I'm new to Android and I was practicing, when i finished this practice app i ran it but it says "unfortunately has stopped" where is the problem?My app looks like a simple log in screen and i don't think there's a problem with the XML file.
package com.mycompany.testbutton;
import android.media.Image;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class MainActivity extends ActionBarActivity {
Button buttonLog = (Button)findViewById(R.id.button1);
EditText userName = (EditText)findViewById(R.id.usernameText);
EditText passWord = (EditText)findViewById(R.id.passwordText);
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
buttonLog.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String username = String.valueOf(userName.getText());
String password = String.valueOf(passWord.getText());
String allTogetherToast = "Your Email is " + username + " and your Password is " + password;
Toast.makeText(MainActivity.this, allTogetherToast, Toast.LENGTH_LONG).show();
}
});
}
#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);
}
}
Initialize these
Button buttonLog = (Button)findViewById(R.id.button1);
EditText userName = (EditText)findViewById(R.id.usernameText);
EditText passWord = (EditText)findViewById(R.id.passwordText);
after your
setContentView(R.layout.activity_main)
so your code will be like this
package com.mycompany.testbutton;
import android.media.Image;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class MainActivity extends ActionBarActivity {
Button buttonLog;
EditText userName;
EditText passWord;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
buttonLog = (Button)findViewById(R.id.button1);
userName = (EditText)findViewById(R.id.usernameText);
passWord = (EditText)findViewById(R.id.passwordText);
buttonLog.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String username = String.valueOf(userName.getText());
String password = String.valueOf(passWord.getText());
String allTogetherToast = "Your Email is " + username + " and your Password is " + password;
Toast.makeText(MainActivity.this, allTogetherToast, Toast.LENGTH_LONG).show();
}
});
}
#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;
}
Move
Button buttonLog = (Button)findViewById(R.id.button1);
EditText userName = (EditText)findViewById(R.id.usernameText);
EditText passWord = (EditText)findViewById(R.id.passwordText);
after setContentView(....) inside onCreate(...)
Corrected:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button buttonLog = (Button)findViewById(R.id.button1);
EditText userName = (EditText)findViewById(R.id.usernameText);
EditText passWord = (EditText)findViewById(R.id.passwordText);
Views available only after setContentView(....)
Related
I am making an app in android Studio and if you open the app on your phone you see the Launcer activity. I have a button that sends you to a new activity where te game is located. Once i click the Start button, The app closes and doesn't goes to the other activity. Why is that?
This is my code of the Launcher activity:
package joenio.sirname;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
public class SirName_launcher extends AppCompatActivity {
public static Button button_start;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_sir_name_launcher);
StartButton();
}
public void StartButton(){
button_start = (Button) findViewById(R.id.button_start);
button_start.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent1 = new Intent("joenio.sirname.Game");
startActivity(intent1);
}
}
);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu_sir_name_launcher, 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);
}
}
And this is the code of the second activity:
package joenio.sirname;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import java.util.ArrayList;
import android.widget.Toast;
public class Game extends AppCompatActivity {
public static EditText editText_surname;
public static TextView textView_name;
public static Button button_check;
int x =0; //to keep track of qustions
//Context editText_this = this;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_game);
Displayquestions();
}
public void Displayquestions(){
final ArrayList<String> mQuestionList = new ArrayList<>();
mQuestionList.add("1+2");
mQuestionList.add("6+8");
mQuestionList.add("5 * 6");
mQuestionList.add("8*5");
mQuestionList.add("6+16");
mQuestionList.add("18-5");
textView_displayquestion.setText((mQuestionList.get(x)));//displayquestion is textview
final ArrayList<String> mAnswerList=new ArrayList<>();
mAnswerList.add("3");
mAnswerList.add("14");
mAnswerList.add("30");
mAnswerList.add("40");
mAnswerList.add("22");
mAnswerList.add("13");
//button_check is the button when user click it will first check answer and than move to next question if answer is correct
button_check.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v) {
//editText_this;
String answer = editText_ans.getText().toString();
if (answer.equals(mAnswerList.get(x))) {
x = x + 1;
textView_displayquestion.setText(mQuestionList.get(x)); //answer is correct display next quesion
Toast.makeText(getApplication().getBaseContext(),
(R.string.Nice), Toast.LENGTH_SHORT).show();
} else {
Toast.makeText(getApplication().getBaseContext(),
(R.string.tryagain), Toast.LENGTH_SHORT).show();
}
}
});
}
}
You are no where initializing your TextView and Button which must be causing NullPointerException.
Change your Game activity like this
TextView textView_displayquestion;
Button button_check;
EditText editText_ans;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_game);
textView_displayquestion = (TextView)findViewById(R.id.displayquestion); //change as per your id
button_check = (Button)findViewById(R.id.buttoncheck); //change as per your id
editText_ans = (EditText)findViewById(R.id.answer); //change as per your id
Displayquestions();
}
In your button click , change the code as below.
Intent intent1 = new Intent(SirName_launcher.this, Game.class);
startActivity(intent1);
And also add the new Game Activity in your Manifest file too.
enter code hereThis is my First Activity::> I need:
1) select an option
2) click send an image (from drawable) should go to the second activity but it does not only from 2nd to 1st works fine all my xml and manifest files are correct (I double checked)
package com.example.damianlopez.myassignment;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.ActionBar;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
Button toBob;
private ImageView burgerImage;
private RadioGroup radioGroupChoice;
private RadioButton radBurger;
private RadioButton radScare;
private RadioButton radSick;
private final int MY_SELECTION = 111;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
try {
setContentView(R.layout.activity_main);
//get radio Buttons
//radioGroupChoice = (RadioGroup) findViewById(R.id.radGroupChoice);
radBurger = (RadioButton)findViewById(R.id.radBurger);
radScare = (RadioButton)findViewById(R.id.radScare);
radSick = (RadioButton)findViewById(R.id.radSick);
//display app icon
ActionBar ab = getSupportActionBar();
ab.setDisplayShowHomeEnabled(true);
ab.setIcon(R.mipmap.ic_launcher);
//getting Intent
Intent getIntent = getIntent();
Bundle myBundle2 = getIntent.getExtras();
setResult(Activity.RESULT_OK, getIntent);
//
}catch(Exception e ){
}
}//End onCreate()
public void onClickButton(View v){
try {
//get radio gruop id's
radioGroupChoice = (RadioGroup) findViewById(R.id.radGroupChoice);
int mySelection = radioGroupChoice.getCheckedRadioButtonId();
if(radioGroupChoice.getCheckedRadioButtonId() == -1){
Toast.makeText(getApplicationContext(), "Please make a selection", Toast.LENGTH_LONG).show();
}else {
//creating new Intent
Intent msgToBob = new Intent(MainActivity.this, Main22Activity.class);
Bundle myBundle = new Bundle();
myBundle.putInt("imageChoice", mySelection);
msgToBob.putExtras(myBundle);
startActivityForResult(msgToBob, MY_SELECTION);
}
}catch(Exception e ){
}
}//End of onClick()
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent myData) {
super.onActivityResult(requestCode, resultCode, myData);
Log.i("OnActivityResult() call", "***********");
radioGroupChoice = (RadioGroup) findViewById(R.id.radGroupChoice);
int selected = radioGroupChoice.getCheckedRadioButtonId();
//get Images
burgerImage = (ImageView) findViewById(R.id.pumpkin_burger);
if(radioGroupChoice.getCheckedRadioButtonId() == -1){
Toast.makeText(getApplicationContext(), "Please make a selection", Toast.LENGTH_LONG).show();
}
else {
switch (requestCode) {
case MY_SELECTION: {
if (resultCode == Activity.RESULT_OK) {
if (radBurger.isChecked()) {
burgerImage.setImageResource(R.drawable.pumpkin_burger);
} else if (radScare.isChecked()) {
burgerImage.setImageResource(R.drawable.pumpkin_scared);
} else if (radSick.isChecked()) {
burgerImage.setImageResource(R.drawable.pumpkin_sick);
};
}
break;
}//end case
}//end switch
}//end else if
}
#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 Second Activity===>
package com.example.damianlopez.myassignment;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.ActionBar;
import android.support.v7.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.Toast;
public class Main22Activity extends AppCompatActivity {
private RadioGroup radioGroupChoice2;
private RadioButton radBurger;
private RadioButton radScare;
private RadioButton radSick;
private Button toAlice;
private ImageView currentImage;
private ImageView scareImage;
private ImageView sickImage;
private final int MY_SELECTION2 = 222;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main22);
//display app icon
ActionBar ab = getSupportActionBar();
ab.setDisplayShowHomeEnabled(true);
ab.setIcon(R.mipmap.ic_launcher);
//Buttons
radioGroupChoice2 = (RadioGroup)findViewById(R.id.radGroupChoice);
//toAlice = (Button) findViewById(R.id.sndToAlice);
//get the intent called
Intent myLocalIntent = getIntent();
Bundle myBundle = myLocalIntent.getExtras();
myLocalIntent.putExtras(myBundle);
setResult(Activity.RESULT_OK, myLocalIntent);
}
public void onClickButton2(View v){
try {
radioGroupChoice2 = (RadioGroup) findViewById(R.id.radGroupChoice);
if (radioGroupChoice2.getCheckedRadioButtonId() == -1) {
Toast.makeText(getApplicationContext(), "Please make a selection", Toast.LENGTH_LONG).show();
} else {
Intent myIntent2 = new Intent();
Bundle myBundle2 = new Bundle();
int myImage = radioGroupChoice2.getCheckedRadioButtonId();
myBundle2.putInt("selectedImage", myImage);
myIntent2.putExtras(myBundle2);
setResult(Activity.RESULT_OK, myIntent2);
}
}catch(Exception e) {
}
finish();
#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_main22, 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);
}
}
The Problem is, that the Text field which is in "Wizard2Activity" just shows "nothing" and not what the user has typed in the "EditText" in "Wizard1".
Wizard1.java:
package com.CENSORED.CENSORED;
import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
public class Wizard1 extends Activity {
public static final String PREFS ="examplePrefs";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_wizard1);
final EditText et = (EditText)findViewById(R.id.editText1);
Button nextAct = (Button)findViewById(R.id.button1);
nextAct.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v){
String message = et.getText().toString();
SharedPreferences examplePrefs = getSharedPreferences(PREFS, 0);
Editor editor = examplePrefs.edit();
editor.putString("usermessage", message);
editor.commit();
Intent i = new Intent(getApplicationContext(),
Wizard2Activity.class);
startActivity(i);
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is
present.
getMenuInflater().inflate(R.menu.wizard1, 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);
}
}
And Wizard 2 Activity:
package com.CENSORED.CENSORED;
import android.app.Activity;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.TextView;
public class Wizard2Activity extends Activity {
public static final String PREFS ="examplePrefs";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.wizard2);
TextView tv = (TextView)findViewById(R.id.textView1);
SharedPreferences example = getSharedPreferences(PREFS, 0);
String userString = example.getString("userMessage", "nothing");
tv.setText(userString);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is
present.
getMenuInflater().inflate(R.menu.wizard2, 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);
}
}
Thank you for your help! :)
You should change
String userString = example.getString("userMessage", "nothing");
to
String userString = example.getString("usermessage", "nothing");
key is usermessage. It's just typo.
Because the method
editor.putString("usermessage", message);
and
example.getString("userMessage", "nothing");
have different key.
i am having this error in this code
java.lang.runtimeexception unable to start activity componentinfo
package estimatewall.example.com.estimatewall;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends ActionBarActivity {
EditText inputTxt;
EditText inputTxt1;
TextView setText;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
inputTxt = (EditText) findViewById(R.id.editText);
// Store EditText in Variable
int val = Integer.parseInt(inputTxt.getText().toString());
inputTxt1 = (EditText) findViewById(R.id.editText2);
// Store EditText in Variable
int val1 = Integer.parseInt(inputTxt1.getText().toString());
float block1,block2;
final float sum;
block1=(val*12)/7;
block2=(val1*12)/10;
sum=block1*block2;
Button button = (Button) findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
// Perform action on click
try {
TextView textView = (TextView) findViewById(R.id.textView3);
textView.setText("" + sum);
}catch (Exception e)
{
e.printStackTrace();
}
}
});
}
#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);
}
}
Probably getting NumberFormatException because here:
int val = Integer.parseInt(inputTxt.getText().toString());
trying to convert null to int.
Use inputTxt.getText() inside onClick method of Button on click listener to get values input by user in Edittext or set some default values in xml for both EditText's as android:text="0"
Hey I was getting back into android programming, and was doing the developer.google.com tutorial and I dont know what is wrong here...
In the "public void sendMessage(View view) {" line, i get the error ';' expected.
Thanks in advance for your help.
package com.apps.graham.myfirstapp;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.content.Intent;
import android.view.View;
import android.widget.EditText;
public class MyActivity extends ActionBarActivity {
public final static String EXTRA_MESSAGE = "com.apps.graham.myfirstapp.MESSAGE";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my);
}
#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_my, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
//Called when the user clicks the send button next to the text field.
if (id == R.id.action_settings) return true;
{
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);
}
return super.onOptionsItemSelected(item);
}
}
}
Tricks:
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
//Called when the user clicks the send button next to the text field.
if (id == R.id.action_settings) {
//sendMessage(your-view); here, if you want to do that.
return true;
}
return super.onOptionsItemSelected(item);
}
And your new method can't be defined inside another method:
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);
}