編輯:關於android開發
使用volley進行網絡請求:需先將volley包導入androidstudio中
File下的Project Structrue,點加號導包
volley網絡請求步驟:
1. 創建請求隊列 RequestQueue queue = Volley.newRequestQueue(this);
2.創建請求對象(3種)
StringRequest request = new StringRequest(“請求方法”,“請求的網絡地址”,“成功的網絡回調”,“失敗的網絡回調”);
ImageRequest request = new ImageRequest(“圖片路徑”,“成功的回調函數”,“圖片寬度”,“圖片高度”,“圖片的顏色屬性”,“失敗的網絡回調”);
Jsonrequest request = new Jsonrequest();
3.把請求對象放入請求隊列 queue.add(request);
注銷請求:重寫onstop方法
@Override
protected void onStop() {
super.onStop();
/*取消當前請求隊列的所有請求*/
queue.cancelAll(this);
/*取消當前請求隊列tag為get的請求*/
queue.cancelAll("get");
/*取消當前請求隊列tag為post的請求*/
queue.cancelAll("post");
}
設置當前請求的優先級:重寫getPriority方法
@Override
public Priority getPriority() {
return Priority.LOW;
}
設置請求頭:重寫GetHeader方法
@Override
public Map<String, String> getHeaders() throws AuthFailureError {
Map<String,String> map = new HashMap<String, String>();
map.put("apikey","fc642e216cd19906f642ee930ce28174");
return map;
}
傳遞參數:重寫GetParams方法
@Override
protected Map<String, String> getParams() throws AuthFailureError {
Map<String,String> map = new HashMap<String, String>();
map.put("num","10");
map.put("page","1");
map.put("word","%E6%9E%97%E4%B8%B9");
return map;
}
代碼部分:
xml文件:
<?xml version="1.0" encoding="utf-8"?> <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:paddingBottom="@dimen/activity_vertical_margin" android:paddingLeft="@dimen/activity_horizontal_margin" android:paddingRight="@dimen/activity_horizontal_margin" android:paddingTop="@dimen/activity_vertical_margin" android:orientation="vertical" tools:context="com.jredu.helloworld.activity.VolleyActivity"> <WebView android:id="@+id/volleyWebView" android:layout_width="match_parent" android:layout_height="300dp"> </WebView> <ImageView android:id="@+id/img" android:layout_width="match_parent" android:layout_height="wrap_content" /> <Button android:id="@+id/volleyButton" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginTop="5dp" android:textAllCaps="false" android:text="Volley"/> <Button android:id="@+id/imgButton" android:layout_width="match_parent" android:layout_height="wrap_content" android:layout_marginTop="5dp" android:textAllCaps="false" android:text="Volley獲取圖片"/> </LinearLayout>
activity文件:
package com.jredu.helloworld.activity; import android.graphics.Bitmap; import android.os.Bundle; import android.support.v7.app.AppCompatActivity; import android.view.View; import android.webkit.WebView; import android.widget.Button; import android.widget.ImageView; import com.android.volley.AuthFailureError; import com.android.volley.NetworkResponse; import com.android.volley.ParseError; import com.android.volley.Request; import com.android.volley.RequestQueue; import com.android.volley.Response; import com.android.volley.VolleyError; import com.android.volley.toolbox.HttpHeaderParser; import com.android.volley.toolbox.ImageRequest; import com.android.volley.toolbox.StringRequest; import com.android.volley.toolbox.Volley; import com.jredu.helloworld.R; import java.io.UnsupportedEncodingException; import java.util.HashMap; import java.util.Map; public class VolleyActivity extends AppCompatActivity { WebView webView; Button button; Button imgButton; ImageView img; RequestQueue queue = null; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_volley); queue = Volley.newRequestQueue(this); webView = (WebView) findViewById(R.id.volleyWebView); img = (ImageView) findViewById(R.id.img); button = (Button) findViewById(R.id.volleyButton); button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { doStringVolley2(); doStringVolley(); } }); imgButton = (Button) findViewById(R.id.imgButton); imgButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { GetImg(); } }); } /*get方法*/ public void doStringVolley(){ /*創建請求隊列*/ //RequestQueue queue = Volley.newRequestQueue(this); /*創建請求對象*/ StringRequest request = new StringRequest( Request.Method.GET, "http://apis.baidu.com/txapi/tiyu/tiyu?num=10&page=1&word=%E6%9E%97%E4%B8%B9", /*"http://www.baidu.com",*/ new Response.Listener<String>() { @Override public void onResponse(String response) { String s = response; webView.getSettings().setDefaultTextEncodingName("utf-8"); webView.getSettings().setJavaScriptEnabled(true); webView.loadDataWithBaseURL(null,s,"text/html","utf-8",null); } }, new Response.ErrorListener() { @Override public void onErrorResponse(VolleyError error) { webView.loadDataWithBaseURL(null,"網絡連接失敗!!!","text/html","utf-8",null); } } ){ /*設置請求頭*/ @Override public Map<String, String> getHeaders() throws AuthFailureError { Map<String,String> map = new HashMap<String, String>(); map.put("apikey","fc642e216cd19906f642ee930ce28174"); return map; } /*解析網絡請求結果的方法*/ @Override protected Response<String> parseNetworkResponse( NetworkResponse response) { try { String jsonObject = new String( new String(response.data, "UTF-8")); return Response.success(jsonObject, HttpHeaderParser.parseCacheHeaders(response)); } catch (UnsupportedEncodingException e) { return Response.error(new ParseError(e)); } catch (Exception je) { return Response.error(new ParseError(je)); } } /*設置當前請求的優先級*/ @Override public Priority getPriority() { return Priority.LOW; } }; request.setTag("get"); /*把請求對象放入請求隊列*/ queue.add(request); } /*post方法*/ public void doStringVolley2(){ /*創建請求隊列*/ //RequestQueue queue = Volley.newRequestQueue(this); /*創建請求對象*/ StringRequest request = new StringRequest( Request.Method.POST, "http://www.baidu.com", new Response.Listener<String>() { @Override public void onResponse(String response) { String s = response; webView.getSettings().setDefaultTextEncodingName("utf-8"); webView.getSettings().setJavaScriptEnabled(true); webView.loadDataWithBaseURL(null,s,"text/html","utf-8",null); } }, new Response.ErrorListener() { @Override public void onErrorResponse(VolleyError error) { webView.loadDataWithBaseURL(null,"網絡連接失敗!!!","text/html","utf-8",null); } } ){ /*重寫params方法寫參數*/ @Override protected Map<String, String> getParams() throws AuthFailureError { Map<String,String> map = new HashMap<String, String>(); map.put("num","10"); map.put("page","1"); map.put("word","%E6%9E%97%E4%B8%B9"); return map; } /*設置請求對象優先級*/ @Override public Priority getPriority() { return Priority.HIGH; } }; request.setTag("post"); /*把請求對象放入請求隊列*/ queue.add(request); } /*獲取圖片*/ public void GetImg(){ ImageRequest request = new ImageRequest( "https://ss0.bdstatic.com/5aV1bjqh_Q23odCf/static/superman/img/logo/bd_logo1_31bdc765.png", new Response.Listener<Bitmap>() { @Override public void onResponse(Bitmap response) { img.setImageBitmap(response); } }, 5000, 5000, Bitmap.Config.ARGB_8888, new Response.ErrorListener() { @Override public void onErrorResponse(VolleyError error) { img.setImageResource(R.drawable.first5); } } ); queue.add(request); } /*重寫onStop方法,用來注銷請求*/ @Override protected void onStop() { super.onStop(); /*取消當前請求隊列的所有請求*/ queue.cancelAll(this); /*取消當前請求隊列tag為get的請求*/ queue.cancelAll("get"); /*取消當前請求隊列tag為post的請求*/ queue.cancelAll("post"); } }
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