andriod 缩略图Thumbnails学习

?

/**

 * @(#)MainActivity.java

 *

 * Copyright XXX.All rights reserved.

 * This software is the XXX system.

 *

 * @Version: XXX

 * @JDK: jdk 1.6.0.XXX

 * @Module: androidThumbnail

 */

 /*-        History

 **********************************************

 *  ID      DATE           PERSON       REASON

 *  1     2012-7-11    WuChaoWen    Created

 **********************************************

 */

 

package com.example.androidthumbnail;

 

import java.io.File;

import java.io.FileInputStream;

import java.io.InputStream;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

 

 

import android.R.bool;

import android.R.integer;

import android.annotation.SuppressLint;

import android.app.Activity;

import android.app.Dialog;

import android.content.ContentResolver;

import android.content.Context;

import android.content.Intent;

import android.database.Cursor;

import android.graphics.Bitmap;

import android.graphics.BitmapFactory;

import android.net.Uri;

import android.os.Bundle;

import android.provider.MediaStore;

import android.provider.MediaStore.Images.Media;

import android.provider.MediaStore.Images.Thumbnails;

import android.util.Log;

import android.view.View;

import android.view.Window;

import android.view.View.OnClickListener;

import android.widget.AdapterView;

import android.widget.AdapterView.OnItemClickListener;

import android.widget.Button;

import android.widget.GridView;

import android.widget.ImageView;

import android.widget.ListAdapter;

import android.widget.SimpleAdapter;

import android.widget.Toast;

 

/**

 * Class description goes here.

 * @author WuChaoWen

 * @since 2012-7-11

 */

public class MainActivity extends Activity {

     public static String TAG = "Thumbnails";  

     public static boolean flag = true;

     ImageView ivImageShow;

        private GridView gridView;  

        private ArrayList<HashMap<String, String>> list;  

        private ContentResolver cr; 

        private ArrayList<String> fileList ;

        public void onCreate(Bundle savedInstanceState) {

            requestWindowFeature(Window.FEATURE_NO_TITLE);//去除标题

            super.onCreate(savedInstanceState);

            setContentView(R.layout.main); 

            findViews();

    }

         

         

        @SuppressLint("ParserError")

        private void findViews() {  

            ivImageShow = (ImageView)this.findViewById(R.id.ivImageShow);

            gridView = (GridView) findViewById(R.id.gridview);  

            list = new ArrayList<HashMap<String, String>>();  

            fileList = new ArrayList<String>();

            cr = getContentResolver();  

            String[] projection = { Thumbnails._ID, Thumbnails.IMAGE_ID,  

                    Thumbnails.DATA};   //所要查询的字段

            Cursor cursor = cr.query(Thumbnails.EXTERNAL_CONTENT_URI, projection,  

                    null, null, null);  

             

            getColumnData(cursor);  

        //    changeFile();

            String[] from = { "path" };  

            int[] to = { R.id.ItemImage };  

            ListAdapter adapter = new GridAdapter(this, list, R.layout.item, from,to);  

            gridView.setAdapter(adapter);  

            gridView.setOnItemClickListener(listener);  

           

        }  

         

         

        public Uri[] uriArray;

        private void getColumnData(Cursor cur) {  

            if (cur.moveToFirst()) {  

                int _id;  

                int image_id;  

                String image_path;  

                int _idColumn = cur.getColumnIndex(Thumbnails._ID);  

                int image_idColumn = cur.getColumnIndex(Thumbnails.IMAGE_ID);  

                int dataColumn = cur.getColumnIndex(Thumbnails.DATA);  

                do {  

                    // Get the field values  

                    _id = cur.getInt(_idColumn);  

                    image_id = cur.getInt(image_idColumn);  

                    image_path = cur.getString(dataColumn);  

                    // Do something with the values.  

                    Log.i(TAG, _id + " image_id:" + image_id + " path:" 

                            + image_path + "---");  

                    HashMap hash = new HashMap();  

                    hash.put("image_id", image_id + "");  

                    hash.put("path", image_path);  

                    list.add(hash);  

       

                    //根据image_id获取真实路径

                   String path = getFileByImageId(image_id);

                  fileList.add(path);

                } while (cur.moveToNext());  

       

            }  

        } 

         

         

        OnItemClickListener listener = new OnItemClickListener() {  

               

            @Override 

            public void onItemClick(AdapterView<?> parent, View view, int position,  

                    long id) {  

                // TODO Auto-generated method stub  

            //1.获取选定图片的path

                String path = "";

                String image_id = list.get(position).get("image_id");  

                Log.i(TAG, "---(^o^)----" + image_id);  

                String[] projection = { Media._ID, Media.DATA };  

                Cursor cursor = cr.query(Media.EXTERNAL_CONTENT_URI, projection,  

                        Media._ID + "=" + image_id, null, null);  

                if (cursor != null) {  

                    cursor.moveToFirst();  

                     path = cursor.getString(cursor  

                            .getColumnIndex(Media.DATA));  

                     Log.i("path:", path);

                } else {  

                    Toast.makeText(MainActivity.this, "Image doesn't exist!",  

                            Toast.LENGTH_SHORT).show();  

                }  

                 

                 

                //2.以一个对话框来显示图片

                 

                // TODO Auto-generated method stub

                final Dialog dialog = new Dialog(MainActivity.this);

                // 以对话框形式显示图片

                dialog.setContentView(R.layout.image_show);

                dialog.setTitle("图片显示");

 

                ImageView ivImageShow = (ImageView) dialog.findViewById(R.id.ivImageShow);

                Button btnClose = (Button) dialog.findViewById(R.id.btnClose);

 

                btnClose.setOnClickListener(new OnClickListener() {

                     

                    @Override

                    public void onClick(View v) {

                        dialog.dismiss();

                    }

                     

                });

                 

                Uri uri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI.buildUpon().

                          appendPath(Long.toString(id)).build();

                FileUtil file = new FileUtil();

                ContentResolver resolver = getContentResolver();

                InputStream inputStream = null; 

 

 

                // 从Uri中读取图片资源

                try {

                    inputStream = new FileInputStream(path); 

                    Bitmap bitmap = BitmapFactory.decodeStream(inputStream); 

                    ivImageShow.setImageBitmap(bitmap);

                } catch (Exception e) {

                    // TODO: handle exception

                    e.printStackTrace();

                }

 

                dialog.show();

       

            }  

        };  

         

         

         

        class GridAdapter extends SimpleAdapter {  

               

            public GridAdapter(Context context,  

                    List<? extends Map<String, ?>> data, int resource,  

                    String[] from, int[] to) {  

                super(context, data, resource, from, to);  

                

            }  

       

            // set the imageView using the path of image  

            public void setViewImage(ImageView v, String value) {  

                try {  

                    Bitmap bitmap = BitmapFactory.decodeFile(value);  

                    Bitmap newBit = Bitmap  

                            .createScaledBitmap(bitmap, 100, 80, true);  

                    v.setImageBitmap(newBit);  

                } catch (NumberFormatException nfe) {  

                    v.setImageURI(Uri.parse(value));  

                }  

            }  

        }  

         

         

          

        //整理缩略图的uri转成file并归类

        public String getFileByImageId(int image_id){

             

            String path = "";

            

            Log.i(TAG, "---(^o^)----" + image_id);  

            String[] projection = { Media._ID, Media.DATA };  

            Cursor cursor2 = cr.query(Media.EXTERNAL_CONTENT_URI, projection,  

                    Media._ID + "=" + image_id, null, null);  

            if (cursor2 != null) {  

                cursor2.moveToFirst();  

                 path = cursor2.getString(cursor2  

                        .getColumnIndex(Media.DATA));  

                 Log.i("path:", path);

            } else {  

                Toast.makeText(MainActivity.this, "Image doesn't exist!",  

                        Toast.LENGTH_SHORT).show();  

            }    

             

            return path;

        }

}