getting null pointer exception inside custom dialogBox

Question

Hey I am creating a custom dialog box containing 2 editText. I don't know what is wrong with this code but whenever the user click on submit it say null values inside the editText.

Can anyone help on this ?

Below is the code for custom dialogBox

private void showPriceDialog() {
        final AlertDialog.Builder builder = new AlertDialog.Builder(this);
        final View dialogView = LayoutInflater.from(this).inflate(R.layout.content_price_filter,null);
       //Button submitBtn = (Button)findViewById(R.id.submitBtn);

        builder.setView(dialogView);
        final android.support.design.widget.TextInputEditText minPrice = (android.support.design.widget.TextInputEditText)findViewById(R.id.minPrice);
        final android.support.design.widget.TextInputEditText maxPrice = (android.support.design.widget.TextInputEditText)findViewById(R.id.maxPrice);

        builder.setTitle("Set Price");
        builder.setPositiveButton("Submit", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {


                String max = maxPrice.getText().toString();
                String min = minPrice.getText().toString();
                if (max.equals("") || min.equals("")){
                    Toast.makeText(getApplicationContext(),"empty fields",Toast.LENGTH_SHORT).show();
                    return;
                }
                mPriceValueTxt.setText(max + " Rs min :"+ min);
            }
        });
        builder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                     dialog.dismiss();
            }
        });
        AlertDialog al = builder.create();
        al.show();
}

Below is the layout of the custom dialog Layout

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent">


    <android.support.design.widget.TextInputLayout
        android:id="@+id/minPriceSelector"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:ems="10"
        android:inputType="text"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:layout_constraintRight_toLeftOf="@+id/maxPriceSelector"
        android:layout_marginRight="8dp"
        android:layout_marginLeft="8dp">

        <android.support.design.widget.TextInputEditText
            android:id="@+id/minPrice"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:hint="Min Price"
            android:inputType="number"
            android:singleLine="true" />

    </android.support.design.widget.TextInputLayout>

    <android.support.design.widget.TextInputLayout
        android:id="@+id/maxPriceSelector"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:ems="10"
        android:inputType="text"
        app:layout_constraintLeft_toRightOf="@+id/minPriceSelector"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        android:layout_marginLeft="8dp"
        android:layout_marginRight="8dp">

        <android.support.design.widget.TextInputEditText
            android:id="@+id/maxPrice"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:hint="Max Price"
            android:inputType="number"
            android:singleLine="true" />

    </android.support.design.widget.TextInputLayout>
</android.support.constraint.ConstraintLayout>

This is the error i am getting while clicking submit

09-03 13:11:30.180 22652-22652/com.example.ashis.propertysearch E/AndroidRuntime: FATAL EXCEPTION: main
                                                                                  Process: com.example.ashis.propertysearch, PID: 22652
                                                                                  java.lang.NullPointerException: Attempt to invoke virtual method 'android.text.Editable android.support.design.widget.TextInputEditText.getText()' on a null object reference
                                                                                      at com.example.ashis.propertysearch.FiltersActivity$1.onClick(FiltersActivity.java:290)
                                                                                      at android.support.v7.app.AlertController$ButtonHandler.handleMessage(AlertController.java:161)
                                                                                      at android.os.Handler.dispatchMessage(Handler.java:102)
                                                                                      at android.os.Looper.loop(Looper.java:154)
                                                                                      at android.app.ActivityThread.main(ActivityThread.java:6204)
                                                                                      at java.lang.reflect.Method.invoke(Native Method)
                                                                                      at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:891)
                                                                                      at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:781)

Answer 1

you have to do like below.

builder.setView(dialogView);
        final android.support.design.widget.TextInputEditText minPrice = (android.support.design.widget.TextInputEditText) dialogView.findViewById(R.id.minPrice);
        final android.support.design.widget.TextInputEditText maxPrice = (android.support.design.widget.TextInputEditText) dialogView.findViewById(R.id.maxPrice);