1Android调用系统图库2读写文件

package com.example.demo;import android.app.Activity;import android.content.Intent;import android.database.Cursor;import android.graphics.BitmapFactory;import android.net.Uri;import android.os.Bundle;import android.provider.MediaStore;import android.view.View;import android.widget.Button;import android.widget.ImageView;public class MainActivity extends Activity {    private static int RESULT_LOAD_IMAGE = 1;/** Called when the activity is first created. */    @Override    public void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.main);                Button buttonLoadImage = (Button) findViewById(R.id.buttonLoadPicture);        buttonLoadImage.setOnClickListener(new View.OnClickListener() {@Overridepublic void onClick(View arg0) {Intent i = new Intent(Intent.ACTION_PICK,android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);startActivityForResult(i, RESULT_LOAD_IMAGE);}});    }            @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.imgView);imageView.setImageBitmap(BitmapFactory.decodeFile(picturePath));}            }}

package com.gula.tools;import java.io.FileInputStream;import java.io.FileOutputStream;import org.apache.http.util.EncodingUtils;import android.content.Context;public class FileCommon {Context context;public FileCommon(Context context) {this.context = context;}public void writeFileData(String fileName, String message) {try {FileOutputStream fout = context.openFileOutput(fileName,Context.MODE_PRIVATE);byte[] bytes = message.getBytes();fout.write(bytes);fout.close();}catch (Exception e) {e.printStackTrace();}}public String readFileData(String fileName){          String res="";          try{           FileInputStream fin = context.openFileInput(fileName);           int length = fin.available();           byte [] buffer = new byte[length];           fin.read(buffer);               res = EncodingUtils.getString(buffer, "UTF-8");           fin.close();              }          catch(Exception e){           e.printStackTrace();          }          return res;      }   }