Android客户端与服务器端的json数据交互（很详细）

 Android客户端与服务器端的json数据交互，主要是通过json形式的数据交互，就是json的写入和解析。

 先看效果图，我最讨厌讲东西，一个图没有的。

算了，看来我不是写博客的材料，写不下去了，要排版之类的麻烦，大家还是直接去下载源码，里面有大量的注视，应该能看懂。 下载地址：源码下载地址

登录界面：很传统的随便做了一下：

用的是android4.0的，别人说这样的EditText很有科技感。

注册界面：

也是很传统的，文本框之类的 。

下面看看包名，类名图。（忙着和比人聊天了，差点忘了） 现在继续

客户端的：

服务器端的：

下面贴上客户端的代码：

LoginRegisterActivity.java

 <span style="font-size:18px;color:#999900;">package com.gem.hsx.activity;

 import com.gem.hsx.operation.Operaton;

 import android.app.Activity;
 import android.app.ProgressDialog;
 import android.content.Intent;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.Message;
 import android.view.View;
 import android.view.View.OnClickListener;
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.Toast;

 //此为主activity的实现登录的。在android2.3以后，android规定了主activity不允许在主线程中做一些耗时较多的
 //操作，包括网络的操作，主要是减少应用程序停止响应的问题。下面注释掉的部分是网上找到的方法，加上之后就可以在主线程中
 //进行联网操作了，但是本人采用了线程的操作，未采用该方法
 public class LoginRegisterActivity extends Activity {
     Button login;
     Button register;
     EditText etusername;
     EditText etpassword;
     String username;
     String password;
     ProgressDialog p;
     @Override
     public void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.main);

 //      StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder()
 //      .detectDiskReads()
 //      .detectDiskWrites()
 //      .detectNetwork()   // or .detectAll() for all detectable problems
 //      .penaltyLog()
 //      .build());
 //      StrictMode.setVmPolicy(new StrictMode.VmPolicy.Builder()
 //      .detectLeakedSqlLiteObjects()
 //      .penaltyLog()
 //      .penaltyDeath()
 //      .build());



         init();
         register.setOnClickListener(new RegisterOnclick());
         login.setOnClickListener(new LoginOnclick());
     }
     private void init()
     {
         etusername=(EditText) findViewById(R.id.etusername);
         etpassword=(EditText) findViewById(R.id.etpassword);
         login=(Button) findViewById(R.id.login);
         register=(Button) findViewById(R.id.register);
         p=new ProgressDialog(LoginRegisterActivity.this);
         p.setTitle("登录中");
         p.setMessage("登录中，马上就好");
     }
     private class RegisterOnclick implements OnClickListener
     {
         public void onClick(View v) {
             Intent intent=new Intent();
             intent.setClass(LoginRegisterActivity.this, Register.class);
             startActivity(intent);
         }

     }
     private class LoginOnclick implements OnClickListener
     {
         public void onClick(View arg0) {
             username=etusername.getText().toString().trim();
             if (username==null||username.length()<=0)
             {
                 etusername.requestFocus();
                 etusername.setError("对不起，用户名不能为空");
                 return;
             }
             else
             {
                 username=etusername.getText().toString().trim();
             }
             password=etpassword.getText().toString().trim();
             if (password==null||password.length()<=0)
             {
                 etpassword.requestFocus();
                 etpassword.setError("对不起，密码不能为空");
                 return;
             }
             else
             {
                 password=etpassword.getText().toString().trim();
             }
             p.show();
             new Thread(new Runnable() {

                 public void run() {
                     Operaton operaton=new Operaton();
                     String result=operaton.login("Login", username, password);
                     Message msg=new Message();
                     msg.obj=result;
                     handler.sendMessage(msg);
                 }
             }).start();

         }
     }
     Handler handler=new Handler(){
         @Override
         public void handleMessage(Message msg) {
             String string=(String) msg.obj;
             p.dismiss();
             Toast.makeText(LoginRegisterActivity.this, string, 0).show();
             super.handleMessage(msg);
         }
     };

 }</span>

Register.java

 <span style="font-size:18px;">package com.gem.hsx.activity;

 import java.io.File;
 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.InputStream;
 import java.util.ArrayList;
 import java.util.List;

 import com.gem.hsx.bean.User;
 import com.gem.hsx.json.WriteJson;
 import com.gem.hsx.operation.Operaton;

 import android.app.Activity;
 import android.app.AlertDialog;
 import android.app.Dialog;
 import android.app.ProgressDialog;
 import android.content.DialogInterface;
 import android.content.Intent;
 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
 import android.net.Uri;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.Message;
 import android.view.View;
 import android.view.View.OnClickListener;
 import android.view.View.OnFocusChangeListener;
 import android.widget.Button;
 import android.widget.EditText;
 import android.widget.ImageView;
 import android.widget.RadioButton;
 import android.widget.Toast;


 public class Register extends Activity {
     Button submit;
     Button select;
     EditText etusername;
     EditText etpassword;
     RadioButton ckman;
     RadioButton ckwoman;
     EditText etage;
     ImageView imgphoto;
     String str;
     String filepath=null;
     String jsonString=null;
     ProgressDialog dialog;
     private static final int REQUEST_EX = 1;
     String username=null;
     String password=null;
     String sex=null;
     String age=null;
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.register);
         init();
         //etusername.addTextChangedListener(new MyTextWatcher());
         etusername.setOnFocusChangeListener(new EtusernameOnFocusChange());
         select.setOnClickListener(new SelectOnclick());
         submit.setOnClickListener(new SubmitOnclick());
     }
     private void init()
     {
         submit=(Button) findViewById(R.id.submit);
         select=(Button) findViewById(R.id.select);
         etusername=(EditText) findViewById(R.id.etusername);
         etpassword=(EditText) findViewById(R.id.etpassword);
         ckman=(RadioButton) findViewById(R.id.ckman);
         ckwoman=(RadioButton) findViewById(R.id.ckwoman);
         etage=(EditText) findViewById(R.id.etage);
         imgphoto=(ImageView) findViewById(R.id.imgphoto);
         dialog=new ProgressDialog(Register.this);
         dialog.setTitle("上传数据中");
         dialog.setMessage("请稍等...");
     }

     //  private   class MyTextWatcher implements TextWatcher
     //  {
     //
     //      public void afterTextChanged(Editable s) {
     //           str=etusername.getText().toString().trim();
     //           if (str==null||str.length()<=0)
     //           {
     //              etusername.setError("用户名不能为空");
     //           }
     //           else
     //           {
     //               new Thread(new Runnable() {
     //
     //                  public void run() {
     //                       Operaton operaton=new Operaton();
     //                       String result= operaton.checkusername("Check", str);
     //                       Message message=new Message();
     //                       message.obj=result;
     //                       handler.sendMessage(message);
     //                  }
     //              }).start();
     //
     //
     //            }
     //      }
     //      public void beforeTextChanged(CharSequence s, int start, int count,
     //              int after) {
     //
     //      }
     //
     //      public void onTextChanged(CharSequence s, int start, int before,
     //              int count) {
     //
     //      }
     //
     //  }
     //  Handler handler=new Handler()
     //  {
     //      @Override
     //      public void handleMessage(Message msg) {
     //          String msgobj=msg.obj.toString();
     //          if (msgobj=="该用户名可用")
     //          {
     //              etusername.setFocusable(false);
     //          }
     //          else
     //          {
     //              etusername.requestFocus();
     //              etusername.setError(msgobj);
     //          }
     //          super.handleMessage(msg);
     //      }
     //  };
     //
     private class EtusernameOnFocusChange implements OnFocusChangeListener
     {
         public void onFocusChange(View v, boolean hasFocus) {
             if (!etusername.hasFocus()) {
                 str=etusername.getText().toString().trim();
                 if (str==null||str.length()<=0)
                 {
                     etusername.setError("用户名不能为空");
                 }
                 else
                 {
                     new Thread(new Runnable() {
                  //如果用户名不为空，那么将用户名提交到服务器上进行验证，看用户名是否存在，就像JavaEE中利用
                 //ajax一样，虽然你看不到但是它却偷偷摸摸做了很多
                         public void run() {
                             Operaton operaton=new Operaton();
                             String result= operaton.checkusername("Check", str);
                             System.out.println("result:"+result);
                             Message message=new Message();
                             message.obj=result;
                             handler.sendMessage(message);
                         }
                     }).start();
                 }
             }
         }
     }
     Handler handler=new Handler()
     {
         @Override
         public void handleMessage(Message msg) {
             String msgobj=msg.obj.toString();
             System.out.println(msgobj);
             System.out.println(msgobj.length());

             if (msgobj.equals("t")) {
                 etusername.requestFocus();
                 etusername.setError("用户名"+str+"已存在");
             }
             else
             {
                 etpassword.requestFocus();
             }
             super.handleMessage(msg);
         }
     };
     private class SelectOnclick implements OnClickListener
     {
         public void onClick(View v) {

             Intent intent = new Intent();
             intent.putExtra("explorer_title",
                     getString(R.string.dialog_read_from_dir));
             intent.setDataAndType(Uri.fromFile(new File("/sdcard")), "*/*");
             intent.setClass(Register.this, ExDialog.class);
             startActivityForResult(intent, REQUEST_EX);
         }
     }
     protected void onActivityResult(int requestCode, int resultCode,
             Intent intent) {
         if (resultCode == RESULT_OK) {

             Uri uri = intent.getData();
             filepath=uri.toString().substring(6);
             System.out.println(filepath);
             //用户的头像是不是图片格式
             if(filepath.endsWith("jpg")||filepath.endsWith("png"))
             {
                 File file=new File(filepath);
                 try {
                     InputStream inputStream=new FileInputStream(file);
                     Bitmap bitmap = BitmapFactory.decodeStream(inputStream);
                     imgphoto.setImageBitmap(bitmap);//如果是就将图片显示出来
                 } catch (FileNotFoundException e) {
                     e.printStackTrace();
                 }
                 submit.setClickable(true);
             }
             else
             {
                 submit.setClickable(false);
                 alert();
             }

         }
     }

     private class SubmitOnclick implements OnClickListener
     {
         public void onClick(View v) {
             username=etusername.getText().toString().trim();
             password=etpassword.getText().toString().trim();

             if (ckman.isChecked()) {
                 sex="男";
             }
             else {
                 sex="女";
             }
             age=etage.getText().toString().trim();
             if (age==null||age.length()<=0)
             {
                 etage.requestFocus();
                 etage.setError("年龄不能为空");
                 return ;
             }

             dialog.show();
             new Thread(new Runnable() {

                 public void run() {

                     Operaton operaton=new Operaton();
                     File file=new File(filepath);
                     String photo=operaton.uploadFile(file, "ImgReciver");
                     //先进行图片上传的操作，然后服务器返回图片保存在服务器的路径，
                     System.out.println("photo---->"+photo);
                     System.out.println("sex:------>"+sex);
                     User user=new User(username, password, sex, age,photo);
                     //构造一个user对象
                     List<User> list=new ArrayList<User>();
                     list.add(user);
                     WriteJson writeJson=new WriteJson();
                     //将user对象写出json形式字符串
                     jsonString= writeJson.getJsonData(list);
                     System.out.println(jsonString);
                     String result= operaton.UpData("Register", jsonString);
                     Message msg=new Message();
                     System.out.println("result---->"+result);
                     msg.obj=result;
                     handler1.sendMessage(msg);
                 }
             }).start();

         }
     }
     private void alert()
     {
         Dialog dialog = new AlertDialog.Builder(this)
         .setTitle("提示")
         .setMessage("您选择的不是有效的图片")
         .setPositiveButton("确定",
                 new DialogInterface.OnClickListener() {
             public void onClick(DialogInterface dialog,
                     int which) {
                 filepath = null;
             }
         })
         .create();
         dialog.show();
     }
     Handler handler1=new Handler()
     {
         @Override
         public void handleMessage(Message msg) {
             dialog.dismiss();
             String msgobj=msg.obj.toString();
             if(msgobj.equals("t"))
             {
                 Toast.makeText(Register.this, "注册成功", 0).show();
                 Intent intent=new Intent();
                 intent.setClass(Register.this, LoginRegisterActivity.class);
                 startActivity(intent);
             }
             else {
                 Toast.makeText(Register.this, "注册失败", 0).show();
             }
             super.handleMessage(msg);
         }
     };
 }</span>

ExDialog.java

 package com.gem.hsx.activity;


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


 import android.app.ListActivity;
 import android.content.Context;
 import android.content.Intent;
 import android.net.Uri;
 import android.os.Bundle;
 import android.util.Log;
 import android.view.Display;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 import android.view.WindowManager;
 import android.view.WindowManager.LayoutParams;
 import android.widget.BaseAdapter;
 import android.widget.ImageView;
 import android.widget.ListView;
 import android.widget.TextView;


 import com.gem.hsx.activity.R;
 //由于安卓模拟器里面没有文件浏览器，所以构建一个文件浏览器的对话框 主要是dialog和listview配合
 //此是一个简单的浏览器主要目的是选择文件后获取文件的路径，借鉴了一些其他人的文件浏览器的写法
 public class ExDialog extends ListActivity {
     private List<Map<String, Object>> mData;
     private String mDir = "/sdcard";


     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);


         Intent intent = this.getIntent();
         Bundle bl = intent.getExtras();
         String title = bl.getString("explorer_title");
         Uri uri = intent.getData();
         mDir = uri.getPath();


         setTitle(title);
         mData = getData();
         MyAdapter adapter = new MyAdapter(this);
         setListAdapter(adapter);


         WindowManager m = getWindowManager();
         Display d = m.getDefaultDisplay();
         LayoutParams p = getWindow().getAttributes();
         p.height = (int) (d.getHeight() * 0.8);
         p.width = (int) (d.getWidth() * 0.95);
         getWindow().setAttributes(p);
     }


     private List<Map<String, Object>> getData() {
         List<Map<String, Object>> list = new ArrayList<Map<String, Object>>();
         Map<String, Object> map = null;
         File f = new File(mDir);
         File[] files = f.listFiles();


         if (!mDir.equals("/sdcard")) {
             map = new HashMap<String, Object>();
             map.put("title", "返回上一级目录/");
             map.put("info", f.getParent());
             map.put("img", R.drawable.ex_folder);
             list.add(map);
         }
         if (files != null) {
             for (int i = 0; i < files.length; i++) {
                 map = new HashMap<String, Object>();
                 map.put("title", files[i].getName());
                 map.put("info", files[i].getPath());
                 if (files[i].isDirectory())
                     map.put("img", R.drawable.ex_folder);
                 else
                     map.put("img", R.drawable.ex_doc);
                 list.add(map);
             }
         }
         return list;
     }


     @Override
     protected void onListItemClick(ListView l, View v, int position, long id) {
         Log.d("MyListView4-click", (String) mData.get(position).get("info"));
         if ((Integer) mData.get(position).get("img") == R.drawable.ex_folder) {
             mDir = (String) mData.get(position).get("info");
             mData = getData();
             MyAdapter adapter = new MyAdapter(this);
             setListAdapter(adapter);
         } else {
             finishWithResult((String) mData.get(position).get("info"));
         }
     }


     public final class ViewHolder {
         public ImageView img;
         public TextView title;
         public TextView info;
     }


     public class MyAdapter extends BaseAdapter {
         private LayoutInflater mInflater;


         public MyAdapter(Context context) {
             this.mInflater = LayoutInflater.from(context);
         }


         public int getCount() {
             return mData.size();
         }


         public Object getItem(int arg0) {
             return null;
         }


         public long getItemId(int arg0) {
             return 0;
         }


         public View getView(int position, View convertView, ViewGroup parent) {
             ViewHolder holder = null;
             if (convertView == null) {
                 holder = new ViewHolder();
                 convertView = mInflater.inflate(R.layout.listview, null);
                 holder.img = (ImageView) convertView.findViewById(R.id.img);
                 holder.title = (TextView) convertView.findViewById(R.id.title);
                 //  holder.info = (TextView) convertView.findViewById(R.id.info);
                 convertView.setTag(holder);
             } else {
                 holder = (ViewHolder) convertView.getTag();
             }


             holder.img.setBackgroundResource((Integer) mData.get(position).get(
             "img"));
             holder.title.setText((String) mData.get(position).get("title"));
             //holder.info.setText((String) mData.get(position).get("info"));
             return convertView;
         }
     }


     private void finishWithResult(String path) {
         Bundle conData = new Bundle();
         conData.putString("results", "Thanks Thanks");
         Intent intent = new Intent();
         intent.putExtras(conData);
         Uri startDir = Uri.fromFile(new File(path));
         intent.setDataAndType(startDir,
         "vnd.android.cursor.dir/lysesoft.andexplorer.file");
         setResult(RESULT_OK, intent);
         finish();
     }
 };

JsonUtil.java

 <pre name="code" class="java">package com.gem.hsx.json;


 import java.lang.reflect.Type;
 import java.util.ArrayList;
 import java.util.List;
 import com.google.gson.Gson;
 import com.google.gson.reflect.TypeToken;




 public class JsonUtil {
     public List<?> StringFromJson (String jsondata)
     {
         Type listType = new TypeToken<List<?>>(){}.getType();
         Gson gson=new Gson();
         ArrayList<?> list=gson.fromJson(jsondata, listType);
         return list;


     }
 }</pre><br>
 <pre></pre>
 <p></p>
 WriteJson.java
 <p><span style="font-size:18px"></span></p>
 <pre name="code" class="java">package com.gem.hsx.json;

 import java.util.List;
 import com.google.gson.Gson;

 public class WriteJson {
     /*
      * 通过引入gson jar包 写入 json 数据
      */
     public String getJsonData(List<?> list)
     {
 //此处要注意，时常会出现说找不到Gson类的情况，这时我们只需要将导入的包和系统提供换换顺序就行了
         Gson gson=new Gson();//利用google提供的gson将一个list集合写成json形式的字符串
         String jsonstring=gson.toJson(list);
         return jsonstring;
     }
     /*
      * 当然如果不用gson也可以用传统的方式进行写入json数据或者利用StringBuffer拼字符串 写成json字符串形式
      */
 }</pre><br>
 <br>
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 <p></p>
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 <pre></pre>
 <pre></pre>