Android画廊显示来自SDcard的图像

Question

这是我的图库程序,我在其中显示静态文件的内容,如何修改此程序以显示SD卡中的照片,如果没有照片或SD卡发出警报

 package DisplayViewsExample.com;

import android.app.Activity;
import android.os.Bundle;
import android.content.Context;
import android.content.res.TypedArray;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.Gallery;
import android.widget.ImageView;
import android.widget.Toast;
import android.widget.AdapterView.OnItemClickListener;




   public class DisplayViewsExampleActivity extends Activity {

 Integer[] imageIDs = {
            R.drawable.sample_1,
            R.drawable.sample_2,
            R.drawable.sample_3

    };

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    Gallery gallery = (Gallery) findViewById(R.id.gallery1);

    gallery.setAdapter(new ImageAdapter(this));        
    gallery.setOnItemClickListener(new OnItemClickListener() 
    {
        public void onItemClick(AdapterView parent, 
        View v, int position, long id) 
        {                
    /*        Toast.makeText(getBaseContext(), 
                    "pic" + (position + 1) + " selected", 
                    Toast.LENGTH_SHORT).show();*/
            ImageView imageView = (ImageView) findViewById(R.id.image1);                
            imageView.setImageResource(imageIDs[position]);

        }
    });

}
public class ImageAdapter extends BaseAdapter 
{
    private Context context;
    private int itemBackground;

    public ImageAdapter(Context c) 
    {
        context = c;
        //---setting the style---
        TypedArray a = obtainStyledAttributes(R.styleable.Gallery1);
        itemBackground = a.getResourceId(
            R.styleable.Gallery1_android_galleryItemBackground, 0);
        a.recycle();                    
    }

    //---returns the number of images---
    public int getCount() {
        return imageIDs.length;
    }

    //---returns the ID of an item--- 
    public Object getItem(int position) {
        return position;
    }            

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

    //---returns an ImageView view---
    public View getView(int position, View convertView, ViewGroup parent) {
        ImageView imageView = new ImageView(context);
        imageView.setImageResource(imageIDs[position]);
        imageView.setScaleType(ImageView.ScaleType.FIT_XY);
        imageView.setLayoutParams(new Gallery.LayoutParams(150, 120));
        imageView.setBackgroundResource(itemBackground);
        return imageView;
    }


}    

}

Answer 1

这

Environment.getExternalStoragePublicDirectory(String type)

功能使您可以访问外部存储。甚至还有最常用的标准文件夹名称的内容。

不要忘记将访问权限放在清单上。