Android新闻客户端水平导航条效果

核心代码：

package com.liuyk.widget;import android.content.Context;import android.graphics.Color;import android.util.AttributeSet;import android.view.LayoutInflater;import android.view.View;import android.widget.HorizontalScrollView;import android.widget.LinearLayout;import java.util.ArrayList;/** * 水平滚动栏 * * @author liuyk */public abstract class HorizontalNavigationBar<T> extends HorizontalScrollView {    //分割线颜色    protected int mSplitColor = Color.RED;    private int mCurrentPosition = -1;    private LinearLayout mItemViewContainer;    private OnHorizontalNavigationSelectListener mOnHorizontalNavigationSelectListener;    /**     * 是否有下划线     */    private boolean isChannelSplit;    private ArrayList<T> mItems;    public HorizontalNavigationBar(Context paramContext) {        this(paramContext, null);    }    public HorizontalNavigationBar(Context paramContext, AttributeSet paramAttributeSet) {        this(paramContext, paramAttributeSet, 0);    }    public HorizontalNavigationBar(Context paramContext, AttributeSet paramAttributeSet, int paramInt) {        super(paramContext, paramAttributeSet, paramInt);        initView();    }    private void initView() {        View view = LayoutInflater.from(getContext()).inflate(R.layout.horizontal_navigation_container, this);        mItemViewContainer = (LinearLayout) view.findViewById(R.id.horizontal_navigation_container);    }    @Override    protected void onFinishInflate() {        super.onFinishInflate();    }    public void setItems(ArrayList<T> items) {        if (items == null) return;        this.mItems = items;        this.mItemViewContainer.removeAllViews();        for (int i = 0; i < items.size(); i++) {            final HorizontalNavigationItemView itemView = new HorizontalNavigationItemView(getContext());            itemView.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.MATCH_PARENT));            itemView.setChannelSplit(isChannelSplit);            itemView.setSplitColor(mSplitColor);            renderingItemView(itemView, i, mCurrentPosition);            final int index = i;            itemView.setOnClickListener(new OnClickListener() {                public void onClick(View paramAnonymousView) {                    HorizontalNavigationBar.this.setCurrentChannelItem(index);                    if (mOnHorizontalNavigationSelectListener != null) {                        mOnHorizontalNavigationSelectListener.select(index);                    }                }            });            this.mItemViewContainer.addView(itemView);        }        scrollTo(0, 0);    }    public void setCurrentChannelItem(int index) {        int childCount = this.mItemViewContainer.getChildCount();        if (index > childCount - 1) {            throw new RuntimeException("position more size");        }        if (index == this.mCurrentPosition) {            return;        }        this.mCurrentPosition = index;        for (int i = 0; i < childCount; i++) {            HorizontalNavigationItemView itemView = (HorizontalNavigationItemView) this.mItemViewContainer.getChildAt(i);            itemView.setChecked(i == mCurrentPosition);        }        if (mCurrentPosition == 0) {            scrollTo(0, 0);        } else {            int left = this.mItemViewContainer.getChildAt(index).getLeft();            smoothScrollTo(left, 0);        }    }    public boolean isChannelSplit() {        return isChannelSplit;    }    //分割线颜色    public void setSplitColor(int resId) {        mSplitColor = resId;    }    //是否有下划线    public void setChannelSplit(boolean channelSplit) {        isChannelSplit = channelSplit;    }    public void addOnHorizontalNavigationSelectListener(OnHorizontalNavigationSelectListener onHorizontalNavigationSelectListener) {        this.mOnHorizontalNavigationSelectListener = onHorizontalNavigationSelectListener;    }    public T getItem(int position) {        return mItems == null ? null : mItems.get(position);    }    /**     * 渲染子ItemView     *     * @param itemView        子View     * @param index           子View的索引位置     * @param currentPosition 当前选中位置     */    public abstract void renderingItemView(HorizontalNavigationItemView itemView, int index, int currentPosition);    public interface OnHorizontalNavigationSelectListener {        void select(int index);    }}

源码地址：https://github.com/liuyak/HorizontalNavigationBar