I am a newbie to Android development. I have two Java files in my project. One file contains my main activity so I want to transfer the data from one Java file to another which contains the main activity.
cordovaExample.java:
package org.apache.cordova.example;
import android.content.Context;
import android.content.Intent;
import android.telephony.*;
import android.app.Activity;
import android.os.Bundle;
import android.widget.Toast;
import org.apache.cordova.*;
public class cordovaExample extends DroidGap
{
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
super.loadUrl("file:///android_asset/www/index.html");
Bundle extras = getIntent().getExtras();
String phno = extras.getString("novel.PhoneNumber");
Toast.makeText(getApplicationContext(),phno,Toast.LENGTH_LONG).show();
}
}
novel.java
package org.apache.cordova.example;
import android.content.Context;
import android.content.Intent;
import android.telephony.*;
import android.app.Activity;
import android.os.Bundle;
import android.widget.Toast;
public class novel extends Activity
{
public String PhoneNumber;
Context mcontext;
public String getNumber()
{
TelephonyManager tMgr=(TelephonyManager)mcontext.getSystemService(Context.TELEPHONY_SERVICE);
Intent intent = new Intent(this, cordovaExample.class);
intent.putExtra("novel.PhoneNumber", PhoneNumber);
startActivity(intent);
return PhoneNumber = tMgr.getLine1Number();
}
}
So i want to transfer the "PhoneNumber" from novel.java to cordovaExample.java but in novel.java, After running the application i am getting "unfortunately app has stopped" in emulator.
this is the logcat
08-12 15:49:37.657: E/AndroidRuntime(779): FATAL EXCEPTION: main
08-12 15:49:37.657: E/AndroidRuntime(779): java.lang.RuntimeException: Unable to start activity ComponentInfo{org.apache.cordova.example/org.apache.cordova.example.cordovaExample}: java.lang.NullPointerException
08-12 15:49:37.657: E/AndroidRuntime(779): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1956)
08-12 15:49:37.657: E/AndroidRuntime(779): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1981)
08-12 15:49:37.657: E/AndroidRuntime(779): at android.app.ActivityThread.access$600(ActivityThread.java:123)
08-12 15:49:37.657: E/AndroidRuntime(779): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1147)
08-12 15:49:37.657: E/AndroidRuntime(779): at android.os.Handler.dispatchMessage(Handler.java:99)
08-12 15:49:37.657: E/AndroidRuntime(779): at android.os.Looper.loop(Looper.java:137)
08-12 15:49:37.657: E/AndroidRuntime(779): at android.app.ActivityThread.main(ActivityThread.java:4424)
08-12 15:49:37.657: E/AndroidRuntime(779): at java.lang.reflect.Method.invokeNative(Native Method)
08-12 15:49:37.657: E/AndroidRuntime(779): at java.lang.reflect.Method.invoke(Method.java:511)
08-12 15:49:37.657: E/AndroidRuntime(779): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
08-12 15:49:37.657: E/AndroidRuntime(779): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
08-12 15:49:37.657: E/AndroidRuntime(779): at dalvik.system.NativeStart.main(Native Method)
08-12 15:49:37.657: E/AndroidRuntime(779): Caused by: java.lang.NullPointerException
08-12 15:49:37.657: E/AndroidRuntime(779): at org.apache.cordova.example.cordovaExample.onCreate(cordovaExample.java:20)
08-12 15:49:37.657: E/AndroidRuntime(779): at android.app.Activity.performCreate(Activity.java:4465)
08-12 15:49:37.657: E/AndroidRuntime(779): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1049)
08-12 15:49:37.657: E/AndroidRuntime(779): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1920)
08-12 15:49:37.657: E/AndroidRuntime(779): ... 11 more
Also, if I try the simple program I get the same result:
cordovaExample.java
package org.apache.cordova.example;
import android.content.Context;
import android.content.Intent;
import android.telephony.*;
import android.app.Activity;
import android.os.Bundle;
import android.widget.Toast;
import org.apache.cordova.*;
public class cordovaExample extends DroidGap
{
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
super.loadUrl("file:///android_asset/www/index.html");
novel c=new novel()
int a=c.getNumber();
Toast.makeText(getApplicationContext(),a,Toast.LENGTH_LONG).show();
}
}
novel.java
package org.apache.cordova.example;
import android.content.Context;
import android.content.Intent;
import android.telephony.*;
import android.app.Activity;
import android.os.Bundle;
import android.widget.Toast;
public class novel extends Activity
{
public int a=0;
public int getNumber()
{
a=5;
return a;
}
}
How can I resolve this?
you are using intent statement after return block
return PhoneNumber = tMgr.getLine1Number();
Intent myIntent = new Intent(novel.this, cordovaExample.class);
After return block any code show unreachable error .
After passing intent parameter then you can call return.
TelephonyManager tMgr=(TelephonyManager)mcontext.getSystemService(Context.TELEPHONY_SERVICE);
Intent intent = new Intent(this, cordovaExample.class);
intent.putExtra("novel.PhoneNumber", PhoneNumber);
startActivity(intent);
return PhoneNumber = tMgr.getLine1Number();
Android API guide contains a definitive FAQ item about how to pass data between between Activities/Services within a single application.
try this,
do like this in novel to set the phone number
Intent myIntent = new Intent(novel.this, cordovaExample.class);
myIntent.putExtra("phone", 989898989);
startActivity(myIntent);
in cordovaExample file do following to get the phoneNumber
Bundle b = this.getIntent().getExtras();
String i = b.getString("phone");
if you are not able to pass the data then alternative way is to declare public method and pass them, see following example,
novel.java
private static String phoneNumber = "";
public void onCreate()
{
...
phoneNumber = "9898989898";
...
}
public static String getPhoneNumber()
{
return phoneNumber;
}
cordovaExample.java
private static String phoneNumber = "";
phoneNumber = novel.getPhoneNumber();
Change your code to this : You got NPE in cordovaExample.java becaus in novel you put null PhoneNumber in Extra.
TelephonyManager tMgr=(TelephonyManager)mcontext.getSystemService(Context.TELEPHONY_SERVICE);
Intent intent = new Intent(this, cordovaExample.class);
PhoneNumber = tMgr.getLine1Number(); // Check PhoneNumber not null here before send to cordovaExample
if (PhoneNumber !=null ){
intent.putExtra("novel.PhoneNumber", PhoneNumber);
startActivity(intent);}
}
Related
i made a small method to check whether defined folder has files with a specific extension or not. I m getting null point exception on run.pls help to find mistake.method is checking .mp4 files and returning true if found and message is displayed.
Here is Code:
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;
import java.io.File;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
TextView filecheck;
filecheck = (TextView) findViewById(R.id.filecheck);
filecheck.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (accept()) {
Toast.makeText(MainActivity.this, "Files Found", Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(MainActivity.this, "Files Not Found", Toast.LENGTH_SHORT).show();
}
}
});
}
public boolean accept() {
final File pathname = new File("/sdcard/test/");
String files[] = pathname.list();
System.out.println(files.length);
for (String s : files) {
if (s.contains(".mp4")) {
System.out.println(s);
return true;
}
return false;
}
return false;
}
}
Here is exception:
E/AndroidRuntime: FATAL EXCEPTION: main
Process: jss.testmethods, PID: 23659
java.lang.NullPointerException
at jss.testmethods.MainActivity.accept(MainActivity.java:38)
at jss.testmethods.MainActivity$1.onClick(MainActivity.java:24)
at android.view.View.performClick(View.java:4478)
at android.view.View$PerformClick.run(View.java:18698)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:149)
at android.app.ActivityThread.main(ActivityThread.java:5257)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:609)
at dalvik.system.NativeStart.main(Native Method)
i was expecting simple error, i missed to add permission for read storage. it is working now.
I have a problem connected with reading a file in Java Application. Please help me as I'm trying to do it for four days and my CS teacher is not into Android Apps. Also any of the tutorials read does not help me.
I have a following app:
package com.bachosz.billionaires;
import android.support.v7.app.ActionBarActivity;
import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.util.StringTokenizer;
import android.content.ContextWrapper;
import android.content.res.AssetFileDescriptor;
import android.content.res.AssetManager;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivityBillionaires extends ActionBarActivity {
private int currentQuestion;
private String [] answers;
private Button answerButton;
private Button questionButton;
private TextView questionView;
private TextView answerView;
private EditText answerText;
private Question [] questions;
private Button buttonA;
private Button buttonB;
private Button buttonC;
private Button buttonD;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main_activity_billionaires);
try {
init();
} catch (IOException e) {
e.printStackTrace();
}
}
public void init() throws IOException
{
questions = new Question[2];
currentQuestion = 0;
InputStream inputStream = getResources().openRawResource(R.raw.questionstable);
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
String line = null;
String content,a,b,c,d,correct;
int id, x = 0;
StringTokenizer st = null;
while ((line=reader.readLine()) != null)
{
st= new StringTokenizer(line, ",");
id = Integer.parseInt(st.nextToken());
content = st.nextToken();
a = st.nextToken();
b = st.nextToken();
c = st.nextToken();
d = st.nextToken();
correct = st.nextToken();
questions[x] = new Question(id, content, a, b, c, d, correct);
x++;
}
reader.close();
answerButton = (Button)findViewById(R.id.AnswerButton);
questionButton = (Button)findViewById(R.id.QuestionButton);
questionView = (TextView)findViewById(R.id.QuestionTextView);
answerView = (TextView) findViewById(R.id.AnswerTextView);
answerText = (EditText) findViewById(R.id.AnswerText);
buttonA = (Button)findViewById(R.id.buttonA);
buttonB = (Button)findViewById(R.id.buttonB);
buttonC = (Button)findViewById(R.id.buttonC);
buttonD = (Button)findViewById(R.id.buttonD);
answerButton.setOnClickListener(new OnClickListener()
{
public void onClick(View v) {
checkAnswer();
}});
questionButton.setOnClickListener(new OnClickListener(){
#Override
public void onClick(View v) {
showQuestion();
}});
}
public void showQuestion()
{
// if(currentQuestion == questions.length)
// currentQuestion =0;
questionView.setText(questions[0].toString());
answerView.setText("");
answerText.setText("");
currentQuestion++;
}
public boolean isCorrect(String answer)
{
return (answer.equalsIgnoreCase(questions[currentQuestion].getCorrect()));
}
public void checkRight()
{
// String right
}
public void checkAnswer()
{
String answer = questions[currentQuestion].getCorrect();
if(isCorrect(answer))
answerView.setText("You're right!");
else
answerView.setText("Sorry, the correct answer is "+answers[currentQuestion]);
}
#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_activity_billionaires, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
It is taken from Java application I was writing previously (that is why so many comments). How I can access the fileName in Android App? I was trying InputStream, get Assets, etc. but It does not work or I am doing it improperly. Currently it is throwing NullPointerException.
LOG CAT:
10-09 13:38:37.663: E/Trace(921): error opening trace file: No such file or directory (2)
10-09 13:38:39.354: D/AndroidRuntime(921): Shutting down VM
10-09 13:38:39.354: W/dalvikvm(921): threadid=1: thread exiting with uncaught exception (group=0x40a13300)
10-09 13:38:39.384: E/AndroidRuntime(921): FATAL EXCEPTION: main
10-09 13:38:39.384: E/AndroidRuntime(921): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.bachosz.billionaires/com.bachosz.billionaires.MainActivityBillionaires}: java.lang.NullPointerException
10-09 13:38:39.384: E/AndroidRuntime(921): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059)
10-09 13:38:39.384: E/AndroidRuntime(921): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
10-09 13:38:39.384: E/AndroidRuntime(921): at android.app.ActivityThread.access$600(ActivityThread.java:130)
10-09 13:38:39.384: E/AndroidRuntime(921): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
10-09 13:38:39.384: E/AndroidRuntime(921): at android.os.Handler.dispatchMessage(Handler.java:99)
10-09 13:38:39.384: E/AndroidRuntime(921): at android.os.Looper.loop(Looper.java:137)
10-09 13:38:39.384: E/AndroidRuntime(921): at android.app.ActivityThread.main(ActivityThread.java:4745)
10-09 13:38:39.384: E/AndroidRuntime(921): at java.lang.reflect.Method.invokeNative(Native Method)
10-09 13:38:39.384: E/AndroidRuntime(921): at java.lang.reflect.Method.invoke(Method.java:511)
10-09 13:38:39.384: E/AndroidRuntime(921): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
10-09 13:38:39.384: E/AndroidRuntime(921): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
10-09 13:38:39.384: E/AndroidRuntime(921): at dalvik.system.NativeStart.main(Native Method)
10-09 13:38:39.384: E/AndroidRuntime(921): Caused by: java.lang.NullPointerException
10-09 13:38:39.384: E/AndroidRuntime(921): at com.bachosz.billionaires.MainActivityBillionaires.readFile(MainActivityBillionaires.java:111)
10-09 13:38:39.384: E/AndroidRuntime(921): at com.bachosz.billionaires.MainActivityBillionaires.init(MainActivityBillionaires.java:140)
10-09 13:38:39.384: E/AndroidRuntime(921): at com.bachosz.billionaires.MainActivityBillionaires.onCreate(MainActivityBillionaires.java:70)
10-09 13:38:39.384: E/AndroidRuntime(921): at android.app.Activity.performCreate(Activity.java:5008)
10-09 13:38:39.384: E/AndroidRuntime(921): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079)
10-09 13:38:39.384: E/AndroidRuntime(921): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023)
10-09 13:38:39.384: E/AndroidRuntime(921): ... 11 more
The error says you're getting a NPE (Null Pointer Exception) at com.bachosz.billionaires.MainActivityBillionaires. You need to look at the code section that you use to call that activity. (it is not in your code above - or else we don't know which line with the given information)
Another thing you have to make sure is that you have the appropriate context.
AssetManager assetManage = appContext.getAssets();
String[] filelist = assetManage.list("");
First you should clean up your code, at least to show it here where we don't know what are you doing.
It's easier to understand.
Why are you using assets? In Android the most common way to access resources is the .../res/raw folder.
It makes a reference of the file in the autogenerated R.class so you can access it anywhere.
Make sure your filename is lowercase and has no spaces. If you haven't raw folder under res, create it manually.
Try this:
InputStream inputStream = getResources().openRawResource(R.raw.YOURFILE);
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
String line = reader.readLine();
while (line != null)
{
// Read file.
}
Firstly: copy YOURFILE to assets folder.
Then, AssetManager assetManage = getAssets();
Then,
InputStream myInput = null;
try {
myInput = assetManager.open("YOURFILE");
} catch (IOException e1) {
e1.printStackTrace();
}
And finally BufferedReader reader = new BufferedReader(new InputStreamReader(myInput));
follow the above code step by step.
Hello i am trying to load images from a server into a gallery but always keep giving me this error:
04-28 00:54:47.596: W/dalvikvm(715): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
04-28 00:54:47.608: E/AndroidRuntime(715): FATAL EXCEPTION: main
04-28 00:54:47.608: E/AndroidRuntime(715): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.plateamobile/com.plateamobile.ProdDetails}: java.lang.NullPointerException
04-28 00:54:47.608: E/AndroidRuntime(715): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.app.ActivityThread.access$2300(ActivityThread.java:125)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.os.Handler.dispatchMessage(Handler.java:99)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.os.Looper.loop(Looper.java:123)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.app.ActivityThread.main(ActivityThread.java:4627)
04-28 00:54:47.608: E/AndroidRuntime(715): at java.lang.reflect.Method.invokeNative(Native Method)
04-28 00:54:47.608: E/AndroidRuntime(715): at java.lang.reflect.Method.invoke(Method.java:521)
04-28 00:54:47.608: E/AndroidRuntime(715): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
04-28 00:54:47.608: E/AndroidRuntime(715): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
04-28 00:54:47.608: E/AndroidRuntime(715): at dalvik.system.NativeStart.main(Native Method)
04-28 00:54:47.608: E/AndroidRuntime(715): Caused by: java.lang.NullPointerException
04-28 00:54:47.608: E/AndroidRuntime(715): at com.plateamobile.ProdDetails.set_info(ProdDetails.java:138)
04-28 00:54:47.608: E/AndroidRuntime(715): at com.plateamobile.ProdDetails.onCreate(ProdDetails.java:49)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
04-28 00:54:47.608: E/AndroidRuntime(715): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
04-28 00:54:47.608: E/AndroidRuntime(715): ... 11 more
This is my code:
package com.plateamobile;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.util.ArrayList;
import java.util.List;
import org.ksoap2.SoapEnvelope;
import org.ksoap2.serialization.PropertyInfo;
import org.ksoap2.serialization.SoapObject;
import org.ksoap2.serialization.SoapPrimitive;
import org.ksoap2.serialization.SoapSerializationEnvelope;
import org.ksoap2.transport.HttpTransportSE;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.View;
import android.view.ViewGroup;
import android.widget.*;
import android.widget.Gallery.LayoutParams;
public class ProdDetails extends Activity {
private ImageSwitcher mSwitcher;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.prod_details);
Bundle extras = getIntent().getExtras();
((TextView)findViewById(R.id.prod_name)).setText(extras.getString("name"));
((TextView)findViewById(R.id.price_prod)).setText(new general().formatNumb(extras.getString("price")));
set_info();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.prod_details, menu);
return true;
}
public void set_info(){
ObjConexion object = new ObjConexion();
SoapObject request = new SoapObject(object.NameSpace(), "getProdinfo");
SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
Bundle extras = getIntent().getExtras();
PropertyInfo idPro =new PropertyInfo();
idPro.setName("id");
idPro.setValue(extras.getString("id"));
idPro.setType(String.class);
request.addProperty(idPro);
envelope.setOutputSoapObject(request);
HttpTransportSE androidHttpTransport = new HttpTransportSE(object.Url());
androidHttpTransport.debug = true;
try {
androidHttpTransport.call("getProdinfo", envelope);
List<SoapPrimitive> response = (List<SoapPrimitive>) envelope.getResponse();
((TextView)findViewById(R.id.commerce)).setText(response.get(0).toString());
((TextView)findViewById(R.id.description)).setContentDescription(response.get(1).toString());
}catch (Exception e) {
e.printStackTrace();
Toast.makeText(this,e.getMessage().toString(),Toast.LENGTH_LONG).show();
}
request = new SoapObject(object.NameSpace(), "getProdImg");
envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
idPro =new PropertyInfo();
idPro.setName("id");
idPro.setValue(extras.getString("id"));
idPro.setType(Integer.class);
request.addProperty(idPro);
envelope.setOutputSoapObject(request);
androidHttpTransport = new HttpTransportSE(object.Url());
androidHttpTransport.debug = true;
ArrayList<SoapObject> imagesList = new ArrayList<SoapObject>();
try {
androidHttpTransport.call("getProdImg", envelope);
List<SoapObject> response = (List<SoapObject>) envelope.getResponse();
for (int cont=0; cont<response.size() ;cont++){
SoapObject responseChild = (SoapObject) response.get(cont);
imagesList.add(responseChild);
}
}catch (Exception e) {
e.printStackTrace();
if (e.getMessage() == null){
Toast.makeText(this,"Error en la conexion",Toast.LENGTH_LONG).show();
}else{
Toast.makeText(this,e.getMessage().toString(),Toast.LENGTH_LONG).show();
}
}
Gallery _gallery_ = (Gallery) findViewById(R.id.images_prod);
if (imagesList!=null){
_gallery_.setAdapter(new ImageAdapter(getApplicationContext(), imagesList));
}else{
Log.e("DEBUGTAG", "Remtoe Image Exception");
}
}
public void goBack(View v){
Intent intent = new Intent(ProdDetails.this, main_win.class);
startActivity(intent);
}
public class ImageAdapter extends BaseAdapter {
/** The parent context */
private Context myContext;
/** URL-Strings to some remote images. */
private ArrayList<SoapObject> pckg_data;
/** Simple Constructor saving the 'parent' context. */
public ImageAdapter(Context c, ArrayList<SoapObject> data) {
this.myContext = c;
this.pckg_data = data;
}
/** Returns the amount of images we have defined. */
public int getCount() { return this.pckg_data.size(); }
/* Use the array-Positions as unique IDs */
public Object getItem(int position) { return position; }
public long getItemId(int position) { return position; }
/** Returns a new ImageView to
* be displayed, depending on
* the position passed. */
public View getView(int position, View convertView, ViewGroup parent) {
ImageView i = new ImageView(this.myContext);
try {
/* Open a new URL and get the InputStream to load data from it. */
URL aURL = new URL(pckg_data.get(position).getPropertyAsString(1));
URLConnection conn = aURL.openConnection();
conn.connect();
InputStream is = conn.getInputStream();
/* Buffered is always good for a performance plus. */
BufferedInputStream bis = new BufferedInputStream(is);
/* Decode url-data to a bitmap. */
Bitmap bm = BitmapFactory.decodeStream(bis);
bis.close();
is.close();
/* Apply the Bitmap to the ImageView that will be returned. */
i.setImageBitmap(bm);
} catch (IOException e) {
Log.e("DEBUGTAG", "Remtoe Image Exception", e);
}
/* Image should be scaled as width/height are set. */
i.setScaleType(ImageView.ScaleType.FIT_CENTER);
/* Set the Width/Height of the ImageView. */
i.setLayoutParams(new Gallery.LayoutParams(150, 150));
return i;
}
/** Returns the size (0.0f to 1.0f) of the views
* depending on the 'offset' to the center. */
public float getScale(boolean focused, int offset) {
/* Formula: 1 / (2 ^ offset) */
return Math.max(0, 1.0f / (float)Math.pow(2, Math.abs(offset)));
}
}
}
The first time your app is created there is no intent calling it. So Bundle extras = getIntent().getExtras(); causes the NullPointerException.
Enclose the statement in a try block.
try
{
Bundle extras = getIntent().getExtras();
}
catch(Exception E){
//do nothing
}
But this isn't the right way to do it.
If this activity is going to be called again, I suggest you use onNewIntent() method and make this activity singleTop.
http://developer.android.com/reference/android/app/Activity.html
http://developer.android.com/guide/topics/manifest/activity-element.html
I am doing an android app and i was thinking of creating a theme option. Well all I was thinking of doing was to allow the user to click on a image button which represented a theme. And when he clicks on it I start a new activity i.e i direct him to the home page. Also i have created a few integer variables which are set to 1 when the user clicks on a button.
Then in the other classes all i do is check if the variables are 1 or not and depending on that i apply the theme. By theme i mean i just change the background wallpaper. But this is not working. I mean the code works but if use an if loop to check the variable values and then apply the effects it causes an error.
Here's the complete code:
package com.example.themetest;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageButton;
import android.widget.LinearLayout;
public class MainActivity extends Activity implements OnClickListener{
ImageButton ib1;
ImageButton ib2;
int water=0;
int fire=0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ib1 = (ImageButton) findViewById(R.id.imageButton1);
ib2 = (ImageButton) findViewById(R.id.imageButton2);
ib1.setOnClickListener(this);
ib2.setOnClickListener(this);
}
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch(v.getId()){
case R.id.imageButton1:
water = 1;
Intent wi = new Intent("com.example.themetest.THEME");
startActivity(wi);
break;
case R.id.imageButton2:
fire = 1;
Intent fi = new Intent("com.example.themetest.THEME");
startActivity(fi);
break;
}
}
}
Here's the other class where i check which variable is set to 1 and apply the effect.
package com.example.themetest;
import java.io.InputStream;
import android.app.Activity;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.widget.EditText;
import android.widget.LinearLayout;
public class Theme extends Activity{
MainActivity main;
Resources res;
Drawable drawable;
LinearLayout linearLayout;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.theme);
if(main.water==1){
res = getResources();
drawable = res.getDrawable(R.drawable.water_theme);
linearLayout = (LinearLayout)findViewById(R.id.ll);
linearLayout.setBackgroundDrawable(drawable);
}
else if(main.fire==1){
res = getResources();
drawable = res.getDrawable(R.drawable.fire_theme);
linearLayout = (LinearLayout)findViewById(R.id.ll);
linearLayout.setBackgroundDrawable(drawable);
}
else{
res = getResources();
drawable = res.getDrawable(R.drawable.ic_launcher);
linearLayout = (LinearLayout)findViewById(R.id.ll);
linearLayout.setBackgroundDrawable(drawable);
}
}
}
I can change the wallpaper without using the if loop, but i want to do it this way which is not working. Can anyone please tell me why?
Log cat:
01-15 12:08:23.339: D/dalvikvm(273): GC_EXTERNAL_ALLOC freed 767 objects / 55936 bytes in 235ms
01-15 12:08:25.539: D/AndroidRuntime(273): Shutting down VM
01-15 12:08:25.539: W/dalvikvm(273): threadid=1: thread exiting with uncaught exception (group=0x4001d800)
01-15 12:08:25.559: E/AndroidRuntime(273): FATAL EXCEPTION: main
01-15 12:08:25.559: E/AndroidRuntime(273): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.themetest/com.example.themetest.Theme}: java.lang.NullPointerException
01-15 12:08:25.559: E/AndroidRuntime(273): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
01-15 12:08:25.559: E/AndroidRuntime(273): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
01-15 12:08:25.559: E/AndroidRuntime(273): at android.app.ActivityThread.access$2300(ActivityThread.java:125)
01-15 12:08:25.559: E/AndroidRuntime(273): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
01-15 12:08:25.559: E/AndroidRuntime(273): at android.os.Handler.dispatchMessage(Handler.java:99)
01-15 12:08:25.559: E/AndroidRuntime(273): at android.os.Looper.loop(Looper.java:123)
01-15 12:08:25.559: E/AndroidRuntime(273): at android.app.ActivityThread.main(ActivityThread.java:4627)
01-15 12:08:25.559: E/AndroidRuntime(273): at java.lang.reflect.Method.invokeNative(Native Method)
01-15 12:08:25.559: E/AndroidRuntime(273): at java.lang.reflect.Method.invoke(Method.java:521)
01-15 12:08:25.559: E/AndroidRuntime(273): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
01-15 12:08:25.559: E/AndroidRuntime(273): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
01-15 12:08:25.559: E/AndroidRuntime(273): at dalvik.system.NativeStart.main(Native Method)
01-15 12:08:25.559: E/AndroidRuntime(273): Caused by: java.lang.NullPointerException
01-15 12:08:25.559: E/AndroidRuntime(273): at com.example.themetest.Theme.onCreate(Theme.java:29)
01-15 12:08:25.559: E/AndroidRuntime(273): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
01-15 12:08:25.559: E/AndroidRuntime(273): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
01-15 12:08:25.559: E/AndroidRuntime(273): ... 11 more
01-15 12:08:31.089: I/Process(273): Sending signal. PID: 273 SIG: 9
I think the better way to do this is pass the name or code of the theme user selected along with the intent.
This might help: Passing data through Intent and receiving it
You cannot access other activities variables this way, a better way (for example) is to use a constant class..
public class Constants {
public static int water=0;
public staticint fire=0;
}
MainActivity:
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch(v.getId()){
case R.id.imageButton1:
Constants.water = 1;
Intent wi = new Intent("com.example.themetest.THEME");
startActivity(wi);
break;
case R.id.imageButton2:
Constants.fire = 1;
Intent fi = new Intent("com.example.themetest.THEME");
startActivity(fi);
break;
}
}
Theme:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.theme);
if(Constants.water==1){
res = getResources();
drawable = res.getDrawable(R.drawable.water_theme);
linearLayout = (LinearLayout)findViewById(R.id.ll);
linearLayout.setBackgroundDrawable(drawable);
}
else if(Constants.fire==1){
res = getResources();
drawable = res.getDrawable(R.drawable.fire_theme);
linearLayout = (LinearLayout)findViewById(R.id.ll);
linearLayout.setBackgroundDrawable(drawable);
}
else{
res = getResources();
drawable = res.getDrawable(R.drawable.ic_launcher);
linearLayout = (LinearLayout)findViewById(R.id.ll);
linearLayout.setBackgroundDrawable(drawable);
}
}
I'm trying to write a speech to text app for android. Now the app doesn't crash on the emulator, but when I upload it to a samsung galaxy s 1900 I get following error messages in eclipse:
11-05 17:43:48.814: I/dalvikvm(3092): Could not find method com.example.speechtotext.MainActivity.getActionBar, referenced from method com.example.speechtotext.MainActivity.onCreate
11-05 17:43:48.818: W/dalvikvm(3092): VFY: unable to resolve virtual method 3036: Lcom/example/speechtotext/MainActivity;.getActionBar ()Landroid/app/ActionBar;
11-05 17:43:48.818: D/dalvikvm(3092): VFY: replacing opcode 0x6e at 0x0009
11-05 17:43:48.818: D/dalvikvm(3092): VFY: dead code 0x000c-0061 in Lcom/example/speechtotext/MainActivity;.onCreate (Landroid/os/Bundle;)V
11-05 17:43:48.896: D/AndroidRuntime(3092): Shutting down VM
11-05 17:43:48.900: W/dalvikvm(3092): threadid=1: thread exiting with uncaught exception (group=0x4001d7d0)
11-05 17:43:48.900: E/AndroidRuntime(3092): FATAL EXCEPTION: main
11-05 17:43:48.900: E/AndroidRuntime(3092): java.lang.NoSuchMethodError: com.example.speechtotext.MainActivity.getActionBar
11-05 17:43:48.900: E/AndroidRuntime(3092): at com.example.speechtotext.MainActivity.onCreate(MainActivity.java:40)
11-05 17:43:48.900: E/AndroidRuntime(3092): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
11-05 17:43:48.900: E/AndroidRuntime(3092): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
11-05 17:43:48.900: E/AndroidRuntime(3092): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
11-05 17:43:48.900: E/AndroidRuntime(3092): at android.app.ActivityThread.access$2300(ActivityThread.java:125)
11-05 17:43:48.900: E/AndroidRuntime(3092): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
11-05 17:43:48.900: E/AndroidRuntime(3092): at android.os.Handler.dispatchMessage(Handler.java:99)
11-05 17:43:48.900: E/AndroidRuntime(3092): at android.os.Looper.loop(Looper.java:123)
11-05 17:43:48.900: E/AndroidRuntime(3092): at android.app.ActivityThread.main(ActivityThread.java:4627)
11-05 17:43:48.900: E/AndroidRuntime(3092): at java.lang.reflect.Method.invokeNative(Native Method)
11-05 17:43:48.900: E/AndroidRuntime(3092): at java.lang.reflect.Method.invoke(Method.java:521)
11-05 17:43:48.900: E/AndroidRuntime(3092): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:871)
11-05 17:43:48.900: E/AndroidRuntime(3092): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:629)
11-05 17:43:48.900: E/AndroidRuntime(3092): at dalvik.system.NativeStart.main(Native Method)
11-05 17:44:11.343: I/dalvikvm(3092): threadid=3: reacting to signal 3
11-05 17:44:12.724: E/dalvikvm(3092): Failed to write stack traces to /data/anr/traces.txt (805 of 2366): Unknown error: 0
11-05 17:44:22.165: I/Process(3092): Sending signal. PID: 3092 SIG: 9
firmware version 2.2 on the phone.
When running in emulator the program just sais that speech isn't supported in the emulator, no crash though.
This my code:
package com.example.speechtotext;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.MenuItem;
import android.support.v4.app.NavUtils;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;
import android.view.View;
import android.widget.EditText;
import android.speech.tts.TextToSpeech;
import android.speech.tts.TextToSpeech.OnInitListener;
import android.content.Intent;
import java.util.Locale;
import android.content.pm.PackageManager;
import android.content.pm.ResolveInfo;
import android.speech.RecognizerIntent;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends Activity implements OnClickListener,
OnInitListener {
private int MY_DATA_CHECK_CODE = 0;
private TextToSpeech myTTS;
private static final int VOICE_RECOGNITION_REQUEST_CODE = 1234;
private ListView mList;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getActionBar().setDisplayHomeAsUpEnabled(true);
Button speakButton = (Button) findViewById(R.id.speak);
speakButton.setOnClickListener(this);
Intent checkTTSIntent = new Intent();
checkTTSIntent.setAction(TextToSpeech.Engine.ACTION_CHECK_TTS_DATA);
startActivityForResult(checkTTSIntent, MY_DATA_CHECK_CODE);
// Get display items for later interaction
Button speakButton2 = (Button) findViewById(R.id.btn_speak);
mList = (ListView) findViewById(R.id.list);
// Check to see if a recognition activity is present
PackageManager pm = getPackageManager();
List<ResolveInfo> activities = pm.queryIntentActivities(new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH), 0);
if (activities.size() != 0) {
speakButton2.setOnClickListener(this);
} else {
speakButton2.setEnabled(false);
speakButton2.setText("Recognizer not present");
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
NavUtils.navigateUpFromSameTask(this);
return true;
}
return super.onOptionsItemSelected(item);
}
// Indien men op de speakbutton klikt
public void onClick(View arg0) {
EditText enteredText = (EditText) findViewById(R.id.enter);
String words = enteredText.getText().toString();
speakWords(words);
if (arg0.getId() == R.id.btn_speak) {
startVoiceRecognitionActivity();
}
}
// Zorgt voor de spraak
private void speakWords(String speech) {
// myTTS.speak(speech, TextToSpeech.QUEUE_ADD, null); zorgt dat de app
// het toevoegt aan de queue zodat het wacht tot de vorige speech
// opdracht uitgesproken is
myTTS.speak(speech, TextToSpeech.QUEUE_FLUSH, null);
}
// Controleren of de data beschikbaar is
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == MY_DATA_CHECK_CODE) {
if (resultCode == TextToSpeech.Engine.CHECK_VOICE_DATA_PASS) {
myTTS = new TextToSpeech(this, this);
} else {
Intent installTTSIntent = new Intent();
installTTSIntent
.setAction(TextToSpeech.Engine.ACTION_INSTALL_TTS_DATA);
startActivity(installTTSIntent);
}
}
if (requestCode == VOICE_RECOGNITION_REQUEST_CODE
&& resultCode == RESULT_OK) {
// Fill the list view with the strings the recognizer thought it
// could have heard
ArrayList<String> matches = data
.getStringArrayListExtra(RecognizerIntent.EXTRA_RESULTS);
mList.setAdapter(new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, matches));
}
super.onActivityResult(requestCode, resultCode, data);
}
private void startVoiceRecognitionActivity() {
Intent intent = new Intent(RecognizerIntent.ACTION_RECOGNIZE_SPEECH);
intent.putExtra(RecognizerIntent.EXTRA_LANGUAGE_MODEL,
RecognizerIntent.LANGUAGE_MODEL_FREE_FORM);
intent.putExtra(RecognizerIntent.EXTRA_PROMPT,
"Speech recognition demo");
startActivityForResult(intent, VOICE_RECOGNITION_REQUEST_CODE);
}
// Taal juist zetten en indien er een fout is geeft men een foutboodschap
public void onInit(int initStatus) {
if (initStatus == TextToSpeech.SUCCESS) {
myTTS.setLanguage(Locale.US);
} else if (initStatus == TextToSpeech.ERROR) {
Toast.makeText(this, "Sorry! Text To Speech failed...",
Toast.LENGTH_LONG).show();
}
}
}
I've checked that the min API isn't to high, but eclipse has set that to 2.2 so I think thats fine.
Someone an idea what could be wrong or how to debug?
Kind regards,
The problem is that you are trying to use ActionBar on device running Android 2.2 (API level 8), but ActionBar was added in API level 11.
So you have basically two options here:
Don't use ActionBar in your app.
Use ActionBarSherlock library, it backports action bar back to Android 2.x (though you still need to make some minor changes in your code, read the docs of ActionBarSherlock for more details).