本文實例為大家分享了android自定義Camera拍照并查看圖片的具體代碼，供大家參考，具體內容如下
1、打開相機
a.預覽拍攝圖片，需用到SurfaceView，并且實現其回調函數implements SurfaceHolder.Callback；
activity_camera.xml
<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:orientation="vertical" > <SurfaceView android:id="@+id/sv" android:layout_width="match_parent" android:layout_height="0dp" android:layout_weight="1" /> <Button android:id="@+id/btn_camera" android:layout_width="match_parent" android:layout_height="wrap_content" android:text="拍照" /></LinearLayout>
2、獲取相機并開啟預覽
/** * 獲取系統相機 * * @return */ private Camera getcCamera() { Camera camera = null; try { camera = Camera.open(); } catch (Exception e) { camera = null; } return camera; }/** * 顯示相機預覽圖片 * * @return */ private void showCameraView(Camera camera,SurfaceHolder holder) { try { camera.setPreviewDisplay(holder); camera.setDisplayOrientation(90); camera.startPreview(); }catch (Exception e){ e.printStackTrace(); }; }/**** 實現界面回調處理*/ @Override public void surfaceCreated(SurfaceHolder holder) { showCameraView(mCamera, holder); } @Override public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) { mCamera.stopPreview(); showCameraView(mCamera, holder); } @Override public void surfaceDestroyed(SurfaceHolder holder) { clearCamera(); }}3、相機主頁面處理
public class CameraActivity extends AppCompatActivity implements SurfaceHolder.Callback{ private SurfaceView sv; private Camera mCamera; private SurfaceHolder holder; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_camera); sv = (SurfaceView)findViewById(R.id.sv); holder = sv.getHolder(); holder.addCallback(this); findViewById(R.id.btn_camera).setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { // 獲取當前相機參數 Camera.Parameters parameters = mCamera.getParameters(); // 設置相片格式 parameters.setPictureFormat(ImageFormat.JPEG); // 設置預覽大小 parameters.setPreviewSize(800, 480); // 設置對焦方式，這里設置自動對焦 parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_AUTO); mCamera.autoFocus(new Camera.AutoFocusCallback() { @Override public void onAutoFocus(boolean success, Camera camera) { // 判斷是否對焦成功 if (success) { // 拍照 第三個參數為拍照回調 mCamera.takePicture(null, null, new Camera.PictureCallback() { @Override public void onPictureTaken(byte[] data, Camera camera) { // data為完整數據 File file = new File("/sdcard/photo.png"); // 使用流進行讀寫 try { FileOutputStream fos = new FileOutputStream(file); try { fos.write(data); // 關閉流 fos.close(); // 查看圖片 Intent intent = new Intent(); // 傳遞路徑 intent.putExtra("path", file.getAbsolutePath()); setResult(0,intent); finish(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } catch (FileNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }); } } }); } }); } @Override protected void onResume() { super.onResume(); if (mCamera == null) { mCamera = getCamera(); if (holder != null) { showCameraView(mCamera, holder); } } } @Override protected void onPause() { // TODO Auto-generated method stub super.onPause(); // activity暫停時我們釋放相機內存 clearCamera(); } @Override protected void onDestroy() { super.onDestroy(); } /** * 釋放相機的內存 */ private void clearCamera() { // 釋放hold資源 if (mCamera != null) { // 停止預覽 mCamera.stopPreview(); mCamera.setPreviewCallback(null); // 釋放相機資源 mCamera.release(); mCamera = null; } }4、啟動activity（設置拍照完圖片路徑返回顯示圖片處理，一定要對圖片進行采樣率操作（很可能拍照的圖片太多而無法顯示，又不報任何異常））
public class MainActivity extends AppCompatActivity { private ImageView cameraIv; @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { if(resultCode == 0 && requestCode == 100) { String path = data.getStringExtra("path"); BitmapFactory.Options options = new BitmapFactory.Options(); options.inJustDecodeBounds = true; BitmapFactory.decodeFile(path, options); ImageSize imageSize = getImageViewSize(cameraIv); options.inSampleSize = caculateInSampleSize(options, imageSize.width, imageSize.height); // 使用獲得到的InSampleSize再次解析圖片 options.inJustDecodeBounds = false; Bitmap bitmap = BitmapFactory.decodeFile(path, options); cameraIv.setImageBitmap(bitmap); } super.onActivityResult(requestCode, resultCode, data); } @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); Button openButton = (Button) findViewById(R.id.button); cameraIv = (ImageView) findViewById(R.id.imageView); openButton.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { Intent intent = new Intent(MainActivity.this,CameraActivity.class); startActivityForResult(intent,100); } }); } /* 根據需求的寬和高以及圖片實際的寬和高計算SampleSize * * @param options * @param width * @param height * @return */ public static int caculateInSampleSize(BitmapFactory.Options options, int reqWidth, int reqHeight) { int width = options.outWidth; int height = options.outHeight; int inSampleSize = 1; if (width > reqWidth || height > reqHeight) { int widthRadio = Math.round(width * 1.0f / reqWidth); int heightRadio = Math.round(height * 1.0f / reqHeight); inSampleSize = Math.max(widthRadio, heightRadio); } return inSampleSize; } public static ImageSize getImageViewSize(ImageView imageView) { ImageSize imageSize = new ImageSize(); DisplayMetrics displayMetrics = imageView.getContext().getResources() .getDisplayMetrics(); LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams)imageView.getLayoutParams(); int width = imageView.getWidth();// 獲取imageview的實際寬度 if (width <= 0) { width = lp.width;// 獲取imageview在layout中聲明的寬度 } if (width <= 0) { width = displayMetrics.widthPixels; } int height = imageView.getHeight();// 獲取imageview的實際高度 if (height <= 0) { height = lp.height;// 獲取imageview在layout中聲明的寬度 } if (height <= 0) { height = displayMetrics.heightPixels; } imageSize.width = width; imageSize.height = height; return imageSize; } public static class ImageSize { int width; int height; }}以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持VEVB武林網。
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