嘿伙计们，我正在尝试使用数据库中的图像填充列表视图。我已将我的图像上传到服务器并采用http://www.spinner.bl.ee/images/ATE.png之类的完整路径，并将其作为varchar存储在名为image的数据库列中。然后我有一个.php文件，你可以在这里看到http://spinner.bl.ee/getstocks.php给我一个名为metoxes的json数组，包含所有数据。但是图像有点不同（意思是路径）我该如何解决？
在我在imageview中的Android应用程序的java文件中，我获得了完整路径而不是图像。任何帮助将受到高度赞赏！
我的代码
private class JsonReadTask extends AsyncTask<String, Void, String> {
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setTitle(R.string.waiting);
pDialog.setMessage(getString(R.string.get_stocks));
pDialog.setCancelable(false);
pDialog.show();
}
@Override
protected String doInBackground(String... params) {
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost(params[0]);
try {
HttpResponse response = httpclient.execute(httppost);
jsonResult = inputStreamToString(
response.getEntity().getContent()).toString();
}
catch (ClientProtocolException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
private StringBuilder inputStreamToString(InputStream is) {
String rLine = "";
StringBuilder answer = new StringBuilder();
BufferedReader rd = new BufferedReader(new InputStreamReader(is));
try {
while ((rLine = rd.readLine()) != null) {
answer.append(rLine);
}
}
catch (IOException e) {
// e.printStackTrace();
Toast.makeText(getApplicationContext(),
"Error..." + e.toString(), Toast.LENGTH_LONG).show();
}
return answer;
}
@Override
protected void onPostExecute(String result) {
ListDrwaer();
pDialog.dismiss();
}
}// end async task
public void accessWebService() {
JsonReadTask task = new JsonReadTask();
// passes values for the urls string array
task.execute(new String[] { url });
}
// build hash set for list view
public void ListDrwaer() {
List<Map<String, String>> stocksList = new ArrayList<Map<String, String>>();
try {
JSONObject jsonResponse = new JSONObject(jsonResult);
JSONArray jsonMainNode = jsonResponse.optJSONArray("metoxes");
for (int i = 0; i < jsonMainNode.length(); i++) {
JSONObject jsonChildNode = jsonMainNode.getJSONObject(i);
String name = jsonChildNode.optString("name");
String price = jsonChildNode.optString("price");
String image = jsonChildNode.getString("image");
//Log.i("image is valid", image);
//String outPut = name + price;
//BitmapFactory.decodeFile(image);
stocksList.add(createStockList(name, price, image));
}
} catch (JSONException e) {
Toast.makeText(getApplicationContext(), "Error" + e.toString(),
Toast.LENGTH_SHORT).show();
}
//byte[] image = {};
String[] from = { "name", "price", "image" };
//BitmapFactory.decodeByteArray(image, 50, image.length);
int[] to = { R.id.stock_name, R.id.stock_price, R.id.dbImage };
SimpleAdapter simpleAdapter = new SimpleAdapter(this, stocksList,
R.layout.list_item,
from, to);
listView.setAdapter(simpleAdapter);
}
private HashMap<String, String> createStockList(String name, String price, String image) {
HashMap<String, String> stockNameNo = new HashMap<String, String>();
stockNameNo.put("name", name);
stockNameNo.put("price", price);
stockNameNo.put("image", image);
return stockNameNo;
}
}
提前致谢。
答案 0 :(得分：2)
如果问题是您想要以http://www.spinner.bl.ee/images/ATE.png形式出现的数据是http:\/\/spinner.bl.ee\/images\/ATE.png，那么org.json.JSONObject加载字符串时不应该出现问题你的网址是一个JSONObject;你测试过这段代码吗？
以下是一些访问服务器的AsyncTasks的实现;只有一个活动，MainActivity.java，然后是StockInformation.java作为对象。
public class MainActivity extends Activity {
ProgressDialog pDialog;
ListView listView;
private StockAdaptor stockAdaptor;
String jsonResult = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_); //Just a listView, shown below
listView = (ListView) findViewById(android.R.id.list);
new JsonReadTask().execute("http://spinner.bl.ee/getstocks.php"); //YOUR URL JSON SERVER, IF IT IS DIFFERENT FROM THAT SUPPLIED ABOVE
}
@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 price;
ImageView image;
}
private LayoutInflater layoutInflater;
private StockInformation[] stocks = null; //Array of stocks
private ListView stocksListView = null;
public StockAdaptor(Context context) {
super();
layoutInflater = LayoutInflater.from(context);
}
public void setStockList(StockInformation[] stocksinfo) {
this.stocks = stocksinfo;// //////////////LITERALLY THIS
}
@Override
public int getCount() {
return stocks.length;
}
@Override
public Object getItem(int position) {
return stocks[position];
}
public StockInformation[] 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.list_item,
null);
holder = new ViewHolder();
// Creates the new viewholder define above, storing references to the children
holder.name = (TextView) convertView.findViewById(R.id.name);
holder.price = (TextView) convertView.findViewById(R.id.price);
holder.image = (ImageView) convertView.findViewById(R.id.image);
stocksListView = (ListView) findViewById(android.R.id.list);
if (holder.image != null) {
if (holder.image.getDrawable() == null) {
new ImageDownloaderTask(holder.image, null) .execute(stocks[position].imageurl); //Download the image using the imageurl
}
}
convertView.setTag(holder);
} else {
stocksListView = (ListView) findViewById(android.R.id.list);
holder = (ViewHolder) convertView.getTag();
}
holder.name.setText(stocks[position].name);
holder.price.setText(stocks[position].price);
return convertView;
}
}
private class JsonReadTask extends AsyncTask<String, Void, String> {
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setTitle("waiting");
pDialog.setMessage("getting stocks");
pDialog.setCancelable(false);
pDialog.show();
}
@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();
pDialog.dismiss();
}
}// end async task
// build hash set for list view
public void ListDrwaer() {
try {
if (jsonResult!=null) {
JSONObject jsonResponse = new JSONObject(jsonResult);
JSONArray jsonMainNode = jsonResponse.optJSONArray("metoxes");
Vector<StockInformation> vstocks = new Vector<StockInformation>();
for (int i = 0; i < jsonMainNode.length(); i++) {
JSONObject jsonChildNode = jsonMainNode.getJSONObject(i);
StockInformation stock = new StockInformation();
stock.name = jsonChildNode.optString("name");
stock.price = jsonChildNode.optString("price");
stock.imageurl = jsonChildNode.getString("image");
Log.i("StockLog", stock.name + stock.price + stock.imageurl);
vstocks.add(stock);
}
StockInformation[] stocks = new StockInformation[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();
Log.i("IAE", "in stocks");
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;
}
}
}
单独定义：StockInformation.java;股票对象。
public class StockInformation {
public String name;
public String price;
public String imageurl;
}
然后是xml文件：activity_.xml（仅包含ListView）;
<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" >
<ListView
android:id="@+id/android:list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"/>
</RelativeLayout>
和list_item.xml（只是图片和每个股票所需的两个文本）：
<?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/price"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingLeft="5dp"
android:paddingTop="5dp"
android:text="" />
</LinearLayout>
</LinearLayout>