Question

我正在尝试从SD卡中获取图像并在gridView中显示。

这是我的列表视图

private void SetListView() {
    CustomListViewValuesArr = new ArrayList<PhotoModel>();
    if (mediaStorageDir.isDirectory()) {
        listFile = mediaStorageDir.listFiles();

        for (int i = 0; i < listFile.length; i++) {
            String path=listFile[i].getAbsolutePath();
            if(path.contains(saveId)){
            PhotoModel listItems = new PhotoModel();
            listItems.setPhoto(listFile[i].getAbsolutePath());
            CustomListViewValuesArr.add(listItems);
            listItems = new PhotoModel();
            }
        }
        adapter = new Photo_Grid_Adapter(getActivity(), CustomListViewValuesArr);
        photoGrid.setNumColumns(2);
        photoGrid.setAdapter(adapter);
        photoGrid.setExpanded(true);
    }
}

这是我的适配器getview

Picasso.with(activity)
.load(pendingTask.getPhoto())
.transform(new CircleTransform()).resize(100, 100)
.error(R.drawable.icon_no_preview).into(holder.photo_imageView);

但在这里我无法设置图像。它始终显示icon_no_preview。

我正在走这条道路。

/storage/emulated/0/Pictures/Project/IMG_20151013_181311id_5.jpg

即使我像这样硬着适配器中的值。

Picasso.with(activity)
.load("/storage/emulated/0/Pictures/Project/IMG_20151013_181311id_5.jpg")
.transform(new CircleTransform()).resize(100, 100)
.error(R.drawable.icon_no_preview).into(holder.photo_imageView);

但它没有在gridView中显示图像。

Answer 1

试试这个：

java代码：

yourclass extends Activity {

    public class ImageAdapter extends BaseAdapter {

     private Context mContext;
     ArrayList<String> itemList = new ArrayList<String>();

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

     void add(String path){
      itemList.add(path); 
     }

  @Override
  public int getCount() {
   return itemList.size();
  }

  @Override
  public Object getItem(int arg0) {
   // TODO Auto-generated method stub
   return null;
  }

  @Override
  public long getItemId(int position) {
   // TODO Auto-generated method stub
   return 0;
  }

  @Override
  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(220, 220));
             imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
             imageView.setPadding(8, 8, 8, 8);
         } else {
             imageView = (ImageView) convertView;
         }

         Bitmap bm = decodeSampledBitmapFromUri(itemList.get(position), 220, 220);

         imageView.setImageBitmap(bm);
         return imageView;
  }

  public Bitmap decodeSampledBitmapFromUri(String path, int reqWidth, int reqHeight) {

   Bitmap bm = null;
   // First decode with inJustDecodeBounds=true to check dimensions
   final BitmapFactory.Options options = new BitmapFactory.Options();
   options.inJustDecodeBounds = true;
   BitmapFactory.decodeFile(path, options);

   // Calculate inSampleSize
   options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);

   // Decode bitmap with inSampleSize set
   options.inJustDecodeBounds = false;
   bm = BitmapFactory.decodeFile(path, options); 

   return bm;   
  }

  public int calculateInSampleSize(

   BitmapFactory.Options options, int reqWidth, int reqHeight) {
   // Raw height and width of image
   final int height = options.outHeight;
   final int width = options.outWidth;
   int inSampleSize = 1;

   if (height > reqHeight || width > reqWidth) {
    if (width > height) {
     inSampleSize = Math.round((float)height / (float)reqHeight);    
    } else {
     inSampleSize = Math.round((float)width / (float)reqWidth);    
    }   
   }

   return inSampleSize;    
  }

 }

    ImageAdapter myImageAdapter;

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

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

        String ExternalStorageDirectoryPath = Environment
          .getExternalStorageDirectory()
          .getAbsolutePath();

        String targetPath = ExternalStorageDirectoryPath + "/test/";

        Toast.makeText(getApplicationContext(), targetPath, Toast.LENGTH_LONG).show();
        File targetDirector = new File(targetPath);

        File[] files = targetDirector.listFiles();
        for (File file : files){
         myImageAdapter.add(file.getAbsolutePath());
        } 
    }

}

XML布局代码：

    <GridView
        android:id="@+id/gridview"
        android:layout_width="fill_parent" 
        android:layout_height="fill_parent"
        android:columnWidth="90dp"
        android:numColumns="auto_fit"
        android:verticalSpacing="10dp"
        android:horizontalSpacing="10dp"
        android:stretchMode="columnWidth"
        android:gravity="center"/>

</LinearLayout>

Answer 2

我想你应该试试..

Picasso.with(activity)
.load(new File("/storage/emulated/0/Pictures/Project/IMG_20151013_181311id_5.jpg"))
.transform(new CircleTransform()).resize(100, 100)
.error(R.drawable.icon_no_preview).into(holder.photo_imageView);

如何从SD卡获取图像并在gridView中显示

2 个答案: