I've been trying to make a simple program that fetches a small random number and displays it to the user in a textview. After finally getting the random number to generate (I think) the program throws a fatal exception whenever I run. No errors in code, but I'm a complete newbie and I am starting simple so that I may learn. After hours I've submitted to asking for help. I'm almost certain that my snippet for random numbers is in the wrong area, I just am not sure where to put it. Everywhere I tried throws the same error.
This is the .java
package com.eai.vgp;
import java.util.Random;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.TextView;
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
Random pp = new Random();
int a1 = pp.nextInt(10);
TextView tv = (TextView)findViewById(R.id.tv);{
tv.setText(a1);}
}
The 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"
tools:context=".MainActivity" >
<TextView
android:id="@+id/tv"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true" />
</RelativeLayout>
LogCat
03-03 16:34:25.313: I/Process(740): Sending signal. PID: 740 SIG: 9
03-03 16:35:02.212: E/Trace(806): error opening trace file: No such file or directory (2)
03-03 16:35:02.802: W/ResourceType(806): No package identifier when getting value for resource number 0x00000001
03-03 16:35:02.813: D/AndroidRuntime(806): Shutting down VM
03-03 16:35:02.813: W/dalvikvm(806): threadid=1: thread exiting with uncaught exception (group=0x40a13300)
03-03 16:35:02.833: E/AndroidRuntime(806): FATAL EXCEPTION: main
03-03 16:35:02.833: E/AndroidRuntime(806): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.eai.vgp/com.eai.vgp.MainActivity}: android.content.res.Resources$NotFoundException: String resource ID #0x1
03-03 16:35:02.833: E/AndroidRuntime(806): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059)
03-03 16:35:02.833: E/AndroidRuntime(806): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
03-03 16:35:02.833: E/AndroidRuntime(806): at android.app.ActivityThread.access$600(ActivityThread.java:130)
03-03 16:35:02.833: E/AndroidRuntime(806): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
03-03 16:35:02.833: E/AndroidRuntime(806): at android.os.Handler.dispatchMessage(Handler.java:99)
03-03 16:35:02.833: E/AndroidRuntime(806): at android.os.Looper.loop(Looper.java:137)
03-03 16:35:02.833: E/AndroidRuntime(806): at android.app.ActivityThread.main(ActivityThread.java:4745)
03-03 16:35:02.833: E/AndroidRuntime(806): at java.lang.reflect.Method.invokeNative(Native Method)
03-03 16:35:02.833: E/AndroidRuntime(806): at java.lang.reflect.Method.invoke(Method.java:511)
03-03 16:35:02.833: E/AndroidRuntime(806): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
03-03 16:35:02.833: E/AndroidRuntime(806): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
03-03 16:35:02.833: E/AndroidRuntime(806): at dalvik.system.NativeStart.main(Native Method)
03-03 16:35:02.833: E/AndroidRuntime(806): Caused by: android.content.res.Resources$NotFoundException: String resource ID #0x1
03-03 16:35:02.833: E/AndroidRuntime(806): at android.content.res.Resources.getText(Resources.java:229)
03-03 16:35:02.833: E/AndroidRuntime(806): at android.widget.TextView.setText(TextView.java:3620)
03-03 16:35:02.833: E/AndroidRuntime(806): at com.eai.vgp.MainActivity.onCreate(MainActivity.java:22)
03-03 16:35:02.833: E/AndroidRuntime(806): at android.app.Activity.performCreate(Activity.java:5008)
03-03 16:35:02.833: E/AndroidRuntime(806): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079)
03-03 16:35:02.833: E/AndroidRuntime(806): atandroid.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023)
03-03 16:35:02.833: E/AndroidRuntime(806): ... 11 more
03-03 16:35:05.113: I/Process(806): Sending signal. PID: 806 SIG: 9
You are trying to set int value to
TextView
so you are getting this issue. To solve this try below one optionoption 1:
Option2:
This will resolve your problem.
Other possible solution:
a.setText(String.valueOf(x))
that was the exact solution to the problem with my case.
Move
To inside
onCreate()
, and changetv.setText(a1);
totv.setText(String.valueOf(a1));
:First issue:
findViewById()
was called beforeonCreate()
, which would throw an NPE.Second issue: Passing an int directly to a TextView calls the overloaded method that looks for a String resource (from
R.string
). Therefore, we want to useString.valueOf()
to force theString
overloaded method.