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Unable to display textview on button click in android

I want to create this textview, and then display it after this button is clicked, but no textview is displayed.
I dont't want to use findViewById(), if possible, because I want to create a new textview every time the button is pressed. I've tried making a linear layout first, but I've seen a lot of websites say that you don't need to, and I would prefer not to. Any advice would be helpful. Thank you.
EditText name=layout.findViewById(R.id.enterName);
final String Name=name.getText().toString();
Button create=layout.findViewById(R.id.create);
create.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
TextView ProgrammaticallyTextView = new TextView(MainActivity.this);
ProgrammaticallyTextView.setText(Name);
ProgrammaticallyTextView.setTextSize(22);
popup.dismiss();
}
});
There are no error messages and the logcat doesn't say that anything is wrong.

Try like this :
private LinearLayout lLayout;
private EditText lEditText;
private Button lButton;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
lLayout = (LinearLayout) findViewById(R.id.linearLayout);
lButton = (Button) findViewById(R.id.button);
lEditText = (EditText) findViewById(R.id.editText);
lButton.setOnClickListener(onClick());
TextView textView = new TextView(this);
textView.setText("Text New");
}
private OnClickListener onClick() {
return new OnClickListener() {
#Override
public void onClick(View v) {
lLayout.addView(createTextView(lEditText.getText().toString()));
}
};
}
private TextView createTextView(String text) {
final LayoutParams loutParams = new
LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
final TextView textView = new TextView(this);
textView.setLayoutParams(loutParams );
textView.setText("Text is " + text);
return textView;
}

Use the activity's findViewById() method to reference your layout views. For example, you can replace
EditText name=layout.findViewById(R.id.enterName);
Button create=layout.findViewById(R.id.create);
with
EditText name=getActivity().findViewById(R.id.enterName);
Button create=getActivity().layout.findViewById(R.id.create);
Note: if you are not using fragments then there is no need to use getActivity since findViewById() is a method of the superclass AppCompactActvity( or Activity).
I guess your code is not working because the Button View and Editext Views have not been reference when activity starts for the oncreate() method

How can I automatically clear the text in EditText?

final TextView textView = (TextView) findViewById(R.id.textView);
final EditText editText = (EditText) findViewById(R.id.editText);
Button button = (Button) findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String etString = editText.getText().toString();
textView.setText(etString);
}
});
I am new to coding and I don't know how to automatically clear the text in an EditText so the user doesn't have to do it themselves. You can see in all "big" websites that when you enter text into a text box (for example: "What's your name?") you see "first name" in the text box and when you click on it, it disappears. How can I make the text disappear automatically without the user having to delete it manually?

What you're referring to isn't actually text that's being set -- it's a hint (which is why it doesn't show after the EditText is focused or text has already been entered). You can set these placeholder hints in your EditText XML, for example:
android:hint="First Name".
If you're feeling really adventerous, you can also wrap your EditText in a TextInputLayout for a Material Design style floating hint.
If that helps, be sure to accept this answer.

You can do it grammatically by modifying your code to use the hint property:
editText.setText("");
editText.setHint(<string>);
also you can change color by adding
editText.setHintTextColor(<some color>);

Get access to another View from a Button's onClick method

I have a ListView in my app.
Its items have a Button and an invisible text field; I want to make the text field visible when the Button is pressed.
How can I do it from the onClick(View v) method of OnClickListener's object?
Maybe it's something like "getParent().findViewById()", but getParent() doesn't return a View..

You could set the tag of the button view to the TextView.
Then you can use v.getTag() to get it back, then do what you want with it.
Otherwise, make the TextView final in your adapter getView method after finding it , then simply use it within the click event

If you want to visible the textView
#Override
public void onClick(View view) {
switch (view.getId()){
case R.id.btn:
yourtextView.setVisibility(View.VISIBLE);
break;
}
}

try this
View view = listview.getAdapter().getView(0,null,null);
TextView textView = view.findViewById(R.id.textView);

Simple validation of editText not working (Eclipse)

I'm a beginner to Java and I want to validate an EditText. What I have in mind: my editText has to match "helloworld". When you press a button this has to be validated. If this is true--> go to a new class in which I have a setContentView to display a new layout.
If the text which I have just typed does not match "helloworld", it should do nothing. It seems very easy but since I'm a beginner you would help me BIGTIME!

Here's most of the logic handled. You will need to fill in your actual layout id's and make your launch intent. Put this code in your onCreate method in the activity with the layout that contains the edit text box
EditText editText = (EditText)findViewById(R.id.editTextBox);
Button btn = (Button)findViewById(R.id.checkBtn);
btn.setOnClickListener(new OnClickListener(){
#Override
public void onClick(View v) {
if(editText.getText().toString().equalsIgnoreCase("helloworld")){
//Launch activity with new view
}
}
});

In an activity (or android class) you have to get the instance of your EditText. Your edit text has an id, and you can get it using R. R is the resources for your app.
EditText t = (EditText)findViewById(R.id.<Name of your textfield>);
Then you can get the value of that textfield and compare it
t.getText().toString().equals("helloworld");
will return true or false. If you dont care about the case of the letters use
t.getText().toString().toLowerCase().equals("helloworld");
you will need an onClickListener for your button, check out the android api
http://developer.android.com/reference/android/view/View.OnClickListener.html
in your onCreate, when declaring your submit button, add a listener
Button submit = (Button) findViewById(R.id.submit);
submit.setOnClickListener(submitListener);
make a new onClick listener and fire an Intent to start a new activity
View.OnClickListener submitListener = new View.OnClickListener() {
public void onClick(View v) {
//if string matches helloworld fire new activity
Intent newActivity = new Intent();
startActivity(newActivity);
}
};

// create a reference to the EditText in your layout
EditText editText = (EditText)findViewById(R.id.editTextIdInLayout);
// create a reference to the check Button in your layout
Button btn = (Button)findViewById(R.id.buttonIdInLayout);
// set up an onClick listener for the button reference
btn.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
String userInput = editText.getText().toString(); // get the user input
if (userInput.equals("helloworld") // see if the input is "helloworld"
{
setContentView(R.layout.newLayout); // change the content view
}
}
});

Can java do printIn in Android?

I have an EditText, and when a button is clicked, I want the text to be displayed on the screen. And the EditText can be used again to add other text and on and on. Thanks!
Something like:

EditText et = (EditText)findviewById(R.id.et1);
TextView display = (TextView)findviewById(R.id.tv1);
plusBtn.setOnClickListener(new OnClickListener() {
public void onClick(View v)
{
tv1.setText(tv.getText().toString()+"\n"+et.getText().toString());
//prints the text from edittext and concatinates it to the textview previous text
}
});

Please use below code for that, it will solve your problem.
EditText editText1 = (EditText)findviewById(R.id.editText1);
TextView textView1 = (TextView)findviewById(R.id.textView1);
plusBtn.setOnClickListener(new OnClickListener() {
public void onClick(View v)
{
textView1.append("\n"+editText1.getText().toString());
// OR
textView1.setText(textView1.getText().toString()+"\n"+editText1.getText().toString());
}
});

You can add Views to your Layout by using its addView() Method. So you could add a TextView upon each button-click which contains the content of your TextField.