Android listview viewpager
滑动 跳动 冲突解决

ListView中嵌套ViewPage有或者滑动手势冲突解决

在listview 上使用 addHeaderView 在第一栏添加 viewpager
当做header

如:

当触发 滑动事件 的时候容易引起 滑动冲突    (比如斜着滑动viewpager  的时候 listview会跳动)

特别是在  下拉刷新或者上拉加载 的时候 , 组件可能会传递到viewpager当中

查阅了很多的帖子  发现修改起来都非常麻烦

(1)解决方案

1. 针对viewpager 做了些修改

替换掉support.v4当中的viewpager即可:

package com.example.bz_viewpager;

import android.content.Context;
import android.support.v4.view.ViewPager;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.ViewGroup;

/**
 * viewpage 和listview 相互冲突 将父view 传递到viewpage 里面
 *
 * 使用父类的方法 parent.requestDisallowInterceptTouchEvent(true);
 *
 * 当 requestDisallowInterceptTouchEvent 如果为true的时候 表示:父view 不拦截子view的touch 事件
 *
 * 这个方法只是改变flag
 *
 * @author baozi
 *
 */
public class DecoratorViewPager extends ViewPager {
	private ViewGroup parent;

	public DecoratorViewPager(Context context) {
		super(context);
		// TODO Auto-generated constructor stub
	}

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

	public void setNestedpParent(ViewGroup parent) {
		this.parent = parent;
	}

	@Override
	public boolean dispatchTouchEvent(MotionEvent ev) {
		if (parent != null) {
			parent.requestDisallowInterceptTouchEvent(true);
		}
		return super.dispatchTouchEvent(ev);
	}

	@Override
	public boolean onInterceptTouchEvent(MotionEvent arg0) {
		if (parent != null) {
			parent.requestDisallowInterceptTouchEvent(true);
		}
		return super.onInterceptTouchEvent(arg0);
	}

	@Override
	public boolean onTouchEvent(MotionEvent arg0) {
		if (parent != null) {
			parent.requestDisallowInterceptTouchEvent(true);
		}
		return super.onTouchEvent(arg0);
	}

}

2 . 在xml里面:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="#f1f1f1" >

    <com.example.bz_viewpager.DecoratorViewPager
        android:id="@+id/vp"
        android:layout_width="match_parent"
        android:layout_height="200dp"
        android:fadingEdge="none" />

</RelativeLayout>

3. 在代码里使用

将 viewpager 的父view传递到viewpager里面

调用:       vp.setNestedpParent((ViewGroup)vp.getParent()); 方法

如下:

		lv = (ListView) findViewById(R.id.lv);

		View header = LayoutInflater.from(MainActivity.this).inflate(R.layout.viewpage_layout, null);
		DecoratorViewPager vp = (DecoratorViewPager) header.findViewById(R.id.vp);
		vp.setNestedpParent((ViewGroup)vp.getParent());

		MyPagapter myPagapter = new MyPagapter(MainActivity.this);
		vp.setAdapter(myPagapter);
		lv.addHeaderView(header);

(2)解析:

viewgroup 当中有 一个 requestDisallowInterceptTouchEvent方法

这个方法只改变flag  当 view.requestDisallowInterceptTouchEvent 参数为true的时候

view 不会拦截其子控件的 触摸事件

    /**
     * Called when a child does not want this parent and its ancestors to
     * intercept touch events with
     * {@link ViewGroup#onInterceptTouchEvent(MotionEvent)}.
     *
     * <p>This parent should pass this call onto its parents. This parent must obey
     * this request for the duration of the touch (that is, only clear the flag
     * after this parent has received an up or a cancel.</p>
     *
     * @param disallowIntercept True if the child does not want the parent to
     *            intercept touch events.
     */
    public void requestDisallowInterceptTouchEvent(boolean disallowIntercept);

贴上源码:

    public void requestDisallowInterceptTouchEvent(boolean disallowIntercept) {

        if (disallowIntercept == ((mGroupFlags & FLAG_DISALLOW_INTERCEPT) != 0)) {
            // We're already in this state, assume our ancestors are too
            return;
        }

        if (disallowIntercept) {
            mGroupFlags |= FLAG_DISALLOW_INTERCEPT;
        } else {
            mGroupFlags &= ~FLAG_DISALLOW_INTERCEPT;
        }

        // Pass it up to our parent
        if (mParent != null) {
            mParent.requestDisallowInterceptTouchEvent(disallowIntercept);
        }
    }

祝福大家每日精进

谢谢