Develop Reference

Xamarin: Setting text for a TextView programmatically

This is probably a mistake or lack of comprehension on my part, but I am quite confused right now. I'm trying to set a TextView in my Xamarin Android application programmatically. Here's my code:
TextView currentCharacterName =
FindViewById(Resource.Id.characterName);
currentCharacterName.SetText("test");
Unfortunately, this does not work, as I get the error "Argument 1: cannot convert from 'string' to 'int'". After reading in the available methods for SetText, I noticed the method I'm trying to call demands a ResId. I don't really understand why I would need a ResId to modify the text of a TextView.
I tried searching on Google for answers, and I came across this answer from 2014 that had the exact same problem as I do. The solution was to use the Text() method instead to set the TextView. Unfortunately, when I try this solution, I get the error "Non-invocable member 'TextView.Text' cannot be used like a method". When I try to check the Text method description, I see "string TextView {get/set} To be added."
Does this mean there's no implementation yet to set the text of a TextView? I am really reluctant to believe this, as it baffles me that such a big framework like Xamarin wouldn't even have get/set functions for something as simple as setting the text of TextView. I feel like there's a very simple solution for my problem, but I can't seem to find it.

TextView.SetText(X) allows you to set the text from a Resource id:
currentCharacterName.SetText(Resources.Id.MyString);
You are looking for the Text property:
currentCharacterName.Text = "test";
Xamarin: TextView class
Android.Widget.TextView.Text Property
Syntax:
public String Text { get; set; }

Test this code:
TextView currentCharacterName = FindViewById<TextView>(Resource.Id.characterName);
currentCharacterName.Text = "Your Text";

Change TextView text

I'm trying to change my TextView text from the code.
This is what my xml looks like:
XML:
<TextView
android:id="#+id/textView1"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical|center_horizontal" />
And the code:
TextView tv1 = (TextView)findViewById(R.id.textView1);
tv1.setText("Hello");
setContentView(tv1);
I'm getting an error on my device and the application stops.
I tried to show a TextView (not connected to an XML TextView) and it worked.

Your approach is incorrect. I think it will be Null Pointer Exception (next time post log cat)
You need to specify the layout you are using first, before finding views.
Java:
// Specify the layout you are using.
setContentView(R.layout.yourlayout);
// Load and use views afterwards
TextView tv1 = (TextView)findViewById(R.id.textView1);
tv1.setText("Hello");
Kotlin:
// Specify the layout you are using.
setContentView(R.layout.yourlayout)
// Load and use views afterwards
val tv1: TextView = findViewById(R.id.textView1)
tv1.text = "Hello"
Click Here to study exactly you want to know

remove this.. setContentView(tv1);

I got the same problem. My app was stopping too.
Actually, I was writing the code outside of the function/method. So to fix this problem, these lines
TextView tv1 = (TextView)findViewById(R.id.textView1);
tv1.setText("Hello");
must be inside a function/method. (can be user defined)
(I am new to android studio so I don't know the reason behind the problem but I only know how to fix this. Maybe this helps new ones despite this question being 8 years old.)

facing problem while displaying the value of the variable

I have just tried to display the value of the variable but is showing some kind of exception
that is FORCE CLOSE.
the code i have tried is
TextView myTextView = (TextView) findViewById(R.id.result9);
myTextView.setText("your score is " +count);
considered count=0 intially.
Can any one suggest me for this problem
thanks in advance

if myTexyView is in dialog you have to do this:
myTextView = (TextView) dialog.findViewById();
anyway do clean project...this happens sometimes:
in eclipse: project->clean->your project

Seems findViewById() returns null. It means that either there's no widget with id result9 in current layout or your forgot to setContentView().

can please check your xml which one you have set, setContainView() it mast have TextView with "result9" this id.

"Force Close" Error on declaring TextView and ToggleButton

Well basicly I have a textview and when the application is created it sets a string as the textviews text not hard, but I get a force close error when I run the app on my phone.
TextView sdcard=(TextView)findViewById(R.id.sd_textview);
sdcard.setText(R.string.not_mounted);
Then I have a error on a togglebutton also
ToggleButton silent=(ToggleButton)findViewById(R.id.silentbutton);
silent.setChecked(false);
And I have errors for all my other buttons/textviews can anyone help, please?!
EDIT:
I cant post pics because I am a new member, :(
Link to imgshack http://imageshack.us/photo/my-images/849/unledggp.png/
If code for the whole textview snippet.
if (android.os.Environment.getExternalStorageState().equals(android.os.Environment.MEDIA_UNMOUNTED)) {
TextView sdcard=(TextView)findViewById(R.id.sd_textview);
sdcard.setText(R.string.not_mounted);
}
OnCreate Function
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
checkSD();
checkRing();
checkWifi();
checkBt();
}

Look for all instances of sd_textview and make sure the one that you're trying to reference is a TextView. If you want more clarity you can debug your code and see what object is actually being returned by not casting into a TextView:
View sdcard = findViewById(R.id.sd_textview); //debug this
//you can also log the View object to see the type
Log.d("Test", "" + sdcard);

Looking at your error log (assuming its the right error log) you have a ClassCastException in the checkWifi method. Edit your question and include ALL of the onCreate method and all of the checkWifi method, but I expect you are using the same id for multiple views.

Two things I can think of (although seeing more code would help).
Make sure you have called setContentView(R.layout.main) (or whatever your layout file is called). Do this BEFORE any attempt to use findViewById(...).
Secondly sdcard.setText(R.string.not_mounted); in this statement R.string.not_mounted is a resource ID (int) and not a string. You would need to use...
sdcard.setText(getString(R.string.not_mounted));

Resource ID question

may I know is it possible I use the resource id but I didnt set the Content View in the activity?
for example: abc.xml have one TextView id = "R.id.Text". Can I use the use TextView name = (TextView)findViewById(R.id.Text); method in the activity which was setContentView(R.layout.def);?
P/S: sorry about my bad english, hope you guys understand what I'm talking about.
Thanks

Short answer: no. The code setContentView(R.layout.def); loads only the views from def.xml, not abc.xml. You have to use another method to create the TextView or include it in def.xml.
For another method to use for separate XML files, check out http://developerlife.com/tutorials/?p=303