[解決済み】ダイアログにテキストボックスを作成する方法

質問

パスワード入力用のエディットテキストボックスをダイアログボックスに作成しようとしています。 を作ろうとしているのですが、うまくいきません。私は初心者です。 どうか私を助けてください。

public class MainActivity extends Activity {

Button create, show, setting;
//String pass="admin";String password;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    create = (Button)findViewById(R.id.amcreate);
    setting = (Button)findViewById(R.id.amsetting);
    show = (Button)findViewById(R.id.amshow);
    //input = (EditText)findViewById(R.id.this);

    setting.setVisibility(View.INVISIBLE);

    create.setOnClickListener(new View.OnClickListener() {
        public void onClick(View view) {
            Intent myIntent1 = new Intent(view.getContext(), Create.class);
            startActivityForResult(myIntent1, 0);
        }

    });

    show.setOnClickListener(new View.OnClickListener() {
        //@SuppressWarnings("deprecation")
        public void onClick(final View view) {

            // Creating alert Dialog with one Button
            AlertDialog.Builder alertDialog = new AlertDialog.Builder(MainActivity.this);

            //AlertDialog alertDialog = new AlertDialog.Builder(MainActivity.this).create();

            // Setting Dialog Title
            alertDialog.setTitle("PASSWORD");

            // Setting Dialog Message
            alertDialog.setMessage("Enter Password");
            **final EditText input = new EditText(this);**
            //alertDialog.setView(input);

            // Setting Icon to Dialog
            alertDialog.setIcon(R.drawable.key);

            // Setting Positive "Yes" Button
            alertDialog.setPositiveButton("YES",
                    new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog,int which) {
                            // Write your code here to execute after dialog
                            Toast.makeText(getApplicationContext(),"Password Matched", Toast.LENGTH_SHORT).show();
                            Intent myIntent1 = new Intent(view.getContext(), Show.class);
                            startActivityForResult(myIntent1, 0);
                        }
                    });
            // Setting Negative "NO" Button
            alertDialog.setNegativeButton("NO",
                    new DialogInterface.OnClickListener() {
                        public void onClick(DialogInterface dialog, int which) {
                            // Write your code here to execute after dialog
                            dialog.cancel();
                        }
                    });

            // closed

            // Showing Alert Message
            alertDialog.show();
        }

    }); 

画像

として取得したい。

 AlertDialog.Builder alertDialog = new AlertDialog.Builder(MainActivity.this);
 alertDialog.setTitle("PASSWORD");
 alertDialog.setMessage("Enter Password");

 final EditText input = new EditText(MainActivity.this);
 LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
     LinearLayout.LayoutParams.MATCH_PARENT,
     LinearLayout.LayoutParams.MATCH_PARENT);
 input.setLayoutParams(lp);
 alertDialog.setView(input);
 alertDialog.setIcon(R.drawable.key);

 alertDialog.setPositiveButton("YES",
     new DialogInterface.OnClickListener() {
         public void onClick(DialogInterface dialog, int which) {
             password = input.getText().toString();
             if (password.compareTo("") == 0) {
                 if (pass.equals(password)) {
                     Toast.makeText(getApplicationContext(),
                         "Password Matched", Toast.LENGTH_SHORT).show();
                     Intent myIntent1 = new Intent(view.getContext(),
                         Show.class);
                     startActivityForResult(myIntent1, 0);
                 } else {
                     Toast.makeText(getApplicationContext(),
                         "Wrong Password!", Toast.LENGTH_SHORT).show();
                 }
             }
         }
     });

 alertDialog.setNegativeButton("NO",
     new DialogInterface.OnClickListener() {
         public void onClick(DialogInterface dialog, int which) {
             dialog.cancel();
         }
     });

 alertDialog.show();
 }

 });

解決方法は？

アクティビティコンテキストを使用する

これを置き換える

  final EditText input = new EditText(this);

で

  final EditText input = new EditText(MainActivity.this);  
  LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(
                        LinearLayout.LayoutParams.MATCH_PARENT,
                        LinearLayout.LayoutParams.MATCH_PARENT);
  input.setLayoutParams(lp);
  alertDialog.setView(input); // uncomment this line