Volley的Get、Post方式（JsonObjectRequest、StringRequest）以及Volley获取图片的3种方式

activity_main.xml 里面什么也没有

AndroidManifest.xml（重点是android:name="com.example.volley.MyApplication"）

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="com.example.volley"

    android:versionCode="1"

    android:versionName="1.0" >

    <uses-sdk

        android:minSdkVersion="18"

        android:targetSdkVersion="18" />

    <application

        android:name="com.example.volley.MyApplication"

        android:allowBackup="true"

        android:icon="@drawable/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme" >

        <activity

            android:name=".MainActivity"

            android:label="@string/app_name" >

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

    </application>

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

</manifest>

MyApplication

package com.example.volley;

import com.android.volley.RequestQueue;

import com.android.volley.toolbox.Volley;

import android.app.Application;

public class MyApplication extends Application {

	public static RequestQueue queue;

	/** 一旦创建就创建RequestQueue请求队列 */

	@Override

	public void onCreate() {

		super.onCreate();

		queue = Volley.newRequestQueue(getApplicationContext());

	}

	/** 对外提供静态的方法 */

	public static RequestQueue getHttpRequestQueue() {

		return queue;

	}

}

MainActivity

package com.example.volley;

import java.io.File;

import java.io.FileInputStream;

import java.io.InputStream;

import java.util.HashMap;

import java.util.Map;

import org.json.JSONObject;

import com.android.volley.Request.Method;

import com.android.volley.AuthFailureError;

import com.android.volley.Response;

import com.android.volley.Response.Listener;

import com.android.volley.VolleyError;

import com.android.volley.toolbox.JsonObjectRequest;

import com.android.volley.toolbox.StringRequest;

import android.app.Activity;

import android.os.Bundle;

import android.util.Log;

import android.widget.Toast;

public class MainActivity extends Activity {

	/**

	 * 关联activity。退出之后取消全部的网络请求，释放资源

	 */

	@Override

	protected void onStop() {

		super.onStop();

		MyApplication.getHttpRequestQueue().cancelAll("abcGet");

	}

	@Override

	protected void onCreate(Bundle savedInstanceState) {

		super.onCreate(savedInstanceState);

		setContentView(R.layout.activity_main);

//		volley_get();

		volley_post();

	}

	/**

	 * get请求方式

	 */

	private void volley_get() {

		/**

		 * String类型

		 */

		String url = "http://www.imooc.com/api/teacher?

type=4&num=30";

		StringRequest request = new StringRequest(Method.GET, url,

				new Listener<String>() {

					@Override

					public void onResponse(String arg0) {

						//返回正确后的操作

						Log.e("TAG", ""+arg0);

					}

				}, new Response.ErrorListener() {

					@Override

					public void onErrorResponse(VolleyError arg0) {

					}

				});

		// 设置标签

		request.setTag("abcGet");

		MyApplication.getHttpRequestQueue().add(request);

		MyApplication.getHttpRequestQueue().start();

		/**

		 * JsonObjectRequest类型 由于get參数已经在url写好了，所以传空就可以

		 */

		JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(Method.GET,

				url, null, new Listener<JSONObject>() {

					@Override

					public void onResponse(JSONObject arg0) {

						Toast.makeText(MainActivity.this, arg0.toString(), 0)

								.show();

					}

				}, new Response.ErrorListener() {

					@Override

					public void onErrorResponse(VolleyError arg0) {

					}

				});

		// 设置标签

		jsonObjectRequest.setTag("bcdGet");

		MyApplication.getHttpRequestQueue().add(jsonObjectRequest);

		MyApplication.getHttpRequestQueue().start();

		/**

		 * 还有jsonArray方式,这里省略了。。。

		 */

	}

	/**

	 * post请求方式

	 */

	private void volley_post() {

		/**

		 * StringRequest---post方式

		 */

		String url = "http://www.imooc.com/api/teacher?

";

		StringRequest request = new StringRequest(Method.POST, url,

				new Listener<String>() {

					@Override

					public void onResponse(String arg0) {

						Log.e("TAG", ""+arg0);

					}

				}, new Response.ErrorListener() {

					@Override

					public void onErrorResponse(VolleyError arg0) {

					}

				}) {

			@Override

			protected Map<String, String> getParams() throws AuthFailureError {

				//传递參数

				Map<String, String> map = new HashMap<String, String>();

				map.put("type", "4");

				map.put("num", "30");

				return map;

			}

		};

		// 设置标签

		request.setTag("abcPost");

		MyApplication.getHttpRequestQueue().add(request);

		MyApplication.getHttpRequestQueue().start();

		/**

		 * jsonObject--post方式

		 */

		HashMap<String, String> map = new HashMap<String, String>();

		map.put("type", "4");

		map.put("num", "30");

		// 将map转为jsonObject对象

		JSONObject object = new JSONObject(map);

		JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(Method.POST, url,

				object, new Listener<JSONObject>() {

					@Override

					public void onResponse(JSONObject arg0) {

						Log.e("TAG", arg0.toString());

					}

				}, new Response.ErrorListener() {

					@Override

					public void onErrorResponse(VolleyError arg0) {

					}

				});

		// 设置标签

		jsonObjectRequest.setTag("bcdPost");

		MyApplication.getHttpRequestQueue().add(jsonObjectRequest);

		MyApplication.getHttpRequestQueue().start();

	}

}

*************************************************下载网络图片**********************************************

AndroidManifest.xml（重点是 android:name="com.example.volleyimagedemo.MyApplication"）

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="com.example.volleyimagedemo"

    android:versionCode="1"

    android:versionName="1.0" >

    <uses-sdk

        android:minSdkVersion="18"

        android:targetSdkVersion="18" />

    <application

        android:name="com.example.volleyimagedemo.MyApplication"

        android:allowBackup="true"

        android:icon="@drawable/ic_launcher"

        android:label="@string/app_name"

        android:theme="@style/AppTheme" >

        <activity

            android:name=".MainActivity"

            android:label="@string/app_name" >

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

    </application>

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

</manifest>

activity_main.xml

<LinearLayout 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:orientation="vertical"

    tools:context="com.example.volleyimagedemo.MainActivity" >

    <!-- 方式一 -->

    <ImageView

        android:id="@+id/imageview1"

        android:layout_width="fill_parent"

        android:layout_height="wrap_content" />

     <!-- 方式二 -->

    <ImageView

        android:id="@+id/imageview2"

        android:layout_width="fill_parent"

        android:layout_height="wrap_content" />

    <!-- 方式三 -->

    <com.android.volley.toolbox.NetworkImageView

        android:id="@+id/networkImageview"

        android:layout_width="fill_parent"

        android:layout_height="wrap_content" >

    </com.android.volley.toolbox.NetworkImageView>

</LinearLayout>

MyApplication

package com.example.volleyimagedemo;

import com.android.volley.RequestQueue;

import com.android.volley.toolbox.Volley;

import android.app.Application;

public class MyApplication extends Application {

	public static RequestQueue queue;

	@Override

	public void onCreate() {

		super.onCreate();

		queue = Volley.newRequestQueue(getApplicationContext());

	}

	public static RequestQueue getHttpRequestQueue() {

		return queue;

	}

}

BitMapCache

package com.example.volleyimagedemo;

import android.graphics.Bitmap;

import android.util.LruCache;

import com.android.volley.toolbox.ImageLoader.ImageCache;

public class BitMapCache implements ImageCache{

	public LruCache<String, Bitmap> cache;

	//超过10兆，自己主动回收

	public int max = 10*1024*1024;

	public BitMapCache(){

		cache = new LruCache<String, Bitmap>(max){

			@Override

			protected int sizeOf(String key, Bitmap value) {

				return value.getRowBytes()*value.getHeight();

			}

		};

	}

	@Override

	public Bitmap getBitmap(String arg0) {

		return cache.get(arg0);

	}

	@Override

	public void putBitmap(String arg0, Bitmap arg1) {

		cache.put(arg0, arg1);

	}

}

MainActivity

package com.example.volleyimagedemo;

import android.app.Activity;

import android.graphics.Bitmap;

import android.graphics.Bitmap.Config;

import android.os.Bundle;

import android.widget.ImageView;

import com.android.volley.Response;

import com.android.volley.Response.Listener;

import com.android.volley.VolleyError;

import com.android.volley.toolbox.ImageLoader;

import com.android.volley.toolbox.ImageLoader.ImageListener;

import com.android.volley.toolbox.ImageRequest;

import com.android.volley.toolbox.NetworkImageView;

public class MainActivity extends Activity {

	private ImageView imageview1;

	private ImageView imageview2;

	private NetworkImageView networkImageView;

	@Override

	protected void onCreate(Bundle savedInstanceState) {

		super.onCreate(savedInstanceState);

		setContentView(R.layout.activity_main);

		/** 获取控件、图片url地址 */

		imageview1 = (ImageView) findViewById(R.id.imageview1);

		imageview2 = (ImageView) findViewById(R.id.imageview2);

		networkImageView = (NetworkImageView) findViewById(R.id.networkImageview);

		String url = "http://img.mukewang.com/55237dcc0001128c06000338-300-170.jpg";

		/**

		 * 下载图片的另外一种方式ImageLoader+BitMapCache

		 */

		// imageCache单肚使用是不到缓存效果，须要结合lruCache

		ImageLoader imageLoader1 = new ImageLoader(

				MyApplication.getHttpRequestQueue(), new BitMapCache());

		networkImageView.setDefaultImageResId(R.drawable.ic_launcher);

		networkImageView.setErrorImageResId(R.drawable.ic_launcher);

		networkImageView.setImageUrl(url, imageLoader1);

		/**

		 * 下载图片的第三种种方式

		 */

		ImageLoader imageLoader2 = new ImageLoader(

				MyApplication.getHttpRequestQueue(), new BitMapCache());

		// view视图，默认的图片，错误的图片

		ImageListener listener = imageLoader1.getImageListener(imageview2,

				R.drawable.ic_launcher, R.drawable.ic_launcher);

		imageLoader2.get(url, listener);

		/**

		 * 下载网络图片的第一种方式ImageRequest

		 */

		// // 0 是原图的方式载入--Config.RGB_565原图

		ImageRequest imageRequest = new ImageRequest(url,

				new Listener<Bitmap>() {

					//

					@Override

					public void onResponse(Bitmap arg0) {

						imageview1.setImageBitmap(arg0);

					}

				}, 0, 0, Config.RGB_565, new Response.ErrorListener() {

					@Override

					public void onErrorResponse(VolleyError arg0) {

						imageview1

								.setBackgroundResource(R.drawable.ic_launcher);

					}

				});

		MyApplication.getHttpRequestQueue().add(imageRequest);

		MyApplication.getHttpRequestQueue().start();

	}

}

巴特西

Volley的Get、Post方式（JsonObjectRequest、StringRequest）以及Volley获取图片的3种方式

最新文章

热门文章