I used the code from the following link: Signare's Blog. I have 10 image URLs and would like to retrieve and show them on my screen. When I use the code from the above link, it's taking more than 10 minutes to load all of the images. How do I speed up this loading?
URLBitmapField post_img= new URLBitmapField(image_url);
add(post_img);
where the class URLBitmapField is defined as:
import net.rim.device.api.math.Fixed32;
import net.rim.device.api.system.Bitmap;
import net.rim.device.api.system.EncodedImage;
import net.rim.device.api.ui.UiApplication;
import net.rim.device.api.ui.component.BitmapField;
public class URLBitmapField extends BitmapField implements URLDataCallback {
EncodedImage result = null;
public static EncodedImage _encoded_img = null;
int _imgWidth = 52;
int _imgHeight = 62;
int _imgMargin = 10;
public URLBitmapField(String url) {
try {
http_image_data_extrator.getWebData(url, this);
}
catch (Exception e) {}
}
public Bitmap getBitmap() {
if (_encoded_img == null) return null;
return _encoded_img.getBitmap();
}
public void callback(final String data) {
if (data.startsWith("Exception")) return;
try {
byte[] dataArray = data.getBytes();
_encoded_img = EncodedImage.createEncodedImage(dataArray, 0, dataArray.length); // with scale
_encoded_img = sizeImage(_encoded_img, _imgWidth, _imgHeight);
setImage(_encoded_img);
UiApplication.getUiApplication().getActiveScreen().invalidate();
}
catch (final Exception e){}
}
public EncodedImage sizeImage(EncodedImage image, int width, int height) {
int currentWidthFixed32 = Fixed32.toFP(image.getWidth());
int currentHeightFixed32 = Fixed32.toFP(image.getHeight());
int requiredWidthFixed32 = Fixed32.toFP(width);
int requiredHeightFixed32 = Fixed32.toFP(height);
int scaleXFixed32 = Fixed32.div(currentWidthFixed32,requiredWidthFixed32);
int scaleYFixed32 = Fixed32.div(currentHeightFixed32,requiredHeightFixed32);
result = image.scaleImage32(scaleXFixed32, scaleYFixed32);
return result;
}
}
public interface URLDataCallback {
public void callback(String data);
}
and the class http_image_data_extrator is defined as:
import java.io.IOException;
import java.io.InputStream;
import javax.microedition.io.Connector;
import javax.microedition.io.HttpConnection;
import net.rim.device.api.system.RadioInfo;
import net.rim.device.api.system.WLANInfo;
import net.rim.device.api.ui.UiApplication;
public class http_image_data_extrator {
static String url_="";
static StringBuffer rawResponse=null;
public static void getWebData(String url, final URLDataCallback callback) throws IOException {
HttpConnection connection = null;
InputStream inputStream = null;
try {
if ((WLANInfo.getWLANState() == WLANInfo.WLAN_STATE_CONNECTED)&& RadioInfo.areWAFsSupported(RadioInfo.WAF_WLAN)) {
url += ";interface=wifi";
}
connection = (HttpConnection) Connector.open(url, Connector.READ, true);
String location=connection.getHeaderField("location");
if(location!=null){
if ((WLANInfo.getWLANState() == WLANInfo.WLAN_STATE_CONNECTED)&& RadioInfo.areWAFsSupported(RadioInfo.WAF_WLAN)) {
location += ";interface=wifi";
}
connection = (HttpConnection) Connector.open(location, Connector.READ, true);
}else{
connection = (HttpConnection) Connector.open(url, Connector.READ, true);
}
inputStream = connection.openInputStream();
byte[] responseData = new byte[10000];
int length = 0;
rawResponse = new StringBuffer();
while (-1 != (length = inputStream.read(responseData))) {
rawResponse.append(new String(responseData, 0, length));
}
int responseCode = connection.getResponseCode();
if (responseCode != HttpConnection.HTTP_OK){
throw new IOException("HTTP response code: "+ responseCode);
}
final String result = rawResponse.toString();
UiApplication.getUiApplication().invokeLater(new Runnable() {
public void run(){
callback.callback(result);
}
});
}
catch (final Exception ex) {
UiApplication.getUiApplication().invokeLater(new Runnable() {
public void run() {
callback.callback("Exception (" + ex.getClass() + "): " + ex.getMessage());
}
});
}
}
}