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in Technique[技术] by (71.8m points)

Android getText from EditText return NULL

in this simple Application of my first program in Android i want to get username and password from User. but after click on button that return NULL and thats incorrect, username and password fields have string and are not NULL. Textusername and Textpassword in this code are NULL and can not get string from R.id.username AND R.id.password

My XML:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="fill_parent"
              android:layout_height="fill_parent"
        >
    <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:orientation="horizontal"
            >

        <TextView
                android:layout_width="0dp"
                android:layout_height="40dp"
                android:layout_weight="1"
                android:text="@string/EnterUsername"
                />
        <EditText
                android:layout_width="0dp"
                android:layout_height="40dp"
                android:layout_weight="1"
                android:id="@+id/username"
                />
    </LinearLayout>
    <LinearLayout
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:orientation="horizontal"
            >

        <TextView
                android:layout_width="0dp"
                android:layout_height="40dp"
                android:layout_weight="1"
                android:text="@string/EnterPassword"
                />
        <EditText
                android:layout_width="0dp"
                android:layout_height="40dp"
                android:layout_weight="1"
                android:id="@+id/password"
                />
    </LinearLayout>
    <TextView
            android:layout_width="fill_parent"
            android:layout_height="0dp"
            android:layout_weight="1"
            />
    <Button
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:id="@+id/submitButton"
            android:text="@string/SubmitButton"
            android:gravity="center"
            android:background="@drawable/purple"/>
</LinearLayout>

My Code:

package com.example.AndroidMultiPage;

import android.app.Activity;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;

public class MyActivity extends Activity {
    /**
     * Called when the activity is first created.
     */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        final EditText username = (EditText) findViewById(R.id.username);
        final EditText password = (EditText) findViewById(R.id.password);

        Button   submit   = (Button)   findViewById(R.id.submitButton);

        final String Textusername = username.getText().toString();
        final String Textpassword = password.getText().toString();

        submit.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Toast.makeText(
                         MyActivity.this, Textusername, 
                         Toast.LENGTH_SHORT).show();

                //TOAST SHOW NULL
            }
        });
    }
}
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1 Answer

0 votes
by (71.8m points)

You should move

 final String Textusername = username.getText().toString();
 final String Textpassword = password.getText().toString();

under onClick(..) of submit Button and inside onClick(..) you should check String values are NULL or not. as @Raghunandan said...


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