Java Basic Rules
// file name MyFirstClass.java
import java.util.*;
import java.lang.Math;
import java.io.*;
import javax.swing.*;
public class MyFirstClass{ // start of program
public static void main(String[] args) { // basic function main
// variables and calculation
int a=2;
int b=3;
int c=Integer.parseInt(JOptionPane.showInputDialog(" Put number: ", "1"));
System.out.println("Number is: "+c);
System.out.println(a+" * "+b+" = "+(a*b));
System.out.println("a^3 "+Math.pow(a,b));
//array
int[] array_my=new int[10];
array_my[0]=3;
array_my[1]=5;
System.out.println("Number of elements "+array_my.length+" 1 + 2 element of array "+(array_my[0]+array_my[1]));
//strings
String txt="Quick red fox";
String txt2=JOptionPane.showInputDialog("Write text: ", "word");
System.out.println("Text is: "+txt2);
String[] count_of_word=txt.split(" ");
System.out.println("Length: "+txt.length()+" Count of words "+count_of_word.length);
System.out.println(txt +" -> "+txt.replace("red","brown"));
System.out.println("First 5 chars of string is: "+ txt.substring(0,5));
//for a if
for(int i=0; i<10;i++){
if(i==3)System.out.println("i equal "+i);
}
// file
try {
File soubor=new File("some_file.txt");
if(!soubor.exists()){
System.out.println("File dont exist");
}
else { // utf-8 encoding
BufferedReader in1 = new BufferedReader(new InputStreamReader(new FileInputStream(soubor),"UTF-8"));
BufferedWriter out1 = new BufferedWriter(new OutputStreamWriter(new FileOutputStream("zapis.txt"),"UTF-8"));
String str;
while ((str = in1.readLine())!=null){
System.out.println(str);
out1.write(str+"
");
}
in1.close();
out1.close();
}
} catch(IOException e){System.out.println("Error " + e);}
// dir
File pathName = new File("some_dir");
String[] fileNames = pathName.list();
if(pathName.exists())
System.out.println("Name of first file in "some_dir": "+fileNames[0]);
else System.out.println("dir not exist");
//function
int nResult = calculateMyFc(3,5);
System.out.println("Result of function: "+nResult);
} // end of function main
// new function , you can add to end MyFc = my function
public static int calculateMyFc(int a, int b){
return (a+b);
}
} // end of class of program
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Samsung Galaxy Ace je chytrý telefon s operačním systémem Android.
Samsung Galaxy Ace je (22.února2012) 4. nejpoužívanějším chytrým telefonem u programu Sky Map viz tabulka.
Galaxy Ace je 3.5G smartphone nabízí i quad-band GSM. Displej je 3,5 palcový TFT kapacitní dotykový LCD HVGA s (320x480) rozlišením. K dispozici je také 5 megapixelový fotoaparát s LED bleskem. Je schopny zaznamenat video v rozlišení QVGA (320x240) a VGA s (640x480) rozlišením. Ace je dodáván s 1350mAh Li-Ion baterií. Ace běží s OS Android 2.2 Froyo a lze jej upgradovat na Android 2.3.6 Gingerbread.
Samsung Galaxy Ace photo pic image
Zdroj obrázku: wikipedia
Html.fromHtml(), setText(), textView.setText(Html.fromHtml(String htmlFormat)), Android example.
TextView mIdTextOk = (TextView)findViewById(R.id.idTextOk);
int _nOk = 57;
// number 57 will bold style
mIdTextOk.setText(Html.fromHtml( "OK: "+"<b>"+_nOk+"</b>"));
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public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
String sPackagePath = getPackageResourcePath();
}
drawOval(), setStrokeWidth(), setStyle()
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(new SampleView(this));
}
private static class SampleView extends View {
// CONSTRUCTOR
public SampleView(Context context) {
super(context);
setFocusable(true);
}
@Override
protected void onDraw(Canvas canvas) {
canvas.drawColor(Color.CYAN);
Paint p = new Paint();
// smooths
p.setAntiAlias(true);
p.setColor(Color.RED);
p.setStyle(Paint.Style.STROKE);
p.setStrokeWidth(4.5f);
// opacity
//p.setAlpha(0x80); //
canvas.drawOval(new RectF(50, 50, 20, 40), p);;
}
}
}
TimerTask with updating of TextView here
//android.okhelp.cz/asynctask-example-android-with-progressbar/
//android.okhelp.cz/timer-task-timertask-run-cancel-android-example/
package cz.okhelp.timer;
import java.util.Timer;
import java.util.TimerTask;
import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;
public class TimerActivity extends Activity {
TextView hTextView;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
hTextView = (TextView)findViewById(R.id.idTextView);
MyTimerTask myTask = new MyTimerTask();
Timer myTimer = new Timer();
// public void schedule (TimerTask task, long delay, long period)
// Schedule a task for repeated fixed-delay execution after a specific delay.
//
// Parameters
// task the task to schedule.
// delay amount of time in milliseconds before first execution.
// period amount of time in milliseconds between subsequent executions.
myTimer.schedule(myTask, 3000, 1500);
}
class MyTimerTask extends TimerTask {
public void run() {
// ERROR
hTextView.setText("Impossible");
// how update TextView in link below
// //android.okhelp.cz/timer-task-timertask-run-cancel-android-example/
System.out.println("");
}
}
}
//android.okhelp.cz/asynctask-example-android-with-progressbar/
//android.okhelp.cz/timer-task-timertask-run-cancel-android-example/
Editace: 2013-12-09 11:06:19
Počet článků v kategorii: 396
Url:java-basic-rules
