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Timer task TimerTask run cancel Android example



Update TextView from TimerTask, Handler, schedule, run, cancel TimerTask, Android example

public class TimerActivity extends Activity {
	TimerTask mTimerTask;
	final Handler handler = new Handler();
	Timer t = new Timer();	
TextView hTextView;
TableRow hTableRow;
Button hButton, hButtonStop;


private int nCounter = 0;
@Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        hTextView = (TextView)findViewById(R.id.idTextView);
        hButton = (Button)findViewById(R.id.idButton);
        hButton.setOnClickListener(mButtonStartListener);
        hButtonStop = (Button)findViewById(R.id.idButtonStop);
        hButtonStop.setOnClickListener(mButtonStopListener);

         
        
    } // end onCreate

View.OnClickListener mButtonStartListener = new OnClickListener() {
	public void onClick(View v) {
		doTimerTask();
    }
};



	
	View.OnClickListener mButtonStopListener = new OnClickListener() {
    	public void onClick(View v) {
    		stopTask();
    		
    	}
    };
    
    
    public void doTimerTask(){

    	mTimerTask = new TimerTask() {
    	        public void run() {
    	                handler.post(new Runnable() {
    	                        public void run() {
    	                        	nCounter++;
                                        // update TextView
    	                        	hTextView.setText("Timer: " + nCounter);

    	                        	Log.d("TIMER", "TimerTask run");
    	                        }
    	               });
    	        }};

            // public void schedule (TimerTask task, long delay, long period) 
    	    t.schedule(mTimerTask, 500, 3000);  // 

    	 }

    	  public void stopTask(){

    	   if(mTimerTask!=null){
    	      hTextView.setText("Timer canceled: " + nCounter);

    	      Log.d("TIMER", "timer canceled");
    	      mTimerTask.cancel();
    	 }
    
    }    
}



397LW NO topic_id



Další témata ....(Topics)


158

Check Internet connection Android example | check-internet-connection-android-example



public boolean isConnected() {
	 try {
		ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
		 return cm.getActiveNetworkInfo().isConnectedOrConnecting();
	} catch (Exception e) {
		// TODO Auto-generated catch block
		e.printStackTrace();
		Log.e("isConnected", e.getMessage());
		Toast.makeText(getApplicationContext(), e.getMessage(),
				Toast.LENGTH_LONG).show();
		return false;
	}


77

break statement in Java Android example | break-statement-in-java-android-example


break statement in Java Android basic example

MainClass.java

public class MainClass {
	public static void main(String[] arg) {
		String[] arrayOfString = {"nothing", "Hello", "people"
				, "bye-bye", "hello", "world!", "end" };
		
		for (int i = 0; i < arrayOfString.length; i++) {
				System.out.println(arrayOfString[i]);
				if(i > 2) 
					break; // end of loop
		}
	}
}
/*
nothing
Hello
people
bye-bye
*/
311

Where Eclipse stored Settings and Templates Java Code | where-eclipse-stored-templates-java-code



C:\documents\workspace\.metadata\.plugins\org.eclipse.core.runtime\.settings\org.eclipse.jdt.ui.prefs
295

Java Basic Rules | 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
332

Android Studio reduce memory usage of PC | android-studio-reduce-memory-usage


File->Settings->Plugins and disable some plugins:

  • Google Cloud Testing

  • Google Cloud Tools Core

  • Google Cloud Tools for Android Studio

  • CVS Integration

  • Git Integration

  • GitHub

  • hg4idea

  • Subversion Integration


Use Emulator AVD with small memmory usage. For example: Virtual tablet with hight resolution have big memmory usage. Virtual phone with 240x320 resolution have small memmory usage.

Use instaed of Emulator, real device connected by USB (smarphone Samsung Galaxy or other recommended by Google whit debugable mode).

If you notice that Android Studio works slowly, consider the possibility to reduce the number of folders under antivirus protection.
Each antivirus check in your project consumes resources. You can significantly improve the performance, if you exclude certain folders from the antivirus protection.


Editace Jana Žákovská : 2011-10-03 13:57:17
Počet článků v kategorii: 397
Url:timer-task-timertask-run-cancel-android-example
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