我的布局上有后退按钮，每次点击都会调用对话框。单击时，我首先检查进度对话框是否可见，即异步任务是否正在运行，如果是，则比单击是按钮单击对话框时，我正在调用新活动。它工作正常，但我反复收到错误，例如单击此后退按钮时 Activity has Memory Leak。请提出一些解决方法来克服这个问题。这里是片段
public class LatestTab extends Activity {
Activity context;
ArrayList<String> contentList,slugList,latestData,imgLinks;
ArrayList<HashMap<String, String>> mylist;
JSONObject json, obj,img,thumb;
JSONArray latest, attachment;
ImageView bck;
String shareUrl = "-- url ----";
String jString;
ProgressBar showProgress;
NetworkCheck netCheck;
File externalFile = new File(Environment.getExternalStorageDirectory(),"Latest.txt");
ListView listView;
String imgStr;
ImageLoader loader;
LazyAdapter lazyAdapter;
String latestUrl = "---url--";
Bundle bundle;
boolean isFinish = true;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
/*this.requestWindowFeature(Window.FEATURE_NO_TITLE);*/
setContentView(R.layout.activity_latest_tab);
context = this;
bck = (ImageView) findViewById(R.id.bckbtn);
showProgress= (ProgressBar)findViewById(R.id.showProgress);
netCheck = new NetworkCheck(context);
listView = (ListView) findViewById(R.id.latestList);
latestData = new ArrayList<String>();
imgLinks = new ArrayList<String>();
mylist = new ArrayList<HashMap<String, String>>();
contentList = new ArrayList<String>();
slugList = new ArrayList<String>();
bundle = getIntent().getExtras();
if(bundle != null){
isFinish = bundle.getBoolean("finishAct");
}
MyAsyncTask my = new MyAsyncTask();
if(netCheck.isNetworkAvailable()){
showProgress.setVisibility(View.VISIBLE);
my.execute(latestUrl);
}else{
//Toast.makeText(context, "No Internet Connection", Toast.LENGTH_SHORT).show();
try {
FileInputStream filename = null;
Document xmldoc = null;
DocumentBuilderFactory doc_build_fact = null;
DocumentBuilder doc_builder = null;
filename = new FileInputStream("/sdcard/MadhuriLatest.txt");
if(externalFile.exists()){
// Toast.makeText(context, "File Excits", Toast.LENGTH_SHORT).show();
FileChannel fc = filename.getChannel();
MappedByteBuffer bb = fc.map(FileChannel.MapMode.READ_ONLY, 0, fc.size());
jString = Charset.defaultCharset().decode(bb).toString();
json = new JSONObject(jString);
latest = json.getJSONArray("posts");
imgLinks.clear();
latestData.clear();
for(int i=0;i<latest.length();i++){
HashMap<String, String> map = new HashMap<String, String>();
JSONObject e = latest.getJSONObject(i);
String name = e.getString("title_plain");
String content = e.getString("content");
attachment = e.getJSONArray("attachments");
for(int p=0; p<attachment.length();p++){
obj = attachment.getJSONObject(p);
img = obj.getJSONObject("images");
thumb = img.getJSONObject("thumbnail");
imgStr = thumb.getString("url");
}
Log.d("--------------",imgStr);
contentList.add(content);
String chng = "–";
String fnl_Str = name.replace(chng, "");
latestData.add(fnl_Str);
imgLinks.add(imgStr);
String slug = e.getString("slug");
slugList.add(slug);
map.put("id", String.valueOf(i));
map.put("name", fnl_Str);
map.put("date", e.getString("date"));
mylist.add(map);
}
}
lazyAdapter = new LazyAdapter(context, imgLinks, latestData);
listView.setAdapter(lazyAdapter);
lazyAdapter.notifyDataSetChanged();
listView.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent intent=new Intent(context,WebViewActivity.class);
intent.putExtra("content", contentList.get(position));
intent.putExtra("shareUrl", shareUrl+slugList.get(position));
intent.putExtra("tab_value", 1);
startActivity(intent);
overridePendingTransition(R.anim.lefttorightslide,R.anim.righttoleftslide);
}
});
}catch(JSONException e) {
Log.e("log_tag", "Error parsing data "+e.toString());
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}catch (Exception e){
Log.e("Error: ", " "+e.getMessage());
}
}
bck.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
if(showProgress.isShown()){
final Dialog dialog = new Dialog(context, android.R.style.Theme_Translucent_NoTitleBar);
//final Dialog dialog = new Dialog(LAtestTab.this);
dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
/*dialog.getWindow().setBackgroundDrawableResource(R.drawable.alert_box);*/
dialog.setContentView(R.layout.alertbox);
ImageView yes = (ImageView) dialog.findViewById(R.id.yesbtn);
ImageView no = (ImageView) dialog.findViewById(R.id.nobtn);
dialog.show();
yes.setOnClickListener(new OnClickListener()
{
@Override
public void onClick(View v)
{
if(isFinish){
Intent intent = new Intent(context,MadhuriHomeScreen.class);
startActivity(intent);
overridePendingTransition(R.anim.slide_out_left,R.anim.slide_out_right);
finish();
}else{
finish();
}
}
});
no.setOnClickListener(new OnClickListener()
{
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
dialog.dismiss();
}
});
}
else{
finish();
}
}
});
}
class MyAsyncTask extends AsyncTask<String, Integer, ArrayList<HashMap<String, String>> > {
@Override
protected ArrayList<HashMap<String, String>> doInBackground(
String... params) {
// TODO Auto-generated method stub
int count;
mylist = new ArrayList<HashMap<String, String>>();
contentList=new ArrayList<String>();
slugList=new ArrayList<String>();
/*json = new JSONObject();*/
json = JSONfunctions.getJSONfromURL(latestUrl);
try{
URL url = new URL(params[0]);
URLConnection connection = url.openConnection();
connection.connect();
// getting file length
int lenghtOfFile = connection.getContentLength();
// input stream to read file - with 8k buffer
InputStream input = new BufferedInputStream(url.openStream(), 8192);
// Output stream to write file
FileOutputStream output = new FileOutputStream("/sdcard/MadhuriLatest.txt");
byte data[] = new byte[1024];
long total = 0;
while ( ((count = input.read(data)) != -1) ) {
total += count;
// publishing the progress....
// After this onProgressUpdate will be called
/* publishProgress(""+(int)((total*100)/lenghtOfFile));
*/
// writing data to file
output.write(data, 0, count);
}
output.flush();
// closing streams
output.close();
input.close();
latest = json.getJSONArray("posts");
imgLinks.clear();
for(int i=0;i<latest.length();i++){
HashMap<String, String> map = new HashMap<String, String>();
JSONObject e = latest.getJSONObject(i);
String name = e.getString("title_plain");
String content = e.getString("content");
attachment = e.getJSONArray("attachments");
for(int p=0; p<attachment.length();p++){
obj = attachment.getJSONObject(p);
img = obj.getJSONObject("images");
thumb = img.getJSONObject("thumbnail");
imgStr = thumb.getString("url");
}
Log.d("--------------",imgStr);
contentList.add(content);
String chng = "–";
String fnl_Str = name.replace(chng, "");
String slug = e.getString("slug");
slugList.add(slug);
latestData.add(fnl_Str);
imgLinks.add(imgStr);
map.put("id", String.valueOf(i));
map.put("name", fnl_Str);
map.put("date", e.getString("date"));
mylist.add(map);
}
}catch(ConnectionClosedException con){
Toast.makeText(context, "Connextion Closed", Toast.LENGTH_SHORT).show();
}catch(ConnectTimeoutException timeOut){
Toast.makeText(context, "Connextion Time out", Toast.LENGTH_SHORT).show();
Log.d("******************", "connection time out");
}catch(JSONException e){
Log.e("log_tag", "Error parsing data "+e.toString());
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
catch (Exception e){
Log.e("Error: ", " "+e.getMessage());
}
return mylist;
}
@Override
protected void onPostExecute(ArrayList<HashMap<String, String>> result) {
showProgress.setVisibility(View.GONE);
lazyAdapter = new LazyAdapter(context, imgLinks, latestData);
listView.setAdapter(lazyAdapter);
lazyAdapter.notifyDataSetChanged();
listView.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent intent=new Intent(context,WebViewActivity.class);
intent.putExtra("content", contentList.get(position));
intent.putExtra("shareUrl", shareUrl+slugList.get(position));
intent.putExtra("tab_value", 1);
startActivity(intent);
overridePendingTransition(R.anim.lefttorightslide,R.anim.righttoleftslide);
}
});
}
@Override
protected void onPreExecute() {
// TODO Auto-generated method stub
super.onPreExecute();
showProgress.setVisibility(View.VISIBLE);
}
@Override
protected void onProgressUpdate(Integer... values) {
// TODO Auto-generated method stub
super.onProgressUpdate(values);
showProgress.setVisibility(View.VISIBLE);
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_latest_tab, menu);
return true;
}
@Override
public void onBackPressed() {
// TODO Auto-generated method stub
if(isFinish){
Intent intent = new Intent(context,MadhuriHomeScreen.class);
startActivity(intent);
overridePendingTransition(R.anim.slide_out_left,R.anim.slide_out_right);
finish();
}else{
super.onBackPressed();
overridePendingTransition(R.anim.slide_out_left,R.anim.slide_out_right);
}
}
}
这是LogTrace ..
12-17 13:00:36.964: E/WindowManager(9512): Activity com.phonethics.example.LatestTab has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@2c444278 that was originally added here
12-17 13:00:36.964: E/WindowManager(9512): android.view.WindowLeaked: Activity com.phonethics.madhuridixitnene.DanceTab has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@2c444278 that was originally added here
12-17 13:00:36.964: E/WindowManager(9512): at android.view.ViewRootImpl.<init>(ViewRootImpl.java:344)
12-17 13:00:36.964: E/WindowManager(9512): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:267)
12-17 13:00:36.964: E/WindowManager(9512): at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:215)
12-17 13:00:36.964: E/WindowManager(9512): at android.view.WindowManagerImpl$CompatModeWrapper.addView(WindowManagerImpl.java:140)
12-17 13:00:36.964: E/WindowManager(9512): at android.view.Window$LocalWindowManager.addView(Window.java:537)
12-17 13:00:36.964: E/WindowManager(9512): at android.app.Dialog.show(Dialog.java:278)
12-17 13:00:36.964: E/WindowManager(9512): at com.phonethics.example.LatestTab.onClick(LatestTab.java:243)
12-17 13:00:36.964: E/WindowManager(9512): at android.view.View.performClick(View.java:3534)
12-17 13:00:36.964: E/WindowManager(9512): at android.view.View$PerformClick.run(View.java:14263)
12-17 13:00:36.964: E/WindowManager(9512): at android.os.Handler.handleCallback(Handler.java:605)
12-17 13:00:36.964: E/WindowManager(9512): at android.os.Handler.dispatchMessage(Handler.java:92)
12-17 13:00:36.964: E/WindowManager(9512): at android.os.Looper.loop(Looper.java:137)
12-17 13:00:36.964: E/WindowManager(9512): at android.app.ActivityThread.main(ActivityThread.java:4441)
12-17 13:00:36.964: E/WindowManager(9512): at java.lang.reflect.Method.invokeNative(Native Method)
12-17 13:00:36.964: E/WindowManager(9512): at java.lang.reflect.Method.invoke(Method.java:511)
12-17 13:00:36.964: E/WindowManager(9512): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
12-17 13:00:36.964: E/WindowManager(9512): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
12-17 13:00:36.964: E/WindowManager(9512): at dalvik.system.NativeStart.main(Native Method)