Introduction
This article explains how to dynamically create the layout in Android. Android Studio is used for the sample.
Typically we develp the layout for an Android application by creating the XML file. But in this we will create the layout for the activity using code in the class file. In this I have created four buttons inside a RelativeLayout that uses methods and variables to change their layout. First you will create the Relativelayout and call LayoutParams to set the parameters as in the following:
// Creating a new RelativeLayout
RelativeLayout relativeLayout = new RelativeLayout(this);
// Defining the RelativeLayout layout parameters with Fill_Parent
RelativeLayout.LayoutParams relativeLayoutParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.FILL_PARENT, RelativeLayout.LayoutParams.FILL_PARENT);
Now you will create the buttons that you want to show on screens as in the following:
// Creating a new Left Button
Button button1 = new Button(this);
button1.setText("Button1");
// Creating a new Left Button with Margin
Button button2 = new Button(this);
button2.setText("Button2");
// Creating a new Center Button
Button button3 = new Button(this);
button3.setText("Button3");
// Creating a new Bottom Button
Button button4 = new Button(this);
button4.setText("Button4");
Step 1
Create a project as in the following:
Step 2
Default XML file
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
tools:context=".MainActivity">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/hello_world" />
</RelativeLayout>
Step 3
Create a Java file and provide this in it:
package com.dynamicbuttoncreation;
import android.app.Activity;
import android.os.Bundle;
import android.widget.Button;
import android.widget.RelativeLayout;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
import android.graphics.Color;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.Button;
import android.widget.RelativeLayout;
public class MainActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Creating a new RelativeLayout
RelativeLayout relativeLayout = new RelativeLayout(this);
// Defining the RelativeLayout layout parameters with Fill_Parent
RelativeLayout.LayoutParams relativeLayoutParams = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.FILL_PARENT, RelativeLayout.LayoutParams.FILL_PARENT);
// Creating a new Left Button
Button button1 = new Button(this);
button1.setText("Button1");
// Creating a new Left Button with Margin
Button button2 = new Button(this);
button2.setText("Button2");
// Creating a new Center Button
Button button3 = new Button(this);
button3.setText("Button3");
// Creating a new Bottom Button
Button button4 = new Button(this);
button4.setText("Button4");
// Add a Layout to the Buttons
AddButtonLayout(button1, RelativeLayout.ALIGN_PARENT_LEFT);
AddButtonLayout(button3, RelativeLayout.CENTER_IN_PARENT);
AddButtonLayout(button4, RelativeLayout.ALIGN_PARENT_BOTTOM);
// Add a Layout to the Button with Margin
LayoutAddButton(button2, RelativeLayout.ALIGN_PARENT_LEFT, 30, 80, 0, 0);
// Add the Buttons to the View
relativeLayout.addView(button1);
relativeLayout.addView(button3);
relativeLayout.addView(button4);
relativeLayout.addView(button2);
// Setting the RelativeLayout as our content view
setContentView(relativeLayout, relativeLayoutParams);
}
private void LayoutAddButton(Button button, int centerInParent, int marginLeft, int marginTop, int marginRight, int marginBottom) {
// Defining the layout parameters of the Button
RelativeLayout.LayoutParams buttonLayoutParameters = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
// Add Margin to the LayoutParameters
buttonLayoutParameters.setMargins(marginLeft, marginTop, marginRight, marginBottom);
// Add Rule to Layout
buttonLayoutParameters.addRule(centerInParent);
// Setting the parameters on the Button
button.setLayoutParams(buttonLayoutParameters);
}
private void AddButtonLayout(Button button, int centerInParent) {
// Just call the other AddButtonLayout Method with Margin 0
LayoutAddButton(button, centerInParent, 0, 0, 0, 0);
}
}
Step 4
Android Manifest.xml file
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.dynamicbuttoncreation"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="7"
android:targetSdkVersion="16" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.dynamicbuttoncreation.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
Step 5
Output