Android - 点击全屏图片

Question

我有一个GridView，其中包含一些点击时全屏显示的图片。

但是当我点击图片时Target must not be null的应用程序崩溃:(

我的活动：

public class ArenaActivity extends ActionBarActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_arena);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);

        GridView gv = (GridView) findViewById(R.id.grid_view);
        gv.setAdapter(new ArenaGridViewAdapter(this));
        gv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
                Intent i = new Intent(ArenaActivity.this, ArenaViewActivity.class);
                i.putExtra("position", position);
                startActivity(i);
            }
        });
    }
}

我的适配器：

public class ArenaGridViewAdapter extends BaseAdapter {
    private Context context = null;

    public ArenaGridViewAdapter(Context context) {
        this.context = context;
    }

    public int[] arenaImgs = {
            R.drawable.ic_arena_01,
            R.drawable.ic_arena_02,
            R.drawable.ic_arena_03,
            R.drawable.ic_arena_04,
            R.drawable.ic_arena_05,
            R.drawable.ic_arena_06
    };

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        SquaredImageView view = (SquaredImageView) convertView;
        if (view == null) {
            view = new SquaredImageView(context);
            view.setScaleType(CENTER_CROP);
        }

        Picasso.with(this.context) //
                .load(arenaImgs[position]) //
                .placeholder(R.drawable.ic_placeholder) //
                .error(R.drawable.ic_error) //
                .fit() //
                .into(view);

        return view;
    }

    @Override
    public int getCount() {
        return arenaImgs.length;
    }

    @Override
    public Object getItem(int arg0) {
        return null;
    }

    @Override
    public long getItemId(int arg0) {
        return 0;
    }
}

最后是全屏：

public class ArenaViewActivity extends ActionBarActivity {
    public int[] arenaImgs = {
            R.drawable.ic_arena_01,
            R.drawable.ic_arena_02,
            R.drawable.ic_arena_03,
            R.drawable.ic_arena_04,
            R.drawable.ic_arena_05,
            R.drawable.ic_arena_06
    };

    private ShareActionProvider mShareActionProvider;
    private int urlshare;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_arena);
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);

        Intent i = getIntent();
        int position = i.getExtras().getInt("position");
        this.urlshare = position;

        ImageView iv = (ImageView) findViewById(R.id.arena_full_view);
        Picasso.with(getApplicationContext())
                .load(arenaImgs[position])
                .fit()
                .centerCrop()
                .into(iv);
    }
}

错误日志表明目标null位于：Picasso.with(getApplicationContext())

我解决了这个问题。全屏布局出错。

更改为：setContentView（R.layout.arena_full_view）;

谢谢大家。