why am I getting "cannot find symbol class textview" ?

Hi,

First of all you need a start Tag for each defined TextView,Button,....

For example:

android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="End the World"
android:id="@+id/endbutton"
android:layout_below="@+id/textView"
android:layout_alignRight="@+id/textView"
android:layout_alignEnd="@+id/textView"
android:layout_marginTop="47dp"
android:onClick="myendMethod"
/>

or

android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="This is a dumb test"
android:id="@+id/textView1"
android:textColor="#ad0b0b"
/>

do you have an onCreate method?

If no, you must implement it in your Activity!

example:

@Override

protected void onCreate(Bundle savedInstanceState{
super.onCreate(savedInstanceState);
setContentView(R.layout.name_of_your_xml_file_which_has_the_layout); 
TextView textView;
textView = (TextView)findViewById(R.id.id_of_the_textView_as_given_in_your_layout.xml);
textView.setTextSize(40);
textView.setText("TEST");

}

If you missed that out i would propose that you first read a book on android development or check out developer.android. com /guide/ index.html

// assuming that this is a button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="End the World"
android:id="@+id/endbutton"
android:layout_below="@+id/textView"
android:layout_alignRight="@+id/textView"
android:layout_alignEnd="@+id/textView"
android:layout_marginTop="47dp"
android:onClick="myendMethod"
/>

android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="This is a dumb test"
android:id="@+id/textView1"
android:textColor="#ad0b0b"
/>

public void onCreate(Bundle b){

setContentView(R.layout.your xml name);

// Initialize the TextView in Class not in the method

TextView textView = (TextView)findViewById(R.id.textView1);

}

public void myendmethod(View v)
{
int count=7;
textView.setText(String.Valueof(count));

}

Try this one

The oncreate routine programmed itself during the visual development, so I added your code and get this error:FRUSTRATING:
Error24, 9) error: cannot find symbol class TextView

my code below:

package com.example.theboss.having_fun;

import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    setContentView(R.layout.content_main);
    TextView textView;
    textView = (TextView)findViewById(R.id.textView1);
    textView.setTextSize(40);
    textView.setText("TEST");

    FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
    fab.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                    .setAction("Action", null).show();
        }
    });
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.menu_main, menu);
    return true;
}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle action bar item clicks here. The action bar will
    // automatically handle clicks on the Home/Up button, so long
    // as you specify a parent activity in AndroidManifest.xml.
    int id = item.getItemId();

    //noinspection SimplifiableIfStatement
    if (id == R.id.action_settings) {
        return true;
    }

    return super.onOptionsItemSelected(item);
}


public void myendmethod(View v)
{
    int count=7;
    TextView textView = (TextView)findViewById(R.id.textView1);

}

}

any clues?
BTW, I had to log in via google, the change pwd feature for this site DOES NOT work, it's useless

— modified on Apr 10, 2016, 10:07:39 PM

You need to add import android.widget.TextView; into import section.

— modified on Apr 10, 2016, 10:40:17 PM

Thanks for the reply. I got frustrated and went back to my orig project, added your line from above
" import android.widget.TextView;" and that took care of that error.
When I click on the "endtheworld" button, nothing happens, but at least I get NO ERRORS!
Can you advise?

public void endtheworld(View view) {
// Do something in response to button click
int zcount=7;
TextView textView = (TextView)findViewById(R.id.textView1);
System.out.println("FROG");

android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Push to end the world"
android:id="@+id/endbutton"
android:layout_marginLeft="38dp"
android:layout_marginStart="38dp"
android:background="#ccb3b3"
android:layout_below="@+id/endbutton"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="14dp"
android:onClick="endtheworld"
/>

android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Frogs are green"
android:layout_alignParentTop="true"
android:layout_alignLeft="@+id/endbutton"
android:id="@+id/textView1"
/>

public void myendmethod(View v)
{
int count=7;
TextView textView = (TextView)findViewById(R.id.textView1);

}

Coz you are not doing any thing on button click. If you want to check may be you can try

myendmethod should be defined in xml like

android:onClick="myendmethod"

public void myendmethod(View v)
{
int count=7;
TextView textView = (TextView)findViewById(R.id.textView1);
textView.setText(String.valueof(count));
}

}

Error now is:
Error50, 32) error: cannot find symbol method valueof(int)
I thought I was having the button do something, that is: System.out.println("FROG");
Print the word "frog" but although I dont see output in the log I see:
04-12 20:32:11.292 2302-2302/com.example.theboss.myapplication_apr I/System.out: FROG

— modified on Apr 13, 2016, 2:33:16 AM

setText(String.valueOf(count));

or

setText(""+count);

try this

Your tip worked. But that was not my problem. When I output, my button is hiding where the count gets displayed. I need to move the button, but my button has the id of textView1!

Your Button id is endbutton so on the method as per by xml you mentioned in above post i.e. endtheworld

// put this line in onCrate

endbutton = (Button)findViewById(R.id.endbutton);

// As i did not get any thing which hide you button but still it is hiding use this

public void endtheworld(View v ){
endbutton.setVisibility(View.Visisble);
endbutton.setText(""+count);
}

Yes, got it! thanks for the help, still a newbie here and I have this test app successfully ported to my Moto E phone, all in fun.

Another quest, I am trying to display a counting loop iterating and want to display in a textview, should this work? I tried to slow it down using a nested loop but I do not get the continual numbers displaying, rather it just displays 199 whens its done
my code:

public void mynumbers(View v) {
TextView tv2 = (TextView) findViewById(R.id.textView2);
tv2.setVisibility(View.VISIBLE);

    for(int i=0; i < 200; i++)
    {
        for(int j=0; j < 1150200; j++) {}
            String strI = String.valueOf(i);
            tv2.setText(strI);
         }
        }

— modified on Apr 23, 2016, 2:31:44 PM

In your simple app you can use Thread.sleep(50) before tv2.setText(strI);, but a better idea is to use CountDownTimer for pause.

— modified on Apr 23, 2016, 3:17:17 PM

the thread.sleep gives me:
Error118, 25) error: unreported exception InterruptedException; must be caught or declared to be thrown

Then I found:
try{ Thread.sleep(10); }catch(InterruptedException e){ }
no errors, but there was no continual display of counting, just went right to 199 ;(

— modified on Apr 23, 2016, 5:47:29 PM

Is your code similar?

String strI;
for(int i=0; i < 200; i++)
{
try { Thread.sleep(10);
} catch(InterruptedException e){ }
strI = String.valueOf(i);
tv2.setText(strI);
}

Yes

for (int i = 0; i < 200; i++) {
String strI = String.valueOf(i);
try{ Thread.sleep(10); }catch(InterruptedException e){ }
tv2.setText(strI);

    }

10 ms is very little time, so eyes can't see changes. Try:
.........
for (int i=1; i < 30; i++)
.........
try{ Thread.sleep(100); }catch(InterruptedException e){ }
..........

Nope, still nothing appears until it's done counting.
I had to use 30 because at 100, the app timeouts says "not responding" do I want to wait or close it

— modified on Apr 24, 2016, 2:42:55 PM

Anyway thread.sleep() is not a best technique. Use CountDownTimer instead, for example:

String strI;
int tick = 0;

CountDownTimer timer = new CountDownTimer(2000, 25) {

        @Override
        public void onTick(long l) {
               tick++
               strI = String.valueOf(tick);
               tv2.setText(strI);
        }

        @Override
        public void onFinish() {
        }
    };

I get this now
Error103, 17) error: local variable tick is accessed from within inner class; needs to be declared final

I pasted in your code.

Make variable "tick" global or put declaration into timer's brackets.

the global route seems quite complicated, so I did this, putting variables within CountDownTimer's brackets, now no numbers show. I appreciate the help you are providing

public void mynumbers(View v) {
// TextView tv2 = (TextView) findViewById(R.id.textView2);
// tv2.setVisibility(View.VISIBLE);

   // String strI;
  //  int tick = 0;

    CountDownTimer timer = new CountDownTimer(2000, 25) {
        int tick = 0;
        String strI;
        TextView tv2 = (TextView) findViewById(R.id.textView2);

        @Override
        public void onTick(long l) {
            tick++;
           strI = String.valueOf(tick);
            tv2.setText(strI);
        }

        @Override
        public void onFinish() {
        }
    };
}

This code should work:

public class MainActivity extends Activity {

    TextView tv2;
    int tick;
    String strI;

    CountDownTimer timer = new CountDownTimer(5000, 50) {

        @Override
        public void onTick(long l) {
            tick++;
            strI = Integer.toString(tick);
            tv2.setText(strI);
        }

        @Override
        public void onFinish() {
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        tv2 = (TextView) findViewById(R.id.textView2);
    }

    public void mynumbers(View v) {
        tick = 1;
        timer.start();
    }
}

YES!!
working now. and thank you.
One thing, my line here is a bit different then yours, why?

public class MainActivity extends AppCompatActivity {

AppCompatActivity is a safe to use backward compatibility class. It brings a single consistent ActionBar for all devices starting with API Level 7 (Android 2.1) and above. Android Studio uses AppCompatActivity by default.