Volly Demo之StringRequest

第一步：在MainActivity.xml中添加 interNet 权限

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

第二步：在gradle中导入依赖包

compile 'com.mcxiaoke.volley:library:1.0.19'

第三步：创建Java和XML文件

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
 >

    <Button
        android:id="@+id/start"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:text="start"
        />

    <Button
    android:id="@+id/end"
    android:layout_width="match_parent"
    android:layout_height="50dp"
    android:text="end"
    android:layout_below="@+id/start"
    />
    <Button
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:id="@+id/clear"
        android:layout_below="@+id/end"
        android:text="clear"
        />
    <Button
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:id="@+id/jump"
        android:layout_below="@+id/clear"
        android:text="jump"
        />
    <TextView
        android:id="@+id/text_view"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_below="@+id/jump"
        />
</RelativeLayout>

package homepage.yhm.com.voellydemo;

import android.app.Activity;
import android.app.DownloadManager;
import android.content.Intent;
import android.os.Handler;
import android.os.Bundle;
import android.os.Message;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

import com.android.volley.Request;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;


public class MainActivity extends Activity {

    private TextView text_view = null;
    private Button start = null;
    private Button end = null;
    private Button clear = null;
    private Button jump = null;

    //使用handler时首先要创建一个handler
    Handler handler = new Handler(){
        @Override
        public void handleMessage(Message msg) {
            text_view.setText(msg.obj.toString());
//            switch (msg.what){
//                case 1:
//                    text_view.setText(msg.obj.toString());
//                    break;
//                case 2:
//                    text_view.setText(msg.obj.toString());
//                    break;
//            }
        }
    };
    //要用handler来处理多线程可以使用runnable接口，这里先定义该接口
    //线程中运行该接口的run函数
    Runnable update_thread = new Runnable() {
        public void run() {
            //线程每次执行时输出"UpdateThread..."文字,且自动换行
            //textview的append功能和Qt中的append类似，不会覆盖前面
            //的内容，只是Qt中的append默认是自动换行模式
//            text_view.append("\nUpdateThread...");
            //延时1s后又将线程加入到线程队列中
//            handler.postDelayed(update_thread, 1000);
            //

//            StringRequest stringRequest = new StringRequest(Request.Method.GET,"http://www.baidu.com", new Response.Listener<String> (){
//                public void onResponse(String response){
//                    Message message = handler.obtainMessage();
//                    message.obj = response;
//                    message.what = 1;
//                    handler.sendMessage(message);
//                    Log.d("baidu",response);
//                };
//            }, new Response.ErrorListener() {
//                @Override
//                public void onErrorResponse(VolleyError error) {
//                    Message message = handler.obtainMessage();
//                    message.obj = error.getMessage();
//                    message.what = 2;
//                    handler.sendMessage(message);
//                }
//            });
            Volley.newRequestQueue(MainActivity.this).add(new StringRequest(Request.Method.GET,"http://www.baidu.com", new Response.Listener<String> (){
                public void onResponse(String response){
                    Message message = handler.obtainMessage();
                    message.obj = response;
                    message.what = 1;
                    handler.sendMessage(message);
                    Log.d("baidu",response);
                };
            }, new Response.ErrorListener() {
                @Override
                public void onErrorResponse(VolleyError error) {
                    Message message = handler.obtainMessage();
                    message.obj = error.getMessage();
                    message.what = 2;
                    handler.sendMessage(message);
                }
            }));



        }
    };

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        text_view = (TextView) findViewById(R.id.text_view);
        start = (Button) findViewById(R.id.start);
        start.setOnClickListener(new StartClickListener());
        end = (Button) findViewById(R.id.end);
        end.setOnClickListener(new EndClickListener());

        clear = (Button) findViewById(R.id.clear);
        clear.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                text_view.setText(null);
            }
        });

//
        jump = (Button) findViewById(R.id.jump);
        jump.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent i = new Intent();
                i.setClass(MainActivity.this, Login.class);
                startActivity(i);
            }
        });

    }

    private class StartClickListener implements View.OnClickListener {
        public void onClick(View v) {
            // TODO Auto-generated method stub
            //将线程接口立刻送到线程队列中
            handler.post(update_thread);
        }
    }

    private class EndClickListener implements View.OnClickListener {
        public void onClick(View v) {
            // TODO Auto-generated method stub
            //将接口从线程队列中移除
            handler.removeCallbacks(update_thread);
        }

    }

}