相机 + 相册中获取相片并裁剪显示

一、代码

• xml布局中:两个按钮(分别从相机、相册获取照片)、一个显示图片的ImageView控件.

<Button
  android:id="@+id/bt_takePicture"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:layout_gravity="center_vertical"
  android:text="拍照" />
<Button
  android:id="@+id/bt_choosePicture"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:layout_gravity="center_vertical"
  android:text="相册" />

<ImageView
  android:id="@+id/iv_picture"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content" />

• 代码中

public class MainActivity extends Activity {
  public static final int TAKE_PICTURE = 1; // 拍照
  public static final int CROP_PICTURE = 2; // 裁剪
  private Uri imageUri; // 完整的file路径: ///图片地址

  private ImageView iv_picture;

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    iv_picture = (ImageView) findViewById(R.id.iv_picture);
    
    findViewById(R.id.bt_takePicture).setOnClickListener(new OnClickListener() {
      @Override
      public void onClick(View v) {
        // 创建File对象：照片的保存路径
        File outputImage = new File(Environment.getExternalStorageDirectory(), "temp.jpg");
        try {
          if (outputImage.exists()) {
            outputImage.delete();
          }
          outputImage.createNewFile();
        } catch (IOException e) {
          e.printStackTrace();
        }
        imageUri = Uri.fromFile(outputImage);
        Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
        intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
        startActivityForResult(intent, TAKE_PICTURE); // 启动裁剪
      }
    });
    
    
    findViewById(R.id.bt_choosePicture).setOnClickListener(new OnClickListener() {
      @Override
      public void onClick(View v) {
        // 创建File对象：照片的保存路径
        File outputImage = new File(Environment.getExternalStorageDirectory(), "outputImage.jpg");
        try {
          if (outputImage.exists()) {
            outputImage.delete();
          }
          outputImage.createNewFile();
        } catch (IOException e) {
          e.printStackTrace();
        }
        imageUri = Uri.fromFile(outputImage);
        Intent intent = new Intent(Intent.ACTION_PICK); // 拿到本地已存在资源
        intent.setType("image/*");
        intent.putExtra("crop", true);
        intent.putExtra("scale", true);
        intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
        startActivityForResult(intent, TAKE_PICTURE); // 启动裁剪
        
      }
    });
  }

  @Override
  protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    switch (requestCode) {
    case TAKE_PICTURE:
      if (resultCode == RESULT_OK) {
        if (data != null) {
           imageUri = data.getData();
        }
        Intent intent = new Intent("com.android.camera.action.CROP");
        intent.setDataAndType(imageUri, "image/*");
        intent.putExtra("scale", true);
        intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
        startActivityForResult(intent, CROP_PICTURE); // 启动裁剪程序
      }
      break;
    case CROP_PICTURE:
      if (resultCode == RESULT_OK) {
        try {
          Bitmap bitmap = BitmapFactory.decodeStream(getContentResolver().openInputStream(imageUri));
          
          /********************************
              图片可做压缩处理，防止OOM
          ********************************/
          iv_picture.setImageBitmap(bitmap); // 将裁剪后的照片显示出来
        } catch (FileNotFoundException e) {
          e.printStackTrace();
        }
      }
      break;
    }
  }
}

• 权限

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

---

二、分析

1.隐式启动系统相机 -> 返回照片至裁剪 -> 返回裁剪后的图片显示.
2.隐式启动系统相册 -> 返回照片至裁剪 -> 返回裁剪后的图片显示.
3.注意：显示图片前应该压缩，防止OOM.(本篇仅未做针对处理)

---

以上。如有错误和疑问，欢迎指正提出。 [e-mail]