I'm using AsyncTask to perform an operation that connects to internet, download data, and then get a picture of the internet.
The image obtained from internet too, but when it takes the server to respond the application gets a FC.
How I can do to get the data AsyncTask although it takes the server?
Then I put the code I use to download the data:
class CargaImgs extends AsyncTask<Void, Void, Bitmap> {
final ProgressDialog progressDialog = new ProgressDialog(imagen.this);
protected void onPreExecute() {
progressDialog.setTitle("");
progressDialog.setMessage("Cargando Imagen...");
progressDialog.show();
}
protected Bitmap doInBackground(Void... params) {
return urlImageToBitmap(imageUrl(StrUrl));
}
protected void onPostExecute(Bitmap imagen) {
RawBmp = imagen;
sourceBmp = RawBmp;
sourceBmp = redimensionarImagenMaximo(sourceBmp, screen_w, screen_h);
imageWidth = sourceBmp.getWidth();
imageHeight = sourceBmp.getHeight();
showBmp = Bitmap.createBitmap(sourceBmp);
main.invalidate();
primera_carga = false;
progressDialog.dismiss();
}
}
private String imageUrl(String url) {
Document doc = null;
try {
doc = Jsoup.connect(url).get();
} catch (IOException e1) {
e1.printStackTrace();
}
Elements div_exterior = doc.getElementsByClass("inner");
for (Element subelementos : div_exterior) {
Elements imgs = subelementos.getElementsByTag("img");
StrUrlImage = imgs.get(1).attr("src");
if (StrUrlImage == StrUrlImage2) {
} else {
return imgs.get(1).attr("src");
}
}
return null;
}
public Bitmap urlImageToBitmap(String urlImage) {
Bitmap mIcon1 = null;
URL url_value;
try {
url_value = new URL(urlImage);
if (url_value != null) {
mIcon1 = BitmapFactory.decodeStream(url_value.openConnection()
.getInputStream());
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return mIcon1;
}
avoid using main.invalidate() as it paints(draw whole view again--each time you execute AsyncTask)
Rather, set bitmap to the desired view or invalidate that view only.
public Bitmap urlImageToBitmap(String urlImage) {
Bitmap mIcon1 = null;
URL url_value;
try {
url_value = new URL(urlImage);
if (url_value != null) {
URLConnection conn = url_value.openConnection();
conn.setConnectTimeout(10000);
mIcon1 = BitmapFactory.decodeStream(conn.getInputStream());
}
} catch (SocketTimeoutException e) {
e.printStackTrace();
}catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return mIcon1;
}
And regarding postExecute, if there is exception in doInBackground, it will return null, and that may lead to null pointer exception. So handle that in post execute.
Related
I want to show a default picture when the result is null and here is my try:
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);
connection.disconnect();
return myBitmap;
} catch (IOException e) {
// tasvirdimg.setImageResource(R.drawable.p3_books);
e.printStackTrace();
return null;
}
}
}
a class to use getBitmapFromURL:
class RetrievePic extends AsyncTask<String, String, Bitmap>{
#Override
protected Bitmap doInBackground(String... urls) {
String url = urls[0];
return JSONCommands.getBitmapFromURL(url);
}
}
execute RetrievePic class in ListAdapter:
RetrievePic retPic = new RetrievePic();
retPic.execute(JSONCommands.firstURL + MainActivity.books_array.get(position).tasvir);
Bitmap img = null;
try {
img = retPic.get();
} catch (InterruptedException e) {
// TODO Auto-generated catch block
tasvirlimg.setImageResource(R.drawable.p3_books);
e.printStackTrace();
} catch (ExecutionException e) {
// TODO Auto-generated catch block
tasvirlimg.setImageResource(R.drawable.p3_books);
e.printStackTrace();
}
tasvirlimg.setImageBitmap(img);
when the picture is null it doesn't show any thing but it should show the default picture which is R.drawable.p3_books. thanks to your helps.
what you want to do is in your implementation of your adapter's getView() method, something like this,
...
final imageView = ...;
imageView.setImageBitmap(defaultBitmap);
new AsyncTask<Void,Void,Bitmap>() {
public Bitmap doInBackground(Void... params) {
// get bitmap from `net, or return null if failure
}
public void onPostExecute(Bitmap result) {
if (result != null) {
imageView.setBitmap(result);
}
}
}.execute();
this way, the default is set. if you happen to get the network result, change the default.
You could try this:
if(img == null)
{
tasvirlimg.setImageDrawable(R.drawable.p3_books);
}
else
{
tasvirlimg.setImageBitmap(img);
}
Why not set the default pic of item in xml and then the default pic would be replaced when result is not null
<ImageView
...
android:src="#drawable/p3_books"
/>
EDIT:
class RetrievePic extends AsyncTask<String, String, Bitmap>{
final image = (ImageView) findViewById(R.id.limg_tasvir);
#Override
protected Bitmap doInBackground(String... urls) {
String url = urls[0];
return JSONCommands.getBitmapFromURL(url);
}
#Override
protected void onPreExecute() {
runOnUiThread(new Runnable() {
#Override
public void run() {
image.setBackgroundResource(R.drawable.p3_books);
}
});
}
}
I'm trying to use WallpaperManager in a ViewPager. I've got a button which is supposed to set the current image in the ViewPager to wallpaper. My problem comes with the line of code wallpManager.setResource(newInt);... the integer it comes up with is always 0 (zero), and so the app crashes and LogCat says there's no Resource at ID #0x0. As a test to see if I'm getting the correct image URL I've done this:
String newStr = images[position];
CharSequence cs = newStr;
Toast.makeText(UILPager.this, cs, Toast.LENGTH_SHORT).show();
And the resulting Toast shows the correct image URL. I can't figure out how to convert the URL which is in the form of "http://www.example.com/image.jpg" to an Integer so that the WallpaperManager can use it. Here's what the whole button code looks like:
wallp_BTN.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
WallpaperManager wallpManager = WallpaperManager.getInstance(getApplicationContext());
String newStr = images[position];
int newInt = 0;
try{
newInt = Integer.parseInt(newStr);
} catch(NumberFormatException nfe) {
}
CharSequence cs = newStr;
try {
wallpManager.setResource(newInt);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
Toast.makeText(UILPager.this, cs, Toast.LENGTH_SHORT).show();
}
});
Set wallpaper from URL
try {
URL url = new URL("http://developer.android.com/assets/images/dac_logo.png");
Bitmap bitmap = BitmapFactory.decodeStream(url.openStream());
wallpaperManager.setBitmap(bitmap);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
Enjoy =)
A method wallpaperManager.setResource() requires resource id from your application. Example: I've ImageView with id "myImage" then call the method will look like as wallpaperManager.setResource(R.id.myImage).
In your case your id not valid.
Instead of wallpManager.setResource(0) you should use the wallpManager.setResource(R.drawable.yourimage) since it's expecting a drawable and there is none in your app with id = 0.
In your code
String newStr = images[position];
int newInt = 0;
try{
newInt = Integer.parseInt(newStr);
} catch(NumberFormatException nfe) {
}
Since newStr is never a number, always a url so NumberFormatException is caught always. Hence the value of newInt is always initialized to 0. Hence the error.
I realized that I have to download the image before I can set it as wallpaper! Thanks for your help AndroidWarrior and Owl. When I get the download code worked out, I'll post it. Owl showed me how to download the wallpaper:
//--- Wallpaper button
wallp_BTN.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
try {
vpURL = new URL(images[position]);
} catch (MalformedURLException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
WallpaperManager wallpManager = WallpaperManager.getInstance(getApplicationContext());
try {
Bitmap bitmap = BitmapFactory.decodeStream(vpURL.openStream());
wallpManager.setBitmap(bitmap);
Toast.makeText(UILPager.this, "The wallpaper has been set!", Toast.LENGTH_LONG).show();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
});
//--- END Wallpaper button
... and I also figured out how to download the ViewPager image as well (I need to do both in different areas of my app):
//--- Wallpaper button
wallp_BTN.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
String vpURLStr = images[position];
GetVPImageTask downloadVPImageTask = new GetVPImageTask();
downloadVPImageTask.execute(new String[] { vpURLStr });
}
});
//--- END Wallpaper button
//--- Download ViewPager Image AsyncTask
private class GetVPImageTask extends AsyncTask<String, Void, Bitmap> {
ProgressDialog getVPImageDia;
#Override
protected void onPreExecute() {
super.onPreExecute();
getVPImageDia = new ProgressDialog(UILNPPager.this);
getVPImageDia.setMessage("Grabbing the image...");
getVPImageDia.setIndeterminate(false);
getVPImageDia.show();
}
#Override
protected Bitmap doInBackground(String... urls) {
Bitmap map = null;
for (String url : urls) {
map = downloadImage(url);
}
return map;
}
// Sets the Bitmap returned by doInBackground
#Override
protected void onPostExecute(Bitmap result) {
try {
getVPImageDia.dismiss();
getVPImageDia = null;
} catch (Exception e) {
// nothing
}
Toast.makeText(UILNPPager.this, "The image be Downloaded!", Toast.LENGTH_SHORT).show();
//downloaded_iv.setImageBitmap(result);
}
// Creates Bitmap from InputStream and returns it
private Bitmap downloadImage(String url) {
Bitmap bitmap = null;
InputStream stream = null;
BitmapFactory.Options bmOptions = new BitmapFactory.Options();
bmOptions.inSampleSize = 1;
try {
stream = getHttpConnection(url);
bitmap = BitmapFactory.
decodeStream(stream, null, bmOptions);
stream.close();
} catch (IOException e1) {
e1.printStackTrace();
}
return bitmap;
}
// Makes HttpURLConnection and returns InputStream
private InputStream getHttpConnection(String urlString)
throws IOException {
InputStream stream = null;
URL url = new URL(urlString);
URLConnection connection = url.openConnection();
try {
HttpURLConnection httpConnection = (HttpURLConnection) connection;
httpConnection.setRequestMethod("GET");
httpConnection.connect();
if (httpConnection.getResponseCode() == HttpURLConnection.HTTP_OK) {
stream = httpConnection.getInputStream();
}
} catch (Exception ex) {
ex.printStackTrace();
}
return stream;
}
}
//--- END Download ViewPager Image AsyncTask
I'm having some troubles displaying an image I am fetching from a URL into an ImageView. With the code I have at the moment, I am getting absolutely nothing. Is there a problem with this code?
Drawable img = image.LoadImageFromWeb(icon);
imageView.setImageDrawable(img);
public static Drawable LoadImageFromWeb(String iconId) {
try {
String url = "http://ddragon.leagueoflegends.com/cdn/4.3.12/img/profileicon/" + iconId + ".png";
InputStream is = (InputStream) new URL(url).getContent();
Drawable icon = Drawable.createFromStream(is, "src name");
return icon;
} catch (Exception e) {
return null;
}
}
try this function
private void downloadImage()
{
Bitmap bitmap = null;
try {
URL urlImage = new
URL("http://ddragon.leagueoflegends.com/cdn/4.3.12/img/profileicon/" + iconId +
".png");
HttpURLConnection connection = (HttpURLConnection)
urlImage.openConnection();
InputStream inputStream = connection.getInputStream();
//****bitmap is your image*****
bitmap = BitmapFactory.decodeStream(inputStream);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
and use asyncTask to wait until downloading the image like this
private class Asyn_SaveData extends AsyncTask<Void, Void, Void> {
#Override
protected Void doInBackground(Void... params) {
//get the random string from prefs
if (context != null)
downloadImage();
return null;
}
#Override
protected void onPostExecute(Void result) {
// TODO Auto-generated method stub
super.onPostExecute(result);
//do what you want after the image downloaded
}
}
Note: AsyncTask must be subClassed, and after the doInBackground finish its job it calls automatically the onPostExecute
In my app, when you click on the button then I am downloading the images from the url's. It displaying the images some time correctly but some time it display empty. *problem is some times bitmap object(i.e, "result" in code ) return null.*please can anybody help me.
Following is my code
try
{
String ImageUrl = ((eachReview)RB_Constant.revht.get(title_value)).UserImageUrl;
System.out.println("Image Url:"+ImageUrl);
if(ImageUrl != null)
{
DownLoadImageInAThreadHandler(ImageUrl,holder);
}
else
{
System.out.println("Image url is null then display the default image");
holder.userImage.setImageResource(R.drawable.defaultuserimage);
}
}
catch(Exception e){
System.out.println("Error from Userimage fetching.."+e.toString());
}
private void DownLoadImageInAThreadHandler(final String imgurl,final ViewHolder holder)
{
//Thread for getting the attributes values
Thread t = new Thread()
{
public void run()
{
try
{
Bitmap drawable = getDrawableFromUrl(imgurl);
System.out.println("Drawable(after downloading):"+drawable);
if(drawable != null)
{
holder.userImage.setImageBitmap(drawable);
}
else
{
System.out.println("after downloading drawable is null then set the default image");
holder.userImage.setImageResource(R.drawable.defaultuserimage);
}
}
catch(Exception exp)
{
System.out.println("Exception in DownLoadImageInAThread : " + exp.getMessage());
}
}
private Bitmap getDrawableFromUrl(String imageUrl)
{
try
{
URL myFileUrl = new URL(imageUrl);
HttpURLConnection conn = (HttpURLConnection) myFileUrl.openConnection();
conn.setDoInput(true);
conn.connect();
InputStream is = conn.getInputStream();
final Bitmap result = BitmapFactory.decodeStream(is);
is.close();
new Thread() {
public void run() {
ByteArrayOutputStream bytes = new ByteArrayOutputStream();
if(result != null)
{
result.compress(Bitmap.CompressFormat.JPEG, 40, bytes);
}
}
}.start();
return result;
}
catch (FileNotFoundException e)
{
e.printStackTrace();
}
catch (MalformedURLException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}
return null;
}
};
t.start();
}
Try making you getDrawableFromUrl as:
public static Drawable getDrawableFromUrl(String url) {
Drawable image = null;
try {
InputStream in = (java.io.InputStream) new java.net.URL(url).getContent();
if (in != null) {
image = Drawable.createFromStream(in, "image");
in.close();
}
} catch (Exception ex) {
ex.printStackTrace();
}
return image;
}
Also do not compress image within same function. Try Doing it after you successfully receive an image. One thing more that write getDrawableFromUrl function out of the thread but in same class. Hope this works for you.
I used the code below to fetch the image from a url but it doesn't working for large images.
Am I missing something when fetching that type of image?
imgView = (ImageView)findViewById(R.id.ImageView01);
imgView.setImageBitmap(loadBitmap("http://www.360technosoft.com/mx4.jpg"));
//imgView.setImageBitmap(loadBitmap("http://sugardaddydiaries.com/wp-content/uploads/2010/12/how_do_i_get_sugar_daddy.jpg"));
//setImageDrawable("http://sugardaddydiaries.com/wp-content/uploads/2010/12/holding-money-copy.jpg");
//Drawable drawable = LoadImageFromWebOperations("http://www.androidpeople.com/wp-content/uploads/2010/03/android.png");
//imgView.setImageDrawable(drawable);
/* try {
ImageView i = (ImageView)findViewById(R.id.ImageView01);
Bitmap bitmap = BitmapFactory.decodeStream((InputStream)new URL("http://sugardaddydiaries.com/wp-content/uploads/2010/12/holding-money-copy.jpg").getContent());
i.setImageBitmap(bitmap);
} catch (MalformedURLException e) {
System.out.println("hello");
} catch (IOException e) {
System.out.println("hello");
}*/
}
protected Drawable ImageOperations(Context context, String string,
String string2) {
// TODO Auto-generated method stub
try {
InputStream is = (InputStream) this.fetch(string);
Drawable d = Drawable.createFromStream(is, "src");
return d;
} catch (MalformedURLException e) {
e.printStackTrace();
return null;
} catch (IOException e) {
e.printStackTrace();
return null;
}
}
You're trying to download the Large Image from within the UI Thread....This will cause an ANR (Application not Responding)
Use AsyncTask to download the images, that way, a seperate thread will be used for the download and your UI Thread wont lock up.
see this good example that loads image from server.
blog.sptechnolab.com/2011/03/04/android/android-load-image-from-url/.
If you want to download the image very quickly then you can use AQuery which is similar to JQuery just download the android-query.0.15.7.jar
Import the jar file and add the following snippet
AQuery aq = new AQuery(this);
aq.id(R.id.image).image("http://4.bp.blogspot.com/_Q95xppgGoeo/TJzGNaeO8zI/AAAAAAAAADE/kez1bBRmQTk/s1600/Sri-Ram.jpg");
// Here R.id.image is id of your ImageView
// This method will not give any exception
// Dont forgot to add Internet Permission
public class MyImageActivity extends Activity
{
private String image_URL= "http://home.austarnet.com.au/~caroline/Slideshows/Butterfly_Bitmap_Download/slbutfly.bmp";
private ProgressDialog pd;
private Bitmap bitmap;
private ImageView bmImage;
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
bmImage = (ImageView)findViewById(R.id.imageview);
pd = ProgressDialog.show(this, "Please Wait", "Downloading Image");
DownloadWebPageTask task = new DownloadWebPageTask();
task.execute(new String[] { image_URL });
// You can also give more images in string array
}
private class DownloadWebPageTask extends AsyncTask<String, Void, Bitmap>
{
// String --> parameter in execute
// Bitmap --> return type of doInBackground and parameter of onPostExecute
#Override
protected Bitmap doInBackground(String...urls) {
String response = "";
for (String url : urls)
{
InputStream i = null;
BufferedInputStream bis = null;
ByteArrayOutputStream out =null;
// Only for Drawable Image
// try
// {
// URL url = new URL(image_URL);
// InputStream is = url.openStream();
// Drawable d = Drawable.createFromStream(is, "kk.jpg");
// bmImage.setImageDrawable(d);
// }
// catch (Exception e) {
// // TODO: handle exception
// }
// THE ABOVE CODE IN COMMENTS WILL NOT WORK FOR BITMAP IMAGE
try
{
URL m = new URL(image_URL);
i = (InputStream) m.getContent();
bis = new BufferedInputStream(i, 1024*8);
out = new ByteArrayOutputStream();
int len=0;
byte[] buffer = new byte[4096];
while((len = bis.read(buffer)) != -1)
{
out.write(buffer, 0, len);
}
out.close();
bis.close();
byte[] data = out.toByteArray();
bitmap = BitmapFactory.decodeByteArray(data, 0, data.length);
}
catch (Exception e)
{
e.printStackTrace();
}
}
return bitmap;
}
#Override
protected void onPostExecute(Bitmap result)
{
if(result!=null)
bmImage.setImageBitmap(result);
pd.dismiss();
}
}
}