I have done this with the help of a boolean arraylist maintaining the state of the check boxes
On Wed, Jul 27, 2011 at 10:23 PM, Simon Platten < [email protected]> wrote: > In a nutshell as was said by the last poster, the listview re-uses the > same objects over and over for those items on view. In your adapter you can > have an array which contains the entire content but you should be very > careful that you aren't storing to much in this array, for example don't > attempt to hold all your images in memory, chances are it will fail at some > point. Below is a "work in progress" from my application, I've added a few > more comments to make it a bit clearer whats going on: > > > public View getView(int position, > View convertView, > ViewGroup parent) { > View vi = convertView; > > try{ > // Get a reference to the actual element from the big array, this array > contains all the items that will be shown in the listview, but note the > array only stores file names, not images > imgFile objActual = m_aryImages.get(position); > // This is a temporary reference that will be used to ref to the item on > view from the list, this is not the same as objects in the array > imgFile objOnView; > > if ( vi == null ) { > // If we get here then this is the first time that this object has been > created, each 'visible' item in the listview will get here. > vi = m_layoutInfater.inflate(R.layout.lvimages, null); > // Create a new object for this item, these are recycled when the listview > is scrolled. > objOnView = new imgFile(); > // Set-up references to all the controls in the item > > objOnView.setThumbnail((ImageView)vi.findViewById(R.id.ivthumbNail)); > > objOnView.setUseCheckBox((CheckBox)vi.findViewById(R.id.chkUse)); > > objOnView.setCCWbutton((ImageButton)vi.findViewById(R.id.btnCCW)); > > objOnView.setCWbutton((ImageButton)vi.findViewById(R.id.btnCW)); > // Add a reference to the object > vi.setTag(objOnView); > } else { > // Get the object from the list view that we will recycle for the next > view > objOnView = (imgFile)vi.getTag(); > } > // In the temporary objects in the listview I store the actual LV index so > I can compare before they get recycle, helps to transfer information back to > the large array. > int intArrayRef = objOnView.getLVindex(); > > if ( intArrayRef != imgFile.NO_REF && intArrayRef < > m_aryImages.size() ) { > // If we get here it means the object has been used before and is about to > be recycled, so I transfer the information from the temporary object back > into the array. > imgFile objOriginal = m_aryImages.get(intArrayRef); > objOriginal.setUse(objOnView.getUse()); > objOriginal.setAngle(objOnView.getAngle()); > } > // Make sure the listview index is up to date for next time > objOnView.setLVindex(position); > // Get the properties of the actual array entry and populate the list view > object > String strFullPath = objActual.getFilename(); > > // Set-up the text view with just the file name > String[] aryFile = uwrTabActivity.splitPath(strFullPath); > > if ( aryFile == null ) { > throw new Exception( "Cannot split image path!" ); > } > // Transfer the data from the actual object to the object on view > > objOnView.setFilename(objActual.getFilename()); > objOnView.setUse(objActual.getUse()); > objOnView.setAngle(objActual.getAngle()); > // Set-up the use check-box > CheckBox cbUse = objOnView.getUseCheckBox(); > cbUse.setText(aryFile[1]); > cbUse.setChecked(objActual.getUse()); > cbUse.setTag(objOnView); > cbUse.setOnClickListener(new OnClickListener() { > @Override > public void onClick(View v) { > CheckBox cb = (CheckBox)v; > imgFile ii = (imgFile)v.getTag(); > ii.setUse(cb.isChecked()); > > } > }); > // Set-up rotation buttons with listeners > ImageButton btn = objOnView.getCCWbutton(); > btn.setTag(objOnView); > btn.setOnClickListener(new OnClickListener() { > @Override > public void onClick(View v) { > ImageButton ibtn = (ImageButton)v; > imgFile ii = (imgFile)ibtn.getTag(); > ii.rotateThumbnail(imgFile.ROTATE_CCW); > } > }); > btn = objOnView.getCWbutton(); > btn.setTag(objOnView); > > btn.setOnClickListener(new OnClickListener() { > @Override > public void onClick(View v) { > ImageButton ibtn = (ImageButton)v; > imgFile ii = (imgFile)ibtn.getTag(); > ii.rotateThumbnail(imgFile.ROTATE_CW); > } > }); > // Schedule the image to be loaded in the background > objOnView.scaleAndRotateImage( true ); > } catch( Exception ex ) { > Log.e( TAG, ex.getMessage() ); > } > return vi; > } > } > > I hope this helps... > > Regards, > Simon > > > On 27/07/2011 1:20 PM, feiyangfeixue feiyangfeixue wrote: > > Some day ago, the same problem occures to me. The reason is that the > ListView is design to reuse the ListItem, which means that the Item #9 and > #17 reuse items #0-#8. So you should find some to maintain the View status > ( such as checkbox check status ) in some data structure. For example ,you > can forge a list to mark every checkbox status. In the getView method ,when > you get Checkbox view, you should set the check status by yourself. > Hopelly that can help you. > > 2011/7/26 Viral Brahmbhatt <[email protected]> > >> Hi there, >> >> I am trying to implement a listview with image, text and checkbox within >> it, using baseadapter. >> >> >> the problem is, let's say i have 20 items in list, so when i select the >> first item checkbox, and scroll down the list, i can see the item #9 and #17 >> also get checked automatically. >> >> can anyone pls help me to understand what is it doing? >> >> -- >> *Regards, >> Viral* >> -- >> You received this message because you are subscribed to the Google >> Groups "Android Developers" group. >> To post to this group, send email to [email protected] >> To unsubscribe from this group, send email to >> [email protected] >> For more options, visit this group at >> http://groups.google.com/group/android-developers?hl=en > > > -- > You received this message because you are subscribed to the Google > Groups "Android Developers" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/android-developers?hl=en > > > -- > You received this message because you are subscribed to the Google > Groups "Android Developers" group. > To post to this group, send email to [email protected] > To unsubscribe from this group, send email to > [email protected] > For more options, visit this group at > http://groups.google.com/group/android-developers?hl=en > -- *Regards, Viral* -- You received this message because you are subscribed to the Google Groups "Android Developers" group. 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