我该如何在Android中编程实现图像的裁剪和旋转？

Question

我希望能够通过编程在Android上将图像旋转90度，并裁剪从手机相册中取出的图像。请问如何实现这个操作？

- user612554

Answer 1

您可以使用以下代码来执行图像的旋转：

Bitmap bMap = BitmapFactory.decodeResource(getResources(),R.drawable.test);
Matrix mat = new Matrix();
mat.postRotate(90);
Bitmap bMapRotate = Bitmap.createBitmap(bMap, 0, 0,
                             bMap.getWidth(), bMap.getHeight(), mat, true);
BitmapDrawable bmd = new BitmapDrawable(bMapRotate);
image.setImageBitmap(bMapRotate);
image.setImageDrawable(bmd);

如果要从图库中裁剪图片，请使用以下代码片段：

    Intent viewMediaIntent = new Intent();
    viewMediaIntent.setAction(android.content.Intent.ACTION_VIEW);
    File file = new File("/image/*");    
    viewMediaIntent.setDataAndType(Uri.fromFile(file), "image/*");   
    viewMediaIntent.putExtra("crop","true");
    viewMediaIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_SINGLE_TOP);
    startActivityForResult(viewMediaIntent,1);

- Nikki

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错误/(5824)：无法打开'/image/*'，为什么？你有任何想法吗？ - DuyguK

我无法使用上述代码从图库打开图片。 它会显示多个裁剪选项。 - Abdul Wahab

Answer 2

尝试运行以下代码从画廊中裁剪所选图像。

 private static final String TEMP_PHOTO_FILE = "temporary_holder.jpg";  

 Intent photoPickerIntent = new Intent(Intent.ACTION_PICK, android.provider.MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
 photoPickerIntent.setType("image/*");
 photoPickerIntent.putExtra("crop", "true");
 photoPickerIntent.putExtra(MediaStore.EXTRA_OUTPUT, getTempUri());
 photoPickerIntent.putExtra("outputFormat", Bitmap.CompressFormat.JPEG.toString());
 startActivityForResult(photoPickerIntent, REQ_CODE_PICK_IMAGE);


private Uri getTempUri() {
return Uri.fromFile(getTempFile());
}

private File getTempFile() {
if (isSDCARDMounted()) {

File f = new File(Environment.getExternalStorageDirectory(),TEMP_PHOTO_FILE);
try {
f.createNewFile();
} catch (IOException e) {

}
return f;
} else {
return null;
}
}

private boolean isSDCARDMounted(){
String status = Environment.getExternalStorageState();
if (status.equals(Environment.MEDIA_MOUNTED))
return true;
return false;
}




 protected void onActivityResult(int requestCode, int resultCode,
    Intent imageReturnedIntent) {
super.onActivityResult(requestCode, resultCode, imageReturnedIntent);

switch (requestCode) {
case REQ_CODE_PICK_IMAGE:
    if (resultCode == RESULT_OK) {  
      if (imageReturnedIntent!=null){



           File tempFile = getTempFile();

          String filePath= Environment.getExternalStorageDirectory()
        + "/temporary_holder.jpg";
          System.out.println("path "+filePath);


Bitmap selectedImage =  BitmapFactory.decodeFile(filePath);
_image = (ImageView) findViewById(R.id.image);
_image.setImageBitmap(selectedImage );

 }
 }
 }

同时也可以查看这个教程1和这个教程2

- Hussain

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这段代码首先打开相册，我是通过教程2实现的， 我想打开特定的图像进行裁剪，而不是从相册中选择，图片是默认存在的...你能帮我吗？ - Abdul Wahab