Python Tutorial

Friday, January 14, 2011

Android button/Android button action

UI design in android is very faster using xml

Here i am using linearLayout.
From this example we will know how to create a button and then give this button action.Lets see

Xml file description:
     At first i declared here a textview wich will changed after button action performed.
Each elements need a ID, for example textview id is myTextViev. we also define each content layout size and position (AbsoluteLayout).
Then i declared a button (id=myButton,name=Submit) and set button width height


Now you need to create a file named 'my_button_interface.xml' then paste the code below

//my_button_interface.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" > <TextView android:id="@+id/myTextViev" android:layout_width="wrap_content" android:layout_height="wrap_content" /> <Button android:id="@+id/myButton" android:layout_width="100px" android:layout_height="50px" android:text="Submit" /> </LinearLayout>

Code description:

First you need to set layout using setContentView(R.layout.my_button_interface).Now you get all elements of this layout.
If we want to get declare text view code is tv = (TextView) findViewById(R.id.myTextViev),now you
can set text in this textview.
For button action you need to implements OnClickListener,then everything is easy....

//AndroidButton.java

import android.app.Activity; import android.os.Bundle; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.TextView; public class AndroidButton extends Activity implements OnClickListener { /** Called when the activity is first created. */ Button btn; TextView tv; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.my_button_interface); btn = (Button) findViewById(R.id.myButton); tv = (TextView) findViewById(R.id.myTextViev); tv.setText("This is old text"); btn.setOnClickListener(this); } @Override public void onClick(View v) { // TODO Auto-generated method stub if (v.getId() == R.id.myButton) { tv.setText("This is new text"); } } }
output:


Before click button


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After click button


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3 comments:

  1. Really very helpful post for beginners and good example for beginners. Thanks a lot.

    ReplyDelete