如何從Android的Camera中捕獲圖像？

Question

我已經制作了一個應用程序，可以從相機捕獲照片。

我創建了兩個活動：在活動1中，有一個按鈕可以在單擊攝像機時啟動攝像機。 捕獲圖像后，圖像將傳遞到Activity2。

但是，當我運行該應用程序並啟動Activity1（使用一個按鈕），然后單擊該按鈕以啟動相機時，它會顯示一個彈出窗口，顯示消息“不幸的是，相機已停止”。 日志貓或控制台中沒有錯誤。

誰能幫我。 請。 非常感謝。

Answer 1

試試下面的代碼：

package com.example.sample1;


import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;



import android.os.Bundle;
import android.os.Environment;
import android.os.StatFs;
import android.provider.MediaStore;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;

public class CapturePhotoSample1 extends Activity implements OnClickListener
{


    public static final int TAKE_PHOTO=1; 
    ImageView imageView=null;

    private File folder;
    String imageFileName=null;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_capture_photo_sample1);

        Button button=(Button)this.findViewById(R.id.capture_button);
        button.setOnClickListener(this);
        button=null;

        imageView=(ImageView)this.findViewById(R.id.image_view1);

        folder = new File(getExternalFilesDir(Environment.DIRECTORY_PICTURES)+ "/sample1/");
        if (!folder.exists()) {
            folder.mkdir();
        }


    }

    private void dispatchTakePictureIntent(int actionCode) {
        Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        startActivityForResult(takePictureIntent,actionCode);

    }

    @Override
    public void onClick(View v) {
        // TODO Auto-generated method stub

        int id=v.getId();

        if(id==R.id.capture_button)
            this.dispatchTakePictureIntent(TAKE_PHOTO);
    }

    @Override

    public boolean onCreateOptionsMenu(Menu menu) {

        MenuInflater inflater = getMenuInflater();

        inflater.inflate(R.menu.menu1, menu);

        return true;

    }

    public void handleCameraPhoto(Intent intent)
    {
        Bundle extras=intent.getExtras();
        Bitmap bitmap=(Bitmap)extras.get("data");
        this.imageView.setImageBitmap(bitmap);

        if(this.isExternalStorageAvailable())
        {
            this.imageFileName="img_"+SDUtil.now(-1)+".png"; 

                    /*SDUtil.now() is our own library.It is for creating file name with respect to data and time.IF u copy the hole program means sdutil shows error.For that you write a logic for creating a file name. */

            String path=folder+"/"+this.imageFileName;

            FileOutputStream fos=null;
            BufferedOutputStream bos=null;

            try
            {
                fos=new FileOutputStream(path);
                bos=new BufferedOutputStream(fos);
                bitmap.compress(Bitmap.CompressFormat.PNG, 40, bos);
            }
            catch(Exception ex)
            {
                ex.printStackTrace();
            }

            if(bos!=null)
            {
                try
                {
                    bos.flush();
                    //bos.close();
                }
                catch(Exception ex)
                {
                    ex.printStackTrace();
                }
            }

            if(bos!=null)
            {
                try
                {
                    bos.close();
                }
                catch(Exception ex)
                {
                    ex.printStackTrace();
                }
            }


            if(fos!=null)
            {
                try
                {
                    fos.close();
                }
                catch(Exception ex)
                {
                    ex.printStackTrace();
                }

            }

            bos=null;
            fos=null;

        }
    }

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

        if(resultCode==Activity.RESULT_OK)
        {
            if(requestCode==TAKE_PHOTO)
            {
                handleCameraPhoto(data);
            }
        }


    }

    private boolean isExternalStorageAvailable() {

        StatFs stat = new StatFs(Environment.getExternalStorageDirectory()
                .getPath());
        double sdAvailSize = (double) stat.getAvailableBlocks()
                * (double) stat.getBlockSize();
        // One binary gigabyte equals 1,073,741,824 bytes.
        double mbAvailable = sdAvailSize / 1048576;

        String state = Environment.getExternalStorageState();
        boolean mExternalStorageAvailable = false;
        boolean mExternalStorageWriteable = false;

        if (Environment.MEDIA_MOUNTED.equals(state)) {
            // We can read and write the media
            mExternalStorageAvailable = mExternalStorageWriteable = true;
        } else if (Environment.MEDIA_MOUNTED_READ_ONLY.equals(state)) {
            // We can only read the media
            mExternalStorageAvailable = true;
            mExternalStorageWriteable = false;
        } else {
            // Something else is wrong. It may be one of many other states, but
            // all we need
            // to know is we can neither read nor write
            mExternalStorageAvailable = mExternalStorageWriteable = false;
        }

        if (mExternalStorageAvailable == true
                && mExternalStorageWriteable == true && mbAvailable > 10) {
            return true;
        } else {
            return false;
        }
    }

}

Answer 2

看一下我在這個主題上寫的這篇博客文章：

將相機活動用於縮略圖和全尺寸圖像

它可以幫助您找出問題所在。

這些步驟是：

1.因此，首先像以前一樣，我們需要創建一個靜態int

public static final int CAPTURE_IMAGE_FULLSIZE_ACTIVITY_REQUEST_CODE = 1777; 

2.接下來，我們激發意圖啟動Activity以獲得結果：

Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
File file = new File(Environment.getExternalStorageDirectory()+File.separator + "image.jpg");
intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(file));
startActivityForResult(intent, CAPTURE_IMAGE_FULLSIZE_ACTIVITY_REQUEST_CODE);

在這里，我們實際上是將URI作為一個額外的傳遞給該意圖，以便在拍攝圖像時將其保存在該位置。

3.最后，我們將在onActivityResult收到結果：

protected void onActivityResult(int requestCode, int resultCode, Intent data) 
{  
    //Check that request code matches ours:
    if (requestCode == CAPTURE_IMAGE_FULLSIZE_ACTIVITY_REQUEST_CODE) 
    {
        //Get our saved file into a bitmap object:
       File file = new File(Environment.getExternalStorageDirectory()+File.separator + "image.jpg");
       Bitmap bitmap = decodeSampledBitmapFromFile(file.getAbsolutePath(), 1000, 700);
    }
}

當decodeSampledBitmapFromFile方法為：

public static Bitmap decodeSampledBitmapFromFile(String path, int reqWidth, int reqHeight) 
{ // BEST QUALITY MATCH

    //First decode with inJustDecodeBounds=true to check dimensions
    final BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeFile(path, options);

    // Calculate inSampleSize, Raw height and width of image
    final int height = options.outHeight;
    final int width = options.outWidth;
    options.inPreferredConfig = Bitmap.Config.RGB_565;
    int inSampleSize = 1;

    if (height > reqHeight) 
    {
        inSampleSize = Math.round((float)height / (float)reqHeight);
    }
    int expectedWidth = width / inSampleSize;

    if (expectedWidth > reqWidth) 
    {
        //if(Math.round((float)width / (float)reqWidth) > inSampleSize) // If bigger SampSize..
        inSampleSize = Math.round((float)width / (float)reqWidth);
    }

    options.inSampleSize = inSampleSize;

    // Decode bitmap with inSampleSize set
    options.inJustDecodeBounds = false;

    return BitmapFactory.decodeFile(path, options);
}

不要忘記將relevent攝像機權限添加到清單文件中：

<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" />
<uses-feature android:name="android.hardware.camera.autofocus" />

Answer 3

確保添加權限

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

如果那不能解決您的問題，那么您應該向我們顯示您的代碼

Answer 4

如果使用startActiviyForResult（），則僅需要一個Activity：

Bello，一個用於從相機應用程序拍照的簡單源代碼，您需要使用startActiviyForResult（）啟動Activity並從相機應用程序接收意圖。

Java源代碼：

package com.example.coursandroid_chp;

    import android.os.Bundle;
    import android.provider.MediaStore;
    import android.app.Activity;
    import android.content.Intent;
    import android.graphics.Bitmap;
    import android.util.Log;
    import android.view.Menu;
    import android.view.View;
    import android.view.View.OnClickListener;
    import android.widget.Button;
    import android.widget.ImageView;

    public class MediaActivity extends Activity {

        private static final String TAG = "MediaActivity";
        private static final int REQUEST_IMAGE_CAPTURE = 1;
        private static final int REQUEST_VIDEO_CAPTURE = 2;
        private Button mCameraPhotoButton;
        private Button mCameraVideoButton;
        private ImageView mPhotoImageView;

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.screen_media);
            mCameraPhotoButton = (Button) this.findViewById(R.id.screen_media_camera_photo_button);
            mCameraVideoButton = (Button) this.findViewById(R.id.screen_media_camera_video_button);
            mPhotoImageView = (ImageView) this.findViewById(R.id.screen_media_photo_imageview);
            mCameraPhotoButton.setOnClickListener(onClickListener);
            mCameraVideoButton.setOnClickListener(onClickListener);

        }

        @Override
        public boolean onCreateOptionsMenu(Menu menu) {
            // Inflate the menu; this adds items to the action bar if it is present.
            getMenuInflater().inflate(R.menu.screen_media, menu);
            return true;
        }

        private OnClickListener onClickListener = new OnClickListener() {

            @Override
            public void onClick(View v) {
                switch (v.getId()) {
                case R.id.screen_media_camera_photo_button:
                    startActivityForResult(new Intent(MediaStore.ACTION_IMAGE_CAPTURE), REQUEST_IMAGE_CAPTURE);
                    break;
                case R.id.screen_media_camera_video_button:
                    startActivityForResult(new Intent(MediaStore.ACTION_VIDEO_CAPTURE), REQUEST_VIDEO_CAPTURE);
                    break;
                }
            }
        };

        @Override
        protected void onActivityResult(int requestCode, int resultCode, Intent data) {

            if (requestCode == REQUEST_IMAGE_CAPTURE) {

                switch (resultCode) {
                case RESULT_OK:
                    Log.v(TAG, "Picture taken! :)");
                    if (data != null) {
                        Bitmap bitmap = data.getParcelableExtra("data");
                        mPhotoImageView.setImageBitmap(bitmap);
                    }
                    break;
                case RESULT_CANCELED:
                    Log.v(TAG, "Picture canceled! :(");
                    break;
                }
            } else if (requestCode == REQUEST_VIDEO_CAPTURE) {

                switch (resultCode) {
                case RESULT_OK:
                    Log.v(TAG, "Video taken! :)");
                    break;
                case RESULT_CANCELED:
                    Log.v(TAG, "Video canceled! :(");
                    break;
                }
            }

        }

    }



Xml layout file


 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
            xmlns:tools="http://schemas.android.com/tools"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            tools:context=".MediaActivity" >

            <Button
                android:id="@+id/screen_media_camera_photo_button"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentTop="true"
                android:layout_centerHorizontal="true"
                android:layout_marginTop="32dp"
                android:text="Camera photo" />

            <Button
                android:id="@+id/screen_media_camera_video_button"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_below="@+id/screen_media_camera_photo_button"
                android:layout_centerHorizontal="true"
                android:layout_marginTop="28dp"
                android:text="Camera video" />

            <ImageView
                android:id="@+id/screen_media_photo_imageview"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:layout_below="@+id/screen_media_camera_video_button"
                android:layout_centerHorizontal="true"
                android:layout_marginLeft="32dp"
                android:layout_marginTop="57dp"
                android:src="@drawable/ic_bitmap" />

        </RelativeLayout>

Answer 5

檢查活動中的以下代碼

    protected void onActivityResult(int requestCode, int resultCode, Intent data)
{ 
    //Check that request code matches ours:
    if (requestCode == CAPTURE_IMAGE_THUMBNAIL_ACTIVITY_REQUEST_CODE)
    { //Check if your application folder exists in the external storage, if not create it:
        your code should be here..... 
        //Check if data in not null and extract the Bitmap:
        if (data != null)
        {
            String filename = "image";
            String fileNameExtension = ".jpg";
            File sdCard = Environment.getExternalStorageDirectory();
            String imageStorageFolder = File.separator+"Your application Folder"+File.separator;
            File destinationFile = new File(sdCard, imageStorageFolder + filename + fileNameExtension);
            Log.d(TAG, "the destination for image file is: " + destinationFile );
            if (data.getExtras() != null)
            {
                Bitmap bitmap = (Bitmap)data.getExtras().get("data");
                try
                {
                    FileOutputStream out = new FileOutputStream(destinationFile);
                    bitmap.compress(Bitmap.CompressFormat.PNG, 100, out);
                    out.flush();
                    out.close();
                }
                catch (Exception e)
                {
                    Log.e(TAG, "ERROR:" + e.toString());
                }
            }}}