android - 在 Android App 中添加滑动手势

Question

我正在尝试向我的应用添加滑动手势。我遵循了教程，但似乎无法正常工作。我做错了什么？

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.net.Uri;
import android.os.Bundle;
import android.view.GestureDetector;
import android.view.LayoutInflater;
import android.view.MotionEvent;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;

public class Home extends Activity {

        private static final int SWIPE_MIN_DISTANCE = 120;
        private static final int SWIPE_THRESHOLD_VELOCITY = 200;
        GridView gridMenu;
        private GestureDetector gestureDetector;

        /** Called when the activity is first created. */
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.home);

            gridMenu = (GridView)findViewById(R.id.gridMenu);

            gridMenu.setAdapter(new ImageAdapter(this));
            gridMenu.setHorizontalScrollBarEnabled(false);

            gestureDetector = new GestureDetector(this, new OnSwipeGestureListener());

            gridMenu.setOnItemClickListener(new OnItemClickListener(){
            public void onItemClick(AdapterView<?>parent, View v, int position, long id){

                Intent url;
                Bundle urlBundle = new Bundle(); 

                switch(position){
                case 0: 
                    // Public Affairs

                    url = new Intent(Home.this, PublicAffairs.class); 
                    urlBundle.putString("url", "http://kyfbnewsroom.com/category/public-affairs/feed");
                    url.putExtras(urlBundle);
                    startActivity(url);
                    break;

                case 1:
                    // Action Alerts  

                    url = new Intent(Home.this, ActionAlerts.class); 
                    urlBundle.putString("url", "http://kyfbnewsroom.com/category/public-affairs/notifications/feed");
                    url.putExtras(urlBundle);
                    startActivity(url);     
                    break;

                case 2:
                    // Market Updates 

                    url = new Intent(Home.this, MarketUpdates.class); 
                    urlBundle.putString("url", "http://kyfbnewsroom.com/category/market-updates/feed");
                    url.putExtras(urlBundle);
                    startActivity(url);  
                    break;

                case 3: 
                    // Ag Stories

                    url = new Intent(Home.this, AgNews.class); 
                    urlBundle.putString("url", "http://kyfbnewsroom.com/category/ag-news/feed");
                    url.putExtras(urlBundle);
                    startActivity(url);  
                    break;

                case 4:
                    // KFB News

                    url = new Intent(Home.this, KFBMagazine.class); 
                    urlBundle.putString("url", "http://kyfbnewsroom.com/category/kfb-news/feed/");
                    url.putExtras(urlBundle);
                    startActivity(url);  
                    break;

                case 5:
                   // Member Benefits


                    Intent member = new Intent(Home.this, MemberBenefits.class); 
                    startActivity(member);
                        //overridePendingTransition(R.anim.fadeon, R.anim.fadeoff); 
                    break;

                case 6:
                //Monthly Video

                startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("http://www.youtube.com/user/kentuckyfarmbureau")));
                    break;

                case 7:
                    // Photos

                 // Intent flickr = new Intent(Home.this, Flickr.class);                    

                      // startActivity(flickr);
                        //overridePendingTransition(R.anim.fadeon, R.anim.fadeoff); 

                    // Farm Markets

                    Intent markets = new Intent(Home.this, RSFM.class);
                    startActivity(markets);
                    break;

                case 8:
                    // Social Media

                  Intent social = new Intent(Home.this, SocialMedia.class);                     
                  startActivity(social);
                 //overridePendingTransition(R.anim.fadeon, R.anim.fadeoff); 
                    break;
                }   
            }
           }); 
        }

        @Override
        public boolean onTouchEvent(MotionEvent event)
        {
            if (gestureDetector.onTouchEvent(event))
            {
                return true;
            }
            else
            {
                return false;
            }
        }

        private class OnSwipeGestureListener extends GestureDetector.SimpleOnGestureListener
        {
            @Override
            public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY)
            {
                float deltaX = e2.getX() - e1.getX();
                if ((Math.abs(deltaX) < SWIPE_MIN_DISTANCE) || (Math.abs(velocityX) < SWIPE_THRESHOLD_VELOCITY))
                {
                    return false;
                }
                else
                {
                    if (deltaX < 0)
                    {
                        handleSwipeLeftToRight();
                    }
                    else
                    {
                        handleSwipeRightToLeft();
                    }
                }
                return true;
            }
        }

        private void handleSwipeLeftToRight()
        {
            System.out.println("Swipe Left to Right");
            Intent intent = new Intent(Home.this, RSFM.class);
            startActivity(intent);
        }

        private void handleSwipeRightToLeft()
        {
            System.out.println("Swipe Right to Left");
            Intent intent = new Intent(Home.this, RSFM.class);
            startActivity(intent);
        }



        /*
         * This method is used to check whether there is internet connection or not.
         */
        public boolean isConnect() {
            ConnectivityManager cm =
                (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
            NetworkInfo netInfo = cm.getActiveNetworkInfo();
            if (netInfo != null && netInfo.isConnectedOrConnecting()) {
                return true;
            }
            return false;
        }

    public class ImageAdapter extends BaseAdapter {

            Context mContext;
            public static final int ACTIVITY_CREATE = 10;

            public ImageAdapter(Context c){
                mContext = c;
            }

            public int getCount(){
                return MenuIcon.length;
            }

            public Object getItem(int position){
                return null;
            }

            public long getItemId(int position){
                return 0;
            }

            public View getView(int position, View convertView, ViewGroup parent){
                View v;
                if(convertView == null){
                    LayoutInflater li = getLayoutInflater();
                    v = li.inflate(R.layout.grid_layout, null);
                }else{
                    v = convertView;
                }

                ImageView imgIcon = (ImageView) v.findViewById(R.id.imgIcon);
                imgIcon.setImageResource(MenuIcon[position]);
                //TextView txtIcon = (TextView) v.findViewById (R.id.txtIcon);
                //txtIcon.setText(TextIcon[position]);

                return v;
            }

            private Integer[] MenuIcon = {
                    R.drawable.publicaffairs, R.drawable.actionalerts, R.drawable.marketupdates, 
                    R.drawable.agnews, R.drawable.kfbmagazine, R.drawable.memberbenefits, R.drawable.monthlyvideo, 
                    R.drawable.roadsidemarkets, R.drawable.socialmedia
            };


        }


} 

Answer 1

您想捕捉 GridView 上的触摸吗？

您的 onTouchEvent() 仅在被触摸的 View (在您的 Activity 中)未自行处理(如 ImageView)时调用。 GridView 可以(因为它是可点击的)!

尝试在您的 GridView 上设置一个 OnTouchListener 并将这些事件推送到您的 GestureDetector。