Develop Reference

Notetoself Icon Add donn't appear

I'm new to Android Programming. I'm following the guide on Android Developers to get started with Android. When trying to run simple Note on the Emulator,the emulator Shows me an Errors... according the book musst appear a Icon and add a note ,,note that if you add a second note ,it will overwrite the first because i only have one Note object the Problem is that Icon Add donn't appear
dialog_new_note
<RelativeLayout
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/editTitle"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="35dp"
android:hint="#string/title_hint" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/editDescription"
android:layout_below="#+id/editTitle"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="35dp"
android:hint="#string/description_hint"
android:inputType="textMultiLine" />
<CheckBox
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/idea_checkbox"
android:id="#+id/checkBoxIdea"
android:layout_below="#+id/editDescription"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="35dp"
android:checked="false" />
<CheckBox
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/todo_checkbox"
android:id="#+id/checkBoxTodo"
android:layout_below="#+id/checkBoxIdea"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="35dp"
android:checked="false" />
<CheckBox
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/important_checkbox"
android:id="#+id/checkBoxImportant"
android:layout_below="#+id/checkBoxTodo"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="35dp"
android:checked="false" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/cancel_button"
android:id="#+id/btnCancel"
android:layout_marginTop="50dp"
android:layout_below="#+id/checkBoxImportant"
android:layout_toRightOf="#+id/editTitle"
android:layout_toEndOf="#+id/editTitle" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/ok_button"
android:id="#+id/btnOK"
android:layout_alignTop="#+id/btnCancel"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:layout_marginRight="53dp"
android:layout_marginEnd="53dp" />
</RelativeLayout>
Dialog_show_note
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/imageViewTodo"
android:layout_alignParentTop="true"
android:layout_toRightOf="#+id/imageViewImportant"
android:layout_toEndOf="#+id/imageViewImportant"
android:src="#drawable/ic_check_box_black_24dp" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/imageViewIdea"
android:layout_alignParentTop="true"
android:layout_toRightOf="#+id/imageViewTodo"
android:layout_toEndOf="#+id/imageViewTodo"
android:src="#drawable/ic_wb_incandescent_black_24dp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Large Text"
android:id="#+id/txtTitle"
android:layout_below="#+id/imageViewIdea"
android:layout_centerHorizontal="true"
android:layout_marginTop="27dp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="New Text"
android:id="#+id/txtDescription"
android:layout_marginTop="34dp"
android:layout_below="#+id/txtTitle"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="OK"
android:id="#+id/btnOK"
android:layout_marginBottom="101dp"
android:layout_alignParentBottom="true"
android:layout_alignLeft="#+id/txtTitle"
android:layout_alignStart="#+id/txtTitle" />
</RelativeLayout>
**menu_main.xml**
Content_main.xml
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Show Note"
android:id="#+id/button"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true" />
</RelativeLayout>
string_xml
Note To Self
Settings
<string name="action_add">add</string>
<string name="title_hint">Title</string>
<string name="description_hint">Description</string>
<string name="idea_checkbox">Idea</string>
<string name="important_checkbox">Important</string>
<string name="todo_checkbox">To do</string>
<string name="cancel_button">Cancel</string>
<string name="ok_button">OK</string>
<string name="sound_checkbox">On or Of</string>
<string name="settings_title">Settings</string>
<string name="sound_title">Sound</string>
<string name="amims_title">Animation Speed</string>
<string name="rb_fast">Fast</string>
<string name="rb_slow">Slow</string>
<string name="rb_none">None</string>
</resources>
**DialogNewNote**
>
public class DialogNewNote extends DialogFragment {
#Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
LayoutInflater inflater = getActivity().getLayoutInflater();
View dialogView = inflater.inflate(R.layout.dialog_new_note, null);
final EditText editTitle = (EditText) dialogView.findViewById(R.id.editTitle);
final EditText editDescription = (EditText) dialogView.findViewById(R.id.editDescription);
final CheckBox checkBoxIdea = (CheckBox) dialogView.findViewById(R.id.checkBoxIdea);
final CheckBox checkBoxTodo = (CheckBox) dialogView.findViewById(R.id.checkBoxTodo);
final CheckBox checkBoxImportant = (CheckBox) dialogView.findViewById(R.id.checkBoxImportant);
Button btnCancel = (Button) dialogView.findViewById(R.id.btnCancel);
Button btnOK = (Button) dialogView.findViewById(R.id.btnOK);
builder.setView(dialogView).setMessage("Add a new mNote");
btnCancel.setOnClickListener( new View.OnClickListener() {
#Override
public void onClick(View v) {
dismiss();
}
});
// Handle the OK button
btnOK.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// Create a new note
Note newNote = new Note();
// Set its variables to match the users entries on the form
newNote.setTitle(editTitle.getText().toString());
newNote.setDescription(editDescription.getText().toString());
newNote.setIdea(checkBoxIdea.isChecked());
newNote.setTodo(checkBoxTodo.isChecked());
newNote.setImportant(checkBoxImportant.isChecked());
// Get a reference to MainActivity
MainActivity callingActivity = (MainActivity) getActivity();
// Pass newNote back to MainActivity
callingActivity.createNewNote(newNote);
// Quit the dialog
dismiss();
}
});
return builder.create();
}
}
>
public class DialogShowNote extends DialogFragment {
private Note mNote;
public Dialog onCreateDialog(Bundle savedInstanceState) {
// Receive a note from the MainActivity
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
LayoutInflater inflater = getActivity().getLayoutInflater();
View dialogView = inflater.inflate(R.layout.dialog_show_note, null);
TextView txtTitle = (TextView) dialogView.findViewById(R.id.txtTitle);
TextView txtDescription = (TextView) dialogView.findViewByI (R.id.tx tDescription);
txtTitle.setText(mNote.getTitle());
txtDescription.setText(mNote.getDescription());
ImageView ivImportant = (ImageView) dialogView.findViewById(R.id.imageViewImportant);
ImageView ivTodo = (ImageView) dialogView.findViewById(R.id.imageViewTodo);
ImageView ivIdea = (ImageView) dialogView.findViewById(R.id.imageViewIdea);
if (!mNote.isImportant()) {
ivImportant.setVisibility(View.GONE);
}
if (!mNote.isTodo()) {
ivTodo.setVisibility(View.GONE);
}
if (!mNote.isIdea()) {
ivIdea.setVisibility(View.GONE);
}
Button btnOK = (Button) dialogView.findViewById(R.id.btnOK);
builder.setView(dialogView).setMessage("Your Note");
btnOK.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
dismiss();
}
});
return builder.create();
}
public void sendNoteSelected(Note noteSelected) {
mNote = noteSelected;
}
}
public class MainActivity extends AppCompatActivity {
// Temporary code
Note mTempNote = new Note();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Temporary code
Button button = (Button) findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// Create a new DialogShowNote called dialog
DialogShowNote dialog = new DialogShowNote();
// Send the note via the sendNoteSelected method
dialog.sendNoteSelected(mTempNote);
// Create the dialog
dialog.show(getFragmentManager(), "123");
}
});
}
public void createNewNote(Note n){
// Create a mNote
mTempNote = n;
}
#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;
}
if (id == R.id.action_add) {
DialogNewNote dialog = new DialogNewNote();
dialog.show(getFragmentManager(), "");
return true;
}
return super.onOptionsItemSelected(item);
}
}
5-16 15:32:20.654 2673-2673/com.example.melisa.notetoself W/System: ClassLoader referenced unknown path: /data/app/com.example.melisa.notetoself-2/lib/x86
05-16 15:32:20.934 2673-2673/com.example.melisa.notetoself W/art: Before Android 4.1, method android.graphics.PorterDuffColorFilter android.support.graphics.drawable.VectorDrawableCompat.updateTintFilter(android.graphics.PorterDuffColorFilter, android.content.res.ColorStateList, android.graphics.PorterDuff$Mode) would have incorrectly overridden the package-private method in android.graphics.drawable.Drawable
05-16 15:32:20.975 2673-2741/com.example.melisa.notetoself D/OpenGLRenderer: Use EGL_SWAP_BEHAVIOR_PRESERVED: true
05-16 15:32:21.042 2673-2741/com.example.melisa.notetoself I/OpenGLRenderer: Initialized EGL, version 1.4
05-16 15:32:23.438 2673-2741/com.example.melisa.notetoself E/Surface: getSlotFromBufferLocked: unknown buffer: 0xae3f2e30

Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference

All I want to do is start a new intent on click of a button. Here is my code(I have removed irrelevant parts):
activity_login.xml:
<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:gravity="center_horizontal"
tools:context="com.example.android.altro.LoginActivity">
<!-- Login progress -->
<ProgressBar
android:id="#+id/login_progress"
style="?android:attr/progressBarStyleLarge"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="8dp"
android:visibility="gone" />
<ScrollView
android:id="#+id/login_form"
android:layout_width="match_parent"
android:layout_height="match_parent">
<LinearLayout
android:id="#+id/email_login_form"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<android.support.design.widget.TextInputLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<AutoCompleteTextView
android:id="#+id/email"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="#string/prompt_email"
android:inputType="textEmailAddress"
android:maxLines="1"
android:textColor="#color/colorWhite"
android:singleLine="true" />
</android.support.design.widget.TextInputLayout>
<android.support.design.widget.TextInputLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<EditText
android:id="#+id/password"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="#string/prompt_password"
android:imeActionId="#+id/login"
android:imeActionLabel="#string/action_sign_in_short"
android:imeOptions="actionUnspecified"
android:inputType="textPassword"
android:maxLines="1"
android:singleLine="true" />
</android.support.design.widget.TextInputLayout>
<Button
android:id="#+id/email_sign_up_button"
style="?android:textAppearanceMedium"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#drawable/rounded_button"
android:onClick="registerNewUser"
android:text="#string/action_sign_up"
android:textAllCaps="false" />
</LinearLayout>
</ScrollView>
</LinearLayout>
On clicking #+id/email_sign_up_button registerNewUser is called. I have defined this fuction in LoginActivity.java:
public class LoginActivity extends AppCompatActivity implements LoaderCallbacks<Cursor> {
/**
* Id to identity READ_CONTACTS permission request.
*/
private static final int REQUEST_READ_CONTACTS = 0;
/**
* A dummy authentication store containing known user names and passwords.
* TODO: remove after connecting to a real authentication system.
*/
private static final String[] DUMMY_CREDENTIALS = new String[]{
"foo#example.com:hello", "bar#example.com:world"
};
/**
* Keep track of the login task to ensure we can cancel it if requested.
*/
private UserLoginTask mAuthTask = null;
// UI references.
private AutoCompleteTextView mEmailView;
private EditText mPasswordView;
private View mProgressView;
private View mLoginFormView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
// Set up the login form.
mEmailView = (AutoCompleteTextView) findViewById(R.id.email);
populateAutoComplete();
mPasswordView = (EditText) findViewById(R.id.password);
mPasswordView.setOnEditorActionListener(new TextView.OnEditorActionListener() {
#Override
public boolean onEditorAction(TextView textView, int id, KeyEvent keyEvent) {
if (id == R.id.login || id == EditorInfo.IME_NULL) {
attemptLogin();
return true;
}
return false;
}
});
Button mEmailSignInButton = (Button) findViewById(R.id.email_sign_in_button);
mEmailSignInButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View view) {
attemptLogin();
}
});
mLoginFormView = findViewById(R.id.login_form);
mProgressView = findViewById(R.id.login_progress);
/* Button mRegisterButton = (Button) findViewById(R.id.email_sign_up_button);
mRegisterButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(view.getContext(), RegisterActivity.class);
startActivity(intent);
}
});*/
}
public void registerNewUser(View view) {
Intent intent = new Intent(this, RegisterActivity.class);
startActivity(intent);
}
}
I also tried doing it by finding view and then creating an intent (the code is commented out in onCreate() method. That also gave me the same error:
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.android.altro/com.example.android.altro.RegisterActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference

You have only one Button with id email_sign_up_button
Please check your layout. Also try replacing
Button mEmailSignInButton = (Button) findViewById(R.id.email_sign_in_button);
With
Button mEmailSignInButton = (Button) findViewById(R.id.email_sign_up_button);

how to connect button with next screen on android studio

I am building this application on android studio and i am trying to link my button with next activity which is login screen. before i had it working with register screen but then i messed up with code now it just doesn't work when i run the application and click on register button my app crashes and shuts down and login button doesn't even do anything.
below is the code for main page activity and login page activity
first i will paste frontpage activity code where the button is, then its java class, then i will paste loginpage activity and then its java class.
can someone pls advice me how to call the login activity from the login button on the front page.
thank you so much in advance
frontpage activity
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".Login">
<LinearLayout
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:weightSum="1"
android:background="#drawable/bg3"
android:gravity="center|top">
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="Easy Booking"
android:id="#+id/textView"
android:textSize="33dp"
android:gravity="center"
android:textColor="#0c0c0c"
/>
<Button
android:layout_width="98dp"
android:layout_height="wrap_content"
android:layout_marginTop="50dp"
android:text="Login"
android:id="#+id/btLogin"
android:onClick="bLogin"
android:background="#null"
android:layout_gravity="center_horizontal" />
<Button
android:layout_width="108dp"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:text="Register"
android:id="#+id/btRegister"
android:onClick="bRegister"
android:background="#null"
android:layout_gravity="center_horizontal" />
</LinearLayout>
now its java class
public class Frontpage extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_frontpage);
//OnclickButtonListener();
}
public void bLogin(View view) {
}
public void onButtonClick(View v){
if (v.getId() == R.id.btRegister) {
Intent i = new Intent(new Intent(Frontpage.this, Register.class));
startActivity(i);
}
}
/**
public void OnclickButtonListener(){
button = (Button)findViewById(R.id.bRegister);
button.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent("/Users/umairfarooq/AndroidStudioProjects/Easybooking/app/src/main/res/layo ut/activity_register");
startActivity(intent);
}
}
);
} /**#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_activity_login, 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);
}
*/}
below is the login activity
xmlns:tools="http://schemas.android.com/tools"
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"
android:background="#635b5b"
android:orientation="vertical"
android:layout_width="match_parent">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Login Form"
android:textAppearance="?android:textAppearanceLarge"
android:textStyle="bold"
android:layout_gravity="center_horizontal"
android:layout_marginTop="10dp"
/>
<EditText
android:layout_width="250dp"
android:layout_height="wrap_content"
android:hint="Email"
android:id="#+id/etUsername"
android:layout_gravity="center_horizontal"
android:layout_marginTop="70dp"
/>
<EditText
android:layout_width="250dp"
android:layout_height="wrap_content"
android:hint="Password"
android:id="#+id/etPassword"
android:layout_gravity="center_horizontal"
android:layout_marginTop="20dp"
android:inputType="textPassword"
/>
<Button
android:layout_width="100dp"
android:layout_height="wrap_content"
android:text="Login"
android:layout_gravity="center_horizontal"
android:layout_marginTop="10dp"
android:onClick="userLogin"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Register Now"
android:layout_gravity="center_horizontal"
android:layout_marginTop="50dp"
android:onClick="userReg"
/>
</LinearLayout>
and now login java class
package com.example.umairfarooq.easybooking;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.View;
public class Login extends ActionBarActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
}
public void buttonOnClick (View v){
}
}

The problem is that your activities don't contain the methods that you've set for your buttons' android:onClick attribute.
For the layout that the Frontpage activity is using, you can either change btRegister button's android:onClick attribute to android:onClick="onButtonClick" or create a public void bRegister(View v){...} method in that activity.
For the Login activity, the layout has two buttons with their android:onClick attribute set to userReg and userLogin, you can either create those methods in the activity or change both of those attributes values to buttonOnClick.

when i run the application and click on register button my app crashes
and shuts down
It is because this button:
<Button
android:layout_width="108dp"
android:layout_height="wrap_content"
android:layout_marginTop="10dp"
android:text="Register"
android:id="#+id/btRegister"
android:onClick="bRegister"
android:background="#null"
android:layout_gravity="center_horizontal" />
in your frontpage activity needs a method with signature public void bRegister(View view) in your FrontPage.java class. As you do not have this method, it crashes.
login button doesn't even do anything
The reason is, this button
<Button
android:layout_width="98dp"
android:layout_height="wrap_content"
android:layout_marginTop="50dp"
android:text="Login"
android:id="#+id/btLogin"
android:onClick="bLogin"
android:background="#null"
android:layout_gravity="center_horizontal" />
in your frontpage activity needs a method called public void bLogin(View view) in your Frontpage.java class. Though the method is present, you do not have any code in it, hence it does not do anything.
You need to add proper code in bLogin method so that your login button starts functioning, and even before that add a bRegister method so that your register button starts working.
Hope this helps you.

Error inflating class Toolbar Android

i have some problem here when i want to use my own customize Toolbar instead the default system Toolbar, now i want to use that toolbar on my MainActivity.
i have make my own xml resource file for the toolbar, and i have included it on my MainActivity layout file, but when i run the app i got some error said
android.view.InflateException: Binary XML file line #2: Error inflating class android.support.v7.widget.toolbar
I don't know what happen, i have try to change the setting on my xml file but still the error appear.
Please master, help me.
Thanks Before.
NB. This my code for app_bar.xml (toolbar resource file)
<android.support.v7.widget.toolbar xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/primaryColor">
and this one for my MainActivity.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:background="#fafafa"
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=".MainActivity">
<include
android:id="#+id/app_bar"
layout="#layout/app_bar" />
<TextView
android:id="#+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:text="#string/Title"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="#f325272f"
android:textStyle="bold" />
<Button
android:id="#+id/btnNewTrans"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/textView"
android:layout_centerHorizontal="true"
android:layout_marginTop="73dp"
android:background="#drawable/custom_button"
android:text="#string/NewTransaction" />
<Button
android:id="#+id/btnViewCashflow"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBaseline="#+id/textView3"
android:layout_alignBottom="#+id/textView3"
android:layout_alignLeft="#+id/textView"
android:layout_alignStart="#+id/textView"
android:background="#drawable/custom_button"
android:text="#string/ViewCashflow" />
<Button
android:id="#+id/btnAddCateg"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="#+id/textView2"
android:layout_marginBottom="73dp"
android:layout_toLeftOf="#+id/btnRate"
android:layout_toStartOf="#+id/btnRate"
android:background="#drawable/custom_button"
android:text="#string/AddCategory" />
<Button
android:id="#+id/btnRate"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignBottom="#+id/btnAddCateg"
android:layout_alignLeft="#+id/spnCategSelect"
android:layout_alignStart="#+id/spnCategSelect"
android:text="#string/RateUs" />
<Button
android:id="#+id/btnSetting"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignTop="#+id/btnRate"
android:layout_toEndOf="#+id/btnRate"
android:layout_toRightOf="#+id/btnRate"
android:text="#string/Setting" />
<Button
android:id="#+id/btnAbout"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignTop="#+id/btnSetting"
android:layout_toEndOf="#+id/btnSetting"
android:layout_toRightOf="#+id/btnSetting"
android:text="#string/About" />
<TextView
android:id="#+id/textView2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:text="#string/Trademark"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="#f325272f"
android:textStyle="bold" />
<Spinner
android:id="#+id/spnCategSelect"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="#+id/btnAddCateg"
android:layout_alignEnd="#+id/textView"
android:layout_alignLeft="#+id/btnViewCashflow"
android:layout_alignRight="#+id/textView"
android:layout_alignStart="#+id/btnViewCashflow"
android:spinnerMode="dropdown" />
<TextView
android:id="#+id/textView3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/btnNewTrans"
android:layout_centerHorizontal="true"
android:layout_marginTop="38dp"
android:text="#string/SelectCategory"
android:textAppearance="?android:attr/textAppearanceSmall" />
and this one for my MainActivity.java
public class MainActivity extends AppCompatActivity implements OnItemSelectedListener {
private static Button BtnINewTrans;
private static Button BtnIViewCash;
private static Button BtnIAddCateg;
Spinner my_Spinner;
DatabaseHelper dbHelper = new DatabaseHelper(this);
public static String catSelected = null;
private Toolbar toolbar;
//ArrayAdapter<String> adapterCategory;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
toolbar=(Toolbar)findViewById(R.id.app_bar);
setSupportActionBar(toolbar);
my_Spinner = (Spinner)findViewById(R.id.spnCategSelect);
my_Spinner.setOnItemSelectedListener(this);
select_spinner_Category();
onButtonClickButtonListener();
}
/*ArrayList<String> my_array = new ArrayList<String>();
my_array = getTableValues();*/
/*ArrayAdapter my_Adapter = new ArrayAdapter(this, R.layout.spinner_row, my_array);
My_spinner.setAdapter(my_Adapter);*/
public void select_spinner_Category () {
my_Spinner = (Spinner)findViewById(R.id.spnCategSelect);
DatabaseHelper dbH = new DatabaseHelper(getApplicationContext());
List<String> listCategory = dbH.getAllCategory();
ArrayAdapter<String> adapterCategory = new ArrayAdapter<String>(this,
android.R.layout.simple_spinner_item, listCategory);
adapterCategory
.setDropDownViewResource(android.R.layout.simple_spinner_item);
my_Spinner.setAdapter(adapterCategory);
}
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position,
long id){
String label = parent.getItemAtPosition(position).toString();
Toast.makeText(parent.getContext(), "You selected "+label,
Toast.LENGTH_LONG).show();
catSelected = label;
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
}
public String getCatSelected(){
return catSelected;
}
/*ArrayList<String> arrayCategory;
arrayCategory = dbHelper.getAllCategory();
selectCategory = (Spinner) findViewById(R.id.spnCategSelect);
ArrayAdapter adapterCategory = new ArrayAdapter(this, android.R.layout.simple_spinner_item, arrayCategory);
// adapterCategory = new ArrayList<String>(this, android.R.layout.simple_spinner_item, R.id.spnCategSelect, AllCategoryList);
adapterCategory.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
selectCategory.setAdapter(adapterCategory);
selectCategory.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
Toast.makeText(getBaseContext(), parent.getItemAtPosition(position) + " selected", Toast.LENGTH_LONG).show();
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
}
});
}*/
#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;
}
public void onButtonClickButtonListener(){
BtnINewTrans = (Button)findViewById(R.id.btnNewTrans);
BtnINewTrans.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intentNewTrans = new Intent ("com.example.ever_ncn.cashflow.NewTransaction");
startActivity(intentNewTrans);
}
}
);
BtnIViewCash = (Button)findViewById(R.id.btnViewCashflow);
BtnIViewCash.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intentViewCash = new Intent ("com.example.ever_ncn.cashflow.ViewCashflow");
startActivity(intentViewCash);
}
}
);
BtnIAddCateg = (Button)findViewById(R.id.btnAddCateg);
BtnIAddCateg.setOnClickListener(
new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intentAddCateg = new Intent ("com.example.ever_ncn.cashflow.CategorySetting");
startActivity(intentAddCateg);
}
}
);
}
#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);
}
}

Classes are case sensitive: you have android.support.v7.widget.toolbar with a lowercase 't' when it should be android.support.v7.widget.Toolbar

Cannot change TextView between two activities?

I'm attempting to change a TextView between two activities. The problem is, when I change the text in the other activity from main activity, it works fine, the screen goes to the other activity and the text has been changed. However I have another button which takes me to the other activity from Main, but the newly updated text has disappeared when I press it. Any help?
MyActivity.java
public class MyActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my);
final EditText et = (EditText) findViewById(R.id.editText1);
Button b = (Button) findViewById(R.id.button1);
b.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(MyActivity.this, Second.class);
intent.putExtra("thetext", et.getText().toString());
startActivity(intent);
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.my, 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);
}
public void onClickGoToActivity(View view) {
setContentView(R.layout.second);
}
}
Second.java
public class Second extends Activity{
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.second);
TextView tv = (TextView) findViewById(R.id.textView1);
tv.setText(getIntent().getExtras().getString("thetext"));
}
}
activity_my.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=".MyActivity">
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/editText1"
android:layout_centerHorizontal="true"
android:hint="Change me"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/button1"
android:layout_centerHorizontal="true"
android:layout_marginTop="50dp"
android:text="Add text in other activity"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/go_to_activity_button"
android:text="Go to activity"
android:layout_centerHorizontal="true"
android:layout_marginTop="200dp"
android:onClick="onClickGoToActivity"/>
</RelativeLayout>
second.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/textView1"
android:textSize="30sp"/>
</LinearLayout>
AndroidManifest.xml
Second class activity:
I presume the problem lies here:
public void onClickGoToActivity(View view) {
setContentView(R.layout.second);
}
where the newly changed TextView is being reset back to the original layout (where the TextView is empty with no text). I'm not sure how to fix this as I'm new to Android.
Thank you.

changing content view of activity is a bad idea to start another activity. Simply you just do the same thing which is
public void onClickGoToActivity(View view) {
Intent intent = new Intent(MyActivity.this, Second.class);
intent.putExtra("thetext", et.getText().toString());
startActivity(intent);
}