This is a my .java file:
package com.example.rohitkulkarni.readingfile;
import android.os.Environment;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ListView listView= (ListView) findViewById(R.id.listView);
try{
InputStream inputreader = getAssets().open("myaddress.txt");
BufferedReader buffreader = new BufferedReader(new InputStreamReader(inputreader));
ArrayList<String> lines = new ArrayList<String>();
boolean hasNextLine =true;
while (hasNextLine){
String line = buffreader.readLine();
lines.add(line);
hasNextLine = line != null;
}
tv.setText((CharSequence) lines);
//exception here:
ArrayAdapter<String> adapter = new ArrayAdapter<String>(getApplicationContext(),R.id.listView,lines);
listView.setAdapter(adapter);
inputreader.close();
}
catch(FileNotFoundException e){
}catch(IOException e){
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
This is my xml file:
<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" android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin" tools:context=".MainActivity">
<ListView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/listView"
android:layout_alignParentTop="true"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true" />
</RelativeLayout>
I am working with getAsset all working fine but only ArrayAdaptor is not working I tried all possible combinations but it is not working. It is working with simple string array.
String line = buffreader.readLine();
//i found that he was taking null value so checking for it
if(line != null);
lines.add(line);
hasNextLine = line != null;
//not it is working fine thanks
The middle argument is wrong, from here:
The resource ID for a layout file containing a TextView to use when instantiating views.
But you are passing an id:
new ArrayAdapter<String>(getApplicationContext(), R.id.listView, lines);
This should be a layout:
new ArrayAdapter<String>(getApplicationContext(), R.layout.???, lines);
try to use..
adapter = new ArrayAdapter<String>(getApplicationContext(), android.R.layout.simple_list_item_1 , lines);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(getApplicationContext(),R.id.listView,lines);
In this line you have passed a ListView id.
But the constructor expecting a Layout to inflate. So pass in a Layout.
Like this
ArrayAdapter<String> adapter = new ArrayAdapter<String>(getApplicationContext(),android.R.layout.simple_list_item_1,lines);
EDIT
Also in this line.
tv.setText((CharSequence) lines);
tv is not defined in your activity. And if its a TextView you are setting an ArrayList to it. try tv.setText(lines.toString())
Related
Hello,
I've already read a lot of responses on how to make maps work with lover than 11sdk, but i did everything and i still can't make it work. My minsdk is set to 8. I always get error like this:
Manifest merger failed : uses-sdk:minSdkVersion 8 cannot be smaller than version 9 declared in library com.google.android.gms:play-services:6.1.71`
I can't change my min sdk to 9 or 11, because i desperatedly need it to be 8. I already tryed changing to supportmapfragment and so on. Here's my code:
fragment_maps.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<fragment
android:id="#+id/mapView"
android:layout_width="match_parent"
android:layout_height="match_parent"
class="com.google.android.gms.maps.SupportMapFragment"/>
</RelativeLayout>
maps.java
package com.miesto.meniu;
import android.support.v4.app.FragmentActivity;
import android.support.v7.app.ActionBarActivity;
import android.support.v7.app.ActionBar;
import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import com.google.android.gms.maps.*;
import android.os.Build;
import com.google.android.gms.maps.SupportMapFragment;
import android.widget.Toast;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import java.text.SimpleDateFormat;
public class maps extends FragmentActivity {
Fragment fragment = getSupportFragmentManager().findFragmentById(
R.id.mapView);
SupportMapFragment mapFragment = (SupportMapFragment) fragment;
GoogleMap mMap = mapFragment.getMap();
#Override
protected void onCreate(Bundle savedInstanceState) {
createMapView();
addMarker();
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_maps);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment())
.commit();
}
}
GoogleMap googleMap;
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.maps, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_maps, container, false);
return rootView;
}
}
/**
* THIS WONT WORK SO I JUST COMMENTED IT BUT LEFT IT IF ILL NEED IT LATER
*/
private void createMapView(){
/**
* Catch the null pointer exception that
* may be thrown when initialising the map
try {
if(null == googleMap){
HERE I GET ERROR THAT getfragmentmanager and findfragmentbyid NEED minsdk 11
googleMap = ((MapFragment) getFragmentManager().findFragmentById(
R.id.mapView)).getMap();
if(null == googleMap) {
Toast.makeText(getApplicationContext(),
"Klaida rodant zemelapi", Toast.LENGTH_SHORT).show();
}
}
} catch (NullPointerException exception){
Log.e("miesto.meniu", exception.toString());
}
*/
}
/** -------------------------------
*
*/
/**
* Adds a marker to the map
*/
private void addMarker(){
/** Make sure that the map has been initialised **/
if(null != googleMap){
googleMap.addMarker(new MarkerOptions()
.position(new LatLng(0, 0))
.title("Marker")
.draggable(true)
);
}
}
}
any help would be greatly appreciated
google-play-services_lib manifest change android:minSdkVersion 8
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.google.android.gms"
android:versionCode="6171000"
android:versionName="6.1.71-000" >
<uses-sdk android:minSdkVersion="9" />
<application />
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I just starting learning to develop an android app and for that i followed google's basic tutorial.
In the tutorial there is simply a textbox and a button. On pressing the button it takes the text from the textbox and displays it in another activity. But somehow the button isn't working for me.
Here is the code for the fragment_main.xml, MainActivity.java and DisplayMessageActivity.java. I just want to know if i am doing something wrong or if i am missing something.
fragmant_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="horizontal">
<EditText android:id="#+id/edit_message"
android:layout_weight="1"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:hint="#string/edit_message" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/button_send"
onClick="sendMessage" />
</LinearLayout>
MainActivity.java:
package com.example.first;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.app.ActionBarActivity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
public class MainActivity extends ActionBarActivity {
public final static String EXTRA_MESSAGE = "com.example.myfirstapp.MESSAGE";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment()).commit();
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container,
false);
return rootView;
}
}
/** Called when the user clicks the Send button */
public void sendMessage(View view) {
Intent intent = new Intent(this, DisplayMessageActivity.class);
EditText editText = (EditText) findViewById(R.id.edit_message);
String message = editText.getText().toString();
intent.putExtra(EXTRA_MESSAGE, message);
startActivity(intent);
}
}
DisplayMessageActivity.java
package com.example.first;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.app.ActionBarActivity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
public class DisplayMessageActivity extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Get the message from the intent
Intent intent = getIntent();
String message = intent.getStringExtra(MainActivity.EXTRA_MESSAGE);
// Create the text view
TextView textView = new TextView(this);
textView.setTextSize(40);
textView.setText(message);
// Set the text view as the activity layout
setContentView(textView);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.display_message, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_display_message,
container, false);
return rootView;
}
}
}
EDIT **
In your fragment_main.xml file the the last line of your Button tag should be : android:onClick="sendMessage" instead of onClick="sendMessage"
I'm trying to make a chat bot using Program AB and AIML. I am trying to get the AIML files off the internet so the bot can read them and use them. I wrote some code saying to get a text file of a URL, but that gives me an unhandled exception, and yes, I added the internet permission in the Manifest. btw I am new to Java.
Here is the MainActivity.java
package com.NautGames.xecta.app;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.EditText;
import org.alicebot.ab.Chat;
import org.alicebot.ab.Bot;
import android.view.View;
import android.widget.Button;
import java.io.BufferedReader;
import java.net.MalformedURLException;
import java.io.InputStreamReader;
import java.net.URL;
import java.io.IOException;
public class MainActivity extends ActionBarActivity {
//private EditText botIn = (EditText) findViewById(R.id.botInput);;
//private Button botSubmit = (Button) findViewById(R.id.tellBot);;
//String botString = botIn.getText().toString();
EditText mEdit;
public String botIn;
private String readData()
{
try
{
// Create a URL for the desired page
URL url = new URL("https://www.dropbox.com/sh/9cyfz0b45mj6szr/7pBuupNz3N");
// Read all the text returned by the server
BufferedReader in = new BufferedReader(new InputStreamReader(url.openStream()));
String str;
while ((str = in.readLine()) != null)
{
// str is one line of text; readLine() strips the newline character(s)
}
in.close();
}
catch (MalformedURLException e)
{
//do nothing
}
catch (IOException e)
{
//do nothing
}
return "URL";
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void buttonOnClick(View v)
{
Button button=(Button) v;
mEdit = (EditText)findViewById(R.id.editText1);
//Creating bot
String botname="xecta";
String path= readData();
Bot xecta = new Bot(botname, path);
Chat chatSession = new Chat(xecta);
String request = mEdit.getText().toString();
String response = chatSession.multisentenceRespond(request);
((Button) v).setText(response);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
Heres my 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"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin"
tools:context="com.NautGames.chatbot.app.MainActivity"
android:background="#drawable/oneiric640x960">
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/editText1"
android:hint="Talk to Xecta"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Send"
android:id="#+id/button1"
android:layout_centerHorizontal="true"
android:layout_below="#+id/editText1"
android:onClick="buttonOnClick" />
</RelativeLayout>
I dont want to have to make the user download all the AIML files because it takes up too much.
Any help will be greatly appreciated.
The dropbox link you are using is dropbox's Online file viewer, which to java looks like a bunch of HTML code, and it has no clue what to do with it. Goto the dropbox link you specified, and hit Download (upright) > Download as Zip, and use that URL instead. But you will have to modify your bot to first extract all the files from .zip format, and then you should be good to go.
BTW the URL is https://dl.dropboxusercontent.com/shz/9cyfz0b45mj6szr/7pBuupNz3N/xecta?token_hash=AAEs9cDFswt98D1IhLnab4dHwhwh5z2Lmhq_N6H-2M0LWg&top_level_offset=6
"I dont want to have to make the user download all the AIML files because it takes up too much. Any help will be greatly appreciated." -- If you have to download each file when you want to use them, it would slow down your App extremely. It would be much easier to download all of it first and save it into a local cache so they don't have to download it again later. FYI The download is less than half a megabyte in zip form, so it shouldn't be bad to download it all.
I'm trying to build an text view that goes to onClick but its not working they told me to add this code I did it but I'm having a lot of errors in it.
this is my MainActivity.java
package imamalsajadsayings.android.com;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.TextView;
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void runNextTask(){
final View addView = getLayoutInflater().inflate(R.layout.addnewtracker, null);
final TrackerInfo newInfo = new TrackerInfo();
//set up for model selection
TextView modelTextview = (TextView)addView.findViewById(R.id.state1);
modelTextview.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
and is my textview
<TextView
android:id="#+id/state1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/Tracker_model"
android:clickable="true"
note : I don't have addnewtracker created
errors :
Description Resource Path Location Type
TrackerInfo cannot be resolved to a type MainActivity.java /ImamAlsajadsayings/src/imamalsajadsayings/android/com line 20 Java Problem
addnewtracker cannot be resolved or is not a field MainActivity.java /ImamAlsajadsayings/src/imamalsajadsayings/android/com line 19 Java Problem
The method setOnClickListener(View.OnClickListener) in the type View is not applicable for the arguments (new OnClickListener(){}) MainActivity.java /ImamAlsajadsayings/src/imamalsajadsayings/android/com line 23 Java Problem
TrackerInfo cannot be resolved to a type MainActivity.java /ImamAlsajadsayings/src/imamalsajadsayings/android/com line 20 Java Problem
The method onClick(View) of type new OnClickListener(){} must override or implement a supertype method MainActivity.java /ImamAlsajadsayings/src/imamalsajadsayings/android/com line 25 Java Problem
OnClickListener cannot be resolved to a type MainActivity.java /ImamAlsajadsayings/src/imamalsajadsayings/android/com line 23 Java Problem
add to activity:
public void modelTextViewClick(View v) {
//do something on click
}
and to layout:
<TextView android:id="#+id/state1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/Tracker_model"
android:clickable="true"
android:onClick="modelTextViewClick"/>
and remove your on click listener.
Change below code to your XML file
<TextView android:id="#+id/state1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/Tracker_model"
android:clickable="true"
android:onClick="runNextTask"/>
and just modify your java file as follow.
public void runNextTask(View v){
final View addView = getLayoutInflater().inflate(R.layout.addnewtracker, null);
final TrackerInfo newInfo = new TrackerInfo();
//set up for model selection
TextView modelTextview = (TextView)addView.findViewById(R.id.state1);
modelTextview.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
}
});
you need to import this package to avoid this error
missing this -> import android.view.View.OnClickListener;
Use below piece of code.
package imamalsajadsayings.android.com;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.TextView;
public class MainActivity extends Activity {
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void runNextTask(){
final View addView = getLayoutInflater().inflate(R.layout.addnewtracker, null);
final TrackerInfo newInfo = new TrackerInfo();
//set up for model selection
TextView modelTextview = (TextView)addView.findViewById(R.id.state1);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public void modelTextViewClick(View view)
{
// here view reference is your text view reference.
// put your on click handler code.
}
}
difference between this code and your code is onclick handler. In xml you have already defined a on click handler which you have to use in activity code. Other way set onclick listener handler foe your widget. Your doing both but either one of them is allowed not both for any widget in android.
You haven't call runNextTask from ur onCreate()
u r inflating a layout but didn't add that layout in any layout of ur activity_main layout using addView method
thats why it didn't work
it should be
package imamalsajadsayings.android.com;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.TextView;
import android.view.View.OnClickListener;
public class MainActivity extends Activity {
private LayoutInflater inflater;
private LinearLayout someLayout;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
someLayout = (LinearLayout) findViewById(R.id.some_layout); //layout present in activity_main
inflater = (LayoutInflater)getSystemService(LAYOUT_INFLATER_SERVICE);
runNextTask();
}
public void runNextTask(){
LinearLayout mInflatedLayout = (LinearLayout) inflater.inflate(R.layout.addnewtracker, null);
final TrackerInfo newInfo = new TrackerInfo();
//set up for model selection
TextView modelTextview = (TextView)mInflatedLayout.findViewById(R.id.state1);
someLayout.addView(mInflatedLayout);
modelTextview.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
Assuming u r using LinearLayout in ur activity_main layout
i have checked everything in this but still i am getting a null pointer exception . whenever i am trying to change the properties of button in java file, app stop working and logcat showing null pointer exception. plzz help me out
here is my code
package com.example.rapid_finger;
import java.util.Random;
import android.annotation.SuppressLint;
import android.annotation.TargetApi;
import android.app.Activity;
import android.os.Build;
import android.os.Bundle;
import android.support.v4.app.NavUtils;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;
public class PlayScreen extends Activity {
#SuppressLint("NewApi")
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Random rand = new Random();
int data = rand.nextInt(99);
String str = Integer.toString(data);
Button b = (Button) findViewById(R.id.b1);
b.setText(str);
setContentView(R.layout.activity_play_screen);
// Show the Up button in the action bar.
setupActionBar();
}
/**
* Set up the {#link android.app.ActionBar}, if the API is available.
*/
#TargetApi(Build.VERSION_CODES.HONEYCOMB)
private void setupActionBar() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
getActionBar().setDisplayHomeAsUpEnabled(true);
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.play_screen, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
// This ID represents the Home or Up button. In the case of this
// activity, the Up button is shown. Use NavUtils to allow users
// to navigate up one level in the application structure. For
// more details, see the Navigation pattern on Android Design:
//
// http://developer.android.com/design/patterns/navigation.html#up- vs-back
//
NavUtils.navigateUpFromSameTask(this);
return true;
}
return super.onOptionsItemSelected(item);
}
}
and here is my xml file
<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"
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=".PlayScreen" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/scores" />
<Button
android:id="#+id/b1"
android:background="#drawable/back"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</RelativeLayout>
You did findViewById before you setContentView.
setContentView should come first
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_play_screen);
Random rand = new Random();
int data = rand.nextInt(99);
String str = Integer.toString(data);
Button b = (Button) findViewById(R.id.b1);
b.setText(str);
// Show the Up button in the action bar.
setupActionBar();
}
put setContentView(R.layout.activity_play_screen); after super.onCreate(savedInstanceState);
// replace this code
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_play_screen);
Random rand = new Random();
int data = rand.nextInt(99);
String str = Integer.toString(data);
Button b = (Button) findViewById(R.id.b1);
b.setText(str);
// Show the Up button in the action bar.
setupActionBar();
}