Android - 将文本设置为 TextView

Question

I'm currently learning some android for a school project and I can't figure out the way to set text dynamically to a TextView .

Here is my code:

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_enviar_mensaje);
    err = (TextView)findViewById(R.id.texto);
    err.setText("Escriba su mensaje y luego seleccione el canal.");
}

This is currently not working and I can't find a way to make it work...

Any help will be much appreciated... Thank you for the time, José.

EDIT: Here is the activity_enviar_mensaje.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    ...
    tools:context=".EnviarMensaje" >
    ...
    <TextView
        android:id="@+id/texto"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/listaVista"
        android:layout_alignParentBottom="true"
        android:layout_alignRight="@+id/listaVista"
        android:text="TextView" />
    ...
</RelativeLayout>

By not working I mean the text shown does not change at any moment...

Answer 1

In your layout XML:

<TextView
        android:id="@+id/myAwesomeTextView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:text="Escriba el mensaje y luego clickee el canal a ser enviado"
        android:textSize="20sp" />

Then, in your activity class:

// globally 
TextView myAwesomeTextView = (TextView)findViewById(R.id.myAwesomeTextView);

//in your OnCreate() method
myAwesomeTextView.setText("My Awesome Text");

Answer 2

PUT THIS CODE IN YOUR XML FILE

<TextView
    android:id="@+id/textview1"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"/>

PUT THIS CODE IN YOUR JAVA FILE

// Declaring components like TextView globally is a good habit

TextView mTextView = (TextView) findViewById(R.id.textview1);

// Put this in OnCreate

mTextView.setText("Welcome to Dynamic TextView");

Answer 3

Well, @+id/listaVista ListView is drawn after @+id/texto and on top of it. So change in ListView from:

android:layout_below="@+id/editText1"

to:

android:layout_above="@+id/texto"

Also, since the list is drawn after textview, I find it dangerous to have android:layout_alignRight="@+id/listaVista" in TextView. So remove it and find another way of aligning.

EDIT Taking a second look at your layout I think this is what you really want to have:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".EnviarMensaje" >

    <TextView
        android:id="@+id/textView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:text="Escriba el mensaje y luego clickee el canal a ser enviado"
        android:textSize="20sp" />

    <EditText
        android:id="@+id/editText1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/textView1"
        android:layout_alignRight="@+id/textView1"
        android:layout_below="@+id/textView1"
        android:ems="10"
        android:inputType="text" />

    <TextView
        android:id="@+id/texto"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignLeft="@+id/listaVista"
        android:layout_alignParentBottom="true"
        android:text="TextView" />

    <ListView
        android:id="@+id/listaVista"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_above="@+id/texto"
        android:layout_alignParentLeft="true"
        android:layout_below="@+id/editText1" >
    </ListView>

</RelativeLayout>

Answer 4

In layout file.

<TextView
   android:id="@+id/myTextView"
   android:layout_width="match_parent"
   android:layout_height="wrap_content"
   android:text="Some Text"
   android:textSize="18sp"
   android:textColor="#000000"/>

In Activity

TextView myTextView = (TextView)findViewById(R.id.myTextView);
myTextView.setText("Hello World!");

Answer 5

In xml use this:

<TextView 
       android:id="@+id/textView"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"/>

In Activity define the view:

Textview textView=(TextView)findViewById(R.id.textView);
textView.setText(getResources().getString(R.string.txt_hello));

In string file:

<string name="txt_hello">Hello</string>

Output: Hello

Answer 6

I had a similar problem. It turns out I had two TextView objects with the same ID. They were in different view files and so Eclipse did not give me an error. Try to rename your id in the TextView and see if that does not fix your problem.

Answer 7

为什么不尝试将 textview 内容分配给 onStart() 而不是 onCreate()

Answer 8

in your activity_main.xml paste this code:

            <TextView
                 android:id="@+id/name"
                 android:layout_width="wrap_content"
                 android:layout_height="wrap_content"
                 android:layout_alignParentLeft="true"
                 android:layout_alignParentTop="true"
                 android:layout_marginLeft="19dp"
                 android:layout_marginTop="43dp"
                 android:text="@string/name" />

and go to res folder->values->strings.xml paste the below code with the code that already exists:

          <string name="name">Escriba su mensaje y luego seleccione el canal.</string>

the above code means that you have created a textview with id:name(android:id="@+id/name") and assigned that textview to a string with an identifier name(android:text="@string/name") in strings.xml your using that identifier name to assign the text,

Answer 9

Try This:

TextView err = (TextView)findViewById(R.id.text);

Ensure you import TextView.

Answer 10

这应该可以解决问题：

TextView.setText("test");

Answer 11

Please correct the following line:

err = (TextView)findViewById(R.id.texto);

to:

err = (TextView)findViewById(R.id.err);

Answer 12

In XML file,

<TextView
       android:id="@+id/textview"
       android:layout_width="wrap_content"
       android:layout_height="wrap_content"
       android:text="My Name"
       android:textColor="#cccccc"/>

In Java Activity file,

public class MainActivity1 extends Activity
 {
   TextView t1;
   public void onCreate(Bundle onSavedInstance)
      {
         setContentView(R.layout.xmlfilename);
          t1 = (TextView)findViewbyId(R.id.textview);
      }
 }

Answer 13

first your should create an object for text view TextView show_alter

show_alert = (TextView)findViewById(R.id.show_alert);
show_alert.setText("My Awesome Text");

Answer 14

You can set string in textview programatically like below.

TextView textView = (TextView)findViewById(R.id.texto);
err.setText("Escriba su mensaje y luego seleccione el canal.");

or

TextView textView = (TextView)findViewById(R.id.texto);
err.setText(getActivity().getResource().getString(R.string.seleccione_canal));

You can set string in xml like below.

<TextView
         android:id="@+id/name"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_alignParentLeft="true"
         android:layout_alignParentTop="true"
         android:layout_marginLeft="19dp"
         android:layout_marginTop="43dp"
         android:text="Escriba su mensaje y luego seleccione el canal." />

or

<TextView
         android:id="@+id/name"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_alignParentLeft="true"
         android:layout_alignParentTop="true"
         android:layout_marginLeft="19dp"
         android:layout_marginTop="43dp"
         android:text="@string/seleccione_canal" />

Answer 15

As you have given static text

err.setText("Escriba su mensaje y luego seleccione el canal.");

It will not change , it will remain same.

Example for Dynamic Text for textview is :

MainActivity.java
package com.example.dynamictextview;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends Activity {

    int count = 0;
    Button clickMeBtn;
    TextView dynamicText;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        clickMeBtn = (Button) findViewById(R.id.button_click);
        dynamicText = (TextView) findViewById(R.id.textview);

        clickMeBtn.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {

                count++;
                dynamicText.setText("dynamic text example : " + count);

            }
        });

    }

}

For activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.dynamictextview.MainActivity" >

    <Button 
        android:id="@+id/button_click"
       android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="click me"
        android:layout_centerInParent="true" />

    <TextView
        android:id="@+id/textview"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="@string/hello_world" 
        android:layout_below="@id/button_click"
        android:layout_centerHorizontal="true"
        android:textSize="25sp"
        android:layout_marginTop="20dp"
        />

</RelativeLayout>

Answer 16

You should use ButterKnife Library http://jakewharton.github.io/butterknife/

And use it like

@InjectView(R.id.texto)
TextView err;

in onCreate method

ButterKnife.inject(this)
err.setText("Escriba su mensaje y luego seleccione el canal.");

Answer 17

Your code is ok, you are loading the .xml that contains the TextView using setContentView() :

   setContentView(R.layout.activity_enviar_mensaje);

and then getting the reference of the TextView inside activity_enviar_mensaje.xml , and setting a text:

err = (TextView)findViewById(R.id.texto);
err.setText("Escriba su mensaje y luego seleccione el canal.");

The problem is that your TextView is hidden by the ListView :

Answer 18

I know its 2 months but yeah

replace your code

Private TextView err;
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_enviar_mensaje);
    err = (TextView)findViewById(R.id.texto);
    err.setText("Escriba su mensaje y luego seleccione el canal.");
}

Answer 19

In your layout. Your Texto should not contain (android:text=...). I would remove this line. Either keep the Java string OR the (android:text=...)

Answer 20

转到您的 activityMain 并通过从小部件部分添加小部件并通过选择和键入手动更改文本来设置文本。

Answer 21

final TextView err = (TextView)findViewById(R.id.texto);
err.setText("Escriba su mensaje y luego seleccione el canal.");

you can find every thing you need about textviewhere

Answer 22

In your layout XML you can insert

<TextView
        android:id="@+id/myAwesomeTextView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:text="Escriba el mensaje y luego clickee el canal a ser enviado"
        android:textSize="20sp"/>

Then, in your activity class

//globally 
TextView myAwesomeTextView = (TextView)findViewById(R.id.myAwesomeTextView);

//in your OnCreate() method
myAwesomeTextView.setText("My Awesome Text");

Answer 23

Kotlin Solution

To set using a String, just use this

view.text = "My string"

To do the same with a resource value, add this extension property to much more easily set your text

view.textRes = R.string.my_string

var TextView.textRes
    get() = 0 // HACK: property requires getter
    set(@StringRes textRes) {
        text = resources.getText(textRes)
    }

Answer 24

也许您已经在 onResume() 函数中分配了文本

Answer 25

It is so easy to add dynamic text in TextView. There is setText method in android with the help of this method you can set dynamic text for example..

textView.setText("Hello World");

for complete explanation you can visit this link. https://www.owlbuddy.com/learn/TextView-In-Android