title: How to do validation in EditText within a ListView?
body: <p>I have problem in validating Edittext in listview in onFocusChangeListner.</p>
  
  <p>My UI looks like this</p>
  
  <pre><code>MeterName Previous CurrentReading
  Meter1    100      Here i want to type current reading
  </code></pre>
  
  <p>When I type the current Reading it will compare with previous reading. Current Reading can't be less than Previous. If it is less than previous then I want to alert the user and  focus is on same EditBox.</p>
  
  <p>My code is here:</p>
  
  <pre><code> public void onFocusChange(View v, boolean hasFocus) {
  
            try {
              Previous_Reading = getArray_Meter_Reading.getJSONObject(holder.ref)
                          .getString("PrevMeterReading").toString();
              Cumulative = getArray_Meter_Reading
                      .getJSONObject(holder.ref).getString("Cumulative")
                      .toString();
          } catch (JSONException e) {
              // TODO Auto-generated catch block
              e.printStackTrace();
          }
  
  
  
             if(!hasFocus){
  
                 int Current=Integer.valueOf(holder.adp_Current.getText().toString());
                 Previous=Integer.parseInt(Previous_Reading);
                  if(Current&lt;  Previous ){
                      AlertDialog.Builder builder = new AlertDialog.Builder(
                              context);
                      builder.setTitle("WARNING");
                      builder.setIcon(android.R.drawable.ic_dialog_alert);
                      builder.setMessage("Please Enter UserName");
                      builder.setPositiveButton("ok",
                              new DialogInterface.OnClickListener() {
  
                                  public void onClick(DialogInterface dialog,
                                          int which) {
  
                                      // Caption.requestFocus();
  
                                  }
                              });
  
                      AlertDialog diag = builder.create();
                      diag.show();
                  }
  
             }
  
        } });
  </code></pre>
  
  <p>With this code, when I start typing in EditBox alert is shown for all the characters, what I type like if previous is 600 and I type current reading like 6 it shows me alertdialog then
  5 again alertdialog till it is greater than previous value. </p>
  
  <p>When I click on EditText hasFocus is true and when I type any number say 5 focus changes to false.</p>
  
  <p>Can any one tell me how to do validation for that by giving sample code?</p>