		// c. 重写事件
   
   		// 1. 根据返回结果决定当前child是否可以拖拽
   		// child 当前被拖拽的View
   		// pointerId 区分多点触摸的id
   		@Override
   		public boolean tryCaptureView(View child, int pointerId) {
   			Log.d(TAG, "tryCaptureView: " + child);
   			return true;
   		};
   
   		@Override
   		public void onViewCaptured(View capturedChild, int activePointerId) {
   			Log.d(TAG, "onViewCaptured: " + capturedChild);
   			// 当capturedChild被捕获时,调用.
   			super.onViewCaptured(capturedChild, activePointerId);
   		}
   		@Override
   		public int getViewHorizontalDragRange(View child) {
   			// 返回拖拽的范围, 不对拖拽进行真正的限制. 仅仅决定了动画执行速度
   			return mRange;
   		}
   
   		// 2. 根据建议值 修正将要移动到的(横向)位置   (重要)
   		// 此时没有发生真正的移动
   		public int clampViewPositionHorizontal(View child, int left, int dx) {
   			// child: 当前拖拽的View
   			// left 新的位置的建议值, dx 位置变化量
   			// left = oldLeft + dx;
   			Log.d(TAG, "clampViewPositionHorizontal: "
   					+ "oldLeft: " + child.getLeft() + " dx: " + dx + " left: " +left);
   
   			if(child == mMainContent){
   				left = fixLeft(left);
   			}
   			return left;
   		}
   		// 3. 当View位置改变的时候, 处理要做的事情 (更新状态, 伴随动画, 重绘界面)
   		// 此时,View已经发生了位置的改变
   		@Override
   		public void onViewPositionChanged(View changedView, int left, int top,
   				int dx, int dy) {
   			// changedView 改变位置的View
   			// left 新的左边值
   			// dx 水平方向变化量
   			super.onViewPositionChanged(changedView, left, top, dx, dy);
   			Log.d(TAG, "onViewPositionChanged: " + "left: " + left + " dx: " + dx);
   
   			int newLeft = left;
   			if(changedView == mLeftContent){
   				// 把当前变化量传递给mMainContent
   				newLeft = mMainContent.getLeft() + dx;
   			}
   
   			// 进行修正
   			newLeft = fixLeft(newLeft);
   
   			if(changedView == mLeftContent) {
   				// 当左面板移动之后, 再强制放回去.
   				mLeftContent.layout(0, 0, 0 + mWidth, 0 + mHeight);
   				mMainContent.layout(newLeft, 0, newLeft + mWidth, 0 + mHeight);
   			}
   			// 更新状态,执行动画
   			dispatchDragEvent(newLeft);
   
   			// 为了兼容低版本, 每次修改值之后, 进行重绘
   			invalidate();
   		}
   		// 4. 当View被释放的时候, 处理的事情(执行动画)
   		@Override
   		public void onViewReleased(View releasedChild, float xvel, float yvel) {
   			// View releasedChild 被释放的子View
   			// float xvel 水平方向的速度, 向右为+
   			// float yvel 竖直方向的速度, 向下为+
   			Log.d(TAG, "onViewReleased: " + "xvel: " + xvel + " yvel: " + yvel);
   			super.onViewReleased(releasedChild, xvel, yvel);
   
   			// 判断执行 关闭/开启
   			// 先考虑所有开启的情况,剩下的就都是关闭的情况
   			if(xvel == 0 && mMainContent.getLeft() > mRange / 2.0f){
   				open();
   			}else if (xvel > 0) {
   				open();
   			}else {
   				close();
   			}
   
   		}
   		@Override
   		public void onViewDragStateChanged(int state) {
   			// TODO Auto-generated method stub
   			super.onViewDragStateChanged(state);
   		}
   	};
   
   	/**
   	 * 根据范围修正左边值
   	 * @param left
   	 * @return
   	 */
   	private int fixLeft(int left) {
   		if(left < 0){
   			return 0;
   		}else if (left > mRange) {
   			return mRange;
   		}
   		return left;
   	}
   
   	protected void dispatchDragEvent(int newLeft) {
   		float percent = newLeft * 1.0f/ mRange;
   		//0.0f -> 1.0f
   		Log.d(TAG, "percent: " + percent);
   
   		if(mListener != null){
   			mListener.onDraging(percent);
   		}
   
   		// 更新状态, 执行回调
   		Status preStatus = mStatus;
   		mStatus = updateStatus(percent);
   		if(mStatus != preStatus){
   			// 状态发生变化
   			if(mStatus == Status.Close){
   				// 当前变为关闭状态
   				if(mListener != null){
   					mListener.onClose();
   				}
   			}else if (mStatus == Status.Open) {
   				if(mListener != null){
   					mListener.onOpen();
   				}
   			}
   		}
   
   //		* 伴随动画:
   		animViews(percent);
   
   	}
   	private Status updateStatus(float percent) {
   		if(percent == 0f){
   			return Status.Close;
   		}else if (percent == 1.0f) {
   			return Status.Open;
   		}
   		return Status.Draging;
   	}
   	private void animViews(float percent) {
   		//		> 1. 左面板: 缩放动画, 平移动画, 透明度动画
   					// 缩放动画 0.0 -> 1.0 >>> 0.5f -> 1.0f  >>> 0.5f * percent + 0.5f
   			//		mLeftContent.setScaleX(0.5f + 0.5f * percent);
   			//		mLeftContent.setScaleY(0.5f + 0.5f * percent);
   					ViewHelper.setScaleX(mLeftContent, evaluate(percent, 0.5f, 1.0f));
   					ViewHelper.setScaleY(mLeftContent, 0.5f + 0.5f * percent);
   					// 平移动画: -mWidth / 2.0f -> 0.0f
   					ViewHelper.setTranslationX(mLeftContent, evaluate(percent, -mWidth / 2.0f, 0));
   					// 透明度: 0.5 -> 1.0f
   					ViewHelper.setAlpha(mLeftContent, evaluate(percent, 0.5f, 1.0f));
   
   		//		> 2. 主面板: 缩放动画
   					// 1.0f -> 0.8f
   					ViewHelper.setScaleX(mMainContent, evaluate(percent, 1.0f, 0.8f));
   					ViewHelper.setScaleY(mMainContent, evaluate(percent, 1.0f, 0.8f));
   
   		//		> 3. 背景动画: 亮度变化 (颜色变化)
   					getBackground().setColorFilter((Integer)evaluateColor(percent, Color.BLACK, Color.TRANSPARENT), Mode.SRC_OVER);
   	}
   
       /**
        * 估值器，0-100,一半50百分之=50,10-100
        * @param fraction
        * @param startValue
        * @param endValue
        * @return
        */
       public Float evaluate(float fraction, Number startValue, Number endValue) {
           float startFloat = startValue.floatValue();
           return startFloat + fraction * (endValue.floatValue() - startFloat);
       }
       /**
        * 颜色变化过度
        * @param fraction
        * @param startValue
        * @param endValue
        * @return
        */
       public Object evaluateColor(float fraction, Object startValue, Object endValue) {
           int startInt = (Integer) startValue;
           int startA = (startInt >> 24) & 0xff;
           int startR = (startInt >> 16) & 0xff;
           int startG = (startInt >> 8) & 0xff;
           int startB = startInt & 0xff;
           int endInt = (Integer) endValue;
           int endA = (endInt >> 24) & 0xff;
           int endR = (endInt >> 16) & 0xff;
           int endG = (endInt >> 8) & 0xff;
           int endB = endInt & 0xff;
           return (int)((startA + (int)(fraction * (endA - startA))) << 24) |
                   (int)((startR + (int)(fraction * (endR - startR))) << 16) |
                   (int)((startG + (int)(fraction * (endG - startG))) << 8) |
                   (int)((startB + (int)(fraction * (endB - startB))));
       }
   	@Override
   	public void computeScroll() {
   		super.computeScroll();
   
   		// 2. 持续平滑动画 (高频率调用)
   		if(mDragHelper.continueSettling(true)){
   			//  如果返回true, 动画还需要继续执行
   			ViewCompat.postInvalidateOnAnimation(this);
   		}
   	}
   
   	public void close(){
   		close(true);
   	}
   	/**
   	 * 关闭
   	 */
   	public void close(boolean isSmooth) {
   		int finalLeft = 0;
   		if(isSmooth){
   			// 1. 触发一个平滑动画
   			if(mDragHelper.smoothSlideViewTo(mMainContent, finalLeft, 0)){
   				// 返回true代表还没有移动到指定位置, 需要刷新界面.
   				// 参数传this(child所在的ViewGroup)
   				ViewCompat.postInvalidateOnAnimation(this);
   			}
   		}else {
   			mMainContent.layout(finalLeft, 0, finalLeft + mWidth, 0 + mHeight);
   		}
   	}
   
   	public void open(){
   		open(true);
   	}
   	/**
   	 * 开启
   	 */
   	public void open(boolean isSmooth) {
   		int finalLeft = mRange;
   		if(isSmooth){
   			// 1. 触发一个平滑动画
   			if(mDragHelper.smoothSlideViewTo(mMainContent, finalLeft, 0)){
   				// 返回true代表还没有移动到指定位置, 需要刷新界面.
   				// 参数传this(child所在的ViewGroup)
   				ViewCompat.postInvalidateOnAnimation(this);
   			}
   		}else {
   			mMainContent.layout(finalLeft, 0, finalLeft + mWidth, 0 + mHeight);
   		}
   	}
   	private int mHeight;
   	private int mWidth;
   	private int mRange;
   
   	// b.传递触摸事件
   	@Override
   	public boolean onInterceptTouchEvent(MotionEvent ev) {
   		// 传递给mDragHelper
   		return mDragHelper.shouldInterceptTouchEvent(ev);
   	}
   	@Override
   	public boolean onTouchEvent(MotionEvent event) {
   		try {
   			mDragHelper.processTouchEvent(event);
   		} catch (Exception e) {
   			e.printStackTrace();
   		}
   		// 返回true, 持续接受事件
   		return true;
   	}
   
   	@Override
   	protected void onFinishInflate() {
   		super.onFinishInflate();
   		// Github
   		// 写注释
   		// 容错性检查 (至少有俩子View, 子View必须是ViewGroup的子类)
   
   		if(getChildCount() < 2){
   			throw new IllegalStateException("布局至少有俩孩子. Your ViewGroup must have 2 children at least.");
   		}
   		if(!(getChildAt(0) instanceof ViewGroup && getChildAt(1) instanceof ViewGroup)){
   			throw new IllegalArgumentException("子View必须是ViewGroup的子类. Your children must be an instance of ViewGroup");
   		}
   
   		mLeftContent = (ViewGroup) getChildAt(0);
   		mMainContent = (ViewGroup) getChildAt(1);
   	}
   
   	@Override
   	protected void onSizeChanged(int w, int h, int oldw, int oldh) {
   		super.onSizeChanged(w, h, oldw, oldh);
   		// 当尺寸有变化的时候调用
   
   		mHeight = getMeasuredHeight();
   		mWidth = getMeasuredWidth();
   
   		// 移动的范围
   		mRange = (int) (mWidth * 0.6f);
   
   	}
   
   }
   

   　　MyLinearLayout：主页面，在打开侧边栏或者拖拽时不让主页面里的listview滑动

4. public class MyLinearLayout extends LinearLayout {
   	private DragLayout mDragLayout;
   	public MyLinearLayout(Context context) {
   		super(context);
   	}
   	public MyLinearLayout(Context context, AttributeSet attrs) {
   		super(context, attrs);
   	}
   
   	public void setDraglayout(DragLayout mDragLayout){
   		this.mDragLayout = mDragLayout;
   	}
   
   	@Override
   	public boolean onInterceptTouchEvent(MotionEvent ev) {
   		// 如果当前是关闭状态, 按之前方法判断
   		if(mDragLayout.getStatus() == Status.Close){
   			return super.onInterceptTouchEvent(ev);
   		}else {
   			return true;
   		}
   	}
   
   	@Override
   	public boolean onTouchEvent(MotionEvent event) {
   		// 如果当前是关闭状态, 按之前方法处理
   		if(mDragLayout.getStatus() == Status.Close){
   			return super.onTouchEvent(event);
   		}else {
   			// 手指抬起, 执行关闭操作
   			if(event.getAction() == MotionEvent.ACTION_UP){
   				mDragLayout.close();
   			}
   
   			return true;
   		}
   	}
   }
   

   　　MainActivity

5. public class MainActivity extends Activity {
   	private static final String TAG = "TAG";
   	@Override
   	protected void onCreate(Bundle savedInstanceState) {
   		super.onCreate(savedInstanceState);
   		requestWindowFeature(Window.FEATURE_NO_TITLE);
   		setContentView(R.layout.activity_main);
   
   		final ListView mLeftList = (ListView) findViewById(R.id.lv_left);
   		final ListView mMainList = (ListView) findViewById(R.id.lv_main);
   		final ImageView mHeaderImage = (ImageView) findViewById(R.id.iv_header);
   		MyLinearLayout mLinearLayout = (MyLinearLayout) findViewById(R.id.mll);
   
   		// 查找Draglayout, 设置监听
   		DragLayout mDragLayout = (DragLayout) findViewById(R.id.dl);
   		// 设置引用
   		mLinearLayout.setDraglayout(mDragLayout);
   
   		mDragLayout.setDragStatusListener(new OnDragStatusChangeListener() {
   
   			@Override
   			public void onOpen() {
   				Utils.showToast(MainActivity.this, "onOpen");
   				// 左面板ListView随机设置一个条目
   				Random random = new Random();
   
   				int nextInt = random.nextInt(50);
   				mLeftList.smoothScrollToPosition(nextInt);
   
   			}
   
   			@Override
   			public void onDraging(float percent) {
   				Log.d(TAG, "onDraging: " + percent);// 0 -> 1
   				// 更新图标的透明度
   				// 1.0 -> 0.0
   				ViewHelper.setAlpha(mHeaderImage, 1 - percent);
   			}
   
   			@Override
   			public void onClose() {
   				Utils.showToast(MainActivity.this, "onClose");
   				// 让图标晃动
   //				mHeaderImage.setTranslationX(translationX)
   				ObjectAnimator mAnim = ObjectAnimator.ofFloat(mHeaderImage, "translationX", 15.0f);
   				mAnim.setInterpolator(new CycleInterpolator(4));
   				mAnim.setDuration(500);
   				mAnim.start();
   			}
   		});
   
   		mLeftList.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, Cheeses.sCheeseStrings){//Cheeses自己定义的，存放的一些字符串
   			@Override
   			public View getView(int position, View convertView, ViewGroup parent) {
   				View view = super.getView(position, convertView, parent);
   				TextView mText = ((TextView)view);
   				mText.setTextColor(Color.WHITE);
   				return view;
   			}
   		});
   
   		mMainList.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, Cheeses.NAMES));
   
   	}
   }