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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

opening new content view

In my Main.class I am creating a dynamic ScrollView and starting it using setContentView(sv) it displays a Spinner and a Button.
The user selects an option from the Spinner and then clicks the Button. I have set a setOnClickListener to the Button.
In the onClick method I am trying to start up a new ContentView. Calling a new class file with the same type of layout as Main.class. Not sure how to go about doing this. I added finish() to the onClick method and it closes the original window but not sure how to open the new one.
Here is the Main.class code:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.messages = new Messages(this);
this.datasource = new FacilitiesDataSource(this);
this.datasource.open();
ScrollView sv = new ScrollView(this);
LinearLayout ll = new LinearLayout(this);
ll.setOrientation(LinearLayout.VERTICAL);
sv.addView(ll);
Spinner s = new Spinner(this);
s.setId(SPINNER_FACILITIES);
s.setLayoutParams(new Spinner.LayoutParams(-2,-1));
final List<SpinnerObject> list = this.datasource.getFacilitiesList();
final ArrayAdapter<SpinnerObject> adapter = new ArrayAdapter<SpinnerObject>(this, android.R.layout.simple_spinner_dropdown_item, list);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
s.setAdapter(adapter);
ll.addView(s);
Button b = new Button(this);
b.setText("Submit");
b.setLayoutParams(new LayoutParams(-2,-1));
b.setOnClickListener(new OnClickListener(){
#Override
public void onClick(View arg0) {
Spinner spin = (Spinner)findViewById(SPINNER_FACILITIES);
Log.v("option picked", Integer.toString(( (SpinnerObject) spin.getSelectedItem () ).getId () ));
/*
* NEED HELP HERE
* NEED HELP HERE
* NEED HELP HERE
*/
//finish();
}
});
ll.addView(b);
setContentView(sv);
}
Here is my Vehicles.class:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Log.v("Started onCreate", "Vehicle");
ScrollView sv = new ScrollView(this);
setContentView(sv);
}

I assume you mean you want to start a new Activity (from Main to Vehicles). In that case you can use the following code:
Intent intent = new Intent(Main.this, Vehicle.class);
startActivity(intent);
Make sure all Activity classes are declared in your Android Manifest file, inside the <application> tag, like this:
<activity android:name=".Vehicles" />

How to programatically make RelativeLayout that works

I have a problem with creating a working Layout in View class that will not crush the program. I think everything is done correctly in the code, but probably there are some setting I don't know about I hope that You guys will reveal that to me.
I am trying to do drawing View with a "Clear" button and RadioGroup.
So first od all, that works fine, but both added content Views (btnReset = "Clear", btnScale = RadioGroup) are hoovered on each other. That is why I want to add one parent Layout, so I can easily manage these Views.
File1.java
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
DrawView tv = new DrawView(this);
setContentView(tv);
addContentView(tv.btnReset, tv.params);
addContentView(tv.btnScale, tv.paramsRadio);}
DrawView.java
public class DrawView extends View {
public Button btnReset;
public RelativeLayout.LayoutParams params;
public RelativeLayout.LayoutParams paramsRadio;
public RadioGroup btnScale;
public DrawView(Context context) {
super(context);
btnReset = new Button(context);
btnReset.setText("Clear Screen");
btnScale = new RadioGroup(context);
btnScale.setOrientation(RadioGroup.HORIZONTAL);
params = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.MATCH_PARENT,
RelativeLayout.LayoutParams.WRAP_CONTENT);
paramsRadio = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.MATCH_PARENT,
RelativeLayout.LayoutParams.WRAP_CONTENT);
I omit most of the code because I think its irrelevant, everything works fine but the layout.
Anyway, when I try to create a layout, I simply add a little code:
Changed File1.java
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
DrawView tv = new DrawView(this);
setContentView(tv);
addContentView(tv.layout, tv.params); }
Changed DrawView.java
public class DrawView extends View {
public Button btnReset;
public RelativeLayout.LayoutParams params;
public RelativeLayout.LayoutParams paramsRadio;
public RelativeLayout layout;
public RadioGroup btnScale;
public DrawView(Context context) {
super(context);
btnReset = new Button(context);
btnReset.setText("Clear Screen");
btnScale = new RadioGroup(context);
btnScale.setOrientation(RadioGroup.HORIZONTAL);
params = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.MATCH_PARENT,
RelativeLayout.LayoutParams.WRAP_CONTENT);
paramsRadio = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.MATCH_PARENT,
RelativeLayout.LayoutParams.WRAP_CONTENT);
layout.addView(btnReset, params);
layout.addView(btnScale, paramsRadio);
I assume that should work like charm, but unfortunately, when I try to do anything with newly created layout, my app crashes. What is wrong with that code?

Well, after quite long fight I managed to solve my own problem :D I did not do it, like #pskink suggested, because honestly for me it was too advanced. I found much simpler solution.
The thing is, You can create as much views as You want in DrawView.java, but sort them in Layout created in File1.java!
Just like that:
File1.java
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
LinearLayout ll = new LinearLayout(this);
ll.setOrientation(LinearLayout.VERTICAL);
DrawView tv = new DrawView(this);
ll.addView(tv.btnReset, tv.params);
ll.addView(tv.btnScale, tv.paramsRadio);
ll.addView(tv);
setContentView(ll);
And DrawView.java stays the same:
public class DrawView extends View {
public Button btnReset;
public LinearLayout.LayoutParams params;
public LinearLayout.LayoutParams paramsRadio;
public RadioGroup btnScale;
public DrawView(Context context) {
super(context);
btnReset = new Button(context);
btnReset.setText("Clear Screen");
btnScale = new RadioGroup(context);
btnScale.setOrientation(RadioGroup.HORIZONTAL);
params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT,
LinearLayout.LayoutParams.WRAP_CONTENT);
paramsRadio = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT,
LinearLayout.LayoutParams.WRAP_CONTENT);

How to access views by id from tabHost?

I have tabHost widget with dynamic created tabs.
In each of newly created tab, there is relative layout with some views (textView, listView etc).
My question is: how to access to these views and how to append new content there? I tried with setting ids or tags, but i didn't work.
public class Main extends Activity {
#Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.main);
final TabHost tabs=(TabHost)findViewById(R.id.tabhost);
tabs.setup();
TabHost.TabSpec spec=tabs.newTabSpec("buttontab");
spec.setContent(R.id.form);
spec.setIndicator("Search-form");
tabs.addTab(spec);
Button btn=(Button)tabs.getCurrentView().findViewById(R.id.buttontab);
btn.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
final TabHost.TabSpec spec=tabs.newTabSpec("tag1");
spec.setContent(new TabHost.TabContentFactory() {
public View createTabContent(String tag)
{
// Creating a new RelativeLayout
RelativeLayout relativeLayout = new RelativeLayout(Main.this);
// Defining the RelativeLayout layout parameters.
RelativeLayout.LayoutParams rlp = new RelativeLayout.LayoutParams(
RelativeLayout.LayoutParams.FILL_PARENT,
RelativeLayout.LayoutParams.FILL_PARENT);
TextView t = new TextView(Main.this);
// t.setId(12); //This dosen't work
t.setText("Searching in progress. Please wait...");
ListView resultsList = new ListView(Main.this);
//Here: array adapter etc
// Adding the TextView to the RelativeLayout as a child
relativeLayout.addView(t);
relativeLayout.addView(resultsList);
return relativeLayout;
}
});
spec.setIndicator("Tab with results");
tabs.addTab(spec);
new GetData(Main.this).execute();
}
});
}
public void appendResultsToViews(String result)
{
//Here i need to access TextView from tab with specific tag and append results to TextView, which was created dynamically earlier
}
Thank you for your help.

set tag of child view and use findViewWithTag(tag)

Android: Create EditText on Runtime

I'm trying to create a view where the user can click a "plus" button, and have additional EditTexts be created. The goal is to have a base of 2 EditTexts, and each time the user clicks the button, add another 2 EditTexts.
How can I do this? I can add EditTexts from Java, but I can't figure out how to add and handle a list of them dynamically.
I was hoping to take however many pairs of EditTexts, and push it into a key/value HashMap or something.
Any ideas of how to do this? Thanks!

public class MyActivity extends Activity {
private LinearLayout main;
private int id = 0;
private List<EditText> editTexts = new ArrayList<EditText>();
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
main = new LinearLayout(this);
main.setOrientation(LinearLayout.VERTICAL);
Button addButton = new Button(this);
addButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View arg0) {
addEditText();
}
});
Button submit = new Button(this);
submit.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View arg0) {
for (EditText editText : editTexts) {
editText.getText().toString();
// whatever u want to do with the strings
}
}
});
main.addView(addButton);
main.addView(submit);
setContentView(main);
}
private void addEditText() {
LinearLayout editTextLayout = new LinearLayout(this);
editTextLayout.setOrientation(LinearLayout.VERTICAL);
main.addView(editTextLayout);
EditText editText1 = new EditText(this);
editText1.setId(id++);
editTextLayout.addView(editText1);
editTexts.add(editText1);
EditText editText2 = new EditText(this);
editText2.setId(id++);
editTextLayout.addView(editText2);
editTexts.add(editText2);
}

Do it in a ListView.
Then you can just add them to a ListAdapter.
And then use adapter.notifyDatasetChanged()

May be I am not clear but Instead of adding Individual edit text you can add as Group View like Linear layout here you can use any flag values to add dynamic name conversions also.
That view you can update into List View like inflating rows in the List View....