java - 我想在Android Studio中制作一个总统审查应用程序，其中包含每个总统的照片，但是我一直在收到OutOfMemoryError

我刚刚启动Android Studio，对Java也有些陌生，所以请原谅效率低下的代码。

无论如何，当我单击应用程序上的主要活动上的按钮以将用户带到要显示图像的活动时，我的应用程序停止工作，并引发OutOfMemoryError。

这是MainActivty.java：

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    Button presidentQuizButton = (Button) findViewById(R.id.presidentQuizButton);
    Button reviewPresidentsButton = (Button) findViewById(R.id.reviewPresidentsButton);

    presidentQuizButton.setOnClickListener(new Button.OnClickListener(){
        public void onClick(View v){
            //when button is clicked, do something
        }
    });
    reviewPresidentsButton.setOnClickListener(new Button.OnClickListener(){
        public void onClick(View v){
            //when button is clicked, do something
            startActivity(new Intent(MainActivity.this, presidentReviewActivity.class));
        }
    });

}

这是PresidentReviewActivity.java：

ImageView imageView;
    public int presidentNumber = 0;

    private Drawable drawable;
    private Drawable [] drawables = null;

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

        Button menuButton = (Button) findViewById(R.id.menuButton);
        Button nextButton = (Button) findViewById(R.id.nextButton);
        Button backButton = (Button) findViewById(R.id.backButton);

        drawables = new Drawable[]{
                getResources().getDrawable(R.drawable.president1),
                getResources().getDrawable(R.drawable.president2),
                getResources().getDrawable(R.drawable.president3),
                getResources().getDrawable(R.drawable.president4),
                getResources().getDrawable(R.drawable.president5),
                getResources().getDrawable(R.drawable.president6),
                getResources().getDrawable(R.drawable.president7),
                getResources().getDrawable(R.drawable.president8),
                getResources().getDrawable(R.drawable.president9),
                getResources().getDrawable(R.drawable.president10),
                getResources().getDrawable(R.drawable.president11),
                getResources().getDrawable(R.drawable.president12),
                getResources().getDrawable(R.drawable.president13),
                getResources().getDrawable(R.drawable.president14),
                getResources().getDrawable(R.drawable.president15),
                getResources().getDrawable(R.drawable.president16),
                getResources().getDrawable(R.drawable.president17),
                getResources().getDrawable(R.drawable.president18),
                getResources().getDrawable(R.drawable.president19),
                getResources().getDrawable(R.drawable.president20),
                getResources().getDrawable(R.drawable.president21),
                getResources().getDrawable(R.drawable.president22),
                getResources().getDrawable(R.drawable.president23),
                getResources().getDrawable(R.drawable.president24),
                getResources().getDrawable(R.drawable.president25),
                getResources().getDrawable(R.drawable.president26),
                getResources().getDrawable(R.drawable.president27),
                getResources().getDrawable(R.drawable.president28),
                getResources().getDrawable(R.drawable.president29),
                getResources().getDrawable(R.drawable.president30),
                getResources().getDrawable(R.drawable.president31),
                getResources().getDrawable(R.drawable.president32),
                getResources().getDrawable(R.drawable.president33),
                getResources().getDrawable(R.drawable.president34),
                getResources().getDrawable(R.drawable.president35),
                getResources().getDrawable(R.drawable.president36),
                getResources().getDrawable(R.drawable.president37),
                getResources().getDrawable(R.drawable.president38),
                getResources().getDrawable(R.drawable.president39),
                getResources().getDrawable(R.drawable.president40),
                getResources().getDrawable(R.drawable.president41),
                getResources().getDrawable(R.drawable.president42),
                getResources().getDrawable(R.drawable.president43),
                getResources().getDrawable(R.drawable.president44),
        };

        menuButton.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View v) {
                finish();
            }
        });

        nextButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                presidentNumber++;
                drawable = drawables[presidentNumber];
                imageView.setImageDrawable(drawable);
            }
        });

这是大多数错误日志：

http://imgur.com/xzFfPrq

最佳答案

而不是将所有可绘制内容存储在数组中。您实际上可以只将资源ID存储在数组中。


将private Drawable [] drawables = null;替换为private int[] drawableids
将drawables = new Drawable[]{...}替换为drawableids = new int[]{...}
更换

drawable = drawables[presidentNumber];
imageView.setImageDrawable(drawable);

至

drawable = getResource().getDrawable(drawableids[presidentNumber]);
imageView.setImageDrawable(drawable);

尝试按上述步骤进行更改，然后重试。
nullpointerexception可能是由于您没有初始化drawableids数组或您仍在使用drawables数组而不是drawableids引起的。