Question

我试过可能是这里的每一个解决方案，但没有任何帮助我。图像不会在列表视图中仅显示文本。我只在LogCat

中得到了这个

11-04 14:46:29.319: I/(1225): {"Restaurants":[{"id":"1","name":"Restaurant- 1","menu":"Restaurant-1","image":"rest1.jpg"},{"id":"2","name":"Restaurant-2","menu":"Restaurant-2","image":"rest2.jpg"},{"id":"3","name":"Restaurant-3","menu":"Restaurant-3","image":"rest3.jpg"},{"id":"4","name":"Restaurant-4","menu":"Restaurant-4","image":"rest4.jpg"}]} 
11-04 14:46:29.329: E/err(1225): rest1.jpg Restaurant-1 Restaurant-1
11-04 14:46:29.329: E/err(1225): rest2.jpg Restaurant-2 Restaurant-2
11-04 14:46:29.329: E/err(1225): rest3.jpg Restaurant-3 Restaurant-3
11-04 14:46:29.329: E/err(1225): rest4.jpg Restaurant-4 Restaurant-4

这是代码

public class Restaurants extends Activity {

ListView listView;
private StockAdaptor stockAdaptor;
String jsonResult = null;
ImageView image;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.restaurants);
    listView = (ListView) findViewById(android.R.id.list);
    image = (ImageView) findViewById(R.id.image);
    new JsonReadTask().execute("http://link/GetRestaurants.php");

}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    return true; //No options
}

public void onStart() {
    super.onStart();

    stockAdaptor = new StockAdaptor(this); //Create a new StockAdaptor
}

public static String strFromStream(InputStream in) throws IOException { //Simple function, getting a String from an InputStream
    StringBuilder out = new StringBuilder();
    BufferedReader breader = new BufferedReader(new InputStreamReader(in));
    String cline;
    String newLine = System.getProperty("line.separator");
    while ((cline = breader.readLine()) != null) {
        out.append(cline);
        out.append(newLine);
    }
    return out.toString();
}

private class StockAdaptor extends BaseAdapter { //The stocks list adaptor

    class ViewHolder {
        TextView name;
        TextView menu;
        ImageView image; 
    }

    private LayoutInflater layoutInflater;
    private RestaurantInformation[] stocks = null; //Array of stocks
    private ListView stocksListView = null;

    public StockAdaptor(Context context) {
        super();
        layoutInflater = LayoutInflater.from(context);
    }

    public void setStockList(RestaurantInformation[] stocksinfo) {
        this.stocks = stocksinfo;

    }

    @Override
    public int getCount() {
        return stocks.length;
    }

    @Override
    public Object getItem(int position) {
        return stocks[position];
    }
    public RestaurantInformation[] getAll() { //Return the array of stocks
        return stocks;
    }

    @Override
    public long getItemId(int position) {
        return 0;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        ViewHolder holder; //New holder
        if (convertView == null) {
            convertView = layoutInflater.inflate(R.layout.restaurant_information, null);
            holder = new ViewHolder();
            // Creates the new viewHolder define above, storing references to the children
            holder.name = (TextView) convertView.findViewById(R.id.name);
            holder.menu = (TextView) convertView.findViewById(R.id.menu);
            holder.image = (ImageView) convertView.findViewById(R.id.image);



            if (holder.image != null) {
                if (holder.image.getDrawable() == null) {
                    new ImageDownloaderTask(holder.image, null)                                 
                    .execute(stocks[position].image); //Download the image using the image

                }
            }
            convertView.setTag(holder);
        } else {

            holder = (ViewHolder) convertView.getTag();
        }

        holder.name.setText(stocks[position].name);
        holder.menu.setText(stocks[position].menu);

        return convertView;
    }
}

private class JsonReadTask extends AsyncTask<String, Void, String> {

    @Override
    protected String doInBackground(String... params) {
        if (URLUtil.isValidUrl(params[0])) {
            final AndroidHttpClient client = AndroidHttpClient.newInstance("Android");
            final HttpGet getRequest = new HttpGet(params[0]);
            try {
                HttpResponse response = client.execute(getRequest);
                final HttpEntity httpentity = response.getEntity();
                if (httpentity != null){
                    InputStream inputStream = null;
                    try {
                        inputStream = httpentity.getContent();
                        jsonResult = strFromStream(inputStream);
                        Log.i("", jsonResult);
                        return jsonResult;
                    } catch (IllegalArgumentException e) {
                        //
                    } finally {
                        httpentity.consumeContent();
                    }
                }
            } catch (ClientProtocolException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                client.close();
            }
        }
        return null;
    }

    @Override
    protected void onPostExecute(String result) {

        ListDrwaer();
    }

}// end async task

// build hash set for list view
public void ListDrwaer() {
    //Log.d("data from server", "data: " + jsonResult.toString());
    try {
        if (jsonResult!=null) {
            JSONObject jsonResponse = new JSONObject(jsonResult);
            JSONArray jsonMainNode = jsonResponse.optJSONArray("Restaurants");
            Vector<RestaurantInformation> vstocks = new Vector<RestaurantInformation>();

            if(jsonMainNode == null)
            {
                Log.e("If is null", "jsonMainNode is null");
                return;
            }

            for (int i = 0; i < jsonMainNode.length(); i++) {
                JSONObject jsonChildNode = jsonMainNode.getJSONObject(i);
                RestaurantInformation stock = new RestaurantInformation();

                stock.image = jsonChildNode.getString("image");
                stock.name = jsonChildNode.optString("name");
                stock.menu = jsonChildNode.optString("menu");

                //stock.imgPath = jsonChildNode.getString("imgPath");

               Log.e("err", stock.image + " " + stock.name + " " + stock.menu);
               vstocks.add(stock);
            }

            RestaurantInformation[] stocks = new RestaurantInformation[jsonMainNode.length()];

            int stockscount = jsonMainNode.length();
            for (int n = 0; n < stockscount; n++) 
            {               
                stocks[n] = vstocks.get(n);
            }
            stockAdaptor.setStockList(stocks);
            listView.setAdapter(stockAdaptor);
        } else {
            Toast.makeText(getApplicationContext(), "Error; jsonResult null",
                    Toast.LENGTH_SHORT).show();
        }
    } catch (JSONException e) {
        Toast.makeText(getApplicationContext(), "Error" + e.toString(),
                Toast.LENGTH_SHORT).show();
    }
}

private class ImageDownloaderTask extends AsyncTask<String, Void, Bitmap> {
    private final WeakReference<ImageView> imageViewReference;

    public ImageDownloaderTask(ImageView imageView, View view) {
        imageViewReference = new WeakReference<ImageView>(imageView);
    }

    @Override
    // Actual download method, run in the task thread
    protected Bitmap doInBackground(String... params) {
        // params comes from the execute() call: params[0] is the url.
        return downloadBitmap(params[0]);
    }

    @Override
    // Once the image is downloaded, associates it to the imageView
    protected void onPostExecute(Bitmap bitmap) {
        if (isCancelled()) {
            bitmap = null;
        }

        if (imageViewReference != null) {
            ImageView imageView = imageViewReference.get();
            if (imageView != null) {

                if (bitmap != null) {
                    imageView.setImageBitmap(bitmap);
                } else {
                    //
                }
            }

        }

    }

    Bitmap downloadBitmap(String url) {
        if(URLUtil.isValidUrl(url)){

            final AndroidHttpClient client = AndroidHttpClient.newInstance("Android");
            final HttpGet getRequest = new HttpGet(url);
            try {
                HttpResponse response = client.execute(getRequest);
                final int statusCode = response.getStatusLine().getStatusCode();
                if (statusCode != HttpStatus.SC_OK) {
                    Log.w("ImageDownloader", "Error " + statusCode
                            + " while retrieving bitmap from " + url);
                    return null;
                }

                final HttpEntity entity = response.getEntity();
                if (entity != null) {
                    InputStream inputStream = null;
                    try {
                        inputStream = entity.getContent();
                        try {
                            byte[] buffer = new byte[8192];
                            int bytesRead;
                            ByteArrayOutputStream output = new ByteArrayOutputStream();
                            while ((bytesRead = inputStream.read(buffer)) != -1) {
                                output.write(buffer, 0, bytesRead);
                            }   
                            return BitmapFactory.decodeByteArray(output.toByteArray(), 0, output.toByteArray().length);
                        } catch (IllegalArgumentException e) {
                            e.printStackTrace();

                            return null;
                        }
                    } finally {
                        if (inputStream != null) {
                            inputStream.close();
                        }
                        entity.consumeContent();
                    }
                }
            } catch (Exception e) {
                getRequest.abort();
                Log.w("ImageDownloader", "Error while retrieving bitmap from " + url);
            } finally {
                if (client != null) {
                    client.close();
                }
            }
            return null;

        }
        return null;
    }

}
}

我在Java + Android方面经验不足，真的不知道会出现什么问题。这是restaurants.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".Activity" >


    <ImageView
        android:id="@+id/image"
        android:layout_width="70dp"
        android:layout_height="70dp" />

    <ListView
        android:id="@id/android:list"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:layout_alignLeft="@+id/image"
        android:layout_alignParentTop="true" >
    </ListView>

</RelativeLayout>

UPDATE 目标是这样的。我想在左侧和旁边加载图像，以便在可能的情况下使用文本和子文本

enter image description here

更新restaurant_information.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:minHeight="50dp"
android:orientation="vertical" >

<LinearLayout
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal" >

    <ImageView
        android:id="@+id/image"
        android:layout_width="70dp"
        android:layout_height="70dp" />

    <TextView
        android:id="@+id/name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:lineSpacingExtra="3dp"
        android:paddingLeft="5dp"
        android:paddingTop="5dp"
        android:text="" />

    <TextView
        android:id="@+id/menu"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:paddingLeft="5dp"
        android:paddingTop="5dp"
        android:text="" />
</LinearLayout>

Answer 1

您正试图从以下网址下载图片：“rest1.jpg”。您需要一个完整的URL。您可以在json响应中发送完整的url，也可以在代码中添加它（如果文件名前面的部分是固定的）

Answer 2

您的ListView定义为layout_width =“fill_parent”和layout_height =“fill_parent”。因此，它将占用它的父项的整个区域，因为它在布局的最后定义，将位于z顺序的顶部，从而模糊了您的ImageView。

尝试一下：

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".Activity" >

    <ImageView
        android:id="@+id/image"
        android:layout_width="70dp"
        android:layout_height="70dp"
        android:layout_alignParentLeft="true" 
        android:layout_centerVertical="true"/>

    <ListView
        android:id="@id/android:list"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_toRightOf="@+id/image"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true" >
    </ListView>

</RelativeLayout>

图像不显示在ImageView中

2 个答案: