如何显示图像的完整大小?

时间:2012-09-18 09:59:40

标签: android image gridview

我是新手,也是Android编程新手。我在互联网网站上找到了这个例子(下面是例子),这是一个很棒的教程!我想要实现的是当我在GridView上单击一张图片时,我想要显示图像的完整大小。

public class MainActivity 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());
    }
}

}

1 个答案:

答案 0 :(得分:0)

将图像传递给其他活动,以全屏显示。

传递主活动中的图像。请使用以下代码:

gridview.setOnItemClickListener(new OnItemClickListener() {
            public void onItemClick(AdapterView<?> parent, View v,
                    int position, long id) {

ImageView img = ia.getView(position, v, parent);
                img.buildDrawingCache(); 
                Bitmap bmap = img.getDrawingCache();
                Intent intent = new Intent(HelloGridView.this,
                        Imageviewer.class);
                Bundle bundle = new Bundle();
                //bundle.putParcelable("image", bmap);
                    String par=myimageadpter.getpath(position);
                             bundle.putParcelable("imagepath", par);
                intent.putExtras(bundle);
                startActivityForResult(intent, 0);

            }
        });

在其他活动中,使用此代码显示传递的图像:

 Bundle bundle = this.getIntent().getExtras();
             bmp=bundle.getParcelable("image");
            ImageView img=(ImageView) findViewById(R.id.imageView1);
            d =new BitmapDrawable(bmp);
            img.setImageBitmap(bmp);

如果你传递路径。第二项活动如下:

 Bundle bundle = this.getIntent().getExtras();

String s=bundle.getParcelable("imagepath");
 Bitmap Imagefrompath = BitmapFactory.decodeFile(s);
            ImageView img=(ImageView) findViewById(R.id.imageView1);

            img.setImageBitmap(Imagefrompath );