Adding a button for Android in Java code

Question

Is it possible to add a button to an Activity layout with Java code. If this is possible, how? This is my current layout file:

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/ad_catalog_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/background"
android:orientation="vertical" >

<com.google.ads.AdView
    xmlns:googleads="http://schemas.android.com/apk/lib/com.google.ads"
    android:id="@+id/ad"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    googleads:adSize="IAB_BANNER"
    googleads:adUnitId="a14d7f7d2180609" />

<TextView
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="@string/menu_mods"
    android:textColor="#FFFFFF"
    android:textSize="25sp" />

<ScrollView
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_margin="2dp" >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical" >

        <Button
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:onClick="enterPeacefulPack"
            android:text="@string/peacefulpack"
            android:paddingBottom="20dp"
            android:paddingLeft="20dp"
            android:paddingRight="20dp"
            android:paddingTop="20dp"
            android:textColor="#FFFFFF"
            android:textSize="25sp" />
    </LinearLayout>
</ScrollView>

If it is possible I would like to have the Java-added button inside the LinearLayout that is inside of the ScrollView, but if that isn't possible it would also be possible to get it in the normal LinearLayout.

The reason why I want to be able to get buttons through Java is that I have an Array that contains several objects. For every object I would like to have a button. This Array will increase in size over time.

This is the Activity file I'm using

package com.wuppy.minecraftmods.mods;

import android.annotation.SuppressLint;
import android.app.ActionBar.LayoutParams;
import android.app.Activity;
import android.content.Intent;
import android.os.Build;
import android.os.Bundle;
import android.support.v4.app.NavUtils;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;

import com.google.ads.AdRequest;
import com.google.ads.AdView;
import com.wuppy.minecraftmods.R;

public class Mods extends Activity
{
@SuppressLint("NewApi")
@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_mods);

    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB)
    {
        getActionBar().setDisplayHomeAsUpEnabled(true);
    }

    AdView adView = (AdView) this.findViewById(R.id.ad);
    adView.loadAd(new AdRequest());
}

@Override
public boolean onOptionsItemSelected(MenuItem item)
{
    switch (item.getItemId())
    {
    case android.R.id.home:
        NavUtils.navigateUpFromSameTask(this);
        return true;
    }
    return super.onOptionsItemSelected(item);
}

public void enterPeacefulPack(View view)
{
    Intent intent = new Intent(this, ModPeacefulpack.class);
    startActivity(intent);
}
}

So I want to add buttons through Java since I can't really do this in xml. Is that possible and if so how?

please refer this url. http://stackoverflow.com/questions/4907609/add-button-to-a-layout-programmatically — jigspatel, Apr 01 '13 at 10:18
It's perfectly possible and there are lots of posts on this topic in the Internet. Why won't you use Google? — Egor, Apr 01 '13 at 10:18

score 5 · Answer 1 · answered Apr 01 '13 at 10:19

5

Yes it possible, define an id to your LinearLayout in your XML file. lets say:

android:id="@+id/buttonContainer"

Then in the Activity java code find this id after setting the contentView:

LinearLayout buttonContainer = (LinearLayout) findViewById(R.id.buttonContainer);

Then create your button:

Button button = new Button();

customize it as you like, given the methods provided.

And finally add it to your layout:

buttonContainer.addView(button);

answered Apr 01 '13 at 10:19

Emil Adz

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2

No matter what I do, `Button button = new Button();` does not work without inputting a context. It works if you are importing the widget from `java.awt` as opposed to android.widget. But unless I use `(this)` as the context, new Button() does not work in java. Can you please explain why you show just button(); ? Thanks. – dbconfession Sep 15 '14 at 23:46
1

@dbconfession it's a mistake, Android views require a context. – Lesleh Feb 21 '15 at 05:46

score 1 · Answer 2 · answered Apr 01 '13 at 10:24

Add the appropriate import to your Activity:

import android.widget.Button;

Then create a new button object within the onCreate method:

Button myButton = new Button(this);
myButton.setText("Press Me");

Finally add the button to the layout:

LinearLayout layout = (LinearLayout) findViewById(R.id.layout1);
layout.addView(myButton);

Anas Imran Tasadduq · Answer 3 · 2015-05-27T10:04:56.653

This link gives a full tutorial on how to add widgets to your Android app using java code. So, here's a summary for your button thing:

1) You remove the setContentView(...) line from the onCreate() method

2) You define your button like this: Button myButton = new Button(this);

3) You define a layout like this: RelativeLayout myLayout = new RelativeLayout(this);

4) You add the button to the layout like this: myLayout.addView(myButton);

5) You set the layout like this: setContentView(myLayout);

To add a button to a layout that is already defined by the .xml file, which is in your case, you write the following code instead of the above five steps:

LinearLayout layout = (LinearLayout) findViewById(R.id.myLayout);
Button button = new Button(this);
layout.addView(button);

Adding a button for Android in Java code

3 Answers3

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