Android image gallery is very slow

Question

I'm starting with android and following some tutorials on web. I'm trying to create an android gallery image and it works, but only if the image that i put in drawable folder are small. If i put inside it images with a bigger size and better quality my gallery go really slow.What i have to do?

Main Activity:

public class MainActivity extends AppCompatActivity {

@Override

public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    GridView gridview = (GridView) findViewById(R.id.gridview);
    gridview.setAdapter(new ImageAdapter(this));

    gridview.setOnItemClickListener(new AdapterView.OnItemClickListener() {
        public void onItemClick(AdapterView<?> parent, View v,
                                int position, long id) {
            Toast.makeText(MainActivity.this, "" + position,
                    Toast.LENGTH_SHORT).show();
        }
    });
}

ImageAdapter:

public class ImageAdapter extends BaseAdapter {
private Context mContext;

public ImageAdapter(Context c) {
    mContext = c;
}

public int getCount() {
    return mThumbIds.length;
}

public Object getItem(int position) {
    return null;
}

public long getItemId(int position) {
    return 0;
}

// create a new ImageView for each item referenced by the Adapter
public View getView(int position, View convertView, ViewGroup parent) {
    ImageView imageView;
    if (convertView == null) {
        // if it's not recycled, initialize some attributes
        imageView = new ImageView(mContext);
        imageView.setLayoutParams(new GridView.LayoutParams(300, 300));
        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
        imageView.setPadding(4, 4, 4, 4);
    } else {
        imageView = (ImageView) convertView;
    }

    imageView.setImageResource(mThumbIds[position]);
    return imageView;
}



// references to our images
private Integer[] mThumbIds = {



        R.drawable.sample_2, R.drawable.sample_3,
        R.drawable.sample_4, R.drawable.sample_5,
        R.drawable.sample_6, R.drawable.sample_7,
        R.drawable.sample_0, R.drawable.sample_1,
        R.drawable.sample_2, R.drawable.sample_3,
        R.drawable.sample_4, R.drawable.sample_5,
        R.drawable.sample_6, R.drawable.sample_7,
        R.drawable.sample_0, R.drawable.sample_1,
        R.drawable.sample_2, R.drawable.sample_3,
        R.drawable.sample_4, R.drawable.sample_5,
        R.drawable.sample_6, R.drawable.sample_7
};

Thanks to everyone that will help me.

Answer 1

welcome to android world.

You should try using ViewHolder pattern.

Please take a look at this tutorial.

good tutorial for viewholder pattern

Answer 2

您只需要加载这些图像的缩略图并将其加载到网格中，请阅读有关在互联网和教程上创建和缓存缩略图的更多信息。当用户单击该缩略图（即特定的网格位置）时，您应该加载原始图像并显示它。尝试毕加索图书馆，将为您提供帮助