Simulate Android Event

activity_list_view.xml

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.baozs.demos.sqlbritedemo2017.listview.ListViewActivity">
    <com.baozs.demos.sqlbritedemo2017.listview.MyAutoPullDownListView
        android:id="@+id/listview"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        />
</FrameLayout>

ListViewActivity.java

package com.baozs.demos.sqlbritedemo2017.listview;

import android.content.Context;
import android.support.annotation.LayoutRes;
import android.support.annotation.NonNull;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;

import com.baozs.demos.sqlbritedemo2017.R;

public class ListViewActivity extends AppCompatActivity {

    private MyAutoPullDownListView mListView;
    private MyAdapter mAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_list_view);

        mListView = (MyAutoPullDownListView) findViewById(R.id.listview);
        mListView.setOverscrollHeader(ContextCompat.getDrawable(this, R.drawable.rockman));
        mAdapter = new MyAdapter(this, android.R.layout.simple_list_item_1);
        mListView.setAdapter(mAdapter);
        mListView.setOverScrollMode(View.OVER_SCROLL_ALWAYS);

        for (int i = 0; i < 100; i++) {
            mAdapter.add("Hello");
            mAdapter.add("World");
        }
        mListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                mListView.overScrollDown();
            }
        });
    }

    public static class MyAdapter extends ArrayAdapter<String> {
        public MyAdapter(@NonNull Context context, @LayoutRes int resource) {
            super(context, resource);
        }
    }
}

MyAutoPullDownListView.java

package com.baozs.demos.sqlbritedemo2017.listview;

import android.content.Context;
import android.support.v4.view.MotionEventCompat;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.widget.ListView;
import android.widget.OverScroller;

import static android.R.attr.duration;
import static android.R.interpolator.linear;
import static android.support.v4.widget.ViewDragHelper.INVALID_POINTER;

/**
 * Created by vashzhong on 2017/5/15.
 */

public class MyAutoPullDownListView extends ListView {

    public MyAutoPullDownListView(Context context) {
        super(context);
        init(context, null);
    }

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

    private void init(Context context, AttributeSet attrs) {
    }

    public void overScrollDown() {
        post(new Runnable() {
            @Override
            public void run() {
                final MotionEvent event = MotionEvent.obtain(System.currentTimeMillis(), System.currentTimeMillis(), MotionEvent.ACTION_DOWN, getWidth() / 2, getHeight() / 2, 0);
                dispatchTouchEvent(event);
                event.recycle();
            }
        });

        postDelayed(new Runnable() {
            @Override
            public void run() {
                final MotionEvent event = MotionEvent.obtain(System.currentTimeMillis(), System.currentTimeMillis(), MotionEvent.ACTION_MOVE, getWidth() / 2, getHeight() / 2, 0);
                dispatchTouchEvent(event);
                event.recycle();
            }
        }, 50);

        postDelayed(new Runnable() {
            @Override
            public void run() {
                final MotionEvent event = MotionEvent.obtain(System.currentTimeMillis(), System.currentTimeMillis(), MotionEvent.ACTION_MOVE, getWidth() / 2, getHeight() / 2 + 400, 0);
                dispatchTouchEvent(event);
                event.recycle();
            }
        }, 100);

        postDelayed(new Runnable() {
            @Override
            public void run() {
                final MotionEvent event = MotionEvent.obtain(System.currentTimeMillis(), System.currentTimeMillis(), MotionEvent.ACTION_UP, getWidth() / 2, getHeight() / 2 + 400, 0);
                dispatchTouchEvent(event);
                event.recycle();
            }
        }, 3000);
    }
}