Added simple file chooser dialog,

This is to select game iso when creating homescreen shortcut.

Probably not an ideal solution, could use ppsspp internal GameBrowser later.

android/src/org/ppsspp/ppsspp/SimpleFileChooser.java

@@ -0,0 +1,112 @@
+package org.ppsspp.ppsspp;
+
+import java.io.File;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Comparator;
+import java.util.List;
+
+import android.app.Activity;
+import android.app.AlertDialog;
+import android.content.DialogInterface;
+import android.os.Environment;
+
+/**
+ * Simple dialog to pick file. 
+ * TODO: Use GameBrowser from MainScreen.cpp instead. Then remove this class.
+ */
+public class SimpleFileChooser {
+
+	public interface FileSelectedListener {
+		void onFileSelected(File file);
+	}
+
+	private FileSelectedListener mFileListener;
+
+	private final Activity mActivity;
+	private static final String PARENT_DIR = "..";
+	private String[] mFileList;
+	private File mCurrentPath;
+
+	public SimpleFileChooser(Activity activity, File path,
+			FileSelectedListener listener) {
+		this.mActivity = activity;
+		this.mFileListener = listener;
+		if (!path.exists())
+			path = Environment.getExternalStorageDirectory();
+		rebuildFileList(path);
+	}
+
+	public void showDialog() {
+		AlertDialog.Builder builder = new AlertDialog.Builder(mActivity);
+		builder.setTitle(mCurrentPath.getPath());
+		// populate dialog with list of files and directories.
+		builder.setItems(mFileList, onDialogItemClickedListener);
+		builder.show();
+	}
+
+	// Create list of files and directories.
+	private void rebuildFileList(File path) {
+		this.mCurrentPath = path;
+		List<String> r = new ArrayList<String>();
+
+		if (path.getParentFile() != null)
+			r.add(PARENT_DIR);
+
+		File[] fileList = path.listFiles();
+		if (fileList != null) {
+			Arrays.sort(fileList, fileArrayComparator);
+			for (File file : fileList) {
+				r.add(file.getName());
+			}
+		}
+		mFileList = (String[]) r.toArray(new String[0]);
+	}
+
+	// Get selected file, dir, or parent dir.
+	private File getSelectedFile(String selectedFileName) {
+		if (selectedFileName.equals(PARENT_DIR))
+			return mCurrentPath.getParentFile();
+		else
+			return new File(mCurrentPath, selectedFileName);
+	}
+
+	// Comparator for Arrays.sort(). Separate folders from files, order
+	// alphabetically, ignore case.
+	private Comparator<File> fileArrayComparator = new Comparator<File>() {
+		public int compare(File file1, File file2) {
+			if (file1 == null || file2 == null) // if either null, assume equal
+				return 0;
+			// put folder first before file
+			else if (file1.isDirectory() && (!file2.isDirectory()))
+				return -1;
+			else if (file2.isDirectory() && (!file1.isDirectory()))
+				return 1;
+			else
+				// when both are folders or both are files, sort by name
+				return file1.getName().toUpperCase()
+						.compareTo(file2.getName().toUpperCase());
+		}
+	};
+
+	// Event when user click item on dialog
+	private DialogInterface.OnClickListener onDialogItemClickedListener = new DialogInterface.OnClickListener() {
+		public void onClick(DialogInterface dialog, int which) {
+			String selectedFileName = mFileList[which];
+			File selectedFile = getSelectedFile(selectedFileName);
+
+			// always remove previous dlg first
+			dialog.cancel();
+			dialog.dismiss();
+
+			if (selectedFile.isDirectory()) {
+				rebuildFileList(selectedFile);
+				showDialog(); // create new dlg
+			} else {
+				if (mFileListener != null)
+					mFileListener.onFileSelected(selectedFile);
+			}
+		}
+	};
+
+}