Java – I can’t create a default constructor from a class that extends dialogfragment, and I’ve created my own custom constructor

I'm confused about the error message about the default constructor

I have two classes mainactivity and resultdialog Some methods in mainactivity create a new dialog box and pass 2strings to the custom constructor in resultdialog

Resultdialog extends dialogfragment So I defined my own constructor, but when there was an error, I just created a parameterless constructor, but it is still not allowed to do so

I have searched for abit on so, but the answer is a little explanatory. Screen rotation may break and recreate the screen using the default constructor, but I still can't answer how to solve this problem

Someone please help me, I'm a little confused Part of my resultdialog class:

public class ResultDialog extends DialogFragment {

private String message;//to hold the message to be displayed
private String title;//for alert dialog title

//constructor for the dialog passing along message to be displayed in the alert dialog
public ResultDialog(String message,String title){
    this.message = message;
    this.title = title;

}

public ResultDialog(){
    //default constructor
}

Solution

You can use newinstance Check document

http://developer.android.com/reference/android/app/Fragment.html

And check it

Why do I want to avoid non-default constructors in fragments?

ResultDialog rd = ResultDialog.newInstance("message","title");

then

public static ResultDialog newInstance(String message,String title) {
    ResultDialog f = new ResultDialog();
    Bundle args = new Bundle();
    args.putString("message",message);
    args.putString("title",title);
    f.setArguments(args);
    return f;
}

And use getarguments () to retrieve the value

String message = getArguments().getString("message");
String title = getArguments().getString("title");

getArguments()

public final Bundle getArguments ()

Added in API level 11
Return the arguments supplied when the fragment was instantiated,if any.