如何在应用程序设置中存储图像路径？

您好，我做到了，以便用户在我的应用程序中通过单击将他们定向到他们的画廊的按钮来选择个人资料图片。他们选择了图片，这很好，但是一旦我退出该应用程序或从多任务中删除，该图片就消失了。我该如何保存？我知道我需要共享首选项，但是我不确定如何在代码中使用它。我是初学者。

这是我目前在main.java上的代码。它显示了我如何使用代码从画廊中选择一张照片，但需要保存该照片：

import android.media.MediaPlayer;
import android.net.Uri;
import android.os.Bundle;
import android.provider.MediaStore;
import android.app.Activity;
import android.content.Intent;
import android.database.Cursor;
import android.graphics.BitmapFactory;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;


public class Main extends Activity {

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

{
}

        Button buttonLoadImage = (Button) findViewById(R.id.buttonLoadPicture);
        buttonLoadImage.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View arg0) {

                Intent i = new Intent(
                        Intent.ACTION_PICK,
                        android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);

                startActivityForResult(i, RESULT_LOAD_IMAGE);
            }
        });;


            Button week1 = (Button) findViewById(R.id.week1button);
            Button week2 = (Button) findViewById(R.id.week2button);
        //Button Sound
        final MediaPlayer buttonSound = MediaPlayer.create(Main.this, R.raw.sound1);


        week1.setOnClickListener(new View.OnClickListener() {

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                buttonSound.start();
                startActivity(new Intent("com.example.timetable.WEEK1"));
            }});

                week2.setOnClickListener(new View.OnClickListener(){

                    @Override
                    public void onClick(View v) {
                        // TODO Auto-generated method stub
                        buttonSound.start();
                        startActivity(new Intent("com.example.timetable.WEEK2"));
                    }
        });       

          };

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }




private static int RESULT_LOAD_IMAGE = 1;

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK && null != data) {
            Uri selectedImage = data.getData();
            String[] filePathColumn = { MediaStore.Images.Media.DATA };

            Cursor cursor = getContentResolver().query(selectedImage,
                    filePathColumn, null, null, null);
            cursor.moveToFirst();

            int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
            String picturePath = cursor.getString(columnIndex);
            cursor.close();

            ImageView imageView = (ImageView) findViewById(R.id.imageView1);
            imageView.setImageBitmap(BitmapFactory.decodeFile(picturePath));

        }


    }
}