Android: app crashing after button click

Question

I new with android, I'm using Android Studio 2.2 for my coding and I'm trying to build my first app, basically the app doesn't do much or now, and then after adding a price method to the onClick method for my app, the app crashes whenever I click the button.

Below I have provided the error message and my own code.

The error message I get from my android studio is as copied from the logcat view:

10-06 09:46:00.338 30789-30789/com.example.abdulkarim.justjava E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.abdulkarim.justjava, PID: 30789
java.lang.IllegalStateException: Could not execute method for android:onClick
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:293)
at android.view.View.performClick(View.java:4660)
at android.view.View$PerformClick.run(View.java:19445)
at android.os.Handler.handleCallback(Handler.java:733)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:146)
at android.app.ActivityThread.main(ActivityThread.java:5603)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1283)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1099)
at dalvik.system.NativeStart.main(Native Method)

 Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288)
at android.view.View.performClick(View.java:4660) 
at android.view.View$PerformClick.run(View.java:19445) 
at android.os.Handler.handleCallback(Handler.java:733) 
at android.os.Handler.dispatchMessage(Handler.java:95) 
at android.os.Looper.loop(Looper.java:146) 
at android.app.ActivityThread.main(ActivityThread.java:5603) 
at java.lang.reflect.Method.invokeNative(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:515) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1283) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1099) 
at dalvik.system.NativeStart.main(Native Method) 

 Caused by: android.content.res.Resources$NotFoundException: String resource ID #0x2
at android.content.res.Resources.getText(Resources.java:1431)
at android.support.v7.widget.ResourcesWrapper.getText(ResourcesWrapper.java:52)
at android.widget.TextView.setText(TextView.java:4954)
at com.example.abdulkarim.justjava.MainActivity.display(MainActivity.java:33)
at com.example.abdulkarim.justjava.MainActivity.submit(MainActivity.java:24)
at java.lang.reflect.Method.invokeNative(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:515) 
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288) 
at android.view.View.performClick(View.java:4660) 
at android.view.View$PerformClick.run(View.java:19445) 
at android.os.Handler.handleCallback(Handler.java:733) 
at android.os.Handler.dispatchMessage(Handler.java:95) 
at android.os.Looper.loop(Looper.java:146) 
at android.app.ActivityThread.main(ActivityThread.java:5603) 
at java.lang.reflect.Method.invokeNative(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:515) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1283) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1099) 
at dalvik.system.NativeStart.main(Native Method) 
10-06 09:47:13.823 30789-30789/? I/Process: Sending signal. PID: 30789 SIG: 9

Here is my MainActivity.java code

package com.example.abdulkarim.justjava;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;

import java.text.NumberFormat;


public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    /**
     * This method is called when the order button is clicked.
     */
    public void submit(View view){
        int numberOfCoffees = 2;
        display(numberOfCoffees);
        displayPrice(numberOfCoffees * 10);
    }

    /**
     * This method displays the given quantity on the screen
     */
    private void display(int number){
        TextView quantityTextView = (TextView) findViewById(R.id.quantity_text_view);
        quantityTextView.setText(number);
    }

    /**
     * This method displays the given price on the screen
     */
    private void displayPrice(int number){
        TextView priceTextView = (TextView) findViewById(R.id.price_text_view);
        priceTextView.setText(NumberFormat.getCurrencyInstance().format(number));
    }
}

and here is my layout code from main_activity.xml

    <?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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"
    android:orientation="vertical"
    tools:context="com.example.abdulkarim.justjava.MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Quantity"
        android:textAllCaps="true"
        android:textSize="16sp"
        android:textColor="@android:color/darker_gray"
        android:layout_marginBottom="16dp"/>
    <TextView
        android:id="@+id/quantity_text_view"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="0"
        android:textSize="16sp"
        android:textColor="@android:color/black"
        android:layout_marginBottom="16dp"/>
    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Price"
        android:textAllCaps="true"
        android:textSize="16sp"
        android:textColor="@android:color/darker_gray"
        android:layout_marginBottom="16dp"/>
    <TextView
        android:id="@+id/price_text_view"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="$0"
        android:textSize="16sp"
        android:textColor="@android:color/black"
        android:layout_marginBottom="16dp"/>
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Order"
        android:textAllCaps="true"
        android:textSize="16sp"
        android:onClick="submit"/>
</LinearLayout>

Please help me find the error in my code.

Answer 1

you can not directly set integer to you Textview. Only String is allowed so update your method and it will work:

 /**
     * This method displays the given quantity on the screen
     */
    private void display(int number){
        TextView quantityTextView = (TextView) findViewById(R.id.quantity_text_view);
        quantityTextView.setText(number+"");
    }

    /**
     * This method displays the given price on the screen
     */
    private void displayPrice(int number){
        TextView priceTextView = (TextView) findViewById(R.id.price_text_view);
        priceTextView.setText(NumberFormat.getCurrencyInstance().format(number)+"");
    }