sharepreference方式保存带图片的例子
2通常，Sharepreference方式保存数据只能保存简单类型的数据，对于像图片等，就需要对这些数据进行编码，然后将编码后的数据按字符串的形式保存到xml中去。本项目需要用到一个第三方的jar包（common-codec-1.4.jar）在选择图片的时候我们采用画廊视图来选择一张图片。核心代码如下：package net.blogjava.mobile; import java.io.ByteArrayInputStream;import java.io.ByteArrayOutputStream;import java.io.ObjectInputStream;import java.io.ObjectOutputStream;import java.lang.reflect.Field;import java.util.ArrayList;import java.util.List; import org.apache.commons.codec.binary.Base64; import android.app.Activity;import android.app.AlertDialog;import android.content.Context;import android.content.DialogInterface;import android.content.SharedPreferences;import android.content.res.TypedArray;import android.graphics.Bitmap.CompressFormat;import android.graphics.drawable.BitmapDrawable;import android.graphics.drawable.Drawable;import android.os.Bundle;import android.view.View;import android.view.View.OnClickListener;import android.view.ViewGroup;import android.widget.BaseAdapter;import android.widget.Button;import android.widget.EditText;import android.widget.Gallery;import android.widget.ImageView; public class Main extends Activity implements OnClickListener{ private SharedPreferences mySharedPreferences; private EditText etProductID; private EditText etProductName; private EditText etProductPrice; private ImageView imageView; private List<Integer> imageResIdList = new ArrayList<Integer>(); public class ImageAdapter extends BaseAdapter { int mGalleryItemBackground; private Context mContext; public ImageAdapter(Context context) { mContext = context; TypedArray typedArray = obtainStyledAttributes(R.styleable.Gallery1); mGalleryItemBackground = typedArray.getResourceId( R.styleable.Gallery1_android_galleryItemBackground, 0); } public int getCount() { return imageResIdList.size(); } public Object getItem(int position) { return position; } public long getItemId(int position) { return position; } public View getView(int position, View convertView, ViewGroup parent) { ImageView imageView = new ImageView(mContext); imageView.setImageResource(imageResIdList.get(position)); imageView.setScaleType(ImageView.ScaleType.FIT_XY); imageView.setLayoutParams(new Gallery.LayoutParams(136, 88)); imageView.setBackgroundResource(mGalleryItemBackground); return imageView; } } @Override public void onClick(View view) { try { switch (view.getId()) { case R.id.btnSave: Product product = new Product(); product.setId(etProductID.getText().toString()); product.setName(etProductName.getText().toString()); product.setPrice(Float.parseFloat(etProductPrice.getText() .toString())); ByteArrayOutputStream baos = new ByteArrayOutputStream(); ObjectOutputStream oos = new ObjectOutputStream(baos); oos.writeObject(product); mySharedPreferences = getSharedPreferences("base64", Activity.MODE_PRIVATE); String productBase64 = new String(Base64.encodeBase64(baos .toByteArray())); SharedPreferences.Editor editor = mySharedPreferences .edit(); editor.putString("product", productBase64); baos = new ByteArrayOutputStream(); ((BitmapDrawable) imageView.getDrawable()).getBitmap() .compress(CompressFormat.JPEG, 50, baos); String imageBase64 = new String(Base64.encodeBase64(baos .toByteArray())); editor.putString("productImage", imageBase64); editor.commit(); oos.close(); new AlertDialog.Builder(this).setTitle("保存成功.") .setPositiveButton("确定", null).show(); break; case R.id.btnSelectImage: View myView = getLayoutInflater().inflate(R.layout.gallery, null); final Gallery gallery = (Gallery) myView .findViewById(R.id.gallery); ImageAdapter imageAdapter = new ImageAdapter(this); gallery.setAdapter(imageAdapter); new AlertDialog.Builder(this) .setTitle("选择产品图像") .setView(myView) .setPositiveButton( "确定", new android.content.DialogInterface.OnClickListener() { @Override public void onClick( DialogInterface dialog, int which) { imageView .setImageResource(imageResIdList .get(gallery .getSelectedItemPosition())); } }).setNegativeButton("取消", null).show(); break; } } catch (Exception e) { setTitle("error:" + e.getMessage()); } } @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); Button btnSave = (Button) findViewById(R.id.btnSave); Button btnSelectImage = (Button) findViewById(R.id.btnSelectImage); etProductID = (EditText) findViewById(R.id.etProductID); etProductName = (EditText) findViewById(R.id.etProductName); etProductPrice = (EditText) findViewById(R.id.etProductPrice); imageView = (ImageView) findViewById(R.id.imageview); btnSave.setOnClickListener(this); btnSelectImage.setOnClickListener(this); byte[] base64Bytes; ByteArrayInputStream bais; try { mySharedPreferences = getSharedPreferences("base64", Activity.MODE_PRIVATE); String productBase64 = mySharedPreferences.getString("product", ""); base64Bytes = Base64.decodeBase64(productBase64.getBytes()); bais = new ByteArrayInputStream(base64Bytes); ObjectInputStream ois = new ObjectInputStream(bais); Product product = (Product) ois.readObject(); etProductID.setText(product.getId()); etProductName.setText(product.getName()); etProductPrice.setText(String.valueOf(product.getPrice())); ois.close(); } catch (Exception e) { } try { String imageBase64 = mySharedPreferences.getString("productImage", ""); base64Bytes = Base64.decodeBase64(imageBase64.getBytes()); bais = new ByteArrayInputStream(base64Bytes); imageView.setImageDrawable(Drawable.createFromStream(bais, "product_image")); Field[] fields = R.drawable.class.getDeclaredFields(); for (Field field : fields) { if (!"icon".equals(field.getName())) imageResIdList.add(field.getInt(R.drawable.class)); } } catch (Exception e) { // TODO: handle exception } }}</div
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