Pass Data From Activity To Dialog

Question

I am looking for a way to pass data from an activity onto a dialog box. I am trying to call showDialog(int);, however i don't see a way to pass any data to the dialog box. I need to pass a string to the dialog box in order to display a confirmation :)

Cheers

Answer 1

When you are doing showDialog(int) the Activity's onCreateDialog method is called. There you must create a dialog instance and return it, and it will be shown.

Then you are creating a dialog, you have a full access to your class' fields and can use values of them to adjust parameters and content of created dialog.

Answer 2

If you are targeting Android 2.2 (API Level 8 or higher) you can use

 public final boolean showDialog (int id, Bundle args)

And pass your arguments in Bundle. See documentation.

If you want to support older Android versions, you should save your arguments in Activity class members and then access them from your onPrepareDialog function. Note that onCreateDialog won't fit your needs as it's called only once for dialog creation.

class MyActivity {

    private static int MY_DLG = 1;
    private String m_dlgMsg;

    private showMyDialog(String msg){
        m_dlgMsg = msg;
        showDialog(MY_DLG);
    }

    private doSomething() {
        ...
        showMyDlg("some text");
    }

    protected void onCreateDialog(int id){
        if(id == MY_DLG){
            AlertDialog.Builder builder = new AlertDialog.Builder(this); 
            ....
            return builder.create();
         }
         return super.onCreateDialog(id);
    }        

    @Override
    protected void onPrepareDialog (int id, Dialog dialog){ 
         if(id == MY_DLG){ 
            AlertDialog adlg = (AlertDialog)dialog;
            adlg.setMessage(m_dlgMsg);
         } else {
            super.onPrepareDialog(id, dialog);
         }             
    }
}