Develop Reference

change the text in another activity

I have a button in Activity A, which changes the text in it when clicked. There is an Activity B in which I need the TextView to become visible and its text to be the same as the text in the button on the Activity A. Please help.
Activity A
package com.example.myapplication;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import androidx.annotation.Nullable;
public class SmActivity extends Activity {
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_sm);
Button btn_apple = (Button) findViewById(R.id.button_apple);
Button btn_cherry = (Button) findViewById(R.id.button_cherry);
Button btn_orange = (Button) findViewById(R.id.button_orange);
Button btn_waterLemon = (Button) findViewById(R.id.button_waterlemon);
View.OnClickListener appleListener = new View.OnClickListener() {
boolean action = false;
#Override
public void onClick(View v) {
if (!action) {
action = true;
btn_apple.setText("1");
}
else {
int i = Integer.parseInt(btn_apple.getText().toString());
btn_apple.setText(String.valueOf(i + 1));
i = i;
}
}
};
View.OnClickListener cherryListener = new View.OnClickListener() {
boolean action = false;
#Override
public void onClick(View v) {
if (!action) {
action = true;
btn_cherry.setText("1");
}
else {
int j = Integer.parseInt(btn_cherry.getText().toString());
btn_cherry.setText(String.valueOf(j + 1));
j = j;
}
}
};
View.OnClickListener orangeListener = new View.OnClickListener() {
boolean action = false;
#Override
public void onClick(View v) {
if (!action) {
action = true;
btn_orange.setText("1");
}
else {
int k = Integer.parseInt(btn_orange.getText().toString());
btn_orange.setText(String.valueOf(k + 1));
k = k;
}
}
};
View.OnClickListener waterListener = new View.OnClickListener() {
boolean action = false;
#Override
public void onClick(View v) {
if (!action) {
action = true;
btn_waterLemon.setText("1");
} else {
int q = Integer.parseInt(btn_waterLemon.getText().toString());
btn_waterLemon.setText(String.valueOf(q + 1));
q = q;
}
}
};
btn_apple.setOnClickListener(appleListener);
btn_cherry.setOnClickListener(cherryListener);
btn_orange.setOnClickListener(orangeListener);
btn_waterLemon.setOnClickListener(waterListener);
}
public void OnClickBsk(View view){
Intent intent = new Intent(SmActivity.this, BasketActivity.class);
startActivity(intent);
}
public void OnClickProfile(View view){
Intent intent = new Intent(SmActivity.this, ProfileActivity.class);
startActivity(intent);
}
}

Do this In Activity A when you click button to go to next Activity B
btn.setOnClickListener(v -> {
Intent i = new Intent(AActivity.this,BActivity.class);
// This below line sends Key- btnText and Value- Apple
i.putExtra("btnText","Apple");
startActivity(i);
});
In BActivity do this to button
// Here you receives data from activity a with the help of Key- btnText
btn.setText(getIntent().getStringExtra("btnText"));
This is a simple way to do this.

I Have Solved the answer for you,
Minor Explanations is in the comments in code.
Use this code as a concept and apply changes to yours based on your requirement.
XML of Activity A:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".ActivityA">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Text Before Button Click"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:id="#+id/text_to_change"
android:textSize="20sp"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#id/text_to_change"
android:id="#+id/change_text_btn"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:layout_margin="20dp"
android:text="Change Text and Start Activity B"
/>
</RelativeLayout>
Java of Activity A
package com.example.text_to_speech;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import org.w3c.dom.Text;
public class ActivityA extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_activity);
TextView textView;
Button button;
textView=findViewById(R.id.text_to_change);
button=findViewById(R.id.change_text_btn);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String newtext="New Text From Activity A";
textView.setText(newtext);
Intent intent=new Intent(ActivityA.this,ActivityB.class);
intent.putExtra("Change", newtext);//this string will be
//accessed by activityB
startActivity(intent);
}
});
}
}
XML of Activity B:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".ActivityB">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Waiting for New Text"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:id="#+id/new_textview"
android:textSize="20sp"
android:visibility="gone"
/>
</RelativeLayout>
Java of Activity B:
package com.example.text_to_speech;
import androidx.appcompat.app.AppCompatActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;
import android.widget.Toast;
public class ActivityB extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_b);
TextView textView;
textView=findViewById(R.id.new_textview);
// Below if block is looking for an intent, if it gets it and
// there is content in the extras with key "Change",
// it will make the textview in xml visible and update its string
// based on value set by Activity A
if(savedInstanceState == null) {
Bundle extras = getIntent().getExtras();
if (extras == null) {
Toast.makeText(ActivityB.this, "Can't Get the Intent", Toast.LENGTH_LONG).show();
} else {
String get_String = extras.getString("Change");
textView.setVisibility(View.VISIBLE);// be default i have set the visibility to gone in xml
//here it will get visible and then filled with the string sent by the intent in activity A
textView.setText(get_String);
}
}
}
}

Multiple Intents on Change of BG Color from one activity to the other # Android

My initial plan was to have a UI preference so the user can pick a bg color from the main activity whenever he/she wants - I got that to work BUT it isn't showing up the right color it's specified to. i.e. When Red button is pressed in Main Activity, it shows up Blue in the next activity instead.
Here is a snippet of the code with only two buttons using multiple intents for demo purposes...
My Main layout:
<Button
android:id="#+id/buttonRed"
android:onClick="passBG"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="RED"
android:layout_marginLeft="18dp"
android:layout_marginStart="18dp"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<Button
android:id="#+id/buttonBlue"
android:onClick="passBG"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="BLUE"
android:layout_alignParentBottom="true"
android:layout_alignLeft="#+id/button"
android:layout_alignStart="#+id/button" />
Main Activity is working:
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.content.Intent;
import android.view.View;
public class MainActivity extends AppCompatActivity {
View view;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
view=this.getWindow().getDecorView();
view.setBackgroundResource(R.color.gray);
public void passBG(View v) {
Intent intent = new Intent(this, AudioActivity.class);
intent.putExtra("Red", R.color.red);
intent.putExtra("Blue", R.color.blue);
startActivity(intent);
}
}
But something's not right with the second Activity:
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.RelativeLayout;
public class AudioActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_audio);
int redBG = getIntent().getIntExtra("Red", -1);
int blueBG = getIntent().getIntExtra("Blue", -1);
RelativeLayout rootView = (RelativeLayout) findViewById(R.id.activity_audio);
rootView.setBackgroundResource(redBG);
rootView.setBackgroundResource(blueBG);
}
}
I figured out that whichever color in "..."BG is implemented first in
rootView.setBackgroundResource("..."BG)
will determine the one that will only pop out. It's something to do with the sequence I figured - AT FIRST ATTEMPT, I tried using the intents on separate methods i.e.
public void goRED(View v)
{
view.setBackgroundResource(R.color.red);
Intent intent = new Intent(this, AudioActivity.class);
intent.putExtra("Red", R.color.red);
startActivity(intent);
}
public void goBLUE(View v)
{
view.setBackgroundResource(R.color.blue);
Intent intent = new Intent(this, AudioActivity.class);
intent.putExtra("Blue", R.color.blue);
startActivity(intent);
}
BUT THAT WILL ONLY END UP IN ERROR so I called the buttons on the same method to prevent that problem. So now I'm stuck with a new problem - how do I correctly implement multiple intents to show up the right color BG on the next activity? should I use some if-else statement into it? Any help would be appreciated. Thanks!

Well try this:
Main Activity is working:
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.content.Intent;
import android.view.View;
public class MainActivity extends AppCompatActivity {
View view;
private Button redBtn;
private Button blueBtn;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
view=this.getWindow().getDecorView();
view.setBackgroundResource(R.color.gray); //This can be achieved by using the `android:background` attribute to your main element on your activity layout
redBtn = (Button) findViewById(R.id.buttonRed); //also, attributes ids on xml layouts shouldnt use uppercase letters, separete words using '_'
blueBtn = (Button) findViewById(R.id.buttonBlue);
redBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
onButtonClick(R.color.red);
}
});
blueBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
onButtonClick(R.color.blue);
}
});
}
private void onButtonClick(int color){
Intent intent = new Intent(this, AudioActivity.class);
intent.putIntExtra("background",color);
startActivity(intent);
}
}
then, on your second activity:
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.RelativeLayout;
public class AudioActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_audio);
int color = getIntent().getIntExtra("background", -1);
if(color != -1){
RelativeLayout rootView = (RelativeLayout) findViewById(R.id.activity_audio);
rootView.setBackgroundResource(color);
}
}
}

android onClick Does not work

The code worked fine in other layout, but in others not..
layout XML:
<Button
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="register"
android:id="#+id/welcome_register"
android:background="#android:color/holo_green_dark"
android:textColor="#ffffff"
android:textSize="25sp"
android:onClick="register_Click" />
Activity:
package il.co.smartchip.hobby;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
public class LoginActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
getSupportActionBar().hide();
}
public void start_login(View view) {
//TODO log in
}
public void register_Click(View view) {
Intent intent = new Intent(this, RegisterActivity.class);
startActivity(intent);
}
I tried several things without success. Do you have any idea why it does not work?

In your case you need Intent i = new Intent(LoginActivity.this, RegisterActivity.class);.
LoginActivity.this points to the instance of the Activity you are currently in and you using it when you work with dynamic inner class like in your case.
this is for your current Object.
Im not so good teacher, hope you understand it.

Delete onclick on xml
<Button
android:layout_width="match_parent"
android:layout_height="match_parent"
android:text="register"
android:id="#+id/welcome_register"
android:background="#android:color/holo_green_dark"
android:textColor="#ffffff"
android:textSize="25sp"
/>
Init your button like that
package il.co.smartchip.hobby;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
public class LoginActivity extends AppCompatActivity {
private Button myButton;
private Activity thisActivity=this;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
getSupportActionBar().hide();
myButton=(Button)findViewById(R.id.welcome_register);
myButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(thisActivity, RegisterActivity.class);
startActivity(intent);
}
});
}}

Button not working in android app?

I'm building an app which has 3 functions a converter, a calculator and a notes section. When I click on the converter button on the home page it brings me to the converter activity / page. But when I click on the calculator button on the home page it won't open. Here is the code below. Any reason as to why? Thanks in advance.
MainActivity
package com.qub.buildersbuddy;
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.Button;
import android.widget.Toast;
public class MainActivity extends Activity {
Button buttonConverter;
Button buttonCalculator;
Button buttonNotePad;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button ConvertBtn = (Button) findViewById(R.id.butonConverter);
ConvertBtn.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this,CentInch.class);
startActivity(intent);
}
});
}
public void setupConverterButton(){
buttonConverter = (Button) findViewById(R.id.butonConverter);
// Button messageButton = (Button) findViewById(R.id.butonConverter);
}
public void CentToInch(){
buttonConverter.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
//opening the
try{
Class centClass = Class
.forName("com.qub.buildersbuddy.CentInch");
Intent myintent = new Intent(MainActivity.this,centClass);
startActivity(myintent);
}catch (ClassNotFoundException e){
e.printStackTrace();
}
}
});
}
protected void onCreate1(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button CalcBtn = (Button) findViewById(R.id.buttonCalc);
CalcBtn.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this,Calculator.class);
startActivity(intent);
}
});
}
public void setupCalculatorButton(){
buttonCalculator = (Button) findViewById(R.id.buttonCalc);
// Button messageButton = (Button) findViewById(R.id.butonConverter);
}
public void Calculator(){
buttonCalculator.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
//opening the
try{
Class calcClass = Class
.forName("com.qub.buildersbuddy.Calculator");
Intent myintent = new Intent(MainActivity.this,calcClass);
startActivity(myintent);
}catch (ClassNotFoundException e){
e.printStackTrace();
}
}
});
}
}
activity_main:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context=".CentInch" >
<Button
android:id="#+id/butonConverter"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="62dp"
android:text="Converter" />
<Button
android:id="#+id/buttonCalc"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/butonConverter"
android:layout_centerHorizontal="true"
android:layout_marginTop="28dp"
android:text="Calculator" />
<Button
android:id="#+id/buttonNotes"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/buttonCalc"
android:layout_centerHorizontal="true"
android:layout_marginTop="31dp"
android:text="Notes" />
</RelativeLayout>

Is this the exact code you're using? Your #onCreate1 method will never get called. #onCreate gets called because it overrides a method from the class you extended (Activity), and something in Activity calls the method when the activity first starts. Move your calculator button logic into the first #onCreate method.

layout elements not showing up

I have two activities and the first is generating properly however the second is not. only the first element in the xml file will show up. here is my xml file:
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/alternateActivity"
android:shadowColor="#color/shadowColor"></TextView>
<Button
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="#+id/oldActivityButton"
android:text="#string/oldActivityButton"></Button>
<Button
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="#+id/changeText"
android:text="#string/changeTextButton"></Button>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/originalText"
android:id="#+id/textToChange"></TextView>
</LinearLayout>
and here is my activity that corresponds:
package fsg.dev.activitytest;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;
public class newActivity extends Activity {
private Button oldActivityButton;
private Button changeText;
private TextView textToChange;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.alternate);
oldActivityButton = (Button) findViewById(R.id.oldActivityButton);
changeText = (Button) findViewById(R.id.changeText);
textToChange = (TextView) findViewById(R.id.textToChange);
oldActivityButton.setOnClickListener(new OnClickListener(){
public void onClick(View view){
changeActivity();
}
});
changeText.setOnClickListener(new OnClickListener(){
public void onClick(View view){
changeText();
}
});
}
private void changeActivity(){
Intent i = new Intent(this, activityTest.class);
startActivity(i);
}
private void changeText(){
if(textToChange.equals(R.string.originalText)){
textToChange.setText(R.string.newText);
} else {
textToChange.setText(R.string.originalText);
}
}
}
has anyone else seen this problem? or know of a way to fix it?

Try to add android:orientation="vertical" to your LinearLayout

replace
Intent i = new Intent(this, activityTest.class);
by
Intent i = new Intent().setClass(this, activityTest.class);