CountDownTimer on Android

Question

I use a countdown timer, but it does not work for me. Below is the code.

package FinalProj.com; import android.app.Activity; import android.os.Bundle; import android.view.View; import android.widget.TextView; import android.os.CountDownTimer; public class iFallApp extends Activity{ public TextView textView1; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); //TextView textview = new TextView(this); //textview.setText("This is the iFall tab"); // setContentView() setContentView(R.layout.ifallapp); textView1=(TextView) findViewById(R.id.textView1); MyCount counter = new MyCount(5000,1000); counter.start(); } public class MyCount extends CountDownTimer{ public MyCount(long millisInFuture, long countDownInterval) { super(millisInFuture, countDownInterval); } iFallApp app1 = new iFallApp(); @Override public void onFinish() { // TODO Auto-generated method stub textView1.setText("done"); } @Override public void onTick(long millisUntilFinished) { // TODO Auto-generated method stub textView1.setText((int) (millisUntilFinished/1000)); } } } 

Answer 1

This line is causing the problem;

 textView1.setText((int) (millisUntilFinished/1000)); 

What you do is set the resource identifier for textView1, while what you are looking for is something like:

 textView1.setText(Long.toString(millisUntilFinished/1000)); 

Also a string;

  iFallApp app1 = new iFallApp(); 

Pretty suspicious. Remove it just in case before using it accidentally. You already have an iFallApp created by the Android platform, and you can pass it using this if necessary.

Answer 2

And for other developers, they follow as an example, but they distracted their timer into their own class class. Passing a TextView to an instance of CountDownTimer will result in a memory leak if you do not clean the links thoroughly. This will be obvious after turning the screen half a dozen times, your application will crash using OutOfMemoryError, just like me.

Add a method to your CountDownTimer, like this one, and call it whenever onDestroy () / onDestroyView () is called in the activity / fragment that belongs to it.

 public void safeCancel() { this.textView1 = null; super.cancel(); } 

Answer 3

Typically, you can look at the output of adb logcat to determine what is going wrong.

At the top of my head, I would say that the variable textView1 incorrectly set and is zero.

In addition, I would start the countdown timer in the onResume() function, not the onCreate() function.