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 Android教程網 >> Android技術 >> 關於Android編程 >> android滑動沖突的解決方案

android滑動沖突的解決方案

編輯：關於Android編程

一、前言

Android 中解決滑動的方案有2種：外部攔截法 和內部攔截法。
滑動沖突也存在2種場景: 橫豎滑動沖突、同向滑動沖突。
所以我就寫了4個例子來學習如何解決滑動沖突的，這四個例子分別為: 外部攔截法解決橫豎沖突、外部攔截法解決同向沖突、內部攔截法解決橫豎沖突、內部攔截法解決同向沖突。
先上效果圖：
這裡寫圖片描述

二、實戰
1、外部攔截法，解決橫豎沖突
思路是，重寫父控件的onInterceptTouchEvent方法，然後根據具體的需求，來決定父控件是否攔截事件。如果攔截返回返回true，不攔截返回false。關於為什麼返回true就代表攔截事件 。 如果父控件攔截了事件，則在父控件的onTouchEvent進行相應的事件處理。
我的這個例子，是一個橫向滑動的ViewGroup裡面包含了3個豎向滑動的ListView。下面我附上代碼：
HorizontalEx.java

/**
 * Created by blueberry on 2016/6/20.
 *
 * 解決交錯的滑動沖突
 *
 * 外部攔截法
 */
public class HorizontalEx extends ViewGroup {

    private static final String TAG = "HorizontalEx";

    private boolean isFirstTouch = true;
    private int childIndex;
    private int childCount;
    private int lastXIntercept, lastYIntercept, lastX, lastY;

    private Scroller mScroller;
    private VelocityTracker mVelocityTracker;

    public HorizontalEx(Context context) {
        super(context);
        init();
    }

    public HorizontalEx(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public HorizontalEx(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    private void init() {
        mScroller = new Scroller(getContext());
        mVelocityTracker = VelocityTracker.obtain();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int width = MeasureSpec.getSize(widthMeasureSpec);
        int height = MeasureSpec.getSize(heightMeasureSpec);
        int widthMode = MeasureSpec.getMode(widthMeasureSpec);
        int heightMode = MeasureSpec.getMode(heightMeasureSpec);

        childCount = getChildCount();
        measureChildren(widthMeasureSpec, heightMeasureSpec);

        if (childCount == 0) {
            setMeasuredDimension(0, 0);
        } else if (widthMode == MeasureSpec.AT_MOST && heightMode == MeasureSpec.AT_MOST) {
            width = childCount * getChildAt(0).getMeasuredWidth();
            height = getChildAt(0).getMeasuredHeight();
            setMeasuredDimension(width, height);
        } else if (widthMode == MeasureSpec.AT_MOST) {
            width = childCount * getChildAt(0).getMeasuredWidth();
            setMeasuredDimension(width, height);
        } else {
            height = getChildAt(0).getMeasuredHeight();
            setMeasuredDimension(width, height);
        }
    }

    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        int left = 0;
        for (int i = 0; i < getChildCount(); i++) {
            final View child = getChildAt(i);
            child.layout(left + l, t, r + left, b);
            left += child.getMeasuredWidth();
        }
    }

    /**
     * 攔截事件
     * @param ev
     * @return
     */
    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        boolean intercepted = false;
        int x = (int) ev.getX();
        int y = (int) ev.getY();

        switch (ev.getAction()) {
            /*如果攔截了Down事件,則子類不會拿到這個事件序列*/
            case MotionEvent.ACTION_DOWN:
                lastXIntercept = x;
                lastYIntercept = y;
                intercepted = false;
                if (!mScroller.isFinished()) {
                    mScroller.abortAnimation();
                    intercepted = true;
                }
                break;
            case MotionEvent.ACTION_MOVE:
                final int deltaX = x - lastXIntercept;
                final int deltaY = y - lastYIntercept;
                /*根據條件判斷是否攔截該事件*/
                if (Math.abs(deltaX) > Math.abs(deltaY)) {
                    intercepted = true;
                } else {
                    intercepted = false;
                }
                break;
            case MotionEvent.ACTION_UP:
                intercepted = false;
                break;

        }
        lastXIntercept = x;
        lastYIntercept = y;
        return intercepted;
    }


    @Override
    public boolean onTouchEvent(MotionEvent event) {
        int x = (int) event.getX();
        int y = (int) event.getY();
        mVelocityTracker.addMovement(event);
        ViewConfiguration configuration = ViewConfiguration.get(getContext());
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                if (!mScroller.isFinished()) {
                    mScroller.abortAnimation();
                }
                break;
            case MotionEvent.ACTION_MOVE:
                /*因為這裡父控件拿不到Down事件，所以使用一個布爾值，
                    當事件第一次來到父控件時，對lastX,lastY賦值*/
                if (isFirstTouch) {
                    lastX = x;
                    lastY = y;
                    isFirstTouch = false;
                }
                final int deltaX = x - lastX;
                scrollBy(-deltaX, 0);
                break;
            case MotionEvent.ACTION_UP:
                int scrollX = getScrollX();
                final int childWidth = getChildAt(0).getWidth();
                mVelocityTracker.computeCurrentVelocity(1000, configuration.getScaledMaximumFlingVelocity());
                float xVelocity = mVelocityTracker.getXVelocity();
                if (Math.abs(xVelocity) > configuration.getScaledMinimumFlingVelocity()) {
                    childIndex = xVelocity < 0 ? childIndex + 1 : childIndex - 1;
                } else {
                    childIndex = (scrollX + childWidth / 2) / childWidth;
                }
                childIndex = Math.min(getChildCount() - 1, Math.max(childIndex, 0));
                smoothScrollBy(childIndex * childWidth - scrollX, 0);
                mVelocityTracker.clear();
                isFirstTouch = true;
                break;
        }

        lastX = x;
        lastY = y;
        return true;
    }

    void smoothScrollBy(int dx, int dy) {
        mScroller.startScroll(getScrollX(), getScrollY(), dx, dy, 500);
        invalidate();
    }

    @Override
    public void computeScroll() {
        if (mScroller.computeScrollOffset()) {
            scrollTo(mScroller.getCurrX(), mScroller.getCurrY());
            invalidate();
        }
    }

    @Override
    protected void onDetachedFromWindow() {
        super.onDetachedFromWindow();
        mVelocityTracker.recycle();
    }
}

調用代碼：

 @Override
    public void showOutHVData(List data1, List data2, List data3) {
        ListView listView1 = new ListView(getContext());
        ArrayAdapter adapter1 = new ArrayAdapter(getContext(), android.R.layout.simple_list_item_1, data1);
        listView1.setAdapter(adapter1);

        ListView listView2 = new ListView(getContext());
        ArrayAdapter adapter2 = new ArrayAdapter(getContext(), android.R.layout.simple_list_item_1, data2);
        listView2.setAdapter(adapter2);

        ListView listView3 = new ListView(getContext());
        ArrayAdapter adapter3 = new ArrayAdapter(getContext(), android.R.layout.simple_list_item_1, data3);
        listView3.setAdapter(adapter3);

        ViewGroup.LayoutParams params
                = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,
                ViewGroup.LayoutParams.MATCH_PARENT);

        mHorizontalEx.addView(listView1, params);
        mHorizontalEx.addView(listView2, params);
        mHorizontalEx.addView(listView3, params);
    }

其實外部攔截的主要思想都在於對onInterceptTouchEvent的重寫。

@Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        boolean intercepted = false;
        int x = (int) ev.getX();
        int y = (int) ev.getY();

        switch (ev.getAction()) {
            /*如果攔截了Down事件,則子類不會拿到這個事件序列*/
            case MotionEvent.ACTION_DOWN:
                lastXIntercept = x;
                lastYIntercept = y;
                intercepted = false;
                if (!mScroller.isFinished()) {
                    mScroller.abortAnimation();
                    intercepted = true;
                }
                break;
            case MotionEvent.ACTION_MOVE:
                final int deltaX = x - lastXIntercept;
                final int deltaY = y - lastYIntercept;
                /*根據條件判斷是否攔截該事件*/
                if (Math.abs(deltaX) > Math.abs(deltaY)) {
                    intercepted = true;
                } else {
                    intercepted = false;
                }
                break;
            case MotionEvent.ACTION_UP:
                intercepted = false;
                break;

        }
        lastXIntercept = x;
        lastYIntercept = y;
        return intercepted;
    }

這幾乎是一個實現外部攔截事件的模板，這裡一定不要在ACTION_DOWN 中返回 true,否則會讓子VIew沒有機會得到事件，因為如果在ACTION_DOWN的時候返回了 true,同一個事件序列ViewGroup的disPatchTouchEvent就不會在調用onInterceptTouchEvent方法了，如果不明白可以參考我的上一遍文章。
還有就是 在ACTION_UP中返回false，因為如果父控件攔截了ACTION_UP，那麼子View將得不到UP事件，那麼將會影響子View的 Onclick方法等。但這對父控件是沒有影響的，因為如果是父控件子ACITON_MOVE中 就攔截了事件，他們UP事件必定也會交給它處理，因為有那麼一條定律叫做：父控件一但攔截了事件，那麼同一個事件序列的所有事件都將交給他處理。這條結論在我的上一篇文章中已經分析過。
最後就是在 ACTION_MOVE中根據需求決定是否攔截。

2、內部攔截法，解決橫豎沖突
內部攔截主要依賴於父控件的 requestDisallowInterceptTouchEvent方法，關於這個方法我的上篇文章其實已經分析過。他設置父控件的一個標志（FLAG_DISALLOW_INTERCEPT）
這個標志可以決定父控件是否攔截事件，如果設置了這個標志則不攔截，如果沒設這個標志，它就會調用父控件的onInterceptTouchEvent（）來詢問父控件是否攔截。但這個標志對Down事件無效。
可以參考一下源碼：
ViewGroup#dispatchTouchEvent

   // Handle an initial down.
            if (actionMasked == MotionEvent.ACTION_DOWN) {
                // Throw away all previous state when starting a new touch gesture.
                // The framework may have dropped the up or cancel event for the previous gesture
                // due to an app switch, ANR, or some other state change.
                cancelAndClearTouchTargets(ev);
                //清楚標志
                resetTouchState();
            }

            // Check for interception.
            final boolean intercepted;
            if (actionMasked == MotionEvent.ACTION_DOWN
                    || mFirstTouchTarget != null) {
                    //標志
                final boolean disallowIntercept = (mGroupFlags & FLAG_DISALLOW_INTERCEPT) != 0;
                if (!disallowIntercept) {
                    intercepted = onInterceptTouchEvent(ev);
                    ev.setAction(action); // restore action in case it was changed
                } else {
                    intercepted = false;
                }
            } else {
                // There are no touch targets and this action is not an initial down
                // so this view group continues to intercept touches.
                intercepted = true;
            }

那麼我們如果想使用 內部攔截法攔截事件。
第一步：
a、我們要重寫父控件的onInterceptTouchEvent，在ACTION_DOWN的時候返回false,負責的話子View調用requestDisallowInterceptTouchEvent也將無能為力。
b、還有就是其他事件的話都返回true,這樣就把能否攔截事件的權利交給了子View。

第二步:
在子View的dispatchTouchEvent中 來決定是否讓父控件攔截事件。
a. 先要在MotionEvent.ACTION_DOWN:的時候使用mHorizontalEx2.requestDisallowInterceptTouchEvent(true);，負責的話，下一個事件到來時，就交給父控件了。
b. 然後在MotionEvent.ACTION_MOVE: 根據業務邏輯決定是否調用mHorizontalEx2.requestDisallowInterceptTouchEvent(false);來決定父控件是否攔截事件。
上代碼：
HorizontalEx2.java
 

/**
 * Created by blueberry on 2016/6/20.
 * <p/>
 * 內部攔截
 * 和 ListViewEx配合使用
 */
public class HorizontalEx2 extends ViewGroup {

    private int lastX, lastY;
    private int childIndex;
    private Scroller mScroller;
    private VelocityTracker mVelocityTracker;

    public HorizontalEx2(Context context) {
        super(context);
        init();
    }

    public HorizontalEx2(Context context, AttributeSet attrs) {
        super(context, attrs);
        init();
    }

    public HorizontalEx2(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init();
    }

    private void init() {
        mScroller = new Scroller(getContext());
        mVelocityTracker = VelocityTracker.obtain();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int width = MeasureSpec.getSize(widthMeasureSpec);
        int widthMode = MeasureSpec.getMode(widthMeasureSpec);
        int height = MeasureSpec.getSize(heightMeasureSpec);
        int heightMode = MeasureSpec.getMode(heightMeasureSpec);

        int childCount = getChildCount();
        measureChildren(widthMeasureSpec, heightMeasureSpec);

        if (childCount == 0) {
            setMeasuredDimension(0, 0);
        } else if (widthMode == MeasureSpec.AT_MOST && heightMode == MeasureSpec.AT_MOST) {
            height = getChildAt(0).getMeasuredHeight();
            width = childCount * getChildAt(0).getMeasuredWidth();
            setMeasuredDimension(width, height);
        } else if (widthMode == MeasureSpec.AT_MOST) {
            width = childCount * getChildAt(0).getMeasuredWidth();
            setMeasuredDimension(width, height);
        } else {
            height = getChildAt(0).getMeasuredHeight();
            setMeasuredDimension(width, height);
        }
    }

    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        int leftOffset = 0;
        for (int i = 0; i < getChildCount(); i++) {
            View child = getChildAt(i);
            child.layout(l + leftOffset, t, r + leftOffset, b);
            leftOffset += child.getMeasuredWidth();
        }
    }

    /**
     * 不攔截Down事件，其他一律攔截
     * @param ev
     * @return
     */
    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        if (ev.getAction() == MotionEvent.ACTION_DOWN) {
            if (!mScroller.isFinished()) {
                mScroller.abortAnimation();
                return true;
            }
            return false;
        } else {
            return true;
        }
    }

    private boolean isFirstTouch = true;

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        int x = (int) event.getX();
        int y = (int) event.getY();
        mVelocityTracker.addMovement(event);
        ViewConfiguration configuration = ViewConfiguration.get(getContext());
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                if (!mScroller.isFinished()) {
                    mScroller.abortAnimation();
                }
                break;
            case MotionEvent.ACTION_MOVE:
                if (isFirstTouch) {
                    isFirstTouch = false;
                    lastY = y;
                    lastX = x;
                }
                final int deltaX = x - lastX;
                scrollBy(-deltaX, 0);
                break;
            case MotionEvent.ACTION_UP:
                isFirstTouch = true;
                int scrollX = getScrollX();
                mVelocityTracker.computeCurrentVelocity(1000, configuration.getScaledMaximumFlingVelocity());
                float mVelocityX = mVelocityTracker.getXVelocity();
                if (Math.abs(mVelocityX) > configuration.getScaledMinimumFlingVelocity()) {
                    childIndex = mVelocityX < 0 ? childIndex + 1 : childIndex - 1;
                } else {
                    childIndex = (scrollX + getChildAt(0).getWidth() / 2) / getChildAt(0).getWidth();
                }
                childIndex = Math.min(getChildCount() - 1, Math.max(0, childIndex));
                smoothScrollBy(childIndex*getChildAt(0).getWidth()-scrollX,0);
                mVelocityTracker.clear();
                break;
        }

        lastX = x;
        lastY = y;
        return true;
    }

    private void smoothScrollBy(int dx, int dy) {
        mScroller.startScroll(getScrollX(), getScrollY(), dx, dy,500);
        invalidate();
    }

    @Override
    public void computeScroll() {
        if(mScroller.computeScrollOffset()){
            scrollTo(mScroller.getCurrX(),mScroller.getCurrY());
            postInvalidate();
        }
    }

    @Override
    protected void onDetachedFromWindow() {
        super.onDetachedFromWindow();
        mVelocityTracker.recycle();
    }
}

ListViewEx.java


/**
 * Created by blueberry on 2016/6/20.
 * 內部攔截事件
 */
public class ListViewEx extends ListView {

    private int lastXIntercepted, lastYIntercepted;

    private HorizontalEx2 mHorizontalEx2;

    public ListViewEx(Context context) {
        super(context);
    }

    public ListViewEx(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public ListViewEx(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    public HorizontalEx2 getmHorizontalEx2() {
        return mHorizontalEx2;
    }

    public void setmHorizontalEx2(HorizontalEx2 mHorizontalEx2) {
        this.mHorizontalEx2 = mHorizontalEx2;
    }

    /**
     * 使用 outter.requestDisallowInterceptTouchEvent();
     * 來決定父控件是否對事件進行攔截
     * @param ev
     * @return
     */
    @Override
    public boolean dispatchTouchEvent(MotionEvent ev) {
        int x = (int) ev.getX();
        int y = (int) ev.getY();
        switch (ev.getAction()) {
            case MotionEvent.ACTION_DOWN:
                mHorizontalEx2.requestDisallowInterceptTouchEvent(true);
                break;
            case MotionEvent.ACTION_MOVE:
                final int deltaX = x-lastYIntercepted;
                final int deltaY = y-lastYIntercepted;
                if(Math.abs(deltaX)>Math.abs(deltaY)){
                    mHorizontalEx2.requestDisallowInterceptTouchEvent(false);
                }
                break;
            case MotionEvent.ACTION_UP:
                break;
        }
        lastXIntercepted = x;
        lastYIntercepted = y;
        return super.dispatchTouchEvent(ev);
    }
}

調用代碼：

 @Override
    public void showInnerHVData(List data1, List data2, List data3) {

        ListViewEx listView1 = new ListViewEx(getContext());
        ArrayAdapter adapter1 = new ArrayAdapter(getContext(), android.R.layout.simple_list_item_1, data1);
        listView1.setAdapter(adapter1);
        listView1.setmHorizontalEx2(mHorizontalEx2);

        ListViewEx listView2 = new ListViewEx(getContext());
        ArrayAdapter adapter2 = new ArrayAdapter(getContext(), android.R.layout.simple_list_item_1, data2);
        listView2.setAdapter(adapter2);
        listView2.setmHorizontalEx2(mHorizontalEx2);

        ListViewEx listView3 = new ListViewEx(getContext());
        ArrayAdapter adapter3 = new ArrayAdapter(getContext(), android.R.layout.simple_list_item_1, data3);
        listView3.setAdapter(adapter3);
        listView3.setmHorizontalEx2(mHorizontalEx2);

        ViewGroup.LayoutParams params
                = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,
                ViewGroup.LayoutParams.MATCH_PARENT);

        mHorizontalEx2.addView(listView1, params);
        mHorizontalEx2.addView(listView2, params);
        mHorizontalEx2.addView(listView3, params);
    }

至此，2種攔截方法已經學習完畢，下面我們來學習如何解決同向滑動沖突。
其實和上面的2個例子思路是一樣的，只是用來判斷是否攔截的那塊邏輯不同而已。

下面的例子，是一個下拉刷新的一個控件。

3、外部攔截 解決同向滑動沖突
RefreshLayoutBase.java

package com.blueberry.sample.widget.refresh;

import android.content.Context;
import android.graphics.Color;
import android.util.AttributeSet;
import android.util.DisplayMetrics;
import android.util.Log;
import android.util.TypedValue;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewGroup;
import android.view.WindowManager;
import android.widget.ProgressBar;
import android.widget.Scroller;
import android.widget.TextView;

import com.blueberry.sample.R;

/**
 * Created by blueberry on 2016/6/21.
 *
 *外部攔截(同向)
 *
 */
public abstract class RefreshLayoutBase extends ViewGroup {

    private static final String TAG = "RefreshLayoutBase";

    public static final int STATUS_LOADING = 1;
    public static final int STATUS_RELEASE_TO_REFRESH = 2;
    public static final int STATUS_PULL_TO_REFRESH = 3;
    public static final int STATUS_IDLE = 4;
    public static final int STATUS_LOAD_MORE =5;
    private static int SCROLL_DURATION =500;

    protected ViewGroup mHeadView;
    protected ViewGroup mFootView;
    private T contentView;
    private ProgressBar headProgressBar;
    private TextView headTv;
    private ProgressBar footProgressBar;
    private TextView footTv;

    private boolean isFistTouch = true;

    protected int currentStatus = STATUS_IDLE;
    private int mScreenWidth;
    private int mScreenHeight;
    private int mLastXIntercepted;
    private int mLastYIntercepted;
    private int mLastX;
    private int mLastY;
    protected int mInitScrollY = 0;
    private int mTouchSlop;

    protected Scroller mScoller;

    private OnRefreshListener mOnRefreshListener;

    public RefreshLayoutBase(Context context) {
        this(context, null);
    }

    public RefreshLayoutBase(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public RefreshLayoutBase(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        getScreenSize();
        initView();
        mScoller = new Scroller(context);
        mTouchSlop = ViewConfiguration.get(context).getScaledTouchSlop();
        setPadding(0, 0, 0, 0);
    }

    public void setContentView(T view) {
        addView(view, 1);
    }

    public OnRefreshListener getOnRefreshListener() {
        return mOnRefreshListener;
    }

    public void setOnRefreshListener(OnRefreshListener mOnRefreshListener) {
        this.mOnRefreshListener = mOnRefreshListener;
    }

    private void initView() {
        setupHeadView();
        setupFootView();
    }

    private void getScreenSize() {
        WindowManager wm = (WindowManager) getContext().getSystemService(Context.WINDOW_SERVICE);
        DisplayMetrics metrics = new DisplayMetrics();
        wm.getDefaultDisplay().getMetrics(metrics);
        mScreenWidth = metrics.widthPixels;
        mScreenHeight = metrics.heightPixels;
    }

    private int dp2px(int dp) {
        WindowManager wm = (WindowManager) getContext().getSystemService(Context.WINDOW_SERVICE);
        DisplayMetrics metrics = new DisplayMetrics();
        wm.getDefaultDisplay().getMetrics(metrics);
        return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, metrics);
    }

    /**
     * 設置頭布局
     */
    private void setupHeadView() {
        mHeadView = (ViewGroup) View.inflate(getContext(), R.layout.fresh_head_view, null);
        mHeadView.setBackgroundColor(Color.RED);
        headProgressBar = (ProgressBar) mHeadView.findViewById(R.id.head_progressbar);
        headTv = (TextView) mHeadView.findViewById(R.id.head_tv);
        /*設置 實際高度為 1/4 ，但內容區域只有 100dp*/
        ViewGroup.LayoutParams layoutParams = new ViewGroup.LayoutParams(LayoutParams.MATCH_PARENT, mScreenHeight / 4);
        mHeadView.setLayoutParams(layoutParams);
        mHeadView.setPadding(0, mScreenHeight / 4 - dp2px(100), 0, 0);
        addView(mHeadView);
    }

    /**
     * 設置尾布局
     */
    private void setupFootView() {
        mFootView = (ViewGroup) View.inflate(getContext(), R.layout.fresh_foot_view, null);
        mFootView.setBackgroundColor(Color.BLUE);
        footProgressBar = (ProgressBar) mFootView.findViewById(R.id.fresh_foot_progressbar);
        footTv = (TextView) mFootView.findViewById(R.id.fresh_foot_tv);
        addView(mFootView);
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int widthSize = MeasureSpec.getSize(widthMeasureSpec);
        int widthMode = MeasureSpec.getMode(widthMeasureSpec);
        int height = MeasureSpec.getSize(heightMeasureSpec);
        int heightMode = MeasureSpec.getMode(heightMeasureSpec);

        int finalHeight = 0;
        for (int i = 0; i < getChildCount(); i++) {
            View child = getChildAt(i);
            measureChild(child, widthMeasureSpec, heightMeasureSpec);
            finalHeight += child.getMeasuredHeight();
        }

        if (widthMode == MeasureSpec.AT_MOST && heightMode == MeasureSpec.AT_MOST) {
            widthSize = getChildAt(0).getMeasuredWidth();
            setMeasuredDimension(widthSize, finalHeight);
        } else if (widthMode == MeasureSpec.AT_MOST) {
            widthSize = getChildAt(0).getMeasuredWidth();
            setMeasuredDimension(widthSize, height);
        } else {
            setMeasuredDimension(widthSize, finalHeight);
        }

    }


    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        int topOffset = 0;
        for (int i = 0; i < getChildCount(); i++) {
            View child = getChildAt(i);
            child.layout(getPaddingLeft(), getPaddingTop() + topOffset, r, getPaddingTop() + child.getMeasuredHeight() + topOffset);
            topOffset += child.getMeasuredHeight();
        }
        mInitScrollY = mHeadView.getMeasuredHeight() + getPaddingTop();
        scrollTo(0, mInitScrollY);

    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        boolean intercepted = false;
        int x = (int) ev.getX();
        int y = (int) ev.getY();
        switch (ev.getAction()) {
            case MotionEvent.ACTION_DOWN:
                mLastXIntercepted = x;
                mLastYIntercepted = y;
                break;
            case MotionEvent.ACTION_MOVE:
                final int deltaY = x - mLastYIntercepted;
                if (isTop() && deltaY > 0 && Math.abs(deltaY) > mTouchSlop) {
                    /*下拉*/
                    intercepted = true;
                }
                break;
            case MotionEvent.ACTION_UP:
                break;
        }
        mLastXIntercepted = x;
        mLastYIntercepted = y;
        return intercepted;
    }

    private void doRefresh() {
        Log.i(TAG, "doRefresh: ");
        if (currentStatus == STATUS_RELEASE_TO_REFRESH) {
            mScoller.startScroll(0, getScrollY(), 0, mInitScrollY - getScrollY(), SCROLL_DURATION);
            currentStatus = STATUS_IDLE;
        } else if (currentStatus == STATUS_PULL_TO_REFRESH) {
            mScoller.startScroll(0,getScrollY(),0,0-getScrollY(),SCROLL_DURATION);
            if (null != mOnRefreshListener) {
                currentStatus = STATUS_LOADING;
                mOnRefreshListener.refresh();
            }
        }
        invalidate();
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        int x = (int) event.getX();
        int y = (int) event.getY();
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                if (!mScoller.isFinished()) {
                    mScoller.abortAnimation();
                }
                mLastX = x;
                mLastY = y;
                break;
            case MotionEvent.ACTION_MOVE:
                if (isFistTouch) {
                    isFistTouch = false;
                    mLastX = x;
                    mLastY = y;
                }
                final int deltaY = y - mLastY;
                if (currentStatus != STATUS_LOADING) {
                    changeScrollY(deltaY);
                }
                break;
            case MotionEvent.ACTION_UP:
                isFistTouch = true;
                doRefresh();
                break;
        }

        mLastX = x;
        mLastY = y;
        return true;
    }

    private void changeScrollY(int deltaY) {
        Log.i(TAG, "changeScrollY: ");
        int curY = getScrollY();
        if (deltaY > 0) {
            /*下拉*/
            if (curY - deltaY > getPaddingTop()) {
                scrollBy(0, -deltaY);
            }
        } else {
            /*上拉*/
            if (curY - deltaY <= mInitScrollY) {
                scrollBy(0, -deltaY);
            }
        }

        curY = getScrollY();
        int slop = mInitScrollY / 2;
        if (curY > 0 && curY <=slop) {
            currentStatus = STATUS_PULL_TO_REFRESH;
        } else if (curY > 0 && curY >= slop) {
            currentStatus = STATUS_RELEASE_TO_REFRESH;
        }
    }

    @Override
    public void computeScroll() {
        if (mScoller.computeScrollOffset()) {
            scrollTo(mScoller.getCurrX(), mScoller.getCurrY());
            postInvalidate();
        }
    }

    /**
     * 加載完成調用這個方法
     */
    public void refreshComplete() {
        mScoller.startScroll(0, getScrollY(), 0, mInitScrollY - getScrollY(), SCROLL_DURATION);
        currentStatus = STATUS_IDLE;
        invalidate();
    }

    /**
     * 顯示 Footer
     */
    public void showFooter() {
        if(currentStatus==STATUS_LOAD_MORE) return ;
        currentStatus = STATUS_LOAD_MORE ;
        mScoller.startScroll(0, getScrollY(), 0, mFootView.getMeasuredHeight()
                , SCROLL_DURATION);
        invalidate();

    }


    /**
     * loadMore完成之後調用
     */
    public void footerComplete() {
        mScoller.startScroll(0, getScrollY(), 0, mInitScrollY - getScrollY(), SCROLL_DURATION);
        invalidate();
        currentStatus = STATUS_IDLE;
    }

    public interface OnRefreshListener {
        void refresh();
    }

    abstract boolean isTop();

    abstract boolean isBottom();

}

它是一個抽象類，需要編寫子類繼承isTop()和 isBottom()方法、
下面給出它的一個實現類：

package com.blueberry.sample.widget.refresh;

import android.content.Context;
import android.util.AttributeSet;
import android.widget.AbsListView;
import android.widget.ListView;

/**
 * Created by blueberry on 2016/6/21.
 *
 * RefreshLayoutBase 的一個實現類
 */
public class RefreshListView extends RefreshLayoutBase {

    private static final String TAG = "RefreshListView";

    private ListView listView;
    private OnLoadListener loadListener;

    public RefreshListView(Context context) {
        super(context);
    }

    public RefreshListView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public RefreshListView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    public ListView getListView() {
        return listView;
    }

    public void setListView(final ListView listView) {
        this.listView = listView;
        setContentView(listView);

        this.listView.setOnScrollListener(new AbsListView.OnScrollListener() {
            @Override
            public void onScrollStateChanged(AbsListView view, int scrollState) {
            }

            @Override
            public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {

                /*這裡存在一個bug: 當listView滑動到底部的時候，如果下拉也會出現footer
                * 這是因為，暫時還沒有想到如何判斷是下拉還是上拉。
                * 如果要解決此問題，我覺得應該重寫listView 的onTouchEvent來判斷手勢方向
                * 次模塊主要解決豎向滑動沖突，故現將此問題放下。
                * */
                if (currentStatus == STATUS_IDLE
                        && getScrollY() <= mInitScrollY && isBottom()
                        ) {
                    showFooter();
                    if (null != loadListener) {
                        loadListener.onLoadMore();
                    }
                }

            }
        });
    }

    public OnLoadListener getLoadListener() {
        return loadListener;
    }

    public void setLoadListener(OnLoadListener loadListener) {
        this.loadListener = loadListener;
    }

    @Override
    boolean isTop() {
        return listView.getFirstVisiblePosition() == 0
                && getScrollY() <= mHeadView.getMeasuredHeight();
    }

    @Override
    boolean isBottom() {
        return listView.getLastVisiblePosition() == listView.getAdapter().getCount() - 1;
    }

    public interface OnLoadListener {
        void onLoadMore();
    }
}

4、內部攔截法解決同向滑動
同樣是一個下拉刷新組件，因為實現原理都一樣，所以這個寫的比較隨意些。主要還是如果解決滑動沖突。
RefreshLayoutBase2.java

package com.blueberry.sample.widget.refresh;

import android.content.Context;
import android.graphics.Color;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Scroller;

import com.blueberry.sample.R;

import java.util.ArrayList;
import java.util.List;

/**
 * Created by blueberry on 2016/6/22.
 * 結合內部類 ListVieEx
 * 內部攔截法，同向
 */
public class RefreshLayoutBase2 extends ViewGroup {

    private static final String TAG = "RefreshLayoutBase2";

    private static List datas;

    static {
        datas = new ArrayList<>();
        for (int i = 0; i < 40; i++) {
            datas.add("數據—" + i);
        }
    }

    private ViewGroup headView;
    private ListViewEx lv;

    private int lastY;
    public int mInitScrollY;

    private Scroller mScroller;

    public RefreshLayoutBase2(Context context) {
        this(context, null);
    }

    public RefreshLayoutBase2(Context context, AttributeSet attrs) {
        this(context, attrs, 0);

    }

    public RefreshLayoutBase2(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        mScroller = new Scroller(context);
        setupHeadView(context);
        setupContentView(context);

    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int widthSize = MeasureSpec.getSize(widthMeasureSpec);
        int widthMode = MeasureSpec.getMode(widthMeasureSpec);
        int height = MeasureSpec.getSize(heightMeasureSpec);
        int heightMode = MeasureSpec.getMode(heightMeasureSpec);

        int finalHeight = 0;
        for (int i = 0; i < getChildCount(); i++) {
            View child = getChildAt(i);
            measureChild(child, widthMeasureSpec, heightMeasureSpec);
            finalHeight += child.getMeasuredHeight();
        }

        if (widthMode == MeasureSpec.AT_MOST && heightMode == MeasureSpec.AT_MOST) {
            widthSize = getChildAt(0).getMeasuredWidth();
            setMeasuredDimension(widthSize, finalHeight);
        } else if (widthMode == MeasureSpec.AT_MOST) {
            widthSize = getChildAt(0).getMeasuredWidth();
            setMeasuredDimension(widthSize, height);
        } else {
            setMeasuredDimension(widthSize, finalHeight);
        }

    }

    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        int topOffset = 0;
        for (int i = 0; i < getChildCount(); i++) {
            View child = getChildAt(i);
            child.layout(getPaddingLeft(), getPaddingTop() + topOffset, r, getPaddingTop() + child.getMeasuredHeight() + topOffset);
            topOffset += child.getMeasuredHeight();
        }
        mInitScrollY = headView.getMeasuredHeight() + getPaddingTop();
        scrollTo(0, mInitScrollY);

    }

    /**
     * 不攔截Down 其他一律攔截
     * @param ev
     * @return
     */
    @Override
    public boolean onInterceptTouchEvent(MotionEvent ev) {
        if (ev.getAction() == MotionEvent.ACTION_DOWN) return false;
        return true;
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        int y = (int) event.getY();
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                break;
            case MotionEvent.ACTION_MOVE:
                final int deltaY = y-lastY;
                Log.i(TAG, "onTouchEvent: deltaY: "+deltaY);
                if (deltaY >= 0 && lv.isTop() && getScrollY() - deltaY >=getPaddingTop()) {
                        scrollBy(0, -deltaY);
                }
                break;
            case MotionEvent.ACTION_UP:
                this.postDelayed(new Runnable() {
                    @Override
                    public void run() {
                        mScroller.startScroll(0,getScrollY(),0,mInitScrollY-getScrollY());
                        invalidate();
                    }
                },2000);
                break;
        }

        lastY = y ;
        return true;
    }

    private void setupHeadView(Context context) {
        headView = (ViewGroup) View.inflate(context, R.layout.fresh_head_view, null);
        headView.setBackgroundColor(Color.RED);
        ViewGroup.LayoutParams params = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, 300);
        addView(headView, params);
    }

    public void setupContentView(Context context) {
        lv = new ListViewEx(context, this);
        lv.setBackgroundColor(Color.BLUE);
        ArrayAdapter adapter = new ArrayAdapter(getContext(), android.R.layout.simple_list_item_1, datas);
        lv.setAdapter(adapter);
        addView(lv, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
    }

    @Override
    public void computeScroll() {
        if(mScroller.computeScrollOffset()){
            scrollTo(mScroller.getCurrX(),mScroller.getCurrY());
            postInvalidate();
        }
    }

    public static class ListViewEx extends ListView {

        private RefreshLayoutBase2 outter;

        public ListViewEx(Context context, RefreshLayoutBase2 outter) {
            super(context);
            this.outter = outter;
        }

        public ListViewEx(Context context, AttributeSet attrs) {
            super(context, attrs);
        }

        public ListViewEx(Context context, AttributeSet attrs, int defStyleAttr) {
            super(context, attrs, defStyleAttr);
        }

        /**
         * 使用 outter.requestDisallowInterceptTouchEvent();
         * 來決定父控件是否對事件進行攔截
         * @param ev
         * @return
         */
        @Override
        public boolean dispatchTouchEvent(MotionEvent ev) {
            switch (ev.getAction()) {
                case MotionEvent.ACTION_DOWN:
                    outter.requestDisallowInterceptTouchEvent(true);
                    break;
                case MotionEvent.ACTION_MOVE:

                    if ( isTop() && outter.getScrollY() <= outter.mInitScrollY) {
                        outter.requestDisallowInterceptTouchEvent(false);
                    }
                    break;

            }
            return super.dispatchTouchEvent(ev);
        }

        public boolean isTop() {
            return getFirstVisiblePosition() ==0;
        }
    }
}
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