Closing Application with Exit button [duplicate]

This question already has answers here: 开发者_如何学JAVA How to exit from the application and show the home screen? (22 answers) Closed 3 years ago.

I'm a beginner in android, I'm practicing a Project that have a 2 labels and 1 exit button. But when I run this project in android phone the exit button is not working, it won't exit at all.

How can I make exit button work?

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Below used main.xml file

 <?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">
<TextView android:layout_width="fill_parent"
    android:layout_height="wrap_content" android:id="@+id/txt1" android:text="txt1" />
<TextView android:layout_width="fill_parent"
    android:layout_height="wrap_content" android:id="@+id/txt2"   android:text="txt2"/>
<Button android:layout_width="fill_parent"
    android:layout_height="wrap_content" android:id="@+id/btn1"
    android:text="Close App" />
  </LinearLayout>

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and text.java file is below

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import android.app.Activity;

import android.os.Bundle;

import android.view.View;

import android.view.View.OnClickListener;

import android.widget.Button;

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

    Button btn1 = (Button) findViewById(R.id.btn1);
    btn1.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
            finish();
            System.exit(0);
        }
    });
    }
 }

---

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Don't ever put an Exit button on an Android app. Let the OS decide when to kill your Activity. Learn about the Android Activity lifecycle and implement any necessary callbacks.

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try this for close app

Activity.finish();
System.exit(0);

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i try this

Button btnexit = (Button)findviewbyId(btn_exit);

btnexit.setOnClicklistenr(new onClicklister(){

     @override
     public void onClick(View v){
            finish();
});

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this.close_Button = (Button)this.findViewById(R.id.close);
   this.close_Button.setOnClickListener(new OnClickListener() {
     @Override
     public void onClick(View v) {
        finish();
     }
  });

finish() - Call this when your activity is done and should be closed. The ActivityResult is propagated back to whoever launched you via onActivityResult().

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You cannot exit your application. Using android.finish() won't exit the application, it just kills the activity. It's used when we don't want to see the previous activity on back button click. The application automatically exits when you switch off the device. The Android architecture does not support exiting the app. If you want, you can forcefully exit the app, but that's not considered good practice.