CursorAdapter allows you to auto-update images

Question

I have a custom SimpleCursorAdapter that receives information from a database. If one value is 1, I am the background color of the ImageView, if it is 0, I do not color it. When the ListView is loaded, everything is correct, but then if I scroll through the items in the list, you will get the wrong image.

============= Just loaded ============= After scrolling up and down ====

I know about the processing of ListView and that when one item goes off the screen, its resources are freed up, but I don’t understand why, when they return to the screen, they are loaded incorrectly. I got it by simply setting the ImageView color to transparent when I don't want it to be colored: is this a workaround - the only way to make it work correctly?

This is my corresponding code:

RecipeCursorAdapter.java

public class RecipeCursorAdaptor extends SimpleCursorAdapter { private final Context mContext; private final int mLayout; private final Cursor mCursor; private final LayoutInflater mLayoutInflater; public CustomCursorAdaptor(Context context, int layout, Cursor c, String[] from, int[] to) { super(context, layout, c, from, to); this.mLayout = layout; this.mContext = context; this.mCursor = c; this.mLayoutInflater = LayoutInflater.from(mContext); } private final class ViewHolder { TextView txt_title; TextView txt_time; TextView txt_difficulty; ImageView img_color; } public View getView(int position, View convertView, ViewGroup parent) { if (mCursor.moveToPosition(position)) { ViewHolder viewHolder; if (convertView == null) { convertView = mLayoutInflater.inflate(mLayout, null); viewHolder = new ViewHolder(); viewHolder.img_color = (ImageView) convertView.findViewById(R.id.ricettaColore); viewHolder.txt_title = (TextView) convertView.findViewById(R.id.ricettaTitolo); viewHolder.txt_time = (TextView) convertView.findViewById(R.id.ricettaTempo); viewHolder.txt_difficulty = (TextView) convertView.findViewById(R.id.ricettaDifficolta); convertView.setTag(viewHolder); } else { viewHolder = (ViewHolder) convertView.getTag(); } String title = mCursor.getString(1); String time = mCursor.getString(2); String difficulty = mCursor.getString(3); int vegetarian = mCursor.getInt(4); viewHolder.txt_title.setText(title); viewHolder.txt_time.setText(time); viewHolder.txt_difficulty.setText(difficulty); if(vegetarian == 1) viewHolder.img_color.setBackgroundColor(0xff669900); /* Adding these two lines it works properly else viewHolder.img_color.setBackgroundColor(0x00000000); */ } return convertView; } 

list_ricette.xml

 <?xml version="1.0" encoding="utf-8"?> 

 <ImageView android:id="@+id/ricettaColore" android:layout_width="5dip" android:layout_height="45dip" android:layout_alignParentLeft="true" android:layout_centerVertical="true" android:contentDescription="Ricetta vegetariana" /> <TextView android:id="@+id/ricettaTitolo" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_marginLeft="5dip" android:layout_toRightOf="@+id/ricettaColore" android:scrollHorizontally="false" android:singleLine="true" android:text="Titolo Ricetta" android:textAppearance="?android:attr/textAppearanceMedium" /> <TextView android:id="@+id/ricettaDifficolta" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_alignLeft="@+id/ricettaTitolo" android:layout_below="@+id/ricettaTitolo" android:scrollHorizontally="false" android:singleLine="true" android:text="Difficoltà" android:textAppearance="?android:attr/textAppearanceSmall" android:textColor="#A1A1A1" /> <TextView android:id="@+id/ricettaTempo" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_alignBottom="@+id/ricettaDifficolta" android:layout_alignParentRight="true" android:layout_below="@+id/ricettaTitolo" android:gravity="right" android:text="Tempo" android:textAppearance="?android:attr/textAppearanceSmall" android:textColor="#A1A1A1" /> 

Answer 1

You want to make your ViewHolder class static and create a static int array inside this view holder class. In getView, you must install this array with your value from the database, and use this array to set the string as you want.

Here's how I managed to set checkboxes correctly in ExpandableListView:

 static class ViewHolder { CheckBox check; static boolean[][] bool = new boolean[parentCounter][childCounter]; public static void setChecked(int parent, int child, boolean value) { bool[parent][child] = value; } public static boolean getChecked(int parent, int child) { return bool[parent][child]; } } 

This is the same concept.