Question

我正在尝试从Url和文本数据中获取图像，但它已经关闭了App Forcefully。它有什么问题..

public class BandMembers extends ListActivity {
public static final String TAG_MEMBER_NAME = "member_name";
public static final String TAG_MEMBER_SKILL = "member_skill";
public static final String TAG_THUMB_MEMBER_IMAGE = "member_thumb_image";
public static String URL = "http://...../.../..../mainAPI.php"; 

ArrayList<HashMap<String, String>> memberList;
String responseData = null;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.band_members);

    memberList = new ArrayList<HashMap<String,String>>();
    new AsyncData().execute();
}

class AsyncData extends AsyncTask<String, Void, Void> {
    ProgressDialog pDialog;

    @Override
    protected void onPreExecute() {
        pDialog = new ProgressDialog(BandMembers.this);
        pDialog.setTitle("Loading....");
        pDialog.setMessage("Please wait...");
        pDialog.show();
        super.onPreExecute();
    }

    @Override
    protected Void doInBackground(String... args) {
        // TODO Auto-generated method stub
        HttpClient httpclient = new DefaultHttpClient();
        HttpPost httppost = new HttpPost(URL);
        try {
            List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
            nameValuePairs.add(new BasicNameValuePair("rquest","{\"method\":\"band_members\",\"body\":[{}]}"));
            httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs, HTTP.UTF_8));
            HttpResponse response = httpclient.execute(httppost);
            HttpEntity resEntity = response.getEntity();
            responseData = EntityUtils.toString(resEntity);
            try {
                JSONArray data = new JSONArray(responseData);
                for (int i = 0; i < data.length(); i++) {
                    HashMap<String, String> map = new HashMap<String, String>();
                    JSONObject c = data.getJSONObject(i);
                    String memberName = c.getString(TAG_MEMBER_NAME);
                    String memberSkill = c.getString(TAG_MEMBER_SKILL);
                    String memberImage = c.getString(TAG_THUMB_MEMBER_IMAGE);
                    map.put(TAG_MEMBER_NAME, memberName);
                    map.put(TAG_MEMBER_SKILL, memberSkill);
                    map.put(TAG_THUMB_MEMBER_IMAGE, memberImage);
                    memberList.add(map);
                }

            } catch (JSONException e) {
                // TODO: handle exception
                e.printStackTrace();
            }
        } catch (ClientProtocolException e) {
            Toast.makeText(BandMembers.this, "There was an issue Try again later", Toast.LENGTH_LONG).show();
        } catch (IOException e) {
            Toast.makeText(BandMembers.this, "There was an IO issue Try again later", Toast.LENGTH_LONG).show();
        }
        return null;
    }


    protected void onPostExecute(Void result) {
        super.onPostExecute(result);
        if (pDialog != null && pDialog.isShowing()) {
            pDialog.dismiss();
        }


        setListAdapter(new BandAdapter(BandMembers.this,R.layout.band_member_row_file, memberList));

    }
}
}

类带适配器

public class BandAdapter extends ArrayAdapter<HashMap<String, String>>{
Context context;
ArrayList<HashMap<String, String>> myList;
HashMap<String, String> myData;
int layout;
public BandAdapter(Context context, int textViewResourceId, List<HashMap<String, String>> objects) {
    super(context, textViewResourceId, objects);
    // TODO Auto-generated constructor stub
    this.context = context;
    this.myList = (ArrayList<HashMap<String, String>>) objects;
    this.layout = textViewResourceId;
}


@Override
public View getView(int position, View convertView, ViewGroup parent) {
    // TODO Auto-generated method stub
    View row = null;
    TextView name, info;
    ImageView image;
    LayoutInflater inflater = ((Activity) context).getLayoutInflater();
    row = inflater.inflate(layout, parent, false);
    name = (TextView)row.findViewById(R.id.textMemberName);
    info = (TextView)row.findViewById(R.id.textMemberInfo);
    myData = myList.get(position);
    try{
        image = (ImageView)row.findViewById(R.id.imageMember);
        name.setText("" + myData.get(BandMembers.TAG_MEMBER_NAME));
        info.setText("" + myData.get(BandMembers.TAG_MEMBER_SKILL));
        Bitmap bitmap = BitmapFactory.decodeStream((InputStream)new URL ("" + myData.get(BandMembers.TAG_THUMB_MEMBER_IMAGE)).getContent());
        image.setImageBitmap(bitmap);
    } catch (MalformedURLException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
    return row;
}
 }

和我的Logcat是..

04-26 12:01:15.574: E/AndroidRuntime(2575): FATAL EXCEPTION: main
04-26 12:01:15.574: E/AndroidRuntime(2575): android.os.NetworkOnMainThreadException
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1084)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at java.net.InetAddress.lookupHostByName(InetAddress.java:391)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at java.net.InetAddress.getAllByNameImpl(InetAddress.java:242)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at java.net.InetAddress.getAllByName(InetAddress.java:220)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at libcore.net.http.HttpConnection.<init>(HttpConnection.java:71)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at libcore.net.http.HttpConnection.<init>(HttpConnection.java:50)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at libcore.net.http.HttpConnection$Address.connect(HttpConnection.java:351)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at libcore.net.http.HttpConnectionPool.get(HttpConnectionPool.java:86)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at libcore.net.http.HttpConnection.connect(HttpConnection.java:128)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at libcore.net.http.HttpEngine.openSocketConnection(HttpEngine.java:308)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at libcore.net.http.HttpEngine.connect(HttpEngine.java:303)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at libcore.net.http.HttpEngine.sendSocketRequest(HttpEngine.java:282)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at libcore.net.http.HttpEngine.sendRequest(HttpEngine.java:232)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at libcore.net.http.HttpURLConnectionImpl.connect(HttpURLConnectionImpl.java:80)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at java.net.URLConnection.getContent(URLConnection.java:194)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at java.net.URL.getContent(URL.java:447)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at com.bandapp.BandAdapter.getView(BandAdapter.java:51)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.AbsListView.obtainView(AbsListView.java:2033)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.ListView.measureHeightOfChildren(ListView.java:1244)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.ListView.onMeasure(ListView.java:1155)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.View.measure(View.java:12603)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.RelativeLayout.measureChild(RelativeLayout.java:579)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:392)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.View.measure(View.java:12603)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4677)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.View.measure(View.java:12603)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4677)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1369)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.LinearLayout.measureVertical(LinearLayout.java:660)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.LinearLayout.onMeasure(LinearLayout.java:553)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.View.measure(View.java:12603)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4677)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2072)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.View.measure(View.java:12603)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4677)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.View.measure(View.java:12603)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:594)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:376)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.View.measure(View.java:12603)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4677)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.View.measure(View.java:12603)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4677)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.View.measure(View.java:12603)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4677)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1369)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.LinearLayout.measureVertical(LinearLayout.java:660)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.LinearLayout.onMeasure(LinearLayout.java:553)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.View.measure(View.java:12603)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4677)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2072)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.View.measure(View.java:12603)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1044)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.view.ViewRootImpl.handleMessage(ViewRootImpl.java:2418)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.os.Handler.dispatchMessage(Handler.java:99)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.os.Looper.loop(Looper.java:137)
04-26 12:01:15.574: E/AndroidRuntime(2575):     at android.app.ActivityThread.main(ActivityT

请帮助我并提供一些代码解决方案，谢谢你提前..

Answer 1

只需用这个改变BandAdapter类..

public class BandAdapter extends ArrayAdapter<HashMap<String, String>> {
Context context;
ArrayList<HashMap<String, String>> myList;
HashMap<String, String> myData;
int layout;

public BandAdapter(Context context, int textViewResourceId, List<HashMap<String, String>> objects) {
    super(context, textViewResourceId, objects);
    // TODO Auto-generated constructor stub
    this.context = context;
    this.myList = (ArrayList<HashMap<String, String>>) objects;
    this.layout = textViewResourceId;
}


@Override
public View getView(int position, View convertView, ViewGroup parent) {
    // TODO Auto-generated method stub
    View row = null;
    TextView name, info;
    ImageView image;
    Bitmap bimage;

    LayoutInflater inflater = ((Activity) context).getLayoutInflater();
    row = inflater.inflate(layout, parent, false);
    name = (TextView)row.findViewById(R.id.textMemberName);
    info = (TextView)row.findViewById(R.id.textMemberInfo);
    myData = myList.get(position);
    try{
        image = (ImageView)row.findViewById(R.id.imageMember);
        name.setText("" + myData.get(BandMembers.TAG_MEMBER_NAME));
        info.setText("" + myData.get(BandMembers.TAG_MEMBER_SKILL));
        String uri = ("" + myData.get(BandMembers.TAG_THUMB_MEMBER_IMAGE).replace(" ", "%20"));
        bimage=  getBitmapFromURL(uri);
        image.setImageBitmap(bimage);
    } catch (Exception e) {
        e.printStackTrace();
    }
    return row;
}
public static Bitmap getBitmapFromURL(String src) {
    try {
        URL url = new URL(src);
        HttpURLConnection connection = (HttpURLConnection) url.openConnection();
        connection.setDoInput(true);
        connection.connect();
        InputStream input = connection.getInputStream();
        Bitmap myBitmap = BitmapFactory.decodeStream(input);
        return myBitmap;
    } catch (IOException e) {
        e.printStackTrace();
        return null;
    }
  }
}

Answer 2

如果您要下载并在imageview中显示图像，请尝试智能图像视图

http://loopj.com/android-smart-image-view/

它的工作非常好。

Answer 3

你可以使用Android查询库来延迟加载你的图像，它非常简单明了，你只需要指定图像的url，这个库就可以为你完成所有的缓存和图像下载你的异常是主线程异常上的网络，你不应该在doInBackground方法中进行任何ui相关的更改例如，加载图像的代码只有一行

//fetch and set the image from internet, cache with file and memory 
aq.id(R.id.image1).image("http://www.vikispot.com/z/images/vikispot/android-w.png");

您可以在（https://code.google.com/p/android-query/）

查看公寓

Answer 4

        Toast.makeText(BandMembers.this, "There was an issue Try again later", Toast.LENGTH_LONG).show();

在frist Toast中不能在doInBackground中使用。这是工作线程。您应该始终在UI线程中处理您的UI。

同时，

Bitmap bitmap = BitmapFactory.decodeStream((InputStream)new URL ("" +    myData.get(BandMembers.TAG_THUMB_MEMBER_IMAGE)).getContent());

似乎是从网络获取图像。它应该始终在工作线程中运行。除非你得到android.os.NetworkOnMainThreadException。这就是你得到例外的原因。

您可以创建Asyntask来加载图像：

 class ImageDownloadTask extends AsyncTask<Void, Integer, Bitmap> {
        private ImageView mView;
        ImageDownloadTask(ImageView view){
            mView = view;
        }
        @Override
        protected Bitmap doInBackground(Void... params) {
              Bitmap bitmap = BitmapFactory.decodeStream((InputStream)new URL(""
                  + myData.get(BandMembers.TAG_THUMB_MEMBER_IMAGE)).getContent());
              return bitmap;
        }


        @Override
        protected void onPostExecute(Bitmap result) {
           mView.setImageBitmap(result);
        }
}

然后新建一个SynckTask，在getView方法

中加载图片

 try{
        image = (ImageView)row.findViewById(R.id.imageMember);
        name.setText("" + myData.get(BandMembers.TAG_MEMBER_NAME));
        info.setText("" + myData.get(BandMembers.TAG_MEMBER_SKILL));
        ImageDownloadTask task = new ImageDownloadTask(image);
        task.execute();
    }

在Android中从URL加载图像

4 个答案: