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Foreach loop cycle in Java Android example


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Foreach in Java basic example source code.

MainClass.java


public class MainClass {
	public static void main(String[] arg) {
		String[] arrayOfString = { "Hello", "people", "hello", "world!" };

		for (String s : arrayOfString)
			System.out.println(s);

	}
}


397LW NO topic_id




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Další témata ....(Topics)


165

How to clear or hide an ImageView in Android | how-to-clear-or-hide-an-imageview-in-android



// solution 1
ImageView imageView = (ImageView)findViewById(R.id.myimage);
imageView.setImageDrawable(null);
// or
imageView.setImageResource(0);

// solution 2  hide ImageView
imageView.setVisibility(View.INVISIBLE);

// solution 3 resize ImageView 0, 0
 hImageViewSemafor.setLayoutParams(new LinearLayout.LayoutParams(0,0));
67

File open read to StringBuilder close Java example | file-open-read-to-stringbuilder-close-java-example


BufferedReader , FileReader, StringBuilder , readLine, close Java example

Android example

String MYFILE = "my_file";
FileInputStream fis = openFileInput(MYFILE);
	int c; String sText = "";
	while((c=fis.read())!=-1)
	{

		sText += (char)c; // convert int to char
	 }
	fis.close();						



Java example

try {
	    BufferedReader in = new BufferedReader(new FileReader("myfile.txt"));
	    StringBuilder strBuilder = new StringBuilder();
	    String str;
	    while ((str = in.readLine()) != null) {
	       strBuilder.append(str);
	    }
	    in.close();
	} catch (IOException e) {
		e.toString();
	}

313

Difference between logical operators and or Java | difference-between-logical-operators-and-or-java


Basic difference remember it!!!
if(TRUE && TRUE && TRUE) return TRUE otherwise FALSE

if(FALSE || FALSE || FALSE) return FALSE otherwise TRUE

Logical operator and &&
If all conditions/operands is TRUE return TRUE, otherwise return FALSE

if( true and true and true){ 
  // return true - do something
}
int a = 6;
if(a == 6 && a == 6 ) {
 // if TRUE
 // true && true return true, do something
}

if(a == 6 && a == 5){
  // nothing, not attended
}else{
  // true && false return false, or false && false return false 
  // do something
}


Logical operator or ||
The logical OR operator (||) returns the boolean value true if either or both operands is true and returns false otherwise.
If one operands is TRUE, condition is TRUE:

if(FALSE OR FALSE OR TRUE) return TRUE
if(FALSE OR TRUE OR FALSE) return TRUE
if(FALSE OR FALSE OR FALSE) return FALSE

int a = 6;
if(a==6 || a==5){ // TRUE || FALSE return TRUE
  //if return TRUE
  //one from operadns is TRUE return true,  do something
}

if(a==5 || a==4){ // FALSE || FALSE return FALSE
 // not attended
}else{
 //if return FALSE, do something
}

rev
17

double in Java example for Android development | double-in-java-example-for-android-development


Java double is 64 bit double precision type used when fractional
precision calculation is required.

Java double je datový typ (reálné číslo) o velikosti 64 bitů. Používá se například pro přesný výsledek po dělení za desetinnou tečkou. Pokud nepotřebuje tak veliké číslo použijte raději typ float, šetříte tím paměť mobilního telefonu.


		// declaration and assignment of value  type double
		double x = 18.41785;
		//print formated  value
		System.out.printf("The value of x is %.3f%n", x); // 18.418
                
                // declaring more variables in single statement
                double d1 = 12.4, d2 = 564.5, d3 = 14.589;

		// double range of value
		System.out.println(Double.MIN_VALUE); // 4.9E-324
		System.out.println(Double.MAX_VALUE); // 1.7976931348623157E308

		// is NaN  Not-a-Number
		double f = (double) Math.sqrt(-15);
		boolean bNaN = Double.isNaN(f);
		System.out.print(bNaN); // true
		
                // check if a string is a valid number in Java example
                // convert string to double Java example
		String sD = "12.8";
		double dParse = Double.parseDouble(sD);

	       // convert strings to numbers
	      String sDl = "15.48";
	      double dFromString = (Double.valueOf(sDl)).doubleValue();

// format double, float or long value to string
	DecimalFormat formatter = new DecimalFormat(".##");
	String s = formatter.format(-.5678);             // -0.57
// .###  -0.568
// .#### -0.5678
// .000000  -.567800

// -123.456
// .##  -123.46
// #.##  -123.46

// #E0  -.1E3
// ##E0  -1.2E2
//###E0  -123E0

// double to string in Java example code
Double dObj = new Double(68.5);
String str = dObj.toString();
// else 
Double dS = 11.6;
String sdouble = dS.toString();

// compare two double variables
	      Double dComp1 = 4.3;
	      if(dComp1.equals(4.3))
	  		System.out.print("true");

	// compares the two specified double values in Java example
	// int i =	compare(double d1, double d2);
	    int i =	Double.compare(11.5, 11.7); // -1 first < second
	    // 0 first == second
	    // 1 first > second
	    System.out.print(i);


82

Switch Statement Java basic example | switch-statement-java-basic-example


Switch statement with numbers and array of strings Java example.


public class MainClass {
	public static void main(String[] arg) {
		String[] arrayOfString = { "One", "Two", "Three", "Four" };

		int i = 2;
		switch (i) {
			case 1: {
				System.out.println(arrayOfString[i]);
				break;
			}
			case 2: {
				System.out.println(arrayOfString[i]);
				break;
			}
			case 3: {
				System.out.println(arrayOfString[i]);
				break;
			}
			default: {
				System.out.println("Enter a valid value.");
			}
		} // END of switch
	}
}
/*
 * Three
 */




Possible:

case 1:
 System.out.println(arrayOfString[i]);
break;

// i love this notation 
case 1:{
 System.out.println(arrayOfString[i]);
}break;

case 1:{
 System.out.println(arrayOfString[i]);
 break;
}



Editace: 2011-10-04 08:56:58
Počet článků v kategorii: 397
Url:foreach-loop-cycle-in-java-android-example

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