Develop Reference

Refering to a xml layout inside a widget's class

So, I am trying to get reference to a xml layout from the class of a simple widget I made.
So ,my widget contains an ImageView and two TextViews.I will add the code for this widget, just so no one gets confused.
public class Item extends LinearLayout{
TextView tv1,tv2;
ImageView img;
public Item(Context context,int resid, String t1, String t2) {
super(context);
setOrientation(HORIZONTAL);
setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
}
});
img = new ImageView(context);
tv1 = new TextView(context);
tv2 = new TextView(context);
img.setBackgroundResource(resid);
img.setVisibility(View.VISIBLE);
img.setLayoutParams(new ViewGroup.LayoutParams(200, 200));
tv1.setText(t1);
tv1.setTextSize(15);
tv1.setGravity(Gravity.CENTER);
tv1.setLayoutParams(new ViewGroup.LayoutParams(250, 100));
tv2.setText(t2+"lei");
tv2.setTextSize(15);
tv2.setGravity(Gravity.CENTER);
tv2.setLayoutParams(new ViewGroup.LayoutParams(250,100));
tv1.setBackgroundColor(Color.GREEN);
tv2.setBackgroundColor(Color.BLUE);
addView(img);
addView(tv1);
addView(tv2);
}
So, as you can see, there's a clickListener added for each "Item".What I want to do ,is to be able to refer to a xml layout that is a second activity ,so that I can manipulate what is in this layout from within this widget.
The second activity's class:
public class Final extends Activity {
LinearLayout fl;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.final_layout);
View rootView = getWindow().getDecorView().findViewById(android.R.id.content);
fl = (LinearLayout) rootView.findViewById(R.id.fl);
}
}
The XML file for this second activity:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:id="#+id/fl"
android:layout_width="match_parent"
android:layout_height="match_parent">
</LinearLayout>
So, once again, to sum up, I want to be able to add stuff to this second activity ,from the class Item ,but I am not able to take reference to the XML layout coresponding to the second activity.

So,practically ,the only way to do this, is to pass variables through the onclick method.
What I am doing right now is this: I get two String variables and one Int.Strings being used for the text wrote in textViews and int for the resource ID for the imageView's backgroundResource, pass them to the second activity and use them there to re-create the Item.
If anyone needs more details on this, leave a comment here and I'll do my best to help.

Dynamically Creating Multiple TextViews in LinearLayout

I want to create multiple TextViews inside a LinearLayout.The following code builds successfully but gives a NullPointerException at the line root.addView(t[i]);
public class MainActivity extends ActionBarActivity {
TextView t[];
LinearLayout root;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
root=(LinearLayout)findViewById(R.id.master);
t=new TextView[10];
LinearLayout.LayoutParams dim=new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
for(int i=0;i<10;i++)
{
t[i]=new TextView(this);
t[i].setLayoutParams(dim);
t[i].setText("YOHOHO: "+i);
root.addView(t[i]);
}
setContentView(root);
}
This really has no aim Iam just trying to learn things!

It's giving NPE because you are not setting your activity layout properly.
Do this
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.whereLinearLayoutMasterIs); // Add your layout here
root=(LinearLayout)findViewById(R.id.master);
t=new TextView[10];
LinearLayout.LayoutParams dim=new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
for(int i=0;i<10;i++)
{
t[i]=new TextView(this);
t[i].setLayoutParams(dim);
t[i].setText("YOHOHO: "+i);
root.addView(t[i]);
}
}
NOTER.layout.whereLinearLayoutMasterIs is indicative, use your layout in which R.id.master is

The problem is that root is null - this is because you've not yet set your Activity's content view via setContentView.
You need to do something like this:
super.onCreate(...);
setContentView(R.layout.yourLayoutName);
root=(LinearLayout)findViewById(R.id.master);

Adding a new edit text in list view on a button click in android

Is it possible to add a new EditText automatically in a ListView on a Button click?
If so please let me know.

EditText name = new EditText(youractivity);
convertView.addView(name);
Call notifydatasetchanged() but you have to save the field that you add becouse after scrolling into the list you will have in all list that editText and you have to remove where you don't want to appear.
What I recommand you is to make an editext into your cellView hidden and make it visible when you tap on your button.

You could make a custom adapter for your listview and give it a layout containing the edittext with the visibility set to gone. You can then set it to visible onbuttonclick.

I would like to suggest one code its not about listview but see if it could give you some idea,by adding views dynamically in linear layout which is inside scroll view.
public class MainActivity extends Activity {
ScrollView scrollview;
LinearLayout linearLayout;
LinearLayout.LayoutParams layoutParams;
static int i;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
scrollview = (ScrollView)findViewById(R.id.scrollview);
linearLayout = (LinearLayout)findViewById(R.id.linearlayout);
Button button = (Button)findViewById(R.id.button);
layoutParams = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
button.setOnClickListener(new OnClickListener(){
public void onClick(View v) {
TextView view = new TextView(MainActivity.this);
view.setText(++i+" view");
linearLayout.addView(view, layoutParams);
}
});
}}

Dynamically add element to layout

I am quite new to developing apps. Still I would have thought that this is a basic action, so if there is already a solved thread I would be OK with the link. But since I am searching for over 2 hours for this I am asking anyway:
I want to dynamically add an element to my layout every time the user clicks a button.
By now I have this:
XML (R.layout.game.xml)
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/submit_choice"
android:onClick="submitChoice"/>
</LinearLayout>
Java
public void submitChoice(View view)
{
TextView textView = new TextView(this);
textView.setTextSize(40);
textView.setText("text");
LinearLayout ll = new LinearLayout(this);
ll.addView(View.inflate(ll.getContext(), R.layout.game, null));
ll.addView(textView);
setContentView(ll);
}
Since the XML file does not change, it only works once.
So how can I add a second text when the user clicks the button a second time (without changing the XML file)? Examples are appreciated.

The problem comes from this line, that recreate the whole layout every time:
LinearLayout ll = new LinearLayout(this);
You should define it and setContentView(ll) outside the submitChoice function. Then on click only create and add the textView , then call ll.invalidate(); to see the changes.
Something like:
LinearLayout ll;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.game);
ll = (LinearLayout) findViewById(R.id.ll_game);
}
// More code...
public void submitChoice(View view) {
TextView textView = new TextView(this);
textView.setTextSize(40);
textView.setText("text");
ll.addView(textView);
ll.invalidate();
}
where ll_game is the id you have to set in xml for your LinearLayout.

Programmatically set a textview in Android

I currently have:
final TextView tv = new TextView(this);
final RelativeLayout rL = new RelativeLayout(this);
final EditText editText = (EditText)findViewById(R.id.editText);
final Button b1 = (Button)findViewById(R.id.b1);
b1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
rL.addView(tv);
tv.setText(editText.getText());
editText.setText("");
}
});
In my onCreate method but my textView does not show up on the screen when text is inputted and my button is pressed? Is there code to set where it is set up on the screen of my phone?

Here is your problem
final RelativeLayout rL = new RelativeLayout(this);
This RelativeLayout that contains the TextView is not even displayed on the screen, all you are doing is creating a RelativeLayout.
What you should do instead is add a RelativeLayout to your XML layout file (same one containing the EditText and Button and do the following
final RelativeLayout rL = (RelativeLayout)findViewById(R.id.myRelativeLayout);
...
rL.addView(tv);
Now since you are referencing an actual RelativeLayout, your text will be visible.
Hope I made some sort of sense.

Do you have a base layout? You're adding the EditText to the RelativeLayout, but you need to add the RelativeLayout to some already existing layout.
First, inflate some base layout. Then do a findViewById on that layout. Use this to call addView(editText);
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/base_layout"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
</RelativeLayout>
public class MyActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.layout);
RelativeLayout rl = (RelativeLayout)findViewById(R.layout.base_layout);
rl.addView(yourTextView);
}
}