imageView中的图像加载变为黑色 [英] Image load in imageView from gallery become black

问题描述

所以我从厨房加载图像并显示到 ImageView ，图像变为黑色。但不是所有的图像，只是一定的。为什么会发生这种情况？

So I load image from galley and display into ImageView, the image turn to black. But not all images, just a certain. Why would this happen?

 @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        switch (requestCode) {

        case RESULT_LOAD_IMAGE:
            if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK & null != data) {
                imageUri = data.getData();
                imageView.setImageURI(imageUri);
            }
            break;
         }
     }

然后我尝试了这种方法。图像显示但看起来很模糊。

Then I tried this method. The image show but look blurry.

 imageView.setImageBitmap(decodeUri(imageUri));

 private Bitmap decodeUri(Uri selectedImage) throws FileNotFoundException {
        BitmapFactory.Options o = new BitmapFactory.Options();
        o.inJustDecodeBounds = true;
        BitmapFactory.decodeStream(
                getContentResolver().openInputStream(selectedImage), null, o);

        final int REQUIRED_SIZE = 100;

        int width_tmp = o.outWidth, height_tmp = o.outHeight;
        int scale = 1;
        while (true) {
            if (width_tmp / 2 < REQUIRED_SIZE || height_tmp / 2 < REQUIRED_SIZE) {
                break;
            }
            width_tmp /= 2;
            height_tmp /= 2;
            scale *= 2;
        }

        BitmapFactory.Options o2 = new BitmapFactory.Options();
        o2.inSampleSize = scale;
        return BitmapFactory.decodeStream(
                getContentResolver().openInputStream(selectedImage), null, o2);
    }

推荐答案

是的，它发生在<$无法加载c $ c>位图，因为图像的高度和宽度较大， 2048 * 2048 。通过相机拍摄的图像通常很大，因此，最好调整图像大小。

Yes it happens when Bitmap can't be loaded because the height and width of the image is larger in size which is 2048*2048. Images captured through camera are usually large in size so, It is good practice to resize the image.

以下只是裁剪图像的示例，并没有照顾图像比率

public class InputImageCompressor extends Activity{

public static void compressInputImage(Intent data, Context context, ImageView newIV)
{
    Bitmap bitmap;
    Uri inputImageData = data.getData();
    try
    {
        Bitmap bitmapInputImage = MediaStore.Images.Media.getBitmap(context.getContentResolver(), inputImageData);
        if (bitmapInputImage.getWidth() > 2048 && bitmapInputImage.getHeight() > 2048)
        {
            bitmap = Bitmap.createScaledBitmap(bitmapInputImage, 1024, 1280, true);
            newIV.setImageBitmap(bitmap);
        }
        else if (bitmapInputImage.getWidth() > 2048 && bitmapInputImage.getHeight() < 2048)
        {
            bitmap = Bitmap.createScaledBitmap(bitmapInputImage, 1920, 1200, true);
            newIV.setImageBitmap(bitmap);
        }
        else if (bitmapInputImage.getWidth() < 2048 && bitmapInputImage.getHeight() > 2048)
        {
            bitmap = Bitmap.createScaledBitmap(bitmapInputImage, 1024, 1280, true);
            newIV.setImageBitmap(bitmap);
        }
        else if (bitmapInputImage.getWidth() < 2048 && bitmapInputImage.getHeight() < 2048)
        {
            bitmap = Bitmap.createScaledBitmap(bitmapInputImage, bitmapInputImage.getWidth(), bitmapInputImage.getHeight(), true);
            newIV.setImageBitmap(bitmap);
        }
    } catch (Exception e)
    {
        Toast.makeText(context, e.toString(), Toast.LENGTH_LONG).show();
    }
   }
}

在<$中使用此项c $ c> onActivityResult as：

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    switch (requestCode) {

    case RESULT_LOAD_IMAGE:
        if (requestCode == RESULT_LOAD_IMAGE && resultCode == RESULT_OK & null != data) {
             InputImageCompressor.compressInputImage(data, your_activity_context.this, imageView);
        }
        break;
     }
 }

这篇关于imageView中的图像加载变为黑色的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！