- Create a simple example for Dynamic Binding
- Access Static Binding in Android
1.Create a simple example for Dynamic Binding.
Step 1 : Select File -> New -> Project -> Android Application Project (or) Android Project. Fill the forms and click "Finish" button. If you have any doubt regarding create a new project Click Here.
Step 2 : Open res -> layout -> activity_main.xml (or) main.xml and add following code :
<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" >
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="37dp"
android:text="Dynamic Binding" />
<TextView
android:id="@+id/textView1"
android:textSize="20dp"
android:gravity="center"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_marginTop="150dp" />
</RelativeLayout>
Step 3 : Open src -> package -> MainActivity.java and add following code
package com.gudivada.hemanthsomaraju;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class MainActivity extends Activity {
Button bind;
TextView tv;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
bind = (Button) findViewById(R.id.button1);
tv = (TextView) findViewById(R.id.textView1);
bind.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// TODO Auto-generated method stub
B obj = new B();
tv.setText(obj.display());
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
class A
{
protected String str_A = null;
String display()
{
str_A = "Base Class Function Called By Hemanth Somaraju";
return str_A;
}
}
class B extends A
{
String display()
{
if (str_A == null)
{
str_A = "Derived Class Function Called By Hemanth Somaraju";
}
return str_A;
}
}
Step 4 : Open AndroidManifest.xml and add following code :
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.gudivada.hemanthsomaraju"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="18" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.gudivada.hemanthsomaraju.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 : Our output will be like this :
Step 6 : Now rewrite the Code in class B:
class B extends A
{
String display()
{
super.display();
if (str_A == null)
{
str_A = "Derived Class Function Called By Hemanth Somaraju";
}
return str_A;
}
}
Step
7 : Now
our output will be like this :
2.Access Static Binding in Android.
Step 1 : Select File -> New -> Project -> Android Application Project (or) Android Project. Fill the forms and click "Finish" button. If you have any doubt regarding create a new project Click Here.
Step 2 : Open res -> layout -> activity_main.xml (or) main.xml and add following code :
2.Access Static Binding in Android.
Step 1 : Select File -> New -> Project -> Android Application Project (or) Android Project. Fill the forms and click "Finish" button. If you have any doubt regarding create a new project Click Here.
Step 2 : Open res -> layout -> activity_main.xml (or) main.xml and add following code :
<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" >
<TextView
android:id="@+id/textView1"
android:textSize="20dp"
android:textColor="#FF0000"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="40dp"
android:text="Static Binding" />
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/textView1"
android:layout_centerHorizontal="true"
android:layout_marginTop="45dp"
android:text="Bind" />
<TextView
android:id="@+id/textView2"
android:textSize="18dp"
android:textColor="#8A2BE2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/button1"
android:layout_centerHorizontal="true"
android:layout_marginTop="40dp"
android:text="int" />
<TextView
android:id="@+id/textView3"
android:textSize="18dp"
android:textColor="#FF1493"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/textView2"
android:layout_centerHorizontal="true"
android:layout_marginTop="40dp"
android:text="float" />
<TextView
android:id="@+id/textView4"
android:textSize="18dp"
android:textColor="#8B008B"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/textView3"
android:layout_centerHorizontal="true"
android:layout_marginTop="40dp"
android:text="Hemanth" />
</RelativeLayout>
Step 3 : Open src -> package -> MainActivity.java and add following code :
package com.gudivada.hemanthsomaraju;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class MainActivity extends Activity {
Button b;
TextView tv1, tv2, tv3;
String str1, str2, str3;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
b = (Button) findViewById(R.id.button1);
tv1 = (TextView) findViewById(R.id.textView2);
tv2 = (TextView) findViewById(R.id.textView3);
tv3 = (TextView) findViewById(R.id.textView4);
b.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
SubClass obj = new SubClass();
int val1 = obj.bind(23);
str1 = String.valueOf(val1);
tv1.setText(str1);
float val2 = obj.bind((float) 10.23);
str2 = String.valueOf(val2);
tv2.setText(str2);
str3 = obj.bind("Somaraju !!!");
tv3.setText(str3);
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
class SubClass {
int bind(int a) {
return a;
}
float bind(float a) {
return a;
}
String bind(String a) {
return a;
}
} Step 4 : Open AndroidManifest.xml and add following code :
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.gudivada.hemanthsomaraju"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="18" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.gudivada.hemanthsomaraju.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 : Our output will be like this :
