以下是我的代码。我正在尝试将 String image_url 从 SingleMenuItemActivity.class 传递给 SaveImageTask.class 。我还不能完成它。也许我的代码有问题。有人可以检查我的代码。我同时使用 AsyncTask。
SingleMenuItemActivity.class
public class SingleMenuItemActivity extends Activity {
// XML node keys
static final String KEY_TITLE = "title";
static final String KEY_ARTIST = "artist";
static final String KEY_THUMB_URL = "thumb_url";
private ProgressDialog pDialog;
String title;
String artist;
String image_url;
ImageView view;
Intent intent;
Context context;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.single_list_item);
new loadSingleView().execute();
view = (ImageView) findViewById(R.id.single_image);
}
public class loadSingleView extends AsyncTask<String, String, String> {
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(
SingleMenuItemActivity.this);
pDialog.setMessage("Connecting to Server ...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
@Override
protected String doInBackground(String... args) {
// updating UI from Background Thread
Intent in = getIntent();
image_url = in.getStringExtra(KEY_THUMB_URL);
title = in.getStringExtra(KEY_TITLE);
artist = in.getStringExtra(KEY_ARTIST);
return null;
}
@Override
protected void onPostExecute(String args) {
// dismiss the dialog after getting all products
ImageLoader imgLoader = new ImageLoader(getApplicationContext());
imgLoader.DisplayImage(image_url, view);
TextView lblName = (TextView) findViewById(R.id.name_title);
TextView lblCost = (TextView) findViewById(R.id.name_artist);
lblName.setText(title);
lblCost.setText(artist);
pDialog.dismiss();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main_menu, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.save_image:
new SaveImageTask(this).execute(image_url);
return true;
default:
return false;
}
SaveImageTask.class
public class SaveImageTask extends AsyncTask<String , String , String>
{
private Context context;
private ProgressDialog pDialog;
String image_url;
URL myFileUrl = null;
Bitmap bmImg = null;
public SaveImageTask(Context context) {
this.context = context;
}
@Override
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
pDialog = new ProgressDialog(context);
pDialog.setMessage("Downloading Image ...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
@Override
protected String doInBackground(String... args) {
// TODO Auto-generated method stub
try {
myFileUrl = new URL(image_url);
HttpURLConnection conn = (HttpURLConnection) myFileUrl.openConnection();
conn.setDoInput(true);
conn.connect();
InputStream is = conn.getInputStream();
bmImg = BitmapFactory.decodeStream(is);
}
catch (IOException e)
{
e.printStackTrace();
}
try {
String path = myFileUrl.getPath();
String idStr = path.substring(path.lastIndexOf('/') + 1);
File filepath = Environment.getExternalStorageDirectory();
File dir = new File (filepath.getAbsolutePath() + "/Wallpaper/");
dir.mkdirs();
String fileName = idStr;
File file = new File(dir, fileName);
FileOutputStream fos = new FileOutputStream(file);
bmImg.compress(CompressFormat.JPEG, 75, fos);
fos.flush();
fos.close();
}
catch (Exception e)
{
e.printStackTrace();
}
return null;
}
@Override
protected void onPostExecute(String args) {
// TODO Auto-generated method stub
pDialog.dismiss();
}
}