Rectangle Area Calculation

Rectangle Area Calculation - java

I am trying to calculate the rectangle area in my application. I have created a simple layout but for some reason, data is not parsed into the application. I tried to print it in the console but nothing is shown.
This is my Main Class:
package com.example.week3labcode;
import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
Button calcButton;
EditText number1, number2, resultFinal;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
calcButton = (Button)findViewById(R.id.button1);
number1 = (EditText) findViewById(R.id.edtext1);
number2 = (EditText) findViewById(R.id.edtext2);
resultFinal = (EditText) findViewById(R.id.edtext3);
}
#Override
public void onClick(View v){
if(v == calcButton){
number1 = (EditText) findViewById(R.id.edtext1);
number2 = (EditText) findViewById(R.id.edtext2);
double num1 = Double.parseDouble(number1.getText().toString());
double num2 = Double.parseDouble(number2.getText().toString());
calcRectangle(num1, num2);
}
}
public void calcRectangle(double x, double y){
double result = x * y;
System.out.println(result);
resultFinal = (EditText) findViewById(R.id.edtext3);
resultFinal.setText(Double.toString(result));
System.out.println('H' + result);
}
}
And the following code in my XML file that provides layout for the application:
<?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=".MainActivity">
<TextView
android:id="#+id/label1"
android:layout_centerHorizontal="true"
android:layout_marginVertical="20px"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Rectangle Area Calculation" />
<TextView
android:id="#+id/label2"
android:layout_below="#+id/label1"
android:layout_centerHorizontal="true"
android:layout_marginVertical="10px"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Enter Length" />
<EditText
android:id="#+id/edtext1"
android:layout_toRightOf="#+id/label2"
android:layout_centerHorizontal="true"
android:layout_alignBaseline="#+id/label2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="" />
<TextView
android:id="#+id/label3"
android:layout_below="#+id/label2"
android:layout_centerHorizontal="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Enter breadth" />
<EditText
android:id="#+id/edtext2"
android:layout_toRightOf="#+id/label3"
android:layout_alignBaseline="#+id/label3"
android:layout_centerHorizontal="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="" />
<Button
android:id="#+id/button1"
android:layout_below="#+id/label3"
android:layout_centerHorizontal="true"
android:layout_marginTop="50px"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Calculate" />
<TextView
android:id="#+id/label4"
android:layout_below="#+id/button1"
android:layout_centerHorizontal="true"
android:layout_marginVertical="20px"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Area in cm2" />
<EditText
android:id="#+id/edtext3"
android:layout_toRightOf="#+id/label4"
android:layout_centerHorizontal="true"
android:layout_alignBaseline="#+id/label4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="" />
<Button
android:id="#+id/button2"
android:layout_below="#+id/label4"
android:layout_centerHorizontal="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Clear Entries" />
</RelativeLayout>

You have not set OnClickListener to your Button so calcRectangle() method is never called.
calcButton = (Button)findViewById(R.id.button1);
calcButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View view) {
number1 = (EditText) findViewById(R.id.edtext1);
number2 = (EditText) findViewById(R.id.edtext2);
double num1 = Double.parseDouble(number1.getText().toString());
double num2 = Double.parseDouble(number2.getText().toString());
calcRectangle(num1, num2);
}
});
OR
calcButton.setOnClickListener(this);

Related

Trying to receive input and display if it's correct or incorrect using ANDROID STUDIO

**activity_main xml**
<?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:id="#+id/activity_main"
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="com.example.hynes.equations.MainActivity">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Please select what type of equation to solve"
android:id="#+id/textView2" />
<Button
android:text="Check"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignRight="#+id/textView3"
android:layout_alignEnd="#+id/textView3"
android:layout_marginRight="230dp"
android:layout_marginEnd="230dp"
android:id="#+id/button2" />
<TextView
android:layout_centerVertical="true"
android:id="#+id/textView5"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_height="50dp"
android:layout_width="250dp"
android:layout_alignRight="#+id/textView2"
android:layout_alignEnd="#+id/textView2" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="number"
android:ems="10"
android:layout_above="#+id/button2"
android:layout_alignRight="#+id/textView5"
android:layout_alignEnd="#+id/textView5"
android:layout_marginRight="170dp"
android:layout_marginEnd="170dp"
android:layout_marginBottom="36dp"
android:id="#+id/editText2" />
<RadioGroup android:id="#+id/radio_group"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true">
<RadioButton
android:text="Addition"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/textView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="26dp"
android:id="#+id/addition"
android:onClick="onRadioButtonClicked"/>
<RadioButton
android:text="Subtraction"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/radioButton"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="14dp"
android:id="#+id/subtraction"
android:onClick="onRadioButtonClicked"/>
<RadioButton
android:text="Division"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/radioButton2"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="16dp"
android:id="#+id/division"
android:onClick="onRadioButtonClicked"/>
<RadioButton
android:text="Multiplication"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/radioButton3"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="20dp"
android:id="#+id/multiplication"
android:onClick="onRadioButtonClicked"/>
</RadioGroup>
`
MAIN ACTIVITY
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.EditText;
import android.widget.RadioButton;`
import android.widget.RadioGroup;
import android.widget.TextView;
import java.util.Random;
public class MainActivity extends AppCompatActivity {
private int x;
private int y;
public int a;
public int b;
Random random = new Random();
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void onRadioButtonClicked(View view){
TextView display = (TextView) findViewById(R.id.textView5);
RadioGroup radioGroup = (RadioGroup) findViewById(R.id.radio_group);
int btnID = radioGroup.getCheckedRadioButtonId();
switch(btnID){
case R.id.addition:
x = random.nextInt(100);
y = random.nextInt(100);
display.setText(x + "+" + y + "=");
break;
case R.id.subtraction:
x = random.nextInt(100);
y = random.nextInt(100);
display.setText(x + "-" + y + "=");
break;
case R.id.division:
y = random.nextInt(5);
x = y*2;
display.setText(x + "/" + y + "=");
break;
case R.id.multiplication:
x = random.nextInt(10);
y = random.nextInt(10);
display.setText(x + "*" + y + "=");
break;
}
public void onClickCheck(View view){
TextView result = (TextView) findViewById(R.id.textView5);
EditText ans = (EditText) findViewById(R.id.editText2);
RadioGroup radioGroup = (RadioGroup) findViewById(R.id.radio_group);
int btnID = radioGroup.getCheckedRadioButtonId();
if(boolean(RadioButton) findViewById(R.id.addition)) ){
int key = x+y;
int try = 0;
while(!ans.equals(key)){
try = try + 1;
if(try ==0){
result.setText("Incorrect, try again!");
try++
}else if (try>2){
result.setText("Incorrect, the answer is : " + key);
}
if(ans.equals(key)){
result.setText("You are correct !");
}
}
}
}
}
}
}
This is a android studio app that's suppose to randomly generate a math equation upon creation which I've done. There's addition, subtraction, division, and multiplication. My random equation generator works perfectly. But I'm stuck at my onClickCheck method which i want to get the user's answer/input and check to see if it's correct or incorrect and display a message accordingly. My onClick method is wrong but it's a start. I don't know what methods i need to get my code to accept inputs properly. Any help would be appreciated.

It looks like you aren't assigning an OnClickListener to the button.
You need to put:(in onCreate)
Button button = (Button)findViewById(R.id.button2);
button.setOnClickListener(onClickCheck);
or
Button button = (Button)findViewById(R.id.button2);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
onClickCheck(view);
}
});
Same for the radio button.

Android studio, android scrolling down and up enable

I want to add something like scrolling from top to bottom and vice versa but i don't know how to add this function, i was trying with ScrollView but that gave nothing.
MainActivity.java :
package com.example.marek.przelicznikpaliw;
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.EditText;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends ActionBarActivity {
private EditText a1;
private EditText b1;
private EditText c1;
private EditText d1;
private TextView tv;
private TextView tv2;
private TextView tv3;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//pola
a1 = (EditText) findViewById(R.id.cel);
b1 = (EditText) findViewById(R.id.pali);
c1 = (EditText) findViewById(R.id.litr);
d1 = (EditText) findViewById(R.id.koszt);
// wynik
tv = (TextView) findViewById(R.id.wynikKoszt);
tv2 = (TextView) findViewById(R.id.wynikKilometry);
tv3 = (TextView) findViewById(R.id.wynikKosztx2);
findViewById(R.id.button).setOnClickListener(onClickListener);
findViewById(R.id.button2).setOnClickListener(onClickListener);
}
private View.OnClickListener onClickListener = new View.OnClickListener() {
#Override
public void onClick(View view) {
float a = 0;
float b = 0;
float c = 0;
float d = 0;
float wynik = 0;
float wynik2 = 0;
float wynik3 = 0;
try {
a = Float.parseFloat(a1.getText().toString());
b = Float.parseFloat(b1.getText().toString());
c = Float.parseFloat(c1.getText().toString());
d = Float.parseFloat(d1.getText().toString());
} catch (Exception e) {
e.printStackTrace();
}
if (view.getId() == R.id.button) {
wynik = ((b / 100) * a) * c;
tv.setText(String.valueOf(wynik));
wynik2 = (((b / 100) * a) * c)*2;
tv3.setText(String.valueOf(wynik2));
} else if (view.getId() == R.id.button2) {
wynik3 = d / ((b * c) / 100);
tv2.setText(String.valueOf(wynik3));
}
}
};
}
activity_main.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: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:orientation="vertical"
android:onClick="onButtonClick"
android:weightSum="1">
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/cel"
android:hint="Ilosc km do celu to:"
android:layout_centerHorizontal="true"
android:numeric="integer|decimal" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/pali"
android:hint="Ile litrow pali na 100km"
android:layout_centerHorizontal="true"
android:layout_below="#+id/cel"
android:numeric="integer|decimal" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/litr"
android:hint="Cena za litr"
android:layout_below="#+id/pali"
android:layout_centerHorizontal="true"
android:numeric="integer|decimal" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/button"
android:layout_below="#+id/litr"
android:layout_centerHorizontal="true"
android:hint="Licz zlotowki"
android:text="Licz koszty"
android:clickable="true" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/koszt"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true"
android:hint="Za ile zl zostalo zatankowane gaz/paliwo?"
android:numeric="integer|decimal" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Licz kilometry"
android:id="#+id/button2"
android:layout_below="#+id/koszt"
android:layout_centerHorizontal="true"
android:clickable="true" />
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Dojedziesz w wybrany cel za(zł):"
android:id="#+id/textView" />
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="#string/emptystring"
android:id="#+id/wynikKoszt"
android:textIsSelectable="false" />
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Oraz spowrotem za(zł):"
android:id="#+id/textView2" />
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/emptystring"
android:id="#+id/wynikKosztx2"
android:layout_weight="0.06" />
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Za tę kwotę przejedziesz(km):"
android:id="#+id/textView3" />
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="#string/emptystring"
android:id="#+id/wynikKilometry" />

(Android)Trying to understand why my method will not compute/display the correct value in the textview

My method that is called (calculate BMI) inside of my activity is supposed to compute and display BMI (based on the formula inside the code), and display its value inside of a textview. The application runs correctly, however the value displayed is always zero. I am struggling to figure out if the problem lies in my formula (unlikely) or if the way that I am passing the value is incorrect. Any help would be appreciated. Code below
.Java file
import android.content.Intent;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.EditText;
import android.widget.TextView;
import android.view.View;
import android.widget.Toast;
public class Health extends ActionBarActivity {
EditText bloodPressure;
EditText cholesterol;
int weight;
int height;
EditText heightString;
EditText age;
TextView bmiText;
EditText weightString;
MyDBHandler dbHandler;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_health);
weightString = (EditText) findViewById(R.id.weightTextBox);
heightString =(EditText) findViewById(R.id.heightTextBox);
bmiText = (TextView) findViewById(R.id.bmiTextView);
bloodPressure = (EditText) findViewById(R.id.bloodPressureTextBox);
cholesterol = (EditText) findViewById(R.id.cholesterolTextBox);
age = (EditText) findViewById(R.id.ageTextBox);
dbHandler = new MyDBHandler(this, null, null, 1);
}
public void calculateBMI(View view)
{
weight = Integer.parseInt(weightString.getText().toString());
height = Integer.parseInt(heightString.getText().toString());
int BMI = 703 * (weight/(height*height));
bmiText.setText("Your calculated BMI is: " + Integer.toString(BMI));
Toast.makeText(Health.this, " Info Saved ", Toast.LENGTH_SHORT).show();
HealthInfo healthInfo = new HealthInfo(bloodPressure.getText().toString(),cholesterol.getText().toString(),heightString.getText().toString(),weightString.getText().toString(),age.getText().toString());
dbHandler.addHealth(healthInfo);
}
public void calorieClick(View view){
Intent i = new Intent(this, CalorieTracker.class);
startActivity(i);
}
public void openTips(View view){
Intent i = new Intent(this, HealthTipsActivity.class);
startActivity(i);
}
public void openPlans(View view){
Intent i = new Intent(this, DietPlansActivity.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.menu_health, 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);
}
}
.XML file
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin"
tools:context="seniorproject.broncos.broncowellnessapp.Health"
android:background="#006699">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="#string/blood_pressure_text"
android:id="#+id/bloodPressureTextView"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="#string/cholesterol_text"
android:id="#+id/cholesterolTextView"
android:layout_below="#+id/bloodPressureTextView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="35dp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="#string/weight_text"
android:id="#+id/weightTextView"
android:layout_below="#+id/cholesterolTextView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="35dp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="#string/height_text"
android:id="#+id/heightTextView"
android:layout_below="#+id/weightTextView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="35dp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="#string/age_text"
android:id="#+id/ageTextView"
android:layout_below="#+id/heightTextView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="35dp" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="text"
android:ems="10"
android:width="150dp"
android:id="#+id/bloodPressureTextBox"
android:layout_below="#+id/bloodPressureTextView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="number"
android:ems="10"
android:width="150dp"
android:id="#+id/cholesterolTextBox"
android:layout_below="#+id/cholesterolTextView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="number"
android:ems="10"
android:width="150dp"
android:id="#+id/weightTextBox"
android:layout_below="#+id/weightTextView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="number"
android:ems="10"
android:width="150dp"
android:id="#+id/heightTextBox"
android:layout_below="#+id/heightTextView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="number"
android:ems="10"
android:width="150dp"
android:id="#+id/ageTextBox"
android:layout_below="#+id/ageTextView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/diet_plans_button_text"
android:onClick="openPlans"
android:id="#+id/dietPlansButton"
android:layout_below="#+id/ageTextBox"
android:layout_marginTop="40dp"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true" />
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/calorie_tracker_button"
android:id="#+id/calorieAccessButton"
android:layout_below="#+id/dietPlansButton"
android:onClick ="calorieClick"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true" />
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="#string/tips_button_text"
android:id="#+id/tipsButton"
android:onClick="openTips"
android:layout_below="#+id/calorieAccessButton"
android:layout_alignRight="#+id/calorieAccessButton"
android:layout_alignEnd="#+id/calorieAccessButton" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/BMI_button_text"
android:id="#+id/bmiButton"
android:onClick="calculateBMI"
android:layout_alignBottom="#+id/cholesterolTextBox"
android:layout_alignRight="#+id/dietPlansButton"
android:layout_alignEnd="#+id/dietPlansButton"
android:layout_marginRight="36dp"
android:layout_marginEnd="36dp"
android:background="#ff00b812" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceSmall"
android:text="Push Button to Compute BMI"
android:id="#+id/bmiTextView"
android:layout_alignBottom="#+id/weightTextBox"
android:layout_alignLeft="#+id/bmiButton"
android:layout_alignStart="#+id/bmiButton" />
</RelativeLayout>

Your weight and height variables are int. That is your problem. Change them to float or double
Currently, you are doing integer division which is causing the result to be truncated as follows: 1 / 2 gives 0

You are doing a division for integer which results mostly to zero.
That is why the result is always zero.
Change your weight and height variables to double like this
and just cast the result back to int.
double weight = 0.0;
double height = 0.0;
int BMI = (int)(703 * (weight/(height*height)));
bmiText.setText("Your calculated BMI is: " + Integer.toString(BMI));

Place this on the end of the onCreate() method:
findViewById(R.id.bmiButton).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
weight = Integer.parseInt(weightString.getText().toString());
height = Integer.parseInt(heightString.getText().toString());
int BMI = 703 * (weight/(height*height));
bmiText.setText("Your calculated BMI is: " + Integer.toString(BMI));
Toast.makeText(Health.this, " Info Saved ", Toast.LENGTH_SHORT).show();
HealthInfo healthInfo = new HealthInfo(bloodPressure.getText().toString(),cholesterol.getText().toString(),heightString.getText().toString(),weightString.getText().toString(),age.getText().toString());
dbHandler.addHealth(healthInfo);
}
});
Some android version does not support onClick attribute for Button tag in XAML.

Moving TextView Box made my android app crash

I have had this problem crop up a few times and I can't figure out why it should happen. What happened was after moving some stuff around my TextView box ended up on top of an EditText box, which is no good. So I went and moved the TextView box to the bottom of the screen. When I did that, the app would crash when I tried to access the piggybank. However, if I move the TextView box up to the top again, it works fine.. I really don't get it. Anyways, this is the error that I got
06-22 09:06:41.928: E/AndroidRuntime(10958): java.lang.RuntimeException: Unable to
start activity ComponentInfo{net.finalexam/net.finalexam.Piggy}:
java.lang.ClassCastException: android.widget.RadioButton
This is piggy xml file
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#drawable/piggy" >
<EditText
android:id="#+id/txtQuarters"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="27dp"
android:ems="10"
android:hint="Number of quarters"
android:inputType="number" >
<requestFocus />
</EditText>
<EditText
android:id="#+id/txtDimes"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/txtQuarters"
android:layout_centerHorizontal="true"
android:ems="10"
android:hint="Number of dimes"
android:inputType="number" />
<EditText
android:id="#+id/txtNickles"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/txtDimes"
android:layout_centerHorizontal="true"
android:ems="10"
android:hint="Number of nickles"
android:inputType="number" />
<EditText
android:id="#+id/txtPennies"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/txtNickles"
android:layout_centerHorizontal="true"
android:ems="10"
android:hint="Number of pennies"
android:inputType="number" />
<EditText
android:id="#+id/txtDollars"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/txtPennies"
android:layout_centerHorizontal="true"
android:ems="10"
android:hint="Number of Dollars"
android:inputType="number" />
<RadioGroup
android:id="#+id/radioGroup1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/txtDollars"
android:layout_centerHorizontal="true" >
<RadioButton
android:id="#+id/radAdd"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:checked="true"
android:text="Add" />
<RadioButton
android:id="#+id/radSubtract"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Subtract" />
</RadioGroup>
<Button
android:id="#+id/btnCalculate"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/radioGroup1"
android:layout_centerHorizontal="true"
android:text="Calculate" />
<TextView
android:id="#+id/txtResults"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/btnCalculate"
android:layout_centerHorizontal="true"
android:layout_marginTop="27dp"
android:textSize="40sp" android:textStyle="bold" android:textColor="#000000"/>
</RelativeLayout>
This is the Piggy Java file
package net.finalexam;
import java.text.DecimalFormat;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import android.widget.RadioButton;
import android.widget.TextView;
import android.widget.Toast;
public class Piggy extends Activity
{
double quartersValue = .25;
double dimesValue = .10;
double nicklesValue = .05;
double penniesValue = .01;
double dollarsValue = 1;
double quartersMoney;
double dollarsMoney;
double dimesMoney;
double nicklesMoney;
double penniesMoney;
double totalMoney;
double newTotalMoney;
double oldTotalMoney = 0;
int numberOfQuarters;
int numberOfDimes;
int numberOfNickles;
int numberOfPennies;
int numberOfDollars;
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.piggybank);
final EditText quarters = (EditText) findViewById(R.id.txtQuarters);
final EditText dimes = (EditText) findViewById(R.id.txtDimes);
final EditText nickles = (EditText) findViewById(R.id.txtNickles);
final EditText pennies = (EditText) findViewById(R.id.txtPennies);
final EditText dollars = (EditText) findViewById(R.id.txtDollars);
Button calculate = (Button) findViewById(R.id.btnCalculate);
final TextView results = ((TextView) findViewById(R.id.txtResults));
final RadioButton add = (RadioButton) findViewById(R.id.radAdd);
final RadioButton subtract = (RadioButton) findViewById(R.id.radSubtract);
calculate.setOnClickListener(new OnClickListener()
{
public void onClick(View v)
{
if (quarters.getText().toString().equals(""))
{
numberOfQuarters = 0;
}
else
{
numberOfQuarters = Integer.parseInt(quarters.getText().toString());
}
if (dimes.getText().toString().equals(""))
{
numberOfDimes = 0;
}
else
{
numberOfDimes = Integer.parseInt(dimes.getText().toString());
}
if (nickles.getText().toString().equals(""))
{
numberOfNickles = 0;
}
else
{
numberOfNickles = Integer.parseInt(nickles.getText().toString());
}
if (pennies.getText().toString().equals(""))
{
numberOfPennies = 0;
}
else
{
numberOfPennies = Integer.parseInt(pennies.getText().toString());
}
if (dollars.getText().toString().equals(""))
{
numberOfDollars = 0;
}
else
{
numberOfDollars = Integer.parseInt(dollars.getText().toString());
}
quartersMoney = numberOfQuarters * quartersValue;
dimesMoney = numberOfDimes * dimesValue;
nicklesMoney = numberOfNickles * nicklesValue;
penniesMoney = numberOfPennies * penniesValue;
dollarsMoney = numberOfDollars;
totalMoney = quartersMoney + dimesMoney + nicklesMoney + penniesMoney + dollarsMoney;
DecimalFormat currency = new DecimalFormat("$###,###.##");
if (add.isChecked())
{
if (totalMoney > 0)
{
newTotalMoney = oldTotalMoney + totalMoney;
oldTotalMoney = newTotalMoney;
results.setText(currency.format(newTotalMoney));
}
else
{
Toast.makeText(Piggy.this, "You need to do more chores!!", Toast.LENGTH_LONG).show();
}
}
if (subtract.isChecked())
{
newTotalMoney = oldTotalMoney - totalMoney;
}
if (newTotalMoney > 0)
{
oldTotalMoney = newTotalMoney;
results.setText(currency.format(newTotalMoney));
}
else
{
Toast.makeText(Piggy.this, "Save more money kido!!", Toast.LENGTH_LONG).show();
};
}
});
}
}
I have searched for an answer but they all seem to be slightly different situations. Any ideas? Thanks. And like I said, this works fine if the TextView box is overlapping the quarters EditText box.
Edit 1 Here is the screen before the piggy bank
main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<ImageView
android:id="#+id/ic_launcher_money"
android:layout_width="100px"
android:layout_height="100px"
android:layout_marginLeft="4px"
android:layout_marginRight="10px"
android:layout_marginTop="2px"
android:src="#drawable/ic_launcher_money"></ImageView>
<TextView
android:id="#+id/bankses"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#+id/bankses"
android:textSize="25sp">
</TextView>
</LinearLayout>
Main.java
package net.finalexam;
import android.app.ListActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
public class Main extends ListActivity {
#Override
public void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
String[] banks ={"Piggy Bank","Adult Bank"};
setListAdapter(new ArrayAdapter<String>(this,R.layout.main, R.id.bankses, banks));
}
protected void onListItemClick(ListView l, View v, int position, long id){
switch(position){
case 0:
startActivity(new Intent(Main.this,Piggy.class));
break;
case 1:
startActivity(new Intent(Main.this,Adultbank.class));
break;
}
}
}

Try cleaning your project on Eclipse. It often fixes that kind of problems.

NullPointerException in Android Program in onCreate()

I am fairly new to android and am writing an app that will solve physics problems. The math is going well thanks to some help from these forums, but when I try to start my activity from a list it comes up with a nullpointerexception in the onCreate Method of the new activity. This doesn't seem to make much sense though, because all thats there is a submit button that executes the math from some EditText views. Here is my code.
package android.physicsengine;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
import java.lang.Math;
public class ProjectileMotion extends Activity {
private EditText acceleration;
private EditText finalVelocity;
private EditText initialVelocity;
private EditText time;
private EditText deltay;
private EditText velocity;
private EditText deltax;
private Button submitButton;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.projectile_motion_layout);
submitButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
acceleration = (EditText)findViewById(R.id.acceleration);
double a = Doublify(acceleration);
finalVelocity = (EditText)findViewById(R.id.finalVelocity);
double vf = Doublify(finalVelocity);
initialVelocity = (EditText)findViewById(R.id.intitialVelocity);
double vi = Doublify(initialVelocity);
time = (EditText)findViewById(R.id.time);
double t = Doublify(time);
deltay = (EditText)findViewById(R.id.deltay);
double y = Doublify(deltay);
velocity = (EditText)findViewById(R.id.velocity);
double vx = Doublify(velocity);
deltax = (EditText)findViewById(R.id.deltax);
double x = Doublify(deltax);
//Y Axis
if(time.getText()==null && deltay.getText()==null){
time.setText(Double.toString((vf-vi)/a));
deltay.setText(Double.toString(((vf-vi)/a)+(a*Math.pow(((vf-vi)/a),2))));
}
if(acceleration.getText()==null && deltay.getText()==null){
acceleration.setText(Double.toString((vf-vi)/t));
deltay.setText(Double.toString((vi*t+.5*((vf-vi)/t))*Math.pow(t,2)));
}
if(acceleration.getText()==null && time.getText()==null){
acceleration.setText(Double.toString(((Math.pow(vf,2)-Math.pow(vi,2)))/2*y));
time.setText(Double.toString(2*y*(vf-vi)/(Math.pow(vf,2)-vi)));
}
if(initialVelocity.getText()==null && deltay.getText()==null){
initialVelocity.setText(Double.toString(vf-a*t));
deltay.setText(Double.toString((vf-a*t)*t+.5*a*Math.pow(t,2)));
}
if(initialVelocity.getText()==null && time.getText()==null){
initialVelocity.setText(Double.toString(Math.sqrt(Math.pow(vf,2)-2*a*y)));
time.setText(Double.toString((vf-Math.sqrt(Math.pow(vf,2)-2*a*y))/2));
}
if(initialVelocity.getText()==null && acceleration.getText()==null){
initialVelocity.setText(Double.toString(vf-2*(vf-y/t)));
acceleration.setText(Double.toString((2/t)*(vf-y/t)));
}
if(finalVelocity.getText()==null && deltay.getText()==null){
finalVelocity.setText(Double.toString(vi+a*t));
deltay.setText(Double.toString(vi*t+.5*a*Math.pow(t,2)));
}
if(finalVelocity.getText()==null && time.getText()==null){
finalVelocity.setText(Double.toString(Math.sqrt(Math.pow(vi,2)+2*a*y)));
time.setText(Double.toString(((Math.sqrt(Math.pow(vi,2)+2*a*y)-vi))/a));
}
if(finalVelocity.getText()==null && acceleration.getText()==null){
acceleration.setText(Double.toString(2*(y-vi*t)/Math.pow(t,2)));
finalVelocity.setText(Double.toString(vi+(2*(y-vi*t)/t)));
}
if(finalVelocity.getText()==null && initialVelocity.getText()==null){
initialVelocity.setText(Double.toString((y-.5*a*Math.pow(t,2))/t));
finalVelocity.setText(Double.toString((y-.5*a*Math.pow(t,2))/t)+a*t);
}
}
});
}
private double Doublify(EditText editText){
if(editText.getText()!= null){
return Double.parseDouble(editText.getText().toString());
}
return 0;
}
}
and the XML
<?xml version="1.0" encoding="utf-8"?>
<TableLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<TableRow>
<TextView android:text="Projectile Motion Engine"
android:textSize="25dip"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_span="4"
android:layout_gravity="center" />
</TableRow>
<TableRow>
<TextView android:text="X axis"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_span="2"
android:textStyle="bold"/>
<TextView android:text="Y axis"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_span="2"
android:textStyle="bold"/>
</TableRow>
<TableRow>
<TextView android:text="accel(m/s^2)="
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<EditText android:id="#+id/acceleration"
android:text="9.8"
android:inputType="numberDecimal"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<TextView android:text="deltax(m)="
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<EditText android:id="#+id/deltax"
android:inputType="numberDecimal"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
</TableRow>
<TableRow>
<TextView android:text="init v(m/s)="
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<EditText android:id="#+id/intitialVelocity"
android:inputType="numberDecimal"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<TextView android:text="v ="
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<EditText android:id="#+id/velocity"
android:inputType="numberDecimal"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
</TableRow>
<TableRow>
<TextView android:text="final v(m/s)="
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<EditText android:id="#+id/finalVelocity"
android:inputType="numberDecimal"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<TextView android:text="time(s)="
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<EditText android:id="#+id/time"
android:inputType="numberDecimal"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
</TableRow>
<TableRow>
<TextView android:text="deltay(m)="
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<EditText android:id="#+id/deltay"
android:inputType="numberDecimal"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<Button android:id="#+id/submitButton"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_span="2"
android:text="Launch" />
</TableRow>
</TableLayout>

super.onCreate(savedInstanceState);
setContentView(R.layout.projectile_motion_layout);
submitButton.setOnClickListener(new OnClickListener() {
You forgot to assign your submitButton (with findViewById)
super.onCreate(savedInstanceState);
setContentView(R.layout.projectile_motion_layout);
submitButton = (Button) findViewById((R.id.submitButton); // new line
submitButton.setOnClickListener(new OnClickListener() {

Based on the code you've posted, it appears that you call
submitButton.setOnClickListener(new OnClickListener() {
before instantiating submitButton with a value. This would cause a NullPointer

projectile_motion_layout may not be in your android manifest. I would check that first.
You can find the Application Nodes under the Application tab in the manifest.

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