我需要只使用文件名来显示图像,而不是使用资源id。

ImageView imgView = new ImageView(this);
imgView.setBackgroundResource(R.drawable.img1);

我在可绘制文件夹中有图像img1。我想展示文件中的图像。

我该怎么做呢?


当前回答

       public static Bitmap decodeFile(String path) {
    Bitmap b = null;
    File f = new File(path);
    // Decode image size
    BitmapFactory.Options o = new BitmapFactory.Options();
    o.inJustDecodeBounds = true;

    FileInputStream fis = null;
    try {
        fis = new FileInputStream(f);
        BitmapFactory.decodeStream(fis, null, o);
        fis.close();

        int IMAGE_MAX_SIZE = 1024; // maximum dimension limit
        int scale = 1;
        if (o.outHeight > IMAGE_MAX_SIZE || o.outWidth > IMAGE_MAX_SIZE) {
            scale = (int) Math.pow(2, (int) Math.round(Math.log(IMAGE_MAX_SIZE / (double) Math.max(o.outHeight, o.outWidth)) / Math.log(0.5)));
        }

        // Decode with inSampleSize
        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize = scale;

        fis = new FileInputStream(f);
        b = BitmapFactory.decodeStream(fis, null, o2);
        fis.close();

    } catch (Exception e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

    return b;
}

public static Bitmap showBitmapFromFile(String file_path)
{
    try {
        File imgFile = new  File(file_path);
        if(imgFile.exists()){

            Bitmap pic_Bitmap = decodeFile(file_path);
            return pic_Bitmap;

        }
    } catch (Exception e) {
        MyLog.e("Exception showBitmapFromFile");
        return null;
    }
    return null;
}   

如果你在列表视图中使用图像加载,那么使用Aquery概念。

https://github.com/AshishPsaini/AqueryExample

     AQuery  aq= new AQuery((Activity) activity, convertView);
            //load image from file, down sample to target width of 250 pixels .gi 
    File file=new File("//pic/path/here/aaaa.jpg");
    if(aq!=null)
    aq.id(holder.pic_imageview).image(file, 250);

其他回答

private void showImage(ImageView img, String absolutePath) {
  
    BitmapFactory.Options options = new BitmapFactory.Options();
    options.inSampleSize = 8;
    Bitmap bitmapPicture = BitmapFactory.decodeFile(absolutePath);
    img.setImageBitmap(bitmapPicture);

}

Labeeb是对的,为什么你需要设置图像使用路径,如果你的资源已经放在资源文件夹,

只有当图像存储在SD-Card中时,才需要这种路径。

尝试下面的代码来设置存储在sd卡中的文件中的位图图像。

File imgFile = new  File("/sdcard/Images/test_image.jpg");

if(imgFile.exists()){

    Bitmap myBitmap = BitmapFactory.decodeFile(imgFile.getAbsolutePath());

    ImageView myImage = (ImageView) findViewById(R.id.imageviewTest);

    myImage.setImageBitmap(myBitmap);

}

并将此权限包含在manifest文件中:

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
mageView.setImageResource(R.id.img);

我想你可以用这个

Bitmap bmImg = BitmapFactory.decodeFile("path of your img1");
imageView.setImageBitmap(bmImg);

使用位图可以很容易地做到这一点。你可以在下面找到代码:

ImageView imageView=findViewById(R.id.imageView);

Bitmap bitMapImage= BitmapFactory.decodeFile("write path of your image");

imageView.setImageBitmap(bitMapImage);