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android - Trying to override getView in a SimpleCursorAdapter gives NullPointerExceptio

Would very much appreciate any help or hint on were to go next.

I'm trying to change the content of a row in ListView programmatically. In one row there are 3 TextView and a ProgressBar. I want to animate the ProgressBar if the 'result' column of the current row is zero.

After reading some tutorials and docs, I came to the conclusion that LayoutInflater has to be used and getView() - overriden. Maybe I am wrong on this.

If I return row = inflater.inflate(R.layout.row, null); from the function, it gives NullPointerException.

Here is the code:

    private final class mySimpleCursorAdapter extends SimpleCursorAdapter {

    private Cursor localCursor;
    private Context localContext;

    public mySimpleCursorAdapter(Context context, int layout, Cursor c, String[] from, int[] to) {
        super(context, layout, c, from, to);            
        this.localCursor = c;
        this.localContext = context;

    }

    /**
     *    1. ListView asks adapter "give me a view" (getView) for each item of the list
     *    2. A new View is returned and displayed
     */
    public View getView(int position, View  convertView, ViewGroup  parent) {
        View row = super.getView(position, convertView, parent);

        LayoutInflater inflater = (LayoutInflater)localContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

        String result = localCursor.getString(2);
        int resInt = Integer.parseInt(result);

        Log.d(TAG, "row " + row);

        // if 'result' column form the TABLE is 0, do something useful:
        if(resInt == 0) {           
            ProgressBar progress = (ProgressBar) row.findViewById(R.id.update_progress);
            progress.setIndeterminate(true);

            TextView edit1 = (TextView)row.findViewById(R.id.row_id);
            TextView edit2 = (TextView)row.findViewById(R.id.request);
            TextView edit3 = (TextView)row.findViewById(R.id.result);
            edit1.setText("1");
            edit2.setText("2");
            edit3.setText("3");
            row = inflater.inflate(R.layout.row, null);             
        }

        return row;
    }

here is the Stack Trace:

03-08 03:15:29.639: ERROR/AndroidRuntime(619): java.lang.NullPointerException
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.SimpleCursorAdapter.bindView(SimpleCursorAdapter.java:149)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.CursorAdapter.getView(CursorAdapter.java:186)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at com.dhristov.test1.test1$mySimpleCursorAdapter.getView(test1.java:105)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.AbsListView.obtainView(AbsListView.java:1256)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.ListView.makeAndAddView(ListView.java:1668)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.ListView.fillDown(ListView.java:637)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.ListView.fillSpecific(ListView.java:1224)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.ListView.layoutChildren(ListView.java:1499)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.AbsListView.onLayout(AbsListView.java:1113)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.view.View.layout(View.java:6830)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1119)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.LinearLayout.layoutVertical(LinearLayout.java:998)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.LinearLayout.onLayout(LinearLayout.java:918)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.view.View.layout(View.java:6830)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1119)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.LinearLayout.layoutVertical(LinearLayout.java:998)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.LinearLayout.onLayout(LinearLayout.java:918)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.view.View.layout(View.java:6830)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.FrameLayout.onLayout(FrameLayout.java:333)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.view.View.layout(View.java:6830)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.LinearLayout.setChildFrame(LinearLayout.java:1119)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.LinearLayout.layoutVertical(LinearLayout.java:998)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.LinearLayout.onLayout(LinearLayout.java:918)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.view.View.layout(View.java:6830)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.widget.FrameLayout.onLayout(FrameLayout.java:333)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.view.View.layout(View.java:6830)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.view.ViewRoot.performTraversals(ViewRoot.java:996)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.view.ViewRoot.handleMessage(ViewRoot.java:1633)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.os.Handler.dispatchMessage(Handler.java:99)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.os.Looper.loop(Looper.java:123)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at android.app.ActivityThread.main(ActivityThread.java:4363)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at java.lang.reflect.Method.invokeNative(Native Method)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at java.lang.reflect.Method.invoke(Method.java:521)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
03-08 03:15:29.639: ERROR/AndroidRuntime(619):     at dalvik.system.NativeStart.main(Native Method)
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1 Answer

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by (71.8m points)

For CursorAdapter and subclasses, you should override newView() and bindView() instead of getView().

More importantly, though, you should not get calling super.getView(). That is where you are crashing.


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