Thursday, 3 April 2014

To provide animation to each radio button in a radioburron  group in android.

Here I am creating  RadioGroup Dynamicaly
int numAnswer=5;
RadioGroup radioGroupd=new RadioGroup(getApplicationContext());
                int numAnswer=Integer.valueOf(questions.get(showedNum).questions_answers_count);
                for(int i=0;i<numAnswer;i++)
                {
                    button=new  RadioButton(getApplicationContext());
                    button.setTextColor(Color.GREEN);
                    button.setId(i);
                    button.setTextSize(subtextSize);
                    button.setText(questions.get(showedNum).answer_list[i]);
                    radioGroupd.addView(button);
                }
             //imp  
                radioGroupd.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener()
                {
                    @Override
                    public void onCheckedChanged(RadioGroup group, int checkedId) {
                        // TODO Auto-generated method stub
/
                     int id=   group.getCheckedRadioButtonId();//get id
                        RadioButton b = (RadioButton) findViewById(id);
                                   b.startAnimation(myanimateItems);
                    }
                  
                });

How can I add Animation to RadioGroup in android

To provide animation to each radio button in a radioburron  group in android.

Here I am creating  RadioGroup Dynamicaly
int numAnswer=5;
RadioGroup radioGroupd=new RadioGroup(getApplicationContext());
                int numAnswer=Integer.valueOf(questions.get(showedNum).questions_answers_count);
                for(int i=0;i<numAnswer;i++)
                {
                    button=new  RadioButton(getApplicationContext());
                    button.setTextColor(Color.GREEN);
                    button.setId(i);
                    button.setTextSize(subtextSize);
                    button.setText(questions.get(showedNum).answer_list[i]);
                    radioGroupd.addView(button);
                }
             //imp  
                radioGroupd.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener()
                {
                    @Override
                    public void onCheckedChanged(RadioGroup group, int checkedId) {
                        // TODO Auto-generated method stub
/
                     int id=   group.getCheckedRadioButtonId();//get id
                        RadioButton b = (RadioButton) findViewById(id);
                                   b.startAnimation(myanimateItems);
                    }
                  
                });

Thursday, 3 January 2013

TimePicker View in Android

The TimePicker view enables users to select a time of the day, in either 24 Hour mode or AM/PM mode.For this you can use "android.widget.TimePicker" class in android.

You can create TimePicker View using <TimePicker> xml element like this -
 <TimePicker
        android:id="@+id/timePicker"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />
       

The TimePicker view displays a standard UI to enable user to set a time. By default, it displays time in the AM/PM format. If you want to change time in the 24 hour format, then you can use the setIs24HourView() method. There are two other important methods of TimePicker -
  • getCurrentHour()
  • getCurrentMinute()
Please note that getCurrentHour() method always returns the hour in 24-hour format i.e. value from 0 to 23.
   

activity_main.xml

(res/layout/activity_main.xml)


<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

      <TimePicker
        android:id="@+id/timePicker"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />
    
    <Button
        android:id="@+id/btn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="
Display Time" />
 </LinearLayout>
 

 
TimePickerDemoActivity
(File: TimePickerDemoActivity.java)

package com.example.timepickerdemosimple;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TimePicker;
import android.widget.Toast;

public class MainActivity extends Activity {
    /** Called when the activity is first created. */
   
    TimePicker timepicker;
   
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
       
        timepicker = (TimePicker) findViewById(R.id.timePicker);
        timepicker.setIs24HourView(true);
       
      
        // Button View
       Button button = (Button) findViewById(R.id.btn);
       button.setOnClickListener(new View.OnClickListener() {
       
     //   @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub
       
        Toast.makeText(getBaseContext(),"Time Selected : "+timepicker.getCurrentHour()+":"
                +timepicker.getCurrentMinute(), Toast.LENGTH_SHORT).show();

        }
    });
    }


Output

 


 

Saturday, 1 September 2012

Java Constuctor


  • The constructor in Java have same name as name of class in which they belong.
  • The constructor in java does not have any return type, science never return anything.
  • The main use of constructor is to initialize the value of the reference variable to instance variable. 
  • Java provide a default constructor which takes no arguments and performs no special actions or initializations,when no explicit constructor are provided.


Friday, 31 August 2012

Type conversion


Type Casting  refers to changing an entity of one datatype into another. This is important for the type conversion in developing any application. If you will store a int value into a byte variable directly, this will be illegal operation. For storing your calculated int value in a byte variable you will have to change the type of resultant data which has to be stored.
Automatic Conversion
In Java type conversions are performed automatically when the type of the expression on the right hand side of an assignment operation can be safely promoted to the type of the variable on the left hand side of the assignment. Thus we can safely assign:
byte -> short -> int -> long -> float -> double

lets take an example,
// 64 bit long integer

long myLongValue;

// 32 bit standard integer 

int myIntValue;

myLongValue = myIntValue;

Java follows two types of casting

  • Upcasting
  •  Downcasting

Upcasting
Casting a reference with the class hierarchy in a direction from the sub classes towards the root then this type of casting is termed as upcasting. Upcasting does not require a cast operator.
DownCasting
On the other hand, casting a reference with hierarchal class order in a direction from the root class towards the children or subclasses, then it is known as downcasting.
Here we discussing one example,where we converting int value to byte.

int x=10;
byte b =(byte) x;

here first we assign the int x to 10;Then we try to convert int x to byte and try to store in the variable byte b.for that we using byte b =(byte) x;

Explicit Conversion (Casting)

Automatic type casting does work in case of narrowing i.e. when a data type requiring more storage is converted into a data type that requires less storage. E.g. conversion of a long to an int does not perform because the first requires more storage than the second and consequently information may be lost. In such situations an explicit conversion is required. 

Variable declaration



Variables are nothing but reserved memory locations to store values. This means that when you create a variable you reserve some space in memory.
Based on the data type of a variable, the operating system allocates memory and decides what can be stored in the reserved memory. Therefore, by assigning different data types to variables, you can store integers, decimals, or characters in these variables.



In java programing language all variables must first be declared before they can be used.This structure involves starting the variable’s type and name.

int nm=1;

Doing so tells your program that a field named “nm” using to hold numerical data .Where “int” is the variable data type and “nm” is the variable name.where we initializing the integer nm value as 1.

byte:

  • Byte data type is a 8-bit signed two's complement integer.
  • Minimum value is -128 (-2^7)
  • Maximum value is 127 (inclusive)(2^7 -1)
  • Default value is 0
  • Byte data type is used to save space in large arrays, mainly in place of integers, since a byte is four times smaller than an int.
  • Example : byte a = 100 , byte b = -50

short:

  • Short data type is a 16-bit signed two's complement integer.
  • Minimum value is -32,768 (-2^15)
  • Maximum value is 32,767(inclusive) (2^15 -1)
  • Short data type can also be used to save memory as byte data type. A short is 2 times smaller than an int
  • Default value is 0.
  • Example : short s= 10000 , short r = -20000
int:
  • Int data type is a 32-bit signed two's complement integer.
  • Minimum value is - 2,147,483,648.(-2^31)
  • Maximum value is 2,147,483,647(inclusive).(2^31 -1)
  • Int is generally used as the default data type for integral values unless there is a concern about memory.
  • The default value is 0.
  • Example : int a = 100000, int b = -200000

long:

  • Long data type is a 64-bit signed two's complement integer.
  • Minimum value is -9,223,372,036,854,775,808.(-2^63)
  • Maximum value is 9,223,372,036,854,775,807 (inclusive). (2^63 -1)
  • This type is used when a wider range than int is needed.
  • Default value is 0L.
  • Example : int a = 100000L, int b = -200000L

float:

  • Float data type is a single-precision 32-bit IEEE 754 floating point.
  • Float is mainly used to save memory in large arrays of floating point numbers.
  • Default value is 0.0f.
  • Float data type is never used for precise values such as currency.
  • Example : float f1 = 234.5f

double:

  • double data type is a double-precision 64-bit IEEE 754 floating point.
  • This data type is generally used as the default data type for decimal values. generally the default choice.
  • Double data type should never be used for precise values such as currency.
  • Default value is 0.0d.
  • Example : double d1 = 123.4

boolean:

  • boolean data type represents one bit of information.
  • There are only two possible values : true and false.
  • This data type is used for simple flags that track true/false conditions.
  • Default value is false.
  • Example : boolean one = true

char:

  • char data type is a single 16-bit Unicode character.
  • Minimum value is '\u0000' (or 0).
  • Maximum value is '\uffff' (or 65,535 inclusive).
  • Char data type is used to store any character.
  • Example . char letterA ='A'