Java-android使用GridView布局的电子相册&服务器获取图片

转  http://www.tuicool.com/articles/B7JNv2

电子相册的思路：

1.先是考虑布局，我用的是GridView布局

2.GridView中又该怎么显示图片，其实我的这个应用每个图片都是同一个布局，首先要实现适配器接口，再利用充气泵LayoutInflater把布局文件转换成View视图对象

3.怎么从服务器获取图片，又是怎么捉去到的

有思路不等于你会了，直接给你上代码吧：

首先介绍下我的应用的功能：

1.显示的每一张图片，点击后都可以显示出单独的一张，并且是全屏

2.如果点击其中的任意一张图片长时间，会弹出窗口，显示这张图片的基本的信息

不足：

1.现在存在获取资源过多，内存溢出的bug，后期我会处理，可以选择把图片保存到本地，不全部从服务器获取

2.功能不够强大，我还会用另一个布局，把电子相册的效果呈现处理

MainActivity.java源码：

package com.example.photo;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.AdapterView.OnItemLongClickListener;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.ProgressBar;
import android.widget.TextView;

/**
 * 2013-6-15 下午12:54:56
 *
 * @author 乔晓松
 */
public class MainActivity extends Activity {

  protected static final int TEXT = 0;
  protected static final int ACTIVITY = 1;
  public GridView gridView;
  public int id;
  public Handler handler;
  public static Object[] path; // = { "span.jpg", "span1.jpg", "span2.jpg",
                  // "span3.jpeg", "psb.jpeg", "psbpan.jpeg"
                  // };
  public String basePath = "http://172.22.64.6:8080/lession08_image/images/";
  public List<Map<String, Object>> datas;
  public LayoutInflater inflater;
  public Map<String, Integer> fileMap;
  public ProgressBar progressBar;

  @SuppressLint({ "HandlerLeak", "CutPasteId" })
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    gridView = (GridView) findViewById(R.id.gridView1);
    progressBar = (ProgressBar) findViewById(R.id.progressBar1);
    progressBar.setVisibility(View.VISIBLE);
    inflater = (LayoutInflater) this
        .getSystemService(LAYOUT_INFLATER_SERVICE);
    datas = new ArrayList<Map<String, Object>>();
    fileMap = new HashMap<String, Integer>();

    handler = new Handler() {
      @Override
      public void handleMessage(Message msg) {
        super.handleMessage(msg);
        switch (msg.what) {
        case TEXT:
          progressBar.setVisibility(View.GONE);
          gridView.setAdapter(new MyListAdapter());
          break;
        default:
          break;
        }
      }
    };
    new Thread(new Runnable() {

      @Override
      public void run() {
        List<String> list = HttpClientTool
            .httpClientJSON("http://172.22.64.6:8080/lession08_image/csdn/ImagesAction_httpAllImages.action");
        if (list != null) {
          path = list.toArray();
        }
        for (int i = 0; i < path.length; i++) {
          Map<String, Object> map = new HashMap<String, Object>();
          Map<String, Object> bitmap = HttpClientTool.send(
              MainActivity.this, basePath + path[i]);
          if (map != null) {
            map.put("img", (Bitmap) (bitmap.get("img")));
            map.put("name", path[i]);
            datas.add(map);
          }
          fileMap.put(path[i].toString(),
              (Integer) (bitmap.get("length")));
        }
        handler.sendEmptyMessage(TEXT);
      }
    }).start();

    gridView.setOnItemClickListener(new OnItemClickListener() {

      @Override
      public void onItemClick(AdapterView<?> parent, View view,
          int position, long id) {
        Integer length = fileMap.get(path[position]);
        Intent intent = new Intent(MainActivity.this,
            ImageActivity.class);
        intent.putExtra("id", position);
        intent.putExtra("basepath", basePath);
        intent.putExtra("path", path);
        intent.putExtra("length", length);
        startActivity(intent);
      }
    });
    gridView.setOnItemLongClickListener(new OnItemLongClickListener() {

      @Override
      public boolean onItemLongClick(AdapterView<?> parent, View view,
          int position, long id) {
        Integer length = fileMap.get(path[position]);
        new AlertDialog.Builder(MainActivity.this)
            .setTitle("图片信息")
            .setMessage(
                "图片名称：" + path[position] + "\n图片大小：" + length
                    + "k").show();
        return false;
      }
    });
  }

  @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;
  }

  class MyListAdapter extends BaseAdapter {

    @Override
    public int getCount() {
      return datas.size();
    }

    @Override
    public Object getItem(int position) {
      return datas.get(position);
    }

    @Override
    public long getItemId(int position) {
      return position;
    }

    @Override
public View getView(int position, View convertView, ViewGroup parent) {
  View v = inflater.inflate(R.layout.grid_item, null);
  ImageView tx_name = (ImageView) v.findViewById(R.id.ItemImage);
  TextView tx_phone = (TextView) v.findViewById(R.id.ItemText);
  Map<String, Object> map = datas.get(position);
  tx_name.setImageBitmap((Bitmap) map.get("img"));
  tx_phone.setText((String) map.get("name"));
return v;
  }

  }
}

下面这个类就是点击任意一张图片，开启意图Intent，Create另一个Activity，就是单独一个图片的页面

package com.example.photo;

import java.util.Map;

import android.annotation.SuppressLint;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.view.Menu;
import android.widget.ImageView;
import android.widget.RelativeLayout;

/**
 * 2013-6-16 下午8:23:54
 *
 * @author 乔晓松
 */
public class ImageActivity extends Activity {

  public static final int IMG = 0;
  public Handler handler;

  public RelativeLayout relativeLayout = null;
  public ImageView imageView;
  public int length;
  public int id;
  public Object[] path;

  @SuppressLint({ "HandlerLeak", "NewApi" })
  @Override
  protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    handler = new Handler() {
      @Override
      public void handleMessage(Message msg) {
        super.handleMessage(msg);
        switch (msg.what) {
        case IMG:
          if (relativeLayout != null) {
            ImageActivity.this.setContentView(relativeLayout);
          }
          break;

        default:
          break;
        }
      }
    };
    new Thread(new Runnable() {

      @Override
      public void run() {
        Intent intent = ImageActivity.this.getIntent();
        Bundle bundle = intent.getExtras();
        id = bundle.getInt("id");
        length = bundle.getInt("length");
        String basePath = bundle.getString("basepath");
        path = (Object[]) bundle.get("path");
        relativeLayout = new RelativeLayout(ImageActivity.this);
        imageView = new ImageView(ImageActivity.this);
        Map<String, Object> bitmap = HttpClientTool.send(
            ImageActivity.this, basePath + path[id].toString());
        imageView.setImageBitmap((Bitmap) bitmap.get("img"));
        imageView.setMaxWidth(300);
        imageView.setMaxHeight(400);
        relativeLayout.addView(imageView);

        handler.sendEmptyMessage(IMG);
      }
    }).start();
    /*
     * imageView.setOnLongClickListener(new OnLongClickListener() {
     *
     * @Override public boolean onLongClick(View v) { // new
     * AlertDialog.Builder
     * (ImageActivity.this).setTitle("图片信息").setMessage("图片名称："
     * +path[id]+"\n\t图片大小："+length+"k").show(); return false; } });
     */
  }

  @Override
  public boolean onCreateOptionsMenu(Menu menu) {
    return super.onCreateOptionsMenu(menu);
  }
}

下面的这个类是我自己写的一个工具类，用户发送请求或者获取图片

package com.example.photo;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.UnsupportedEncodingException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.annotation.SuppressLint;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.widget.ImageView;
import android.widget.Toast;

/**
 * 2013-6-19 上午9:44:41
 *
 * @author 乔晓松
 */
public class HttpClientTool {

  // 获取图片以及图片的信息
  @SuppressWarnings("unused")
  @SuppressLint("NewApi")
  public static Map<String, Object> send(Context context, String path) {
    Map<String, Object> map = new HashMap<String, Object>();
    ImageView imageView = null;
    imageView = new ImageView(context);
    imageView.setMaxHeight(100);
    imageView.setMaxWidth(100);
    Bitmap bitmap = null;
    try {
      URL url = new URL(path);
      HttpURLConnection httpURLConnection = (HttpURLConnection) url
          .openConnection();
      httpURLConnection.setRequestMethod("GET");
      httpURLConnection.setConnectTimeout(5000);
      if (httpURLConnection.getResponseCode() == 200) {
        if (bitmap != null) {
          System.out.println("---"+bitmap);
          bitmap.recycle();
          System.gc();
        }
        InputStream is = httpURLConnection.getInputStream();
        bitmap = BitmapFactory.decodeStream(is);
//				BitmapFactory.Options options = new BitmapFactory.Options();
//				options.inSampleSize = computeSampleSize(options, -1, 128*128);
//				options.inJustDecodeBounds = true;
        int length = httpURLConnection.getContentLength();
        // System.out.println(httpURLConnection.get);
        // MediaStore
        map.put("img", bitmap);
        map.put("length", length);
      } else {
        Toast.makeText(context, "服务器端响应错误", Toast.LENGTH_LONG).show();
      }
      httpURLConnection.disconnect();
    } catch (MalformedURLException e) {
      e.printStackTrace();
    } catch (IOException e) {
      e.printStackTrace();
    }
    return map;

  }

  public static int computeSampleSize(BitmapFactory.Options options,
      int minSideLength, int maxNumOfPixels) {
    int initialSize = computeInitialSampleSize(options, minSideLength,
        maxNumOfPixels);
    int roundedSize;
    if (initialSize <= 8) {
      roundedSize = 1;
      while (roundedSize < initialSize) {
        roundedSize <<= 1;
      }
    } else {
      roundedSize = (initialSize + 7) / 8 * 8;
    }
    return roundedSize;
  }

  public static int computeInitialSampleSize(BitmapFactory.Options options,
      int minSideLength, int maxNumOfPixels) {
    double w = options.outWidth;
    double h = options.outHeight;
    int lowerBound = (maxNumOfPixels == -1) ? 1 : (int) Math.ceil(Math
        .sqrt(w * h / maxNumOfPixels));
    int upperBound = (minSideLength == -1) ? 128 : (int) Math.min(
        Math.floor(w / minSideLength), Math.floor(h / minSideLength));
    if (upperBound < lowerBound) {
      // return the larger one when there is no overlapping zone.
      return lowerBound;
    }
    if ((maxNumOfPixels == -1) && (minSideLength == -1)) {
      return 1;
    } else if (minSideLength == -1) {
      return lowerBound;
    } else {
      return upperBound;
    }
  }

  // 获取服务器端images文件下的所有图片名称
  public static List<String> httpClientJSON(String path) {
    List<String> list = null;
    try {
      list = new ArrayList<String>();
      HttpGet httpGet = new HttpGet(path);
      HttpClient httpClient = new DefaultHttpClient();
      HttpResponse httpResponse = httpClient.execute(httpGet);
      if (httpResponse.getStatusLine().getStatusCode() == 200) {
        StringBuilder builder = new StringBuilder();
        BufferedReader bufferedReader = new BufferedReader(
            new InputStreamReader(httpResponse.getEntity()
                .getContent()));
        String str = null;
        while ((str = bufferedReader.readLine()) != null) {
          builder.append(str);
        }
        JSONObject jsonObject = new JSONObject(builder.toString());
        JSONArray jsonArray = jsonObject.getJSONArray("list");
        for (int i = 0; i < jsonArray.length(); i++) {
          Object obj = jsonArray.opt(i);
          list.add(obj.toString());
          System.out.println(obj.toString());
        }
      }
    } catch (UnsupportedEncodingException e) {
      e.printStackTrace();
    } catch (ClientProtocolException e) {
      e.printStackTrace();
    } catch (IOException e) {
      e.printStackTrace();
    } catch (JSONException e) {
      e.printStackTrace();
    }
    return list;
  }
}

//

这么多代码写出来了，要是没有授权还是不行的，必须有网络权限

<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
    <uses-permission android:name="android.permission.INTERNET"/>

布局文件

GridView布局

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <ProgressBar
        android:id="@+id/progressBar1"
        style="?android:attr/progressBarStyleLarge"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_centerHorizontal="true"
        android:layout_marginTop="160dp" />

    <GridView
        android:id="@+id/gridView1"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:numColumns="3"
        tools:ignore="AdapterViewChildren,UselessParent" >
    </GridView>

</RelativeLayout>

单个图片的布局

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:paddingBottom="4dip" >

    <ImageView
        android:id="@+id/ItemImage"
        android:layout_width="85dp"
        android:layout_height="85dp"
        android:layout_centerHorizontal="true"
        tools:ignore="ContentDescription" >
    </ImageView>

    <TextView
        android:id="@+id/ItemText"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@+id/ItemImage"
        android:layout_centerHorizontal="true" >
    </TextView>

</RelativeLayout>

ProgressBar是加载数据时的一个加载效果