Android使用原始资源文件的介绍

/* AUTO-GENERATED FILE.  DO NOT MODIFY.
 *
 * This class was automatically generated by the
 * aapt tool from the resource data it found.  It
 * should not be modified by hand.
 */
package com.android.explorer;
public final class R {
    public static final class attr {
    }
    public static final class drawable {
        public static final int icon=0x7f020000;
    }
    public static final class id {
        public static final int action=0x7f060004;
        public static final int description_panel=0x7f060001;
        public static final int fileinfo=0x7f060003;
        public static final int filename=0x7f060002;
        public static final int linearlayout_test_1=0x7f060005;
        public static final int linearlayout_test_2=0x7f060006;
        public static final int linearlayout_test_3=0x7f060007;
        public static final int thumbnail=0x7f060000;
    }
    public static final class layout {
        public static final int fileant_list_item=0x7f030000;
        public static final int linearlayout_test=0x7f030001;
    }
    public static final class raw {
        public static final int androidmanifest=0x7f040000;
    }
    public static final class string {
        public static final int app_name=0x7f050001;
        public static final int hello=0x7f050000;
    }
}

InputStream in = Context.getResources().openRawResource(R.id.filename);

InputStream in = mAssetManager.open("hello.txt"); // '/assets/hello.txt'
InputStream in2 = mAssetManager.open("config/ui.txt"); // '/assets/config/ui.txt'

public finalString[]list(String path)
Since: API Level 1
Return a String array of all the assets at the given path.
Parameters
path  A relative path within the assets, i.e., "docs/home.html".
Returns
•String[] Array of strings, one for each asset. These file names are relative to 'path'. You can open the file by concatenating 'path' and a name in the returned string (via File) and passing that to open().

mAssetManager.list(".");  // returns array size is 0
mAssetManager.list("/");  // returns [AndroidManifest.xml, META-INF, assets, classes.dex, res, resources.arsc] // don't worry, u can see these files though, no way to access them
mAssetManager.list("/assets");  // returns array size is 0
//Google了一下，找到了正解：
mAssetManager.list("");  // returns stuff in /assets

File File.createTempFile(String prefix, String suffix); 
File File.createTempFile(String prefix, String suffix, File path); 

package com.android.explorer;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import android.app.ListActivity;
import android.content.Context;
import android.content.Intent;
import android.content.res.AssetManager;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.text.TextUtils;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.MimeTypeMap;
import android.widget.BaseAdapter;
import android.widget.ImageButton;
import android.widget.LinearLayout;
import android.widget.TextView;
/*
 * Explore all stuff in /assets and perform actions specified by users.
 */
public class FileAntActivity extends ListActivity {
    private static final String TAG = "FileAntActivity";
    private AssetManager mAssetManager;
    private static final String EXTRA_CURRENT_DIRECTORY = "current_directory";
    private static final String EXTRA_PARENT = "parent_directory";
    public static final String FILEANT_VIEW = "com.android.fileant.VIEW";
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        Intent intent = getIntent();
        String current = null;
        String parent = null;
        if (intent != null && intent.hasExtra(EXTRA_CURRENT_DIRECTORY)) {
            current = intent.getStringExtra(EXTRA_CURRENT_DIRECTORY);
        }
        if (current == null) {
            current = "";
        }
        if (intent != null && intent.hasExtra(EXTRA_PARENT)) {
            parent = intent.getStringExtra(EXTRA_PARENT);
        }
        if (parent == null) {
            parent = "";
        }
        mAssetManager = getAssets();
        if (TextUtils.isEmpty(parent)) {
            setTitle("/assets");
        } else {
            setTitle(parent);
        }
        try {
            // List all the stuff in /assets
            if (!TextUtils.isEmpty(parent)) {
                current = parent + File.separator + current;
            }
            Log.e(TAG, "current: '" + current + "'");
            String[] stuff = mAssetManager.list(current);
            setListAdapter(new FileAntAdapter(this, stuff, current));
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private class FileAntAdapter extends BaseAdapter {
        private Context mContext;
        private String[] mEntries;
        private String mParentDirectory;

        public FileAntAdapter(Context context, String[] data, String parent) {
            mContext = context;
            this.mEntries = data;
            mParentDirectory = parent;
        }

        public int getCount() {
            return mEntries.length;
        }
        public Object getItem(int position) {
            return mEntries[position];
        }
        public long getItemId(int position) {
            return (long) position;
        }
        public View getView(final int position, View item, ViewGroup parent) {
            LayoutInflater factory = LayoutInflater.from(mContext);
            if (item == null) {
                item = factory.inflate(R.layout.fileant_list_item, null);
                TextView filename = (TextView) item.findViewById(R.id.filename);
                TextView fileinfo = (TextView) item.findViewById(R.id.fileinfo);
                ImageButton action = (ImageButton) item.findViewById(R.id.action);
                final String entry = mEntries[position];
                filename.setText(entry);
                boolean isDir = isDirectory(entry);
                if (isDir) {
                    fileinfo.setText("Click to view folder");
                    action.setVisibility(View.GONE);
                    item.setClickable(true);
                    item.setOnClickListener(new View.OnClickListener() {
                        public void onClick(View view) {
                            Intent intent = new Intent(FILEANT_VIEW);
                            intent.putExtra(EXTRA_CURRENT_DIRECTORY, entry);
                            intent.putExtra(EXTRA_PARENT, mParentDirectory);
                            startActivity(intent);
                        }
                    });
                } else {
                    final String type =
                        MimeTypeMap.getSingleton().getMimeTypeFromExtension(getExtension(entry));
                    fileinfo.setText(type);
                    item.setClickable(false);
                    action.setOnClickListener(new View.OnClickListener() {
                        public void onClick(View view) {
                             String filepath = entry;
                             if (!TextUtils.isEmpty(mParentDirectory)) {
                                 filepath = mParentDirectory + File.separator + filepath;
                             }
                             BufferedInputStream in = new BufferedInputStream(mManager.open(filepath));
                             // Do whatever you like with this input stream
                        }
                    });
                }
            }
            return item;
        }
     }

    /**
     * Test Whether an entry is a file or directory based on the rule:
     * File: has extension *.*, or starts with ".", which is a hidden files in Unix/Linux,
     * otherwise, it is a directory
     * @param filename
     * @return
     */
    private boolean isDirectory(String filename) {
        return !(filename.startsWith(".") || (filename.lastIndexOf(".") != -1));
    }

    private String getExtension(String filename) {
        int index = filename.lastIndexOf(".");
        if (index == -1) {
            return "";
        }
        return filename.substring(index + 1, filename.length()).toLowerCase();
    }
}