I have two activities and the first is generating properly however the second is not. only the first element in the xml file will show up. here is my xml file:
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/alternateActivity"
android:shadowColor="#color/shadowColor"></TextView>
<Button
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="#+id/oldActivityButton"
android:text="#string/oldActivityButton"></Button>
<Button
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="#+id/changeText"
android:text="#string/changeTextButton"></Button>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/originalText"
android:id="#+id/textToChange"></TextView>
</LinearLayout>
and here is my activity that corresponds:
package fsg.dev.activitytest;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
public class newActivity extends Activity {
private Button oldActivityButton;
private Button changeText;
private TextView textToChange;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.alternate);
oldActivityButton = (Button) findViewById(R.id.oldActivityButton);
changeText = (Button) findViewById(R.id.changeText);
textToChange = (TextView) findViewById(R.id.textToChange);
oldActivityButton.setOnClickListener(new OnClickListener(){
public void onClick(View view){
changeActivity();
}
});
changeText.setOnClickListener(new OnClickListener(){
public void onClick(View view){
changeText();
}
});
}
private void changeActivity(){
Intent i = new Intent(this, activityTest.class);
startActivity(i);
}
private void changeText(){
if(textToChange.equals(R.string.originalText)){
textToChange.setText(R.string.newText);
} else {
textToChange.setText(R.string.originalText);
}
}
}
has anyone else seen this problem? or know of a way to fix it?
Try to add android:orientation="vertical" to your LinearLayout
replace
Intent i = new Intent(this, activityTest.class);
by
Intent i = new Intent().setClass(this, activityTest.class);
Related
I tried to display User Input from my main activity to my second activity, but when I typed in and click the send button on the main activity the whole app just crashes. Please help!
crash solved! Thanks a lot!
However, I can't get the message to display on the second activity.
MainActivity.java
package com.example.dell_inspiron.sendmessage;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import static android.R.id.message;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final String message = getResources().getString(R.string.UserInput);
final Button send = (Button) findViewById(R.id.send);
send.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v) {
Intent sendMessage = new Intent(MainActivity.this, DisplayMessageActivity.class);
sendMessage.putExtra("UserInput", message);
startActivity(sendMessage);
}
});
}
}
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
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="com.example.dell_inspiron.sendmessage.MainActivity">
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="textPersonName"
android:text="#string/edit"
android:ems="10"
android:layout_below="#+id/textView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="15dp"
android:id="#+id/UserInput" />
<Button
android:text="#string/send"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/UserInput"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="14dp"
android:id="#+id/send"
android:onClick="sendMessage" />
<TextView
android:text="#string/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/textView"
android:textSize="18sp"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
</RelativeLayout>
DisplayMessageActivity.java
package com.example.dell_inspiron.sendmessage;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class DisplayMessageActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_display_message);
Intent Extra = getIntent();
String textView = Extra.getStringExtra("UserInput");
TextView UserInput = (TextView) findViewById(R.id.UserOutput);
UserInput.setText(textView);
final Button button = (Button) findViewById(R.id.button2);
button.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v) {
launchActivity();
}
});
}
private void launchActivity() {
Intent intent = new Intent(this, MainActivity.class);
startActivity(intent);
}
}
activity_display_message.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/activity_display_message"
android:layout_width="match_parent"
android:layout_height="match_parent"
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="com.example.dell_inspiron.sendmessage.DisplayMessageActivity">
<Button
android:text="#string/Button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="51dp"
android:id="#+id/button2" />
<TextView
android:text="#string/UserOutput"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="91dp"
android:id="#+id/UserOutput" />
<TextView
android:text="#string/enter"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:id="#+id/enter"
android:textSize="18sp"
android:textColor="#android:color/holo_purple" />
</RelativeLayout>
You are passing int, but receive it in String, so your app crashed.
MainActivity
int message = R.string.UserInput;
Intent sendMessage = new Intent(MainActivity.this, DisplayMessageActivity.class);
sendMessage.putExtra("UserInput", message);
DisplayMessageActivity
Bundle Extra = getIntent().getExtras();
String textView = Extra.getString("UserInput");
You should also add
intent.putExtra("UserInput", message);
into launchActivity method.
Solution 1
Change String textView = Extra.getString("UserInput"); to int textView= Extra.getIntExtra("UserInput", 0);
Solution 2
To send the message to your second Activity, you need to use intent inside your MainActivity button click. Modify your code as below.
package com.example.dell_inspiron.sendmessage;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import static android.R.id.message;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
String message = getResources().getString(R.string.UserInput);
final Button send = (Button) findViewById(R.id.send);
send.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v) {
Intent sendMessage = new Intent(MainActivity.this,DisplayMessageActivity.class);
sendMessage.putExtra("UserInput", message);
startActivity(sendMessage);
}
});
}
}
Solution 3
This line look wrong to me
final String message = getResources().getString(R.string.UserInput);
If you want to get the editText string, this is the way to go
EditText input = (EditText)findViewById(R.id.UserInput); // declare your editText
final String message = input.getText().toString(); // get your input type
You mentioned that you are getting the user input from the MainActivity but i don't see anything like that in your code but you can do the below to pass some value from one activity to another...
Change your second activity like this
Bundle Extra = getIntent().getExtras();
String textView = Extra.getString("UserInput");
to
Intent Extra = getIntent();
String textView = Extra.getStringExtra("UserInput");
and change your MainActivity like this
int message = R.string.UserInput;
to
String message= getResources().getString(R.string.UserInput);
and
final Button send = (Button) findViewById(R.id.send);
send.setOnClickListener(new View.OnClickListener(){
public void onClick(View v) {
launchActivity();
}
});
to
Button send = (Button) findViewById(R.id.send);
send.setOnClickListener(new View.OnClickListener(){
public void onClick(View v) {
startActivity(sendMessage);
}
});
There is issue with your second Activity.You are passing int value in Intents but trying to get String value.
Change it as below:
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.TextView;
public class DisplayMessageActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_display_message);
Bundle Extra = getIntent().getExtras();
int textView = Extra.getInt("UserInput");
TextView UserInput = (TextView) findViewById(R.id.UserInput2);
UserInput.setText(textView);
final Button button = (Button) findViewById(R.id.button2);
button.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v) {
launchActivity();
}
});
}
private void launchActivity() {
Intent intent = new Intent(this, MainActivity.class);
startActivity(intent);
}
}
The code worked fine in other layout, but in others not..
layout XML:
<Button
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="register"
android:id="#+id/welcome_register"
android:background="#android:color/holo_green_dark"
android:textColor="#ffffff"
android:textSize="25sp"
android:onClick="register_Click" />
Activity:
package il.co.smartchip.hobby;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
public class LoginActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
getSupportActionBar().hide();
}
public void start_login(View view) {
//TODO log in
}
public void register_Click(View view) {
Intent intent = new Intent(this, RegisterActivity.class);
startActivity(intent);
}
I tried several things without success. Do you have any idea why it does not work?
In your case you need Intent i = new Intent(LoginActivity.this, RegisterActivity.class);.
LoginActivity.this points to the instance of the Activity you are currently in and you using it when you work with dynamic inner class like in your case.
this is for your current Object.
Im not so good teacher, hope you understand it.
Delete onclick on xml
<Button
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="register"
android:id="#+id/welcome_register"
android:background="#android:color/holo_green_dark"
android:textColor="#ffffff"
android:textSize="25sp"
/>
Init your button like that
package il.co.smartchip.hobby;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
public class LoginActivity extends AppCompatActivity {
private Button myButton;
private Activity thisActivity=this;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
getSupportActionBar().hide();
myButton=(Button)findViewById(R.id.welcome_register);
myButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(thisActivity, RegisterActivity.class);
startActivity(intent);
}
});
}}
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<EditText
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="#+id/speed"
android:inputType="number"></EditText>"
<TextView
android:id="#+id/TextViewSpeed"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text ="Speed"
android:layout_below="#+id/speed"
/>
<Button
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom"
android:text="AddValue"
android:id="#+id/AddValue"
>
</Button>
<ListView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="#+id/ListView"
android:layout_below="#+id/AddValue"
>
</ListView>
</RelativeLayout>
This is my layout code. I wanted to add a text data from EditText to the ListView which is on same page. How to write a code to add text to the list when I click on the AddValue Button.
Thanks in advance.
use this code
addbutton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
String val = edittext.getText().toString();
list.add(val);
((ArrayAdapter<Object>) listView.getAdapter()).notifyDataSetChanged();
}
});
Below snippet wil help you.
package org.sample;
import android.app.ListActivity;
import android.os.Bundle;
import android.view.ContextMenu;
import android.view.ContextMenu.ContextMenuInfo;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
public class SampleActivity extends Activity
{
private Button add;
private EditText speedText;
private ArrayAdapter<String> adapter;
private ListView AddValue;
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1);
AddValue=(ListView)findViewById(R.id.AddValue);
AddValue.setAdapter(adapter);
add = (Button) findViewById(R.id.add);
speedText = (EditText) findViewById(R.id.speed);
add.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View arg0)
{
if (speedText.getText().toString().length() != 0)
{
adapter.add(speedText.getText().toString());
adapter.notifyDataSetChanged();
}
}
});
}
}
I have a small app that when button presses navigates when moving from main screen to next screen this works fine, but when I added a button on the next page (to go back) it breaks.
Fun.java
package com.forcetechnology.OptusApp;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class Fun extends Activity {
OnClickListener backListener;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fun);
Button backButtonf = (Button)findViewById(com.forcetechnology.OptusApp.R.id.backtoMainf);
backListener = new OnClickListener()
{
public void onClick(View v)
{
Intent i = new Intent();
i.setClassName("com.forcetechnology.OptusApp", "com.forcetechnology.OptusApp.OptusAppMain");
startActivity(i);
}
};
backButtonf.setOnClickListener(backListener);
}
}
Fun.Xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ImageButton
android:id="#+id/backtoMainf"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/val5" />
</LinearLayout>
Main.xml
<ImageButton
android:id="#+id/funbutton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true"
android:background="#drawable/val5"
android:src="#drawable/val5" />
<ImageButton
android:id="#+id/executionbutton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="#+id/funbutton"
android:layout_alignParentRight="true"
android:background="#drawable/val2"
android:src="#drawable/val2" />
<ImageButton
android:id="#+id/performancebutton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/executionbutton"
android:layout_toLeftOf="#+id/funbutton"
android:background="#drawable/val3"
android:src="#drawable/val4" />
<ImageButton
android:id="#+id/innovationbutton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBottom="#+id/executionbutton"
android:layout_alignParentLeft="true"
android:background="#drawable/val3"
android:src="#drawable/val3" />
<ImageButton
android:id="#+id/peoplebutton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="#+id/innovationbutton"
android:layout_toLeftOf="#+id/executionbutton"
android:background="#drawable/val1"
android:src="#drawable/val1" />
</RelativeLayout>
OPtusAppMain.java
package com.forcetechnology.OptusApp;
import android.R;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageButton;
import android.widget.TextView;
import android.widget.Toast;
public class OptusAppMain extends Activity
{
OnClickListener funListener,executionListener,innovationListener,peopleListener,performanceListener;;
TextView testView;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(com.forcetechnology.OptusApp.R.layout.main);
ImageButton funButton = (ImageButton)findViewById(com.forcetechnology.OptusApp.R.id.funbutton);
ImageButton executionButton = (ImageButton)findViewById(com.forcetechnology.OptusApp.R.id.executionbutton);
ImageButton innovationButton = (ImageButton)findViewById(com.forcetechnology.OptusApp.R.id.innovationbutton);
ImageButton peopleButton = (ImageButton)findViewById(com.forcetechnology.OptusApp.R.id.peoplebutton);
ImageButton performanceButton = (ImageButton)findViewById(com.forcetechnology.OptusApp.R.id.performancebutton);
funListener = new OnClickListener()
{
public void onClick(View v)
{
Intent i = new Intent();
i.setClassName("com.forcetechnology.OptusApp", "com.forcetechnology.OptusApp.Fun");
startActivity(i);
}
};
executionListener = new OnClickListener()
{
public void onClick(View v)
{
Intent i = new Intent();
i.setClassName("com.forcetechnology.OptusApp", "com.forcetechnology.OptusApp.Execution");
startActivity(i);
}
};
innovationListener = new OnClickListener()
{
public void onClick(View v)
{
Intent i = new Intent();
i.setClassName("com.forcetechnology.OptusApp", "com.forcetechnology.OptusApp.Innovation");
startActivity(i);
}
};
peopleListener = new OnClickListener()
{
public void onClick(View v)
{
Intent i = new Intent();
i.setClassName("com.forcetechnology.OptusApp", "com.forcetechnology.OptusApp.People");
startActivity(i);
}
};
performanceListener = new OnClickListener()
{
public void onClick(View v)
{
Intent i = new Intent();
i.setClassName("com.forcetechnology.OptusApp", "com.forcetechnology.OptusApp.Performance");
startActivity(i);
}
};
funButton.setOnClickListener(funListener);
executionButton.setOnClickListener(executionListener);
innovationButton.setOnClickListener(innovationListener);
peopleButton.setOnClickListener(peopleListener);
performanceButton.setOnClickListener(performanceListener);
}
}
Edit: I have traced the error to this line Button backButtonf = (Button)findViewById(com.forcetechnology.OptusApp.R.id.backtoMainf); in fun.java.
In the onClick() of backListener, just call finish() to go back to the previous activity.
Lets take an example: You have two activities "A" & "B", You start your "B" activity from "A" that means your "A" activity is in stack so there is no need to start it again, just finish your "B" activity with "finish()" method.
public class A extends Activity{
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
public void onAbuttonClick()
{
startActivity(new Intent(A.this,B.class));
}
}
}
public class B extends Activity
{
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.second);
}
public onBbuttonclick(View v)
{
finish();
}
}
}
I'm very new to Android development and just started to study.
What I'm trying is to add a button and when that button is pressed a text "my first project" to get displayed in the text view.
With the help of some experts I created the button and text view.
So the button is showing in the simulator but when I click that button nothing happens.
Can anyone please help me with how can I display the text when pressing the button?
.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/txtView"
android:layout_width="150dp"
android:layout_height="150dp"
android:text="#string/hello" />
<Button
android:id="#+id/mybtn"
android:layout_width="50dp"
android:layout_height="30dp" />
<TextView
android:id="#+id/viewwidth"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<TextView
android:id="#+id/viewheight"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
</LinearLayout>
.java
import android.app.Activity;
import android.os.Bundle;
import android.widget.Button;
import android.widget.TextView;
import android.view.View;
import android.widget.Toast;
public class NameonbuttonclickActivity extends Activity implements View.OnClickListener {
Button mybtn;
TextView txtView;
String hello;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
setContentView(R.layout.main);
super.onCreate(savedInstanceState);
mybtn= new Button(this);
txtView=new TextView(this);
mybtn.setOnClickListener(this);
printmyname();
mybtn = (Button)findViewById(R.id.mybtn);
txtView=(TextView)findViewById(R.id.txtView);
txtView = (TextView)findViewById(R.id.viewwidth);
txtView = (TextView)findViewById(R.id.viewheight);
hello="This is my first project";
//setContentView(mybtn);
// setContentView(R.layout.main);
}
public void onClick(View view){
txtView.setText(hello);
//printmyname();
Toast.makeText(NameonbuttonclickActivity.this, hello, Toast.LENGTH_LONG).show();
}
private void printmyname(){
System.out.println("coming");
}
}
You can do like this:
String hello;
public void onCreate(Bundle savedInstanceState) {
setContentView(R.layout.main);
super.onCreate(savedInstanceState);
mybtn = (Button)findViewById(R.id.mybtn);
txtView=(TextView)findViewById(R.id.txtView);
txtwidth = (TextView)findViewById(R.id.viewwidth);
hello="This is my first project";
mybtn.setOnClickListener(this);
}
public void onClick(View view){
txtView.setText(hello);
}
Check your textview names. Both are same . You must use different object names and you have mentioned that textview object which is not available in your xml layout file.
Hope this will help you.
First create xml file as follows. Create one textview and a button:
main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/hello" />
<Button
android:id="#+id/mybutton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Click Me" />
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
</LinearLayout>
The first TextView is created by default. You can leave or remove it if you want.
Next one is to create a button
The next one is TextView where you want to display text.
Now coming to the main activity code...
package com.android.example.simple;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
public class SimpleActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
final TextView textView=(TextView)findViewById(R.id.textView1);
final Button button1 = (Button)findViewById(R.id.mybutton);
//Implement listener for your button so that when you click the
//button, android will listen to it.
button1.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// Perform action on click
textView.setText("You clicked the button");
} });
}
}
This is because you DON'T associated the OnClickListener() on the button retrieve from the XML layout.
You don't need to create object because they are already created by the Android system when you inflate XML file (with the Activity.setContentLayout( int resourceLayoutId ) method).
Just retrieve them with the findViewById(...) method.
Just check your code in .java class
You had written below line
mybtn.setOnClickListener(this);
before initializing the mybtn object I mean
mybtn = (Button)findViewById(R.id.mybtn);
just switch this two line or put that line "mybtn.setOnClickListener(this)" after initializing your mybtn object and you will get the answer what you want..
Try this
public void onClick(View view){
txtView.setText("hello");
//printmyname();
Toast.makeText(NameonbuttonclickActivity.this, "hello", Toast.LENGTH_LONG).show();
}
Also in toast use "Hello"
you use this as txtView.setText("hello");
MainActivity.java:
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.Button;
import android.widget.ImageButton;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import android.view.View;
import android.view.View.OnClickListener;
public class MainActivity extends Activity {
Button button1;
TextView textView1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button1=(Button)findViewById(R.id.button1);
textView1=(TextView)findViewById(R.id.textView1);
button1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
textView1.setText("TextView displayed Successfully");
}
});
}
}
activity_main.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"
android:orientation="vertical" >
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Click here" />
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
/>
</LinearLayout>
public void onCreate(Bundle savedInstanceState)
{
setContentView(R.layout.main);
super.onCreate(savedInstanceState);
mybtn = (Button)findViewById(R.id.mybtn);
txtView=(TextView)findViewById(R.id.txtView);
mybtn .setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
txtView.SetText("Your Message");
}
});
}
Check this:
hello.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View paramView) {
text.setText("hello");
}
});