Unknown error with Android: 2.3.3 - error "application...stopped unexpectedly
Java code:
package wip.test.app1;
import android.app.Activity;
import android.os.Bundle;
import android.widget.RadioButton;
import android.widget.TextView;
import java.util.Random;
public class WIPTEST extends Activity {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
while(true)
{
Random generate = new Random();
int seed = generate.nextInt(4);
//QUESTIONS
String question[] = new String[4];
question[0]="Who is the current president of the United States?";
question[1]="Who is the current president of the United States?";
question[2]="Who is the current president of the United States?";
question[3]="Who is the current president of the United States?";
//ANSWERS
//CN: answer[corresponding question][question number]
String answer[][] = new String[4][4];
answer[0][0]="George W. Bush";
answer[0][1]="Barrack Obama";
answer[0][2]="Chuck Norris";
answer[0][3]="George Washington";
answer[1][0]="George W. Bush";
answer[1][1]="Barrack Obama";
answer[1][2]="Chuck Norris";
answer[1][3]="George Washington";
answer[2][0]="George W. Bush";
answer[2][1]="Barrack Obama";
answer[2][2]="Chuck Norris";
answer[2][3]="George Washington";
answer[3][0]="George W. Bush";
开发者_C百科 answer[3][1]="Barrack Obama";
answer[3][2]="Chuck Norris";
answer[3][3]="George Washington";
//CORRECT_ANSWERS
int correct[] = new int[4];
correct[0]=1;
correct[1]=2;
correct[2]=2;
correct[3]=2;
TextView tv = (TextView) findViewById(R.id.tv);
tv.setText(question[seed]);
RadioButton a = (RadioButton) findViewById(R.id.a);
RadioButton b = (RadioButton) findViewById(R.id.b);
RadioButton c = (RadioButton) findViewById(R.id.c);
RadioButton d = (RadioButton) findViewById(R.id.d);
a.setText(answer[seed][0]);
b.setText(answer[seed][1]);
c.setText(answer[seed][2]);
d.setText(answer[seed][3]);
setContentView(R.layout.main);
}
}
}
Note: these are sample questions
XML:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="@+id/tv"
android:textSize="15sp"
/>
<RadioGroup>
<RadioButton
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="@+id/a"
/>
<RadioButton
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="@+id/b"
/>
<RadioButton
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="@+id/c"
/>
<RadioButton
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="@+id/d"
/>
</RadioGroup>
</LinearLayout>
Eclipse does not give any errors on the java code or on the xml but when i run it on the emulator (2.3.3) it gives an error
The application (process wip.test.app1) has stopped unexpectedly. Please try again.
I have tried multiple times including changing the code to be only in the one function and not in different functions. Also, I am somewhat unfamiliar with the Android SDK, but I am capable in both C++ and Java.
you should not be looping forever in onCreate creating and initializing all those objects. Also findViewById must be called after setting a view
At first glance I'd say it's because
setContentView(R.layout.main);
needs to be place before any call such as
TextView tv = (TextView) findViewById(R.id.tv);
So your code should be
setContentView(R.layout.main);
TextView tv = (TextView) findViewById(R.id.tv);
tv.setText(question[seed]);
RadioButton a = (RadioButton) findViewById(R.id.a);
RadioButton b = (RadioButton) findViewById(R.id.b);
RadioButton c = (RadioButton) findViewById(R.id.c);
RadioButton d = (RadioButton) findViewById(R.id.d);
a.setText(answer[seed][0]);
b.setText(answer[seed][1]);
c.setText(answer[seed][2]);
d.setText(answer[seed][3]);
There may be other things though...
You need to call setContentView(R.layout.main)
before you make any findViewById()
calls. Your activity has no views until you do that. It's a good practice to call it immediately after the call to super.onCreate()
.
精彩评论