예기치 않게 종료되었습니다.

Question

// 버튼을 클릭하면 Image를 10도씩 회전하는 예제입니다.

package com.example.project4_9;

import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;

public class MainActivity extends ActionBarActivity {

	Button button = (Button)findViewById(R.id.Btn);
	ImageView iv = (ImageView)findViewById(R.id.ImgDog);
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		
		button.setOnClickListener(new OnClickListener() {

			float rot = iv.getRotation();
			
			@Override
			public void onClick(View arg0) {
				iv.setRotation(rot+10);
				
			}
		});
	}
}

 

<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:orientation="vertical"
    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.project4_9.MainActivity" >

    <Button
        android:id="@+id/Btn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:drawableLeft="@drawable/emo_im_cool"
        android:drawableRight="@drawable/emo_im_cool"
        android:text="회전하기" />

    <ImageView
        android:id="@+id/ImgDog"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:layout_marginTop="60dp"
        android:rotation="0"
        android:src="@drawable/dog" />

</LinearLayout>

 

Answer 1

    Button button = (Button)findViewById(R.id.Btn);

    ImageView iv = (ImageView)findViewById(R.id.ImgDog);

 

이 부분의 호출 순서가 잘못 되었습니다.

setContentView 다음에 호출되어야 합니다.

Comments

아, 이런. 지적해 주셔서 감사합니다.