浏览文件

主类

import java.io.File;
import java.util.ArrayList;
import java.util.List;

import android.app.AlertDialog;
import android.app.Dialog;
import android.app.ListActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;

public class FileList extends ListActivity {
	
	private List<String> items = null;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle icicle) {
        super.onCreate(icicle);
        setContentView(R.layout.directory_list);
        fillWithRoot();
    }
    
    @Override
	protected void onListItemClick(ListView l, View v, int position, long id) {
		int selectionRowID = (int) getSelectedItemId();
		if (selectionRowID == 0) {
			fillWithRoot();
		} else {
			File file = new File(items.get(selectionRowID));
			if (file.isDirectory())
				fill(file.listFiles());
			else {
				Dialog dialog = new AlertDialog.Builder(this).setIcon(android.R.drawable.btn_star).setTitle("Not a Directory").setMessage(
				"That's a file, not a directory").setPositiveButton("Cancel", null).create();
				dialog.show();
			}
		}
	}

    private void fillWithRoot() {
    	fill(new File("/").listFiles());
    }

	private void fill(File[] files) {
		items = new ArrayList<String>();
		items.add(getString(R.string.to_top));
		for (File file : files)
			items.add(file.getPath());
		ArrayAdapter<String> fileList = new ArrayAdapter<String>(this, R.layout.file_row, items);
		setListAdapter(fileList);
	}
}

directory_list.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
	android:layout_width="wrap_content" android:layout_height="wrap_content">
	<ListView android:id="@id/android:list" android:layout_width="wrap_content"
		android:layout_height="wrap_content" />
	<TextView android:id="@id/android:empty" android:layout_width="wrap_content"
		android:layout_height="wrap_content" android:text="@string/no_files" />
</LinearLayout>

file_row.xml

<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
	android:id="@+id/text1" android:layout_width="wrap_content"
	android:layout_height="wrap_content" />