Creating a custom Gallery - overriding onFling

Question

So, I've followed this particular thread (How to stop scrolling in a Gallery Widget?) yet I am unable to get it to work properly.

I've created a custom MyGallery class extending Gallery. I've added the code in the link above...am I supposed to add <com.example.mygallery to the XML file? If so, do I also add the import to the java file or is this not needed because of the XML file? I'm so very confused.

I want to simply make the gallery move one image at a time per fling.

XML file:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="@drawable/carlot_background"
    >
<com.gallerytest.mygallery
    android:id="@+id/thisgallery"
    android:gravity="center"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content" />
</LinearLayout>

mygallery.java:

package com.gallerytest;

import android.content.Context;
import android.util.AttributeSet;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.widget.Gallery;

public class mygallery extends Gallery {

    public mygallery(Context ctx, AttributeSet attrSet) {
        super(ctx);
        // TODO Auto-generated constructor stub
    }

    private boolean isScrollingLeft(MotionEvent e1, MotionEvent e2){ 
           return e2.getX() > e1.getX(); 
        }

    @Override
    public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY){
      int kEvent;
      if(isScrollingLeft(e1, e2)){ //Check if scrolling left
        kEvent = KeyEvent.KEYCODE_DPAD_LEFT;
      }
      else{ //Otherwise scrolling right
        kEvent = KeyEvent.KEYCODE_DPAD_RIGHT;
      }
      onKeyDown(kEvent, null);
      return true;  
    }

}

main.java: package com.gallerytest;

import android.app.Activity;
import android.content.Context;
import android.content.res.TypedArray;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.Toast;
import android.widget.AdapterView.OnItemClickListener;

public class main extends Activity {
    /** Called when the activity is first created. */

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

         mygallery gallery = (mygallery) findViewById(R.id.thisgallery);

         gallery.setAdapter(new AddImgAdp(this));

         gallery.setOnItemClickListener(new OnItemClickListener() {
            public void onItemClick(AdapterView parent, View v, int position, long id) {

                Toast.makeText(main.this, "Position=" + position, Toast.LENGTH_SHORT).show();
            }

        });

    }

    public class AddImgAdp extends BaseAdapter {
        int GalItemBg;
        private Context cont;


        private Integer[] Imgid = {
                R.drawable.image1, R.drawable.image2, R.drawable.image3, R.drawable.image4, R.drawable.image5};

        public AddImgAdp(Context c) {
            cont = c;
            TypedArray typArray = obtainStyledAttributes(R.styleable.Gallery1);
            GalItemBg = typArray.getResourceId(R.styleable.Gallery1_android_galleryItemBackground, 0);
            typArray.recycle();
        }

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

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

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

        public View getView(int position, View convertView, ViewGroup parent) {
            ImageView imgView = new ImageView(cont);

            imgView.setImageResource(Imgid[position]);

            imgView.setScaleType(ImageView.ScaleType.FIT_CENTER);
            imgView.setBackgroundResource(0x0106000d);
            imgView.setLayoutParams(new mygallery.LayoutParams(300, 240));

            return imgView;
        }
    }
}

I'd love some help. Thanks!!

~Rick

Answer 1

Just add the attrSet param to the constructor of your custom gallery:

super(ctx, attrSet);

This worked for me. Leo Vannucci

Answer 2

Yes. You should just use com.gallerytest.mygallery instead of Gallery in XMLs. Everything will be working fine becuase mygallery is a subclass of Gallery. No need for imports in XML.

Answer 3

Changing the XML was key...i had been getting TypeCastException for sometime and couldn't find the reason in my code. Finally found in this post " You should just use com.gallerytest.mygallery instead of Gallery in XMLs" and solved my problem. thanks a lot.