滑动隐藏和显示标题栏

1.MainActivity.java

import android.content.Context;import android.support.v7.app.ActionBarActivity;import android.os.Bundle;import android.view.LayoutInflater;import android.view.MotionEvent;import android.view.View;import android.view.ViewConfiguration;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.ListView;import android.widget.RelativeLayout;import android.animation.Animator;import android.animation.ObjectAnimator;import android.widget.TextView;import java.util.ArrayList;import java.util.List;public class MainActivity extends ActionBarActivity {    private ListView mListView;    private RelativeLayout mTitle;    private int mTouchSlop;         //滑动限定停止值    private ListAdapter mAdapter;   //适配器    private float mFirstY;    private float mCurrentY;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        mTouchSlop = ViewConfiguration.get(this).getScaledTouchSlop();        initView();        showOrHide(true);    }    private void initView() {        mListView = (ListView) findViewById(R.id.listview);        mTitle = (RelativeLayout) findViewById(R.id.id_title);        mAdapter = new ListAdapter(this,getData());        mListView.setAdapter(mAdapter);        mListView.setOnTouchListener(new View.OnTouchListener() {            @Override            public boolean onTouch(View v, MotionEvent event) {                switch (event.getAction()) {                    case MotionEvent.ACTION_DOWN:                        mFirstY = event.getY();                        break;                    case MotionEvent.ACTION_MOVE:                        mCurrentY = event.getY();                        if (mCurrentY - mFirstY > mTouchSlop) {                            showOrHide(true); //下滑 显示titlebar                        } else if (mFirstY - mCurrentY > mTouchSlop) {                            showOrHide(false); //上滑 隐藏titlebar                        }                        break;                    case MotionEvent.ACTION_UP:                        break;                }                return false;            }        });    }    private List<String> getData() {        List<String> data = new ArrayList<>();        for(int i = 0;i < 30;i++){            data.add(String.valueOf(i));        }        return data;    }    private Animator mAnimationTitle;    private Animator mAnimationContent;    private void showOrHide(boolean tag) {        if (mAnimationTitle != null && mAnimationTitle.isRunning()) {            mAnimationTitle.cancel();        }        if (mAnimationContent != null && mAnimationContent.isRunning()) {            mAnimationContent.cancel();        }        if (tag) {            mAnimationTitle = ObjectAnimator.ofFloat(mTitle, "translationY", mTitle.getTranslationY(), 0);            mAnimationContent = ObjectAnimator.ofFloat(mListView, "translationY", mListView.getTranslationY(), getResources().getDimension(R.dimen.title));        } else {            mAnimationTitle = ObjectAnimator.ofFloat(mTitle,"translationY",mTitle.getTranslationY(),-mTitle.getHeight());            mAnimationContent = ObjectAnimator.ofFloat(mListView,"translationY",mListView.getTranslationY(),0);        }        mAnimationTitle.start();        mAnimationContent.start();    }    class ListAdapter extends BaseAdapter{        private List<String> list;        private LayoutInflater inflater;        public ListAdapter(Context content,List<String> list){            this.list = list;            inflater = LayoutInflater.from(content);        }        @Override        public int getCount() {            return list == null ? 0 :list.size();        }        @Override        public Object getItem(int position) {            return list.get(position);        }        @Override        public long getItemId(int position) {            return position;        }        @Override        public View getView(int position, View convertView, ViewGroup parent) {            ViewHolper vh = null;            if(convertView == null){                vh = new ViewHolper();                convertView = inflater.inflate(R.layout.lv_item,parent,false);                vh.text = (TextView) convertView.findViewById(R.id.list_item);                convertView.setTag(vh);            }else{                vh = (ViewHolper) convertView.getTag();            }            vh.text.setText(list.get(position));            return convertView;        }        class ViewHolper{            TextView text;        }    }}

2.标题栏的高度值

<dimen name="title">50dp</dimen>

3.布局文件

lv_item.xml

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent">    <TextView        android:id="@+id/list_item"        android:layout_width="match_parent"        android:layout_height="35dp"        android:gravity="center"        /></LinearLayout>

activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    tools:context=".MainActivity">    <RelativeLayout        android:id="@+id/id_title"        android:background="#0ac39e"        android:layout_width="match_parent"        android:layout_height="@dimen/title">        <TextView            android:text="两颗心"            android:layout_centerInParent="true"            android:textSize="22sp"            android:textColor="#ffffff"            android:layout_width="wrap_content"            android:layout_height="wrap_content" />    </RelativeLayout>    <ListView        android:id="@+id/listview"        android:layout_width="match_parent"        android:layout_height="match_parent"/></RelativeLayout>