Create a simple Layout

[Alex Garci]

Hi,

I'm newbie in Android and I can't create a simple LinearLayout. I have the following code in several files:

Principal.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
    
    <TextView 
	    android:text="Nombre"
	    />
    
    <EditText 
        android:width="100px"
        />
	
</LinearLayout>

strings.xml

<resources>

    <string name="app_name">Interfaces</string>
    <string name="hello_world">Hello world!</string>
    <string name="menu_settings">Settings</string>
    <string name="title_activity_layout">LayoutActivity</string>
	<string name="Nombre">Nombre</string>
</resources>

LayoutActivity.java

package example.interfaces;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;

public class LayoutActivity extends Activity {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.principal); //error
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.principal, menu); //error
        return true;
    }
}

Errors are in the last file, when I try to change the main activity's name. I have errors in lines setContentView and getMenuInflater. The error is:

principal cannot be resolved or is not a field.

I save principal.xml file in res/layout and string.xml in res/values folder. LayoutActivity.java is in src/example.interfaces folder.

How can I fix this error?

I'm working with Eclipse and API Level 16.

Thanks.

[Muhammad Saifuddin]

Errors are in the last file, when I try to change the main activity's name. I have errors in lines setContentView and getMenuInflater. The error is:
principal cannot be resolved or is not a field.

why you changing the activity name? it won't compile until you fix the the same name for your file.

Java Rules:
The filename must match exactly the name of your class.

https://coderanch.com/how-to/java/Java-FAQ