0 
07-30 09:20:22.401: E/AndroidRuntime(1748): FATAL EXCEPTION: main
07-30 09:20:22.401: E/AndroidRuntime(1748): java.lang.NullPointerException
07-30 09:20:22.401: E/AndroidRuntime(1748):     at com.example.swiperefreshdemoprac.adapter.DemoAdapter.getView(DemoAdapter.java:78)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.widget.AbsListView.obtainView(AbsListView.java:2143)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.widget.ListView.makeAndAddView(ListView.java:1831)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.widget.ListView.fillSpecific(ListView.java:1320)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.widget.ListView.layoutChildren(ListView.java:1630)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.widget.AbsListView.onLayout(AbsListView.java:1994)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.View.layout(View.java:14008)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.ViewGroup.layout(ViewGroup.java:4373)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.support.v4.widget.SwipeRefreshLayout.onLayout(SwipeRefreshLayout.java:324)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.View.layout(View.java:14008)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.ViewGroup.layout(ViewGroup.java:4373)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.widget.FrameLayout.onLayout(FrameLayout.java:448)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.View.layout(View.java:14008)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.ViewGroup.layout(ViewGroup.java:4373)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1663)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.widget.LinearLayout.layoutVertical(LinearLayout.java:1521)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.widget.LinearLayout.onLayout(LinearLayout.java:1434)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.View.layout(View.java:14008)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.ViewGroup.layout(ViewGroup.java:4373)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.widget.FrameLayout.onLayout(FrameLayout.java:448)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.View.layout(View.java:14008)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.ViewGroup.layout(ViewGroup.java:4373)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.ViewRootImpl.performLayout(ViewRootImpl.java:1892)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1711)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:989)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:4351)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.Choreographer$CallbackRecord.run(Choreographer.java:749)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.Choreographer.doCallbacks(Choreographer.java:562)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.Choreographer.doFrame(Choreographer.java:532)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:735)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.os.Handler.handleCallback(Handler.java:725)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.os.Handler.dispatchMessage(Handler.java:92)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.os.Looper.loop(Looper.java:137)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at android.app.ActivityThread.main(ActivityThread.java:5041)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at java.lang.reflect.Method.invokeNative(Native Method)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at java.lang.reflect.Method.invoke(Method.java:511)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
07-30 09:20:22.401: E/AndroidRuntime(1748):     at dalvik.system.NativeStart.main(Native Method)
07-30 09:22:37.049: E/Trace(1806): error opening trace file: No such file or directory (2)

我正在做的事情是在 BaseAdapter 的帮助下在 SwipeRefreshLayout 中加载一些数据。完整代码如下。

这是主要的活动课。

MainActivity.java

    package com.example.swiperefreshdemoprac.activity;

    import java.util.ArrayList;
    import java.util.List;

    import android.app.Activity;
    import android.graphics.Bitmap;
    import android.graphics.BitmapFactory;
    import android.os.Bundle;
    import android.os.SystemClock;
    import android.support.v4.widget.SwipeRefreshLayout;
    import android.support.v4.widget.SwipeRefreshLayout.OnRefreshListener;
    import android.util.Log;
    import android.view.Menu;
    import android.view.View;
    import android.widget.AdapterView;
    import android.widget.Toast;
    import android.widget.AdapterView.OnItemClickListener;
    import android.widget.ListView;

    import com.example.swiperefreshdemoprac.R;
    import com.example.swiperefreshdemoprac.adapter.DemoAdapter;
    import com.example.swiperefreshdemoprac.gettersetter.GetterSetter;
    import com.parse.FindCallback;
    import com.parse.ParseException;
    import com.parse.ParseFile;
    import com.parse.ParseObject;
    import com.parse.ParseQuery;

    public class MainActivity extends Activity implements OnItemClickListener,OnRefreshListener{
        private SwipeRefreshLayout swipeRefreshLayout;
        Bitmap VideoThumbImage = null;
        ListView VideolistView;
        DemoAdapter adapter;
        ArrayList<GetterSetter> newArray = new ArrayList<GetterSetter>();
        ArrayList<GetterSetter> newArray2 = new ArrayList<GetterSetter>();
        public List<ParseObject> objectTest;
        int initialnum = 0;
        int finalnum = 5;


        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
         //   setContentView(R.layout.activity_main);
            swipeRefreshLayout = new SwipeRefreshLayout(MainActivity.this);
            setContentView(swipeRefreshLayout);
            VideolistView = new ListView(MainActivity.this);
            ParseQuery<ParseObject> newQuery = ParseQuery.getQuery("Videos");
            newQuery.whereExists("url");
            newQuery.addDescendingOrder("number");
            newQuery.findInBackground(new FindCallback<ParseObject>() {

                @Override
                public void done(List<ParseObject> list, ParseException e) {
                    // TODO Auto-generated method stub
                    if (e == null) {
                        int dataSize = list.size();
                        for (int i = initialnum; i < finalnum; i++) {
                            ParseFile Youtubeimage = (ParseFile) list.get(i).get(
                                    "VideoImage");
                            byte[] imageconvert;
                            try {
                                imageconvert = Youtubeimage.getData();
                                VideoThumbImage = BitmapFactory.decodeByteArray(
                                        imageconvert, 0, imageconvert.length);

                            } catch (ParseException ee) {
                                ee.printStackTrace();
                            }
                            String Title = (String) list.get(i).get("Title");
                            String urlYou = (String) list.get(i).get("url");
                            GetterSetter setItNow = new GetterSetter();
                            setItNow.setImage(VideoThumbImage);
                            setItNow.setTitle(Title);
                            setItNow.setUrl(urlYou);
                            newArray.add(setItNow);
                        }
                        adapter = new DemoAdapter(getApplicationContext(),
                                newArray);
                        VideolistView.setAdapter(adapter);
                        VideolistView.setOnItemClickListener(MainActivity.this);

                        objectTest = list;
                        initialnum = finalnum;
                        if((list.size()-finalnum)>5){
                            finalnum = finalnum+5;
                        } else {
                            finalnum = list.size() - finalnum;
                        }

                    } else {
                        e.printStackTrace();
                    }
                }
            });
            Log.d("THis is ", "7");
            Log.d("This is Testing", "Testing");
    //      Log.d("The size is", "This is the size :- "+objectTest.size());

            swipeRefreshLayout.addView(VideolistView);
            swipeRefreshLayout.setOnRefreshListener(this);

        }

        @Override
        public void onRefresh() {
            // TODO Auto-generated method stub

            new Thread(){
                public void run() {
                    SystemClock.sleep(2000);

                    MainActivity.this.runOnUiThread(new Runnable() {

                        @Override
                        public void run() {
                            // TODO Auto-generated method stub
                            Toast.makeText(MainActivity.this,"This is the object Length :- "+objectTest.size() +", This is the ini :- "+initialnum+", This si the final num" + finalnum, Toast.LENGTH_SHORT).show();
                            for (int i = initialnum; i < finalnum; i++) {
                                ParseFile Youtubeimage = (ParseFile) objectTest.get(i).get(
                                        "VideoImage");
                                byte[] imageconvert;
                                try {
                                    imageconvert = Youtubeimage.getData();
                                    VideoThumbImage = BitmapFactory.decodeByteArray(
                                            imageconvert, 0, imageconvert.length);

                                } catch (ParseException ee) {
                                    ee.printStackTrace();
                                }
                                String Title = (String) objectTest.get(i).get("Title");
                                String urlYou = (String) objectTest.get(i).get("url");
                                GetterSetter setItNow2 = new GetterSetter();
                                setItNow2.setImage(VideoThumbImage);
                                setItNow2.setTitle(Title);
                                setItNow2.setUrl(urlYou);
                                newArray2.add(setItNow2);
                            }
                            Toast.makeText(MainActivity.this, "This is the size of the new Array :- " + newArray.size(), Toast.LENGTH_SHORT).show();
                            adapter.DemoAdapter2(MainActivity.this, newArray2);
                    //      adapter.notifyDataSetChanged();
                    //      adapter.notifyDataSetChanged();
                            swipeRefreshLayout.setRefreshing(false);
    //                      VideolistView.setAdapter(adapter);

                        }
                    });
                };
            }.start();

        }

        @Override
        public boolean onCreateOptionsMenu(Menu menu) {
            // Inflate the menu; this adds items to the action bar if it is present.
            getMenuInflater().inflate(R.menu.main, menu);
            return true;
        }

        @Override
        public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
            // TODO Auto-generated method stub

        }

    }

这是适配器类

DemoAdapter.java

    package com.example.swiperefreshdemoprac.adapter;

    import java.util.ArrayList;

    import android.app.Activity;
    import android.content.Context;
    import android.os.Binder;
    import android.util.Log;
    import android.view.LayoutInflater;
    import android.view.View;
    import android.view.ViewGroup;
    import android.widget.BaseAdapter;
    import android.widget.ImageView;
    import android.widget.TextView;
    import android.widget.Toast;

    import com.example.swiperefreshdemoprac.R;
    import com.example.swiperefreshdemoprac.gettersetter.GetterSetter;
    import com.parse.RefreshCallback;

    public class DemoAdapter extends BaseAdapter{

        Context cont;

        ArrayList<GetterSetter> refrehsetter;
        ArrayList<GetterSetter> refrehsetter2;
        LayoutInflater inflate;

        public DemoAdapter(Context cont,ArrayList<GetterSetter> refrehsetter){
            this.cont = cont;
            this.refrehsetter = refrehsetter;
        }

        public void DemoAdapter2(Context cont,ArrayList<GetterSetter> newrefrehsetter) {
            // TODO Auto-generated constructor stub
            this.cont = cont;
            refrehsetter2 = newrefrehsetter;
            this.refrehsetter.addAll(refrehsetter2);
            notifyDataSetChanged();
            Toast.makeText(cont, "This is the size after call :- "+refrehsetter2.size(), Toast.LENGTH_SHORT).show();
    //      refrehsetter.addAll(refrehsetter2);
    //      notifyDataSetChanged();
        }

        public class Holder{
            ImageView image;
            TextView url, Title;

        }

        @Override
        public View getView(int position, View ConvertView, ViewGroup parent) {
            // TODO Auto-generated method stub
            Holder hold = null;
            inflate = (LayoutInflater) cont.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
            if(ConvertView == null){
                ConvertView = inflate.inflate(R.layout.layout_trailer_item, null);
                hold = new Holder();
                hold.image = (ImageView) ConvertView.findViewById(R.id.imageView1);
                hold.Title = (TextView) ConvertView.findViewById(R.id.textView1);
                hold.url = (TextView) ConvertView.findViewById(R.id.urlID);
                Toast.makeText(cont,"This is not the result", Toast.LENGTH_SHORT).show();
            } else {
                hold = (Holder) ConvertView.getTag();
                Toast.makeText(cont,"<<<<<This is the result>>>>>", Toast.LENGTH_SHORT).show();
            }

            GetterSetter getset = (GetterSetter) getItem(position);
            hold.image.setImageBitmap(getset.getImage());
            hold.Title.setText(getset.getTitle());
            hold.url.setText(getset.getUrl());
            return ConvertView; 
        }

        @Override
        public int getCount() {
            // TODO Auto-generated method stub
            return refrehsetter.size();
        }

        @Override
        public Object getItem(int arg0) {
            // TODO Auto-generated method stub
            return refrehsetter.get(arg0);
        }

        @Override
        public long getItemId(int arg0) {
            // TODO Auto-generated method stub
            return refrehsetter.indexOf(getItem(arg0));
        }
    }

下面是 Getter Setter。

GetterSetter.java

    package com.example.swiperefreshdemoprac.gettersetter;

    import android.graphics.Bitmap;

    public class GetterSetter {
    String url;
    Bitmap image;
    String title;
    public String getUrl() {
        return url;
    }
    public void setUrl(String url) {
        this.url = url;
    }
    public Bitmap getImage() {
        return image;
    }
    public void setImage(Bitmap image) {
        this.image = image;
    }
    public String getTitle() {
        return title;
    }
    public void setTitle(String title) {
        this.title = title;
    }

    }

Here I am trying to load the data on refresh but when I swipe to refresh It is not loading the new data that I have got. Can anyone please tell me where am I going wrong.
4

2 回答 2

2

嘿，处理适配器标签时出现错误。我不想设置标签，也没有将布局充气机设置在正确的位置。让我发布适配器类。

package com.example.swiperefreshdemoprac.adapter;

import java.util.ArrayList;

import android.app.Activity;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;

import com.example.swiperefreshdemoprac.R;
import com.example.swiperefreshdemoprac.gettersetter.GetterSetter;

public class DemoAdapter extends BaseAdapter{

    Context cont;

    ArrayList<GetterSetter> refrehsetter;
    LayoutInflater inflate;

    public DemoAdapter(Context cont,ArrayList<GetterSetter> refrehsetter){
        this.cont = cont;
        this.refrehsetter = refrehsetter;
        inflate = (LayoutInflater) cont.getSystemService(Activity.LAYOUT_INFLATER_SERVICE);
    }

    public void updateNewArray(ArrayList<GetterSetter> setit){
    //  refrehsetter.clear();
        refrehsetter.addAll(setit);
        notifyDataSetChanged();
    }

    public class Holder{
        ImageView image;
        TextView url, Title;

    }

    @Override
    public View getView(int position, View ConvertView, ViewGroup parent) {
        // TODO Auto-generated method stub
        Holder hold;
        View view = ConvertView;
        if(ConvertView == null){
            view = inflate.inflate(R.layout.layout_trailer_item, null);
            hold = new Holder();
            hold.image = (ImageView) view.findViewById(R.id.imageView1);
            hold.Title = (TextView) view.findViewById(R.id.textView1);
            hold.url = (TextView) view.findViewById(R.id.urlID);

            view.setTag(hold);

            Toast.makeText(cont,"This is not the result", Toast.LENGTH_SHORT).show();
        } else {
            hold = (Holder) ConvertView.getTag();
            Toast.makeText(cont,"<<<<<This is the result>>>>>", Toast.LENGTH_SHORT).show();
        }

        GetterSetter getset = (GetterSetter) getItem(position);
        hold.image.setImageBitmap(getset.getImage());
        hold.Title.setText(getset.getTitle());
        hold.url.setText(getset.getUrl());
        return view;    
    }

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return refrehsetter.size();
    }

    @Override
    public Object getItem(int arg0) {
        // TODO Auto-generated method stub
        return refrehsetter.get(arg0);
    }

    @Override
    public long getItemId(int arg0) {
        // TODO Auto-generated method stub
        return refrehsetter.indexOf(getItem(arg0));
    }

}
于 2014-08-06T05:27:00.407 回答
0

你得到更多数据了吗？或者您正在获取更新的数据？

如果您正在“刷新”您的列表，那么您不应该将新列表添加到旧列表中，您应该将适配器中的数据源设置为新的刷新列表。

如果您获得更多数据，addAll()该方法将导致在列表底部添加新数据。

于 2014-07-30T09:59:23.380 回答