Why doesnt the code from the Android SDK tutorials work out of the box?

Question

Am I missing something here?

I follow the instructions exactly on this page (and some of the other tutorials) but they always seem to be missing some key information as they dont work out of the box

I added a bunch of packages that seemed like were missing, but now I'm stuck.

http://developer.android.com/resources/tutorials/views/hello-gridview.html

Description Resource Path Location Type Conversion to Dalvik format failed with error 1 HelloGrid Unknown Android Packaging Problem

And a whole bunch of these for each of the drawable.sample_* references

Description Resource Path Location Type R.drawable.sample_0 cannot be resolved ImageAdapter.java /HelloGrid/src/com/example/ImageAdapter line 51 Java Problem

package com.example.HelloGrid;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.GridView;
import android.widget.Toast;
import android.widget.AdapterView.OnItemClickListener;

import com.example.ImageAdapter.ImageAdapter;

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

        GridView gridview = (GridView) findViewById(R.id.gridview);
        gridview.setAdapter(new ImageAdapter(this));

        gridview.setOnItemClickListener(new OnItemClickListener() {
            public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
                Toast.makeText(HelloGrid.this, "" + position, Toast.LENGTH_SHORT).show();
            }
        });
    }
}

package com.example.ImageAdapter;
import android.R;
import android.R.drawable;
import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;

public class ImageAdapter extends BaseAdapter {
    private Context mContext;

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

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

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

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

    // create a new ImageView for each item referenced by the Adapter
    public View getView(int position, View convertView, ViewGroup parent) {
        ImageView imageView;
        if (convertView == null) {  // if it's not recycled, initialize some attributes
            imageView = new ImageView(mContext);
            imageView.setLayoutParams(new GridView.LayoutParams(85, 85));
            imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
            imageView.setPadding(8, 8, 8, 8);
        } else {
            imageView = (ImageView) convertView;
        }

        imageView.setImageResource(mThumbIds[position]);
        return imageView;
    }

    // references to our images
    private Integer[] mThumbIds = {
            R.drawable.sample_2, R.drawable.sample_3,
            R.drawable.sample_4, R.drawable.sample_5,
            R.drawable.sample_6, R.drawable.sample_7,
            R.drawable.sample_0, R.drawable.sample_1,
            R.drawable.sample_2, R.drawable.sample_3,
            R.drawable.sample_4, R.drawable.sample_5,
            R.drawable.sample_6, R.drawable.sample_7,
            R.drawable.sample_0, R.drawable.sample_1,
            R.drawable.sample_2, R.drawable.sample_3,
            R.drawable.sample_4, R.drawable.sample_5,
            R.drawable.sample_6, R.drawable.sample_7
    };
}

As you can see I have all the images loaded in the /drawable directory

Answer 1

It looks like the tutorials are missing some of the package information, but if you're using eclipse it should handle most of that for you.

Answer 2

Description Resource Path Location Type R.drawable.sample_0 cannot be resolved ImageAdapter.java /HelloGrid/src/com/example/ImageAdapter line 51 Java Problem

You are missing your drawable resources. That was covered in step #2 in the instructions supplied in the tutorial.