我正在尝试制作的音乐播放器中使用Volley。
下面是我如何定义音乐播放器中的歌曲。我有一个带有一些属性的“歌曲对象”
SongObject {
public String albumArtURI;
// Some other attributes
}
我使用albumArtURI用图像填充各种列表和网格视图。
要获取专辑ArtURI,我对其进行查询。如果URI不存在,我必须从Internet上拉取一个图像URL。
所以我设置了截取,从iTunes中提取JSON对象,解析对象,并获取它们的图像URL。
例如,这里是iTunesJSON对象URL,它是包含代表迈克尔杰克逊专辑的各种JSON对象的网页的地址。
String url = "https://itunes.apple.com/search?term=michael+jackson";
现在假设我想为我的所有歌曲使用来自这些JSON专辑对象之一的图像URL。如果我使用Picasso在我的列表和网格上生成图像,那么我需要在Volley的onACK方法中调用Picasso。如果有更好的方法,请告诉我。
这是我的列表适配器之一
SongObject songObject = songObjectList.get(position);
ViewHolder viewHolder;
if (convertView == null) {
viewHolder = new ViewHolder();
LayoutInflater inflater = LayoutInflater.from(getContext());
convertView = inflater.inflate(R.layout.item_list_view, parent, false);
convertView.setTag(viewHolder);
} else {
viewHolder = (ViewHolder) convertView.getTag();
}
viewHolder.albumArt = (ImageView) convertView.findViewById(R.id.album_art);
// Here I check if songObject.albumArtURI is null, and use Picasso
if(songObject.albumArtURI != null){
File f = new File(songObject.albumArtURI);
Picasso.with(viewHolder.albumArt.getContext())
.load(f)
.transform(new CircleTransform())
.placeholder(R.drawable.blackcircle)
.into(viewHolder.albumArt);
} else {
// If songObject.albumArtURI is null, I use Picasso inside Volley's onResponse method
VolleyClass vc = new VolleyClass(getContext());
vc.runVolley();
}
这里是. runVolley()方法
// Here I set up the request queu
RequestQueue requestQueue = Volley.newRequestQueue(ctx);
// Here I make an json object request
JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(url, new Response.Listener<JSONObject>() {
@Override
// Here I use GSON in the onResponse method to parse the object(s)
public void onResponse(JSONObject response) {
if (response != null) {
int resultCount = response.optInt("resultCount");
if (resultCount > 0) {
Gson gson = new Gson();
JSONArray jsonArray = response.optJSONArray("results");
if (jsonArray != null) {
// Here I parse the JSON object(s) into their Java class
SongInfo[] JSONObjectsList = gson.fromJson(jsonArray.toString(), SongInfo[].class);
// Here I use Picasso
Picasso.with(ctx)
.load(String.valueOf(JSONObjectsList[0].artworkUrl30))
.transform(new CircleTransform())
.placeholder(R.drawable.blackcircle)
.into(iv);
}
}
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.e("LOG", error.toString());
}
});
// Here I add the object request object to the queue
requestQueue。add(jsonObjectRequest);代码正在运行,但问题是我在运行时的帧速率非常糟糕,如果我在列表视图中滚动过快,我的应用程序就会崩溃。错误日志在这篇文章的底部。
错误的帧速率似乎不是由毕加索造成的。如果我在onResponse方法中注释掉毕加索代码,我会得到相同的行为。
我认为问题在于,我在列表适配器的每个新迭代中都创建了requestQueue的一个新实例。我尝试过使用单例方法,但没有成功。
如何设置Volley以使用我的列表适配器并处理大量jsonObjectRequest?
11-27 01:25:21.482 32167-32182/ I/art: Background sticky concurrent mark sweep GC freed 157894(7MB) AllocSpace objects, 62(5MB) LOS objects, 9% free, 63MB/69MB, paused 9.954ms total 196.412ms
11-27 01:25:21.502 32167-32167/ D/ViewRootImpl: ViewPostImeInputStage ACTION_DOWN
11-27 01:25:21.602 32167-32182/ W/art: Suspending all threads took: 8.316ms
11-27 01:25:21.662 32167-32182/ I/art: Background partial concurrent mark sweep GC freed 160421(7MB) AllocSpace objects, 36(3MB) LOS objects, 22% free, 55MB/71MB, paused 16.171ms total 156.768ms
11-27 01:25:21.672 32167-32182/ W/art: Suspending all threads took: 5.037ms
11-27 01:25:21.712 32167-32174/ W/art: Suspending all threads took: 36.212ms
11-27 01:25:21.732 32167-32182/ I/art: Background sticky concurrent mark sweep GC freed 6365(305KB) AllocSpace objects, 6(372KB) LOS objects, 12% free, 55MB/63MB, paused 11.009ms total 55.466ms
11-27 01:25:21.772 32167-32167/ D/ViewRootImpl: ViewPostImeInputStage ACTION_DOWN
11-27 01:25:21.862 32167-32167/ D/ViewRootImpl: ViewPostImeInputStage ACTION_DOWN
11-27 01:25:22.062 32167-32167/ D/ViewRootImpl: ViewPostImeInputStage ACTION_DOWN
11-27 01:25:22.102 32167-32182/ I/art: Background partial concurrent mark sweep GC freed 134151(6MB) AllocSpace objects, 47(4MB) LOS objects, 22% free, 55MB/71MB, paused 11.466ms total 128.496ms
11-27 01:25:22.362 32167-32167/ D/ViewRootImpl: ViewPostImeInputStage ACTION_DOWN
11-27 01:25:22.652 32167-32182/ I/art: Background sticky concurrent mark sweep GC freed 171943(7MB) AllocSpace objects, 86(7MB) LOS objects, 11% free, 59MB/67MB, paused 6.646ms total 90.801ms
11-27 01:25:22.662 32167-32167/ D/ViewRootImpl: ViewPostImeInputStage ACTION_DOWN
11-27 01:25:22.712 32167-32174/ W/art: Suspending all threads took: 33.982ms
11-27 01:25:22.742 32167-32182/ I/art: Background partial concurrent mark sweep GC freed 124437(6MB) AllocSpace objects, 24(2MB) LOS objects, 23% free, 52MB/68MB, paused 12.255ms total 87.884ms
11-27 01:25:22.932 32167-32167/ D/ViewRootImpl: ViewPostImeInputStage ACTION_DOWN
11-27 01:25:23.192 32167-32167/ D/ViewRootImpl: ViewPostImeInputStage ACTION_DOWN
11-27 01:25:23.192 32167-32167/ I/Choreographer: Skipped 127 frames! The application may be doing too much work on its main thread.
11-27 01:25:23.342 32167-32182/ I/art: Background sticky concurrent mark sweep GC freed 152008(7MB) AllocSpace objects, 69(6MB) LOS objects, 12% free, 57MB/65MB, paused 11.857ms total 124.020ms
11-27 01:25:23.702 32167-32174/ W/art: Suspending all threads took: 29.615ms
11-27 01:25:23.772 32167-32182/ I/art: Background partial concurrent mark sweep GC freed 165355(7MB) AllocSpace objects, 26(3MB) LOS objects, 21% free, 56MB/72MB, paused 10.798ms total 159.423ms
11-27 01:25:23.852 32167-32182/ I/art: Background sticky concurrent mark sweep GC freed 16824(674KB) AllocSpace objects, 1(150KB) LOS objects, 12% free, 57MB/65MB, paused 7.395ms total 66.835ms
11-27 01:25:24.182 32167-32174/ W/art: Suspending all threads took: 10.983ms
11-27 01:25:24.562 32167-32182/ I/art: Background partial concurrent mark sweep GC freed 60495(2MB) AllocSpace objects, 15(2MB) LOS objects, 20% free, 62MB/78MB, paused 12.542ms total 196.419ms
11-27 01:25:24.632 32167-32182/ I/art: Background sticky concurrent mark sweep GC freed 6414(236KB) AllocSpace objects, 0(0B) LOS objects, 11% free, 63MB/71MB, paused 10.624ms total 67.043ms
11-27 01:25:24.932 32167-32167/ W/libc: pthread_create failed: couldn't allocate 1064960-byte stack: Out of memory
11-27 01:25:24.932 32167-32167/ E/art: Throwing OutOfMemoryError "pthread_create (1040KB stack) failed: Try again"
11-27 01:25:24.932 32167-32167/ D/AndroidRuntime: Shutting down VM
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: FATAL EXCEPTION: main
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: Process: , PID: 32167
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: java.lang.OutOfMemoryError: pthread_create (1040KB stack) failed: Try again
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at java.lang.Thread.nativeCreate(Native Method)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at java.lang.Thread.start(Thread.java:1063)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at com.android.volley.RequestQueue.start(RequestQueue.java:145)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at com.android.volley.toolbox.Volley.newRequestQueue(Volley.java:79)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at com.android.volley.toolbox.Volley.newRequestQueue(Volley.java:105)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at com.android.volley.toolbox.Volley.newRequestQueue(Volley.java:115)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at .ServiceHandler.runVolley(ServiceHandler.java:41)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at .MyListAdapterTracks.getView(MyListAdapterTracks.java:119)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at android.widget.AbsListView.obtainView(AbsListView.java:2825)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at android.widget.ListView.makeAndAddView(ListView.java:1884)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at android.widget.ListView.fillDown(ListView.java:713)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at android.widget.ListView.fillGap(ListView.java:677)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at android.widget.AbsListView.trackMotionScroll(AbsListView.java:7043)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at android.widget.AbsListView$FlingRunnable.run(AbsListView.java:6481)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at android.view.Choreographer$CallbackRecord.run(Choreographer.java:777)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at android.view.Choreographer.doCallbacks(Choreographer.java:590)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at android.view.Choreographer.doFrame(Choreographer.java:559)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:763)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at android.os.Handler.handleCallback(Handler.java:739)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at android.os.Handler.dispatchMessage(Handler.java:95)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at android.os.Looper.loop(Looper.java:145)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at android.app.ActivityThread.main(ActivityThread.java:5944)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at java.lang.reflect.Method.invoke(Native Method)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at java.lang.reflect.Method.invoke(Method.java:372)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
11-27 01:25:24.932 32167-32167/ E/AndroidRuntime: at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)
11-27 01:25:25.062 32167-2055/ A/libc: Fatal signal 11 (SIGSEGV), code 1, fault add
我认为问题在于您总是为每个请求创建RequestQueues。如果是这种情况,请将程序更改为使用RequestQueue的一个公共实例。plz指的是列表适配器中的post-Volley Plus OutOfMemoryError
如何在方法之外声明Request estQueue Request estQueue并进入您首先检查的方法,如果是这种情况,则初始化它,否则只需发出您的请求。
public class VolleyAppController extends Application {
private RequestQueue mRequestQueue;
private static VolleyAppController sInstance;
@Override
public void onCreate() {
super.onCreate();
// initialize the singleton
sInstance = this;
}
public static synchronized VolleyAppController getInstance() {
return sInstance;
}
public RequestQueue getRequestQueue() {
if (mRequestQueue == null) {
mRequestQueue = Volley.newRequestQueue(getApplicationContext());
}
return mRequestQueue;
}
public void addToRequestQueue(Request req) {
getRequestQueue().add(req);
}
}
现在您可以这样使用它:
JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(url, new Response.Listener<JSONObject>() {
@Override
// Here I use GSON in the onResponse method to parse the object(s)
public void onResponse(JSONObject response) {
if (response != null) {
int resultCount = response.optInt("resultCount");
if (resultCount > 0) {
Gson gson = new Gson();
JSONArray jsonArray = response.optJSONArray("results");
if (jsonArray != null) {
// Here I parse the JSON object(s) into their Java class
SongInfo[] JSONObjectsList = gson.fromJson(jsonArray.toString(), SongInfo[].class);
// Here I use Picasso
Picasso.with(ctx)
.load(String.valueOf(JSONObjectsList[0].artworkUrl30))
.transform(new CircleTransform())
.placeholder(R.drawable.blackcircle)
.into(iv);
}
}
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
Log.e("LOG", error.toString());
}
});
VolleyAppController.getInstance().addToRequestQueue(jsonObjectRequest);
希望对你有所帮助。
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