java 如何将 URI 转换为位图？
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How to convert URI to bitmap?
提问by Pigeon App
I Am Making An Image Filter App And Before Applying Filter I Will Crop The Image As Square, I Can Crop The Image Using Soundcloud Library Like This:-
我正在制作一个图像过滤器应用程序，在应用过滤器之前，我将图像裁剪为正方形，我可以像这样使用 Soundcloud 库裁剪图像：-
private void beginCrop(String sources) {
img_name = "cropped"+System.currentTimeMillis();
Uri destination = Uri.fromFile(new File(getCacheDir(), "cropped"+System.currentTimeMillis()));
Uri source = Uri.parse("file://"+sources);
Crop.of(source, destination).withAspect(200,200).start(this);
}
private void handleCrop(int resultCode, Intent result) {
if (resultCode == RESULT_OK) {
Toast.makeText(this,Crop.getOutput(result).toString(), Toast.LENGTH_SHORT).show();
Intent intent = new Intent(AlbumActivity.this,FilterImageActivity
.class);
intent.putExtra("output_image",Crop.getOutput(result).toString());
startActivity(intent);
} else if (resultCode == Crop.RESULT_ERROR) {
Toast.makeText(this, Crop.getError(result).getMessage(), Toast.LENGTH_SHORT).show();
}
}}
And On The Next Activity Which Is FilterImageActivity.java:-
在下一个活动是 FilterImageActivity.java:-
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_filter_image);
String uri = getIntent().getStringExtra("output_image");
setImageDir(uri);
}
And The Function setImageDir():-
和函数 setImageDir():-
private void setImageDir(String uri)
{
Bitmap bitmap = convetBitmap(uri);
// clear bitmap memory
/* originalImage.recycle();
finalImage.recycle();
finalImage.recycle();*/
originalImage = bitmap.copy(Bitmap.Config.ARGB_8888, true);
filteredImage = originalImage.copy(Bitmap.Config.ARGB_8888, true);
finalImage = originalImage.copy(Bitmap.Config.ARGB_8888, true);
imagePreview.setImageBitmap(originalImage);
bitmap.recycle();
// render selected image thumbnails
filtersListFragment.prepareThumbnail(originalImage);
}
And The Function convertBitmap():-
和函数 convertBitmap():-
private Bitmap convetBitmap(final String uri)
{
final Bitmap[] bitmap = {null};
Thread task = new Thread()
{
@Override
public void run()
{
try {
bitmap[0] = Glide.with(getApplicationContext()).asBitmap().load(Uri.parse(uri)).into(100,100).get();
} catch (InterruptedException | ExecutionException e) {
e.printStackTrace();
}
}
};
task.start();
return bitmap[0];
}
}
Image Is Cropped And Saved To Directory For Example
例如，图像被裁剪并保存到目录
file:///data/user/0/com.dev.pigeon/cache/cropped1518332591373
file:///data/user/0/com.dev.pigeon/cache/cropped1518332591373
But It Gives An Error
但它给出了一个错误
Attempt to invoke virtual method 'android.graphics.Bitmap android.graphics.Bitmap.copy(android.graphics.Bitmap$Config, boolean)' on a null object reference
Maybe The URI is Not Converting Into Bitmap Please Any Solution???
也许 URI 没有转换成位图，请问有什么解决方案？？？
回答by Koushik Mondal
To convert URI to the bitmap you can do as follows.
要将 URI 转换为位图，您可以执行以下操作。
try {
if( Uri.parse(paths)!=null ){
Bitmap bitmap = MediaStore.Images.Media.getBitmap(c.getContentResolver() , Uri.parse(paths));
}
}
catch (Exception e) {
//handle exception
}
When you are getting file form file picker or camera intent then you can do this.
当您获得文件格式文件选择器或相机意图时，您可以执行此操作。
protected void onActivityResult(int requestCode, int resultCode, Intent data)
{
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK)
{
Uri imageUri = data.getData();
Bitmap bitmap = MediaStore.Images.Media.getBitmap(this.getContentResolver(), imageUri);
}
}
