从JSON的Android延迟加载图像输入的GridView [英] Android Lazy loading Images from JSON into gridview
问题描述
,所以我想从我返回的JSON阵列图像加载到一个交错的GridView。我已经测试将链接直接进入像例子中的数组和它的作品完美,但一旦我尝试使用JSON数据,我得到的错误。(网络和存储错误)
我拥有所有必需的permmissions在我的清单(即互联网,内部和外部存储)
下面是我的code,可有人请让我知道什么是错?谢谢!
包com.example.staggeredgridviewdemo;进口org.json.JSONArray;
进口org.json.JSONException;
进口org.json.JSONObject;进口android.app.Activity;
进口android.os.AsyncTask;
进口android.os.Bundle;进口com.origamilabs.library.views.StaggeredGridView;/ **
*
*这是行不通的那么大,因为imageViews的高度是
*在iamgeLoader回调破坏了偏移量计算。为了解决这个问题的尝试
*以获得(本征)图像的宽度和高度,并设置次高度
*手动。我会考虑修复一次,我觉得额外的时间。
*
* @author Maurycy Wojtowicz
*
* /
公共类MainActivity延伸活动{ / *
*图片均是由罗曼专家!他是一个伟大的摄影师,以及一个
*伟大的程序员。 http://www.flickr.com/photos/romainguy
* / 私人字符串的URL [];
字符串位置=http://snapoodle.com/APIS/android/feed.php;
静态最后弦乐TAG_ITEMS =打印; / *
*私人字符串的URL [] = {
*http://farm7.staticflickr.com/6101/6853156632_6374976d38_c.jpg
*http://farm8.staticflickr.com/7084/6885444694_6272874cfc.jpg};
* /
/ **
*这是行不通的那么大,因为imageViews的高度是
*在iamgeLoader回调破坏了偏移量计算。为了解决这个问题
*尝试获得(固有)图像的宽度和高度,并设置意见
*手动高度。我会考虑修复一次,我觉得额外的时间。
* /
@覆盖
保护无效的onCreate(捆绑savedInstanceState){
super.onCreate(savedInstanceState);
的setContentView(R.layout.activity_main);
StaggeredGridView的GridView =(StaggeredGridView)本
.findViewById(R.id.staggeredGridView1);
getImages GET =(getImages)新getImages();
get.execute(位置); // INT保证金= getResources()getDimensionPixelSize(R.dimen.margin)。 //gridView.setItemMargin(margin); //设置GridView的保证金 //gridView.setPadding(margin,0,余量,0); //对保证金
//两侧以及 StaggeredAdapter适配器=新StaggeredAdapter(MainActivity.this,
R.id.imageView1,网址); gridView.setAdapter(适配器);
adapter.notifyDataSetChanged();
} 类getImages扩展的AsyncTask<弦乐,太虚,字符串> { @覆盖
保护字符串doInBackground(字符串... PARAMS){
// TODO自动生成方法存根
JSONObject的JSON = JSONfunctions
.getJSONfromURL(位置); 尝试{
JSONArray jarray;
jarray = json.getJSONArray(TAG_ITEMS);
网址=新的String [jarray.length()]; 的for(int i = 0; I< jarray.length();我++){
JSONObject的gridImages = jarray.getJSONObject(I)
网址[I] = gridImages.getString(saved_location);
} }赶上(JSONException E){
// TODO自动生成catch块
e.printStackTrace();
}
返回null;
} }}
logcat的
14 03-22:57:59.276:D / AndroidRuntime(1183):关闭VM
03-22 14:57:59.276:W / dalvikvm(1183):主题ID = 1:螺纹未捕获的异常退出(组= 0x4111f930)
03-22 14:57:59.286:E / AndroidRuntime(1183):致命异常:主要
03-22 14:57:59.286:E / AndroidRuntime(1183):了java.lang.RuntimeException:无法启动活动ComponentInfo {com.example.staggeredgridviewdemo / com.example.staggeredgridviewdemo.MainActivity}:显示java.lang.NullPointerException:存储== NULL
03-22 14:57:59.286:E / AndroidRuntime(1183):在android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
03-22 14:57:59.286:E / AndroidRuntime(1183):在android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
03-22 14:57:59.286:E / AndroidRuntime(1183):在android.app.ActivityThread.access $ 600(ActivityThread.java:141)
03-22 14:57:59.286:E / AndroidRuntime(1183):在android.app.ActivityThread $ H.handleMessage(ActivityThread.java:1234)
03-22 14:57:59.286:E / AndroidRuntime(1183):在android.os.Handler.dispatchMessage(Handler.java:99)
03-22 14:57:59.286:E / AndroidRuntime(1183):在android.os.Looper.loop(Looper.java:137)
03-22 14:57:59.286:E / AndroidRuntime(1183):在android.app.ActivityThread.main(ActivityThread.java:5041)
03-22 14:57:59.286:E / AndroidRuntime(1183):在java.lang.reflect.Method.invokeNative(本机方法)
03-22 14:57:59.286:E / AndroidRuntime(1183):在java.lang.reflect.Method.invoke(Method.java:511)
03-22 14:57:59.286:E / AndroidRuntime(1183):在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:793)
03-22 14:57:59.286:E / AndroidRuntime(1183):在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
03-22 14:57:59.286:E / AndroidRuntime(1183):在dalvik.system.NativeStart.main(本机方法)
03-22 14:57:59.286:E / AndroidRuntime(1183):显示java.lang.NullPointerException:由导致的存储== NULL
03-22 14:57:59.286:E / AndroidRuntime(1183):在java.util.Arrays中的$的ArrayList<&初始化GT;(Arrays.java:38)
03-22 14:57:59.286:E / AndroidRuntime(1183):在java.util.Arrays.asList(Arrays.java:154)
03-22 14:57:59.286:E / AndroidRuntime(1183):在android.widget.ArrayAdapter<&初始化GT;(ArrayAdapter.java:128)
03-22 14:57:59.286:E / AndroidRuntime(1183):在com.example.staggeredgridviewdemo.StaggeredAdapter<&初始化GT;(StaggeredAdapter.java:20)
03-22 14:57:59.286:E / AndroidRuntime(1183):在com.example.staggeredgridviewdemo.MainActivity.onCreate(MainActivity.java:89)
03-22 14:57:59.286:E / AndroidRuntime(1183):在android.app.Activity.performCreate(Activity.java:5104)
03-22 14:57:59.286:E / AndroidRuntime(1183):在android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
03-22 14:57:59.286:E / AndroidRuntime(1183):在android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
03-22 14:57:59.286:E / AndroidRuntime(1183):11 ...更多
03-22 14:57:59.316:D / dalvikvm(1183):GC_CONCURRENT释放176K,3%的自由8878K / 9084K,暂停3毫秒+ 1毫秒,总19ms
我是有点愚蠢,但我通过移动我的交错网格视图onPostExecute和返回网址,做后台解决它
So i am trying to load images from my returned json array into a staggered gridview. I have already tested putting links directly into the array like the example and it works perfectly, but once i try to use json data, i get errors.(Both network, and storage errors) I have all the required permmissions in my manifest(ie, internet, internal and external storage)
Here is my code, can somebody please let me know what's wrong? Thanks!!
package com.example.staggeredgridviewdemo;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import android.app.Activity;
import android.os.AsyncTask;
import android.os.Bundle;
import com.origamilabs.library.views.StaggeredGridView;
/**
*
* This will not work so great since the heights of the imageViews are
* calculated on the iamgeLoader callback ruining the offsets. To fix this try
* to get the (intrinsic) image width and height and set the views height
* manually. I will look into a fix once I find extra time.
*
* @author Maurycy Wojtowicz
*
*/
public class MainActivity extends Activity {
/*
* Images are taken by Romain Guy ! He's a great photographer as well as a
* great programmer. http://www.flickr.com/photos/romainguy
*/
private String urls[];
String location = "http://snapoodle.com/APIS/android/feed.php";
static final String TAG_ITEMS = "print";
/*
* private String urls[] = {
* "http://farm7.staticflickr.com/6101/6853156632_6374976d38_c.jpg",
* "http://farm8.staticflickr.com/7084/6885444694_6272874cfc.jpg" };
*/
/**
* This will not work so great since the heights of the imageViews are
* calculated on the iamgeLoader callback ruining the offsets. To fix this
* try to get the (intrinsic) image width and height and set the views
* height manually. I will look into a fix once I find extra time.
*/
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
StaggeredGridView gridView = (StaggeredGridView) this
.findViewById(R.id.staggeredGridView1);
getImages get= (getImages) new getImages();
get.execute(location);
//int margin = getResources().getDimensionPixelSize(R.dimen.margin);
//gridView.setItemMargin(margin); // set the GridView margin
//gridView.setPadding(margin, 0, margin, 0); // have the margin on the
// sides as well
StaggeredAdapter adapter = new StaggeredAdapter(MainActivity.this,
R.id.imageView1, urls);
gridView.setAdapter(adapter);
adapter.notifyDataSetChanged();
}
class getImages extends AsyncTask<String, Void, String> {
@Override
protected String doInBackground(String... params) {
// TODO Auto-generated method stub
JSONObject json = JSONfunctions
.getJSONfromURL(location);
try {
JSONArray jarray;
jarray = json.getJSONArray(TAG_ITEMS);
urls = new String[jarray.length()];
for (int i = 0; i < jarray.length(); i++) {
JSONObject gridImages = jarray.getJSONObject(i);
urls[i] = gridImages.getString("saved_location");
}
} catch (JSONException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
}
}
logcat
03-22 14:57:59.276: D/AndroidRuntime(1183): Shutting down VM
03-22 14:57:59.276: W/dalvikvm(1183): threadid=1: thread exiting with uncaught exception (group=0x4111f930)
03-22 14:57:59.286: E/AndroidRuntime(1183): FATAL EXCEPTION: main
03-22 14:57:59.286: E/AndroidRuntime(1183): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.staggeredgridviewdemo/com.example.staggeredgridviewdemo.MainActivity}: java.lang.NullPointerException: storage == null
03-22 14:57:59.286: E/AndroidRuntime(1183): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
03-22 14:57:59.286: E/AndroidRuntime(1183): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
03-22 14:57:59.286: E/AndroidRuntime(1183): at android.app.ActivityThread.access$600(ActivityThread.java:141)
03-22 14:57:59.286: E/AndroidRuntime(1183): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
03-22 14:57:59.286: E/AndroidRuntime(1183): at android.os.Handler.dispatchMessage(Handler.java:99)
03-22 14:57:59.286: E/AndroidRuntime(1183): at android.os.Looper.loop(Looper.java:137)
03-22 14:57:59.286: E/AndroidRuntime(1183): at android.app.ActivityThread.main(ActivityThread.java:5041)
03-22 14:57:59.286: E/AndroidRuntime(1183): at java.lang.reflect.Method.invokeNative(Native Method)
03-22 14:57:59.286: E/AndroidRuntime(1183): at java.lang.reflect.Method.invoke(Method.java:511)
03-22 14:57:59.286: E/AndroidRuntime(1183): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
03-22 14:57:59.286: E/AndroidRuntime(1183): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
03-22 14:57:59.286: E/AndroidRuntime(1183): at dalvik.system.NativeStart.main(Native Method)
03-22 14:57:59.286: E/AndroidRuntime(1183): Caused by: java.lang.NullPointerException: storage == null
03-22 14:57:59.286: E/AndroidRuntime(1183): at java.util.Arrays$ArrayList.<init>(Arrays.java:38)
03-22 14:57:59.286: E/AndroidRuntime(1183): at java.util.Arrays.asList(Arrays.java:154)
03-22 14:57:59.286: E/AndroidRuntime(1183): at android.widget.ArrayAdapter.<init>(ArrayAdapter.java:128)
03-22 14:57:59.286: E/AndroidRuntime(1183): at com.example.staggeredgridviewdemo.StaggeredAdapter.<init>(StaggeredAdapter.java:20)
03-22 14:57:59.286: E/AndroidRuntime(1183): at com.example.staggeredgridviewdemo.MainActivity.onCreate(MainActivity.java:89)
03-22 14:57:59.286: E/AndroidRuntime(1183): at android.app.Activity.performCreate(Activity.java:5104)
03-22 14:57:59.286: E/AndroidRuntime(1183): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
03-22 14:57:59.286: E/AndroidRuntime(1183): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
03-22 14:57:59.286: E/AndroidRuntime(1183): ... 11 more
03-22 14:57:59.316: D/dalvikvm(1183): GC_CONCURRENT freed 176K, 3% free 8878K/9084K, paused 3ms+1ms, total 19ms
I was a bit dumb, but I solved it by moving my staggered grid view to onPostExecute and returning urls from do in background
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