Android基于ViewDragHelper仿QQ5.0侧滑界面效果

public class SlidingMenu extends FrameLayout { private ViewDragHelper mViewDragHelper; private int mHeight;// 当前控件的高度 private int mWidhth;// 当前控件的宽度 private int mRange; // 菜单移动的距离 private ViewGroup mMenu;// 菜单内容 private ViewGroup mContent; // 主页面内容 private boolean isOpen = false;// 判断是否打开菜单 public SlidingMenu(Context context) { this(context, null); } public SlidingMenu(Context context, AttributeSet attrs) { this(context, attrs, 0); } public SlidingMenu(Context context, AttributeSet attrs, int defStyleAttr) { super(context, attrs, defStyleAttr); // 初始化ViewDragHelper mViewDragHelper = ViewDragHelper.create(this, callback); }}

<?xml version="1.0" encoding="utf-8"?><com.yitong.myslidingmenu2.view.SlidingMenu xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:id="@+id/main_slidingMenu" android:layout_width="match_parent" android:layout_height="match_parent" android:background="@mipmap/bg" android:orientation="horizontal" tools:context="com.yitong.myslidingmenu2.MainActivity"> <include layout="@layout/left_menu"/> <LinearLayout android:id="@+id/main_content" android:layout_width="match_parent" android:layout_height="match_parent" android:background="@mipmap/qq" android:orientation="horizontal"> <Button  android:layout_width="wrap_content"  android:layout_height="wrap_content"  android:onClick="click"  android:text="切换菜单"/> </LinearLayout></com.yitong.myslidingmenu2.view.SlidingMenu>

@Overrideprotected void onFinishInflate() { super.onFinishInflate(); if (getChildCount() < 2) {  throw new IllegalStateException("使用SlidingMenu中必须包含两个View"); } if (!(getChildAt(0) instanceof ViewGroup && getChildAt(1) instanceof ViewGroup)) {  throw new IllegalStateException("子View必须是ViewGroup的子类"); } mMenu = (ViewGroup) getChildAt(0); mContent = (ViewGroup) getChildAt(1); } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); mHeight = getMeasuredHeight(); mWidhth = getMeasuredWidth(); mRange = (int) (mWidhth * 0.8); }

@Overridepublic boolean onInterceptHoverEvent(MotionEvent event) { // 把触摸事件传递给ViewDragHelper return mViewDragHelper.shouldInterceptTouchEvent(event);}@Overridepublic boolean onTouchEvent(MotionEvent event) { try { mViewDragHelper.processTouchEvent(event);// 让ViewDrageHelper处理触摸事件 } catch (Exception e) { e.printStackTrace(); } return true;}

private Callback callback = new Callback() { @Override public boolean tryCaptureView(View child, int pointerId) { return true;// child：当前被拖拽的view.返回true表示当前view可以被拖拽 } @Override public int getViewHorizontalDragRange(View child) { return mRange;// 返回拖拽的距离，并不对拖拽进行限制，决定了动画的执行速度 } @Override public int clampViewPositionHorizontal(View child, int left, int dx) { // 根据建议值，修订水平方向移动的距离 if (child == mContent) { // ①滑动主页面内容，当超过屏幕预留宽度时，不再滑动。②向左滑动不能为负  left = fixContentSlidRange(left); } return left; } @Override public void onViewPositionChanged(View changedView, int left, int top, int dx, int dy) {// 当View的位置改变时调用，可以在此方法中添加一些View特效 super.onViewPositionChanged(changedView, left, top, dx, dy); // 当我们滑动菜单内容时，保持菜单内容不动，转化为主页面内容移动 int moveContentLeft = left;// 主页面内容左边的距离 if (changedView == mMenu) {  moveContentLeft = mContent.getLeft() + left;  mMenu.layout(0, 0, mMenu.getHeight(), mMenu.getHeight());// 强制菜单不移动 } moveContentLeft = fixContentSlidRange(moveContentLeft); mContent.layout(moveContentLeft, 0, moveContentLeft + mContent.getWidth(), mContent.getHeight()); animShow(moveContentLeft);// 菜单打开时，一些动画 invalidate();// 重绘界面，兼容低版本 } @Override public void onViewReleased(View releasedChild, float xvel, float yvel) {// 当view松手时触发，处理自动平滑动画 super.onViewReleased(releasedChild, xvel, yvel); if (xvel > 0) { // 水平速度+  open(); } else if (xvel == 0 && mContent.getLeft() > mRange / 2.0f) { // 手指在菜单滑出一半多时抬起  open(); } else {  close(); } }}; /** * 修订主页面的滑动距离 */ private int fixContentSlidRange(int left) { if (left > mRange) {  return mRange; } else if (left < 0) {  return 0; } return left; }/** 伴随动画 */private void animShow(int moveContentLeft) { float percent = moveContentLeft * 1.0f / mRange;// 0~1 /** * 分析： * 菜单区域：位移动画，缩放动画，渐变动画 * 内容区域：缩放动画 * 背景区域：亮度变化 */ ViewHelper.setTranslationX(mMenu, evaluate(percent, -mRange / 1.2f, 0));// 位移动画 ViewHelper.setScaleX(mMenu, evaluate(percent, 0.6f, 1.0f));// 缩放动画 ViewHelper.setScaleY(mMenu, evaluate(percent, 0.6f, 1.0f)); ViewHelper.setAlpha(mMenu, evaluate(percent, 0.1f, 1.0f));// 渐变动画 ViewHelper.setPivotX(mContent, 0);// 缩放中心 ViewHelper.setPivotY(mContent, mHeight / 2); ViewHelper.setScaleX(mContent, evaluate(percent, 1.0f, 0.9f));// 缩放动画 ViewHelper.setScaleY(mContent, evaluate(percent, 1.0f, 0.9f)); getBackground().setColorFilter((Integer)(colorEvaluate(percent, Color.BLACK, Color.TRANSPARENT)), PorterDuff.Mode.SRC_OVER);// 亮度变化}/** 估值器，根据开始数字和结束数字，随着百分比的变化得到一个数值，详情见FloatEvaluator */ private Float evaluate(float fraction, Number startValue, Number endValue) { float startFloat = startValue.floatValue(); return startFloat + fraction * (endValue.floatValue() - startFloat); } /** 颜色取值，根据初始颜色和结束颜色，随着百分的变化取出不同的颜色，详情见ArgbEvaluator */ private Object colorEvaluate(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)))); }

 /** 菜单切换 */ public void toggle() { if(isOpen) {  close(); } else {  open(); } } /** * 打开菜单 */ private void open() { if (mViewDragHelper.smoothSlideViewTo(mContent, mRange, 0)) {// 判断主页面是否滑动到指定位置  ViewCompat.postInvalidateOnAnimation(this);// 会触发computeScroll } isOpen = true; } /** * 关闭菜单 */ private void close() { if (mViewDragHelper.smoothSlideViewTo(mContent, 0, 0)) {// 判断主页面是否滑动到指定位置  ViewCompat.postInvalidateOnAnimation(this);// 会触发computeScroll } isOpen = false; } @Override public void computeScroll() { super.computeScroll(); if (mViewDragHelper.continueSettling(true)) {// 持续执行动画，如果返回则表示动画还没有执行完  ViewCompat.postInvalidateOnAnimation(this); } }

public class MainActivity extends Activity { private SlidingMenu mSlidingMenu; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); requestWindowFeature(Window.FEATURE_NO_TITLE); setContentView(R.layout.activity_main); initView(); } private void initView() { mSlidingMenu = (SlidingMenu) findViewById(R.id.main_slidingMenu); } public void click(View view) { mSlidingMenu.toggle(); }}