Volley框架

Volley框架

volley是谷歌官方在2013年推出的Android平台上的网络通信库

特点

• 网络通信更快,更简单，开发效率高，稳定性高。
• 对get和post网络请求以及网络图片高效的异步处理请求。
• 可以对网络请求进行优先级排序处理。
• 网络请求的缓存。
• 多级别取消请求。
• 和Activity生命周期的联动。

缺点
不适合数据的上传与下载

---

Get和Post请求接口的使用
请求对象

• StringRequest 返回结果类型不确定(它包含后面两种)

1. StringRequest request =newStringRequest(Request.Method.GET, REQUEST_URL,newResponse.Listener<String>(){
2. @Override
3. publicvoid onResponse(String s){//数据请求成功
4. result.setText("请求成功:"+ s);
5. }
6. },newResponse.ErrorListener(){
7. @Override
8. publicvoid onErrorResponse(VolleyError volleyError){//数据请求失败
9. result.setText("请求失败:"+ volleyError.getMessage());
10. }
11. });

• JsonObjectRequest

1. JSONObject jsonRequest =newJSONObject();//Get请求传递参数jsonRequest可以为空null
2. JsonObjectRequest request =newJsonObjectRequest(Request.Method.GET, REQUEST_URL,null,newResponse.Listener<JSONObject>(){
3. @Override
4. publicvoid onResponse(JSONObject jsonObject){
5. result.setText("请求成功:"+ jsonObject);
6. }
7. },newResponse.ErrorListener(){
8. @Override
9. publicvoid onErrorResponse(VolleyError volleyError){
10. result.setText("请求失败:"+ volleyError.getMessage());
11. }
12. });

• JsonArrayRequest

1. JsonArrayRequest request =newJsonArrayRequest(REQUEST_URL,newResponse.Listener<JSONArray>(){
2. @Override
3. publicvoid onResponse(JSONArray jsonArray){
4. result.setText("请求成功:"+ jsonArray);
5. }
6. },newResponse.ErrorListener(){
7. @Override
8. publicvoid onErrorResponse(VolleyError volleyError){
9. result.setText("请求失败:"+ volleyError.getMessage());
10. }
11. });

---

网络请求队列建立和取消队列建立

• 建立一个全局的请求队列。

1. //创建请求队列
2. privatestaticRequestQueue queues;
3. //初始化请求队列
4. queues =Volley.newRequestQueue(getApplicationContext());

• 建立一个请求并加入队列中。

1. MyApplication.getQueues().add(request);

• 取消队列

1. MyApplication.getQueues().cancelAll(tag);

---

与Activity生命周期的联动

• 可以在Activity销毁的同时关闭请求。
• 设置Tag标签，在onStop()里执行取消请求。

1. @Override
2. protectedvoid onStop(){
3. super.onStop();
4. //结束请求
5. MyApplication.getQueues().cancelAll("StringRequest_get");
6. }

---

Volley调用实例源码展示

demo效果如下

• 布局文件

1. <?xml version="1.0" encoding="utf-8"?>
2. <LinearLayout
3. xmlns:android="http://schemas.android.com/apk/res/android"
4. xmlns:tools="http://schemas.android.com/tools"
5. android:id="@+id/activity_main"
6. android:layout_width="match_parent"
7. android:layout_height="match_parent"
8. android:orientation="vertical"
9. tools:context="com.xhb.app.MainActivity"
10. >
12. <ScrollView
13. android:layout_width="match_parent"
14. android:layout_height="match_parent">
16. <LinearLayout
17. android:layout_width="match_parent"
18. android:layout_height="match_parent"
19. android:orientation="vertical">
21. <RelativeLayout
22. android:layout_width="match_parent"
23. android:layout_height="wrap_content"
24. android:gravity="center">
26. <Button
27. android:id="@+id/_StringRequestGet"
28. android:layout_width="wrap_content"
29. android:layout_height="wrap_content"
30. android:onClick="StringRequestGet"
31. android:text="StringRequestGet"
32. android:textAllCaps="false"/>
34. <Button
35. android:id="@+id/StringRequestPost"
36. android:layout_width="wrap_content"
37. android:layout_height="wrap_content"
38. android:layout_marginLeft="20dp"
39. android:layout_toRightOf="@id/_StringRequestGet"
40. android:onClick="StringRequestPost"
41. android:text="StringRequestPost"
42. android:textAllCaps="false"/>
43. </RelativeLayout>
45. <RelativeLayout
46. android:layout_width="match_parent"
47. android:layout_height="wrap_content"
48. android:gravity="center">
50. <Button
51. android:id="@+id/JsonObjectRequestGet"
52. android:layout_width="wrap_content"
53. android:layout_height="wrap_content"
54. android:onClick="JsonObjectRequestGet"
55. android:text="JsonObjectRequestGet"
56. android:textAllCaps="false"/>
58. <Button
59. android:id="@+id/JsonObjectRequestPost"
60. android:layout_width="wrap_content"
61. android:layout_height="wrap_content"
62. android:layout_marginLeft="20dp"
63. android:layout_toRightOf="@id/JsonObjectRequestGet"
64. android:onClick="JsonObjectRequestPost"
65. android:text="JsonObjectRequestPost"
66. android:textAllCaps="false"/>
67. </RelativeLayout>
69. <RelativeLayout
70. android:layout_width="match_parent"
71. android:layout_height="wrap_content"
72. android:gravity="center">
74. <Button
75. android:id="@+id/JsonArrayRequest"
76. android:layout_width="wrap_content"
77. android:layout_height="wrap_content"
78. android:layout_alignParentLeft="true"
79. android:layout_alignParentStart="true"
80. android:layout_alignParentTop="true"
81. android:onClick="JsonArrayRequest"
82. android:text="JsonArrayRequest"
83. android:textAllCaps="false"/>
84. </RelativeLayout>
86. <RelativeLayout
87. android:layout_width="match_parent"
88. android:layout_height="wrap_content"
89. android:gravity="center">
91. <Button
92. android:id="@+id/MyRequestGet"
93. android:layout_width="wrap_content"
94. android:layout_height="wrap_content"
95. android:onClick="MyRequestGet"
96. android:text="MyRequestGet"
97. android:textAllCaps="false"/>
99. <Button
100. android:id="@+id/MyRequestPost"
101. android:layout_width="wrap_content"
102. android:layout_height="wrap_content"
103. android:layout_marginLeft="20dp"
104. android:layout_toRightOf="@id/MyRequestGet"
105. android:onClick="MyRequestPost"
106. android:text="MyRequestPost"
107. android:textAllCaps="false"/>
108. </RelativeLayout>
110. <RelativeLayout
111. android:layout_width="match_parent"
112. android:layout_height="wrap_content"
113. android:gravity="center">
115. <Button
116. android:id="@+id/ImageRequest"
117. android:layout_width="wrap_content"
118. android:layout_height="wrap_content"
119. android:onClick="ImageRequest"
120. android:text="ImageRequest"
121. android:textAllCaps="false"/>
123. <Button
124. android:id="@+id/ImageLoader"
125. android:layout_width="wrap_content"
126. android:layout_height="wrap_content"
127. android:layout_marginLeft="20dp"
128. android:layout_toRightOf="@id/ImageRequest"
129. android:onClick="ImageLoader"
130. android:text="ImageLoader"
131. android:textAllCaps="false"/>
132. </RelativeLayout>
134. <RelativeLayout
135. android:layout_width="match_parent"
136. android:layout_height="wrap_content"
137. android:gravity="center">
139. <ImageView
140. android:id="@+id/image_imageRequest"
141. android:layout_width="100dp"
142. android:layout_height="100dp"
143. android:src="@mipmap/ic_launcher"
144. android:textAllCaps="false"/>
146. <ImageView
147. android:id="@+id/image_iamgeLoader"
148. android:layout_width="100dp"
149. android:layout_height="100dp"
150. android:layout_marginLeft="20dp"
151. android:layout_toRightOf="@id/image_imageRequest"
152. android:src="@mipmap/ic_launcher"
153. android:textAllCaps="false"/>
154. </RelativeLayout>
156. <TextView
157. android:layout_width="match_parent"
158. android:layout_height="wrap_content"
159. android:layout_marginTop="20dp"
160. android:text="请求结果为:"/>
162. <TextView
163. android:id="@+id/result"
164. android:layout_width="match_parent"
165. android:layout_height="0dp"
166. android:layout_weight="1"/>
167. </LinearLayout>
168. </ScrollView>
169. </LinearLayout>

• 全局初始化文件

1. publicclassMyApplicationextendsApplication{
2. //创建请求队列
3. privatestaticRequestQueue queues;
4. @Override
5. publicvoid onCreate(){
6. super.onCreate();
7. //初始书请求队列
8. queues =Volley.newRequestQueue(getApplicationContext());
9. }
10. publicstaticRequestQueue getQueues(){
11. return queues;
12. }
13. }

• 主要实现文件

1. publicclassMainActivityextendsAppCompatActivity{
3. publicstaticfinalString BASE ="http://op.juhe.cn/onebox/weather/query";
4. publicstaticfinalString REQUEST_URL = BASE +"?cityname=%E5%8D%81%E5%A0%B0&key=634f562a2b3900e051c6af6e2dc3017e";
5. publicstaticfinalString IMAGE_URL ="https://pic.cnblogs.com/avatar/789527/20160825180355.png";
6. privateTextView result;
7. privateImageView image_imageRequest, image_iamgeLoader;
9. @Override
10. protectedvoid onCreate(Bundle savedInstanceState){
11. super.onCreate(savedInstanceState);
12. setContentView(R.layout.activity_main);
13. result =(TextView) findViewById(R.id.result);
14. image_imageRequest =(ImageView) findViewById(R.id.image_imageRequest);
15. image_iamgeLoader =(ImageView) findViewById(R.id.image_iamgeLoader);
16. }
18. publicvoidStringRequestGet(View view){
19. //StringRequest
20. StringRequest request =newStringRequest(Request.Method.GET, REQUEST_URL,newResponse.Listener<String>(){
21. @Override
22. publicvoid onResponse(String s){//数据请求成功
23. result.setText("请求成功:"+ s);
24. }
25. },newResponse.ErrorListener(){
26. @Override
27. publicvoid onErrorResponse(VolleyError volleyError){//数据请求失败
28. result.setText("请求失败:"+ volleyError.getMessage());
29. }
30. });
31. request.setTag("StringRequest_get");
32. MyApplication.getQueues().add(request);
33. }
36. publicvoidStringRequestPost(View view){
37. //StringRequest
38. StringRequest request =newStringRequest(Request.Method.POST, BASE,newResponse.Listener<String>(){
39. @Override
40. publicvoid onResponse(String s){//数据请求成功
41. result.setText("请求成功:"+ s);
42. }
43. },newResponse.ErrorListener(){
44. @Override
45. publicvoid onErrorResponse(VolleyError volleyError){//数据请求失败
46. result.setText("请求失败:"+ volleyError.getMessage());
47. }
48. }){
49. @Override//传递参数
50. protectedMap<String,String> getParams()throwsAuthFailureError{
51. Map<String,String> map =newHashMap<>();
52. map.put("key","634f562a2b3900e051c6af6e2dc3017e");
53. map.put("cityname","十堰");
54. return map;
55. }
56. };
57. request.setTag("StringRequestPost");
58. MyApplication.getQueues().add(request);
59. }
61. publicvoidJsonObjectRequestGet(View view){
62. //JsonObjectRequest
63. JSONObject jsonRequest =newJSONObject();//Get请求传递参数jsonRequest可以为空null
64. JsonObjectRequest request =newJsonObjectRequest(Request.Method.GET, REQUEST_URL,null,newResponse.Listener<JSONObject>(){
65. @Override
66. publicvoid onResponse(JSONObject jsonObject){
67. result.setText("请求成功:"+ jsonObject);
68. }
69. },newResponse.ErrorListener(){
70. @Override
71. publicvoid onErrorResponse(VolleyError volleyError){
72. result.setText("请求失败:"+ volleyError.getMessage());
73. }
74. });
75. request.setTag("JsonObjectRequestGet");
76. MyApplication.getQueues().add(request);
77. }
79. publicvoidJsonObjectRequestPost(View view){
80. Map<String,String> map =newHashMap<>();
81. map.put("key","634f562a2b3900e051c6af6e2dc3017e");
82. map.put("cityname","十堰");
83. JSONObject jsonRequest =newJSONObject(map);
84. JsonObjectRequest request =newJsonObjectRequest(Request.Method.POST, BASE, jsonRequest,newResponse.Listener<JSONObject>(){
85. @Override
86. publicvoid onResponse(JSONObject jsonObject){
87. result.setText("请求成功:"+ jsonObject.toString());
88. }
89. },newResponse.ErrorListener(){
90. @Override
91. publicvoid onErrorResponse(VolleyError volleyError){
92. result.setText("请求失败:"+ volleyError.getMessage());
93. }
94. });
95. request.setTag("JsonObjectRequestPost");
96. MyApplication.getQueues().add(request);
97. }
99. publicvoidJsonArrayRequest(View view){
100. JsonArrayRequest request =newJsonArrayRequest(REQUEST_URL,newResponse.Listener<JSONArray>(){
101. @Override
102. publicvoid onResponse(JSONArray jsonArray){
103. result.setText("请求成功:"+ jsonArray);
104. }
105. },newResponse.ErrorListener(){
106. @Override
107. publicvoid onErrorResponse(VolleyError volleyError){
108. result.setText("请求失败:"+ volleyError.getMessage());
109. }
110. });
111. request.setTag("JsonArrayRequest");
112. MyApplication.getQueues().add(request);
113. }
115. publicvoidMyRequestGet(View view){
116. newVolleyRequest().RequestGet(this, REQUEST_URL,"MyRequestGet",newResultBack(this,ResultBack.listener,ResultBack.errorListener){
117. @Override
118. publicvoid onSuccess(String s){
119. result.setText("请求成功:"+ s);
120. }
122. @Override
123. publicvoid onFailure(VolleyError volleyError){
124. result.setText("请求失败:"+ volleyError.getMessage());
125. }
126. });
127. }
129. publicvoidMyRequestPost(View view){
130. Map<String,String> map =newHashMap<>();
131. map.put("key","634f562a2b3900e051c6af6e2dc3017e");
132. map.put("cityname","十堰");
133. newVolleyRequest().RequestPost(this, REQUEST_URL,"MyRequestPost", map,newResultBack(this,ResultBack.listener,ResultBack.errorListener){
134. @Override
135. publicvoid onSuccess(String s){
136. result.setText("请求成功:"+ s);
137. }
139. @Override
140. publicvoid onFailure(VolleyError volleyError){
141. result.setText("请求失败:"+ volleyError.getMessage());
142. }
143. });
144. }
146. //ImageRequest方式加载图片
147. publicvoidImageRequest(View view){
148. ImageRequest request =newImageRequest(IMAGE_URL,newResponse.Listener<Bitmap>(){
149. @Override
150. publicvoid onResponse(Bitmap bitmap){//加载成功
151. image_imageRequest.setImageBitmap(bitmap);
152. }
153. },0,0,Bitmap.Config.RGB_565,newResponse.ErrorListener(){//加载失败
154. @Override
155. publicvoid onErrorResponse(VolleyError volleyError){
156. image_imageRequest.setImageResource(R.mipmap.ic_launcher);
157. }
158. });
159. request.setTag("ImageRequest");
160. MyApplication.getQueues().add(request);
161. }
163. //ImageLoader加载图片
164. publicvoidImageLoader(View view){
165. ImageLoader imageLoader =newImageLoader(MyApplication.getQueues(),newBitmapCache());
166. ImageLoader.ImageListener listener = imageLoader.getImageListener(image_iamgeLoader, R.mipmap.ic_launcher, R.mipmap.ic_launcher);
167. imageLoader.get(IMAGE_URL, listener);
168. }
170. @Override
171. protectedvoid onStop(){
172. super.onStop();
173. //结束请求
174. MyApplication.getQueues().cancelAll("StringRequest_get");
175. }
176. }

• Volley简单的二次回调封装

1. publicclassVolleyRequest{
2. publicstaticStringRequest stringRequest;
3. publicstaticvoidRequestGet(Context context,String url,String tag,ResultBack reback){
4. MyApplication.getQueues().cancelAll(tag);
5. stringRequest=newStringRequest(Request.Method.GET, url,reback.loadingListener(),reback.errorListener());
6. stringRequest.setTag(tag);
7. MyApplication.getQueues().add(stringRequest);
8. MyApplication.getQueues().start();
9. }
10. publicstaticvoidRequestPost(Context context,String url,String tag,finalMap<String,String> map,ResultBack reback){
11. MyApplication.getQueues().cancelAll(tag);
12. stringRequest=newStringRequest(Request.Method.GET, url, reback.loadingListener(),reback.errorListener()){
13. @Override
14. protectedMap<String,String> getParams()throwsAuthFailureError{
15. return map;
16. }
17. };
18. stringRequest.setTag(tag);
19. MyApplication.getQueues().add(stringRequest);
20. MyApplication.getQueues().start();
21. }
22. }

自定义的回调接口

1. publicabstractclassResultBack{
2. publicContext context;
3. publicstaticResponse.Listener<String> listener;
4. publicstaticResponse.ErrorListener errorListener;
6. publicResultBack(Context context,Response.Listener<String> listener,Response.ErrorListener errorListener){
7. this.context = context;
8. this.listener = listener;
9. this.errorListener = errorListener;
10. }
12. publicResponse.Listener<String> loadingListener(){
13. listener =newResponse.Listener<String>(){
14. @Override
15. publicvoid onResponse(String s){
16. onSuccess(s);
17. }
18. };
19. return listener;
20. }
22. publicResponse.ErrorListener errorListener(){
23. errorListener =newResponse.ErrorListener(){
24. @Override
25. publicvoid onErrorResponse(VolleyError volleyError){
26. onFailure(volleyError);
27. }
28. };
29. return errorListener;
30. }
32. publicabstractvoid onSuccess(String s);
33. publicabstractvoid onFailure(VolleyError volleyError);
34. }

• 图像缓存类

1. publicclassBitmapCacheimplementsImageLoader.ImageCache{
2. publicLruCache<String,Bitmap> mBitmapLruCache;
3. publicint max=1024*1024*10;// 最大缓存10M,超过就会回收
5. publicBitmapCache(){
6. mBitmapLruCache=newLruCache<String,Bitmap>(max){
7. @Override
8. protectedint sizeOf(String key,Bitmap value){
9. return value.getRowBytes()*value.getHeight();
10. }
11. };
12. }
14. @Override
15. publicBitmap getBitmap(String s){
16. return mBitmapLruCache.get(s);
17. }
19. @Override
20. publicvoid putBitmap(String s,Bitmap bitmap){
21. mBitmapLruCache.put(s,bitmap);
22. }
23. }

来自为知笔记(Wiz)