我的代码如下，单击即可打开相机，拍照，从相机获取照片，然后放入图像视图中。不过，我想拍摄图像并在图像上应用文本（某种时间戳，最好是图像的时间戳，或者只是系统日期时间）并保存为 jpeg。
如果有人能帮助我那就太好了。
public class PhotoIntentActivity extends Activity {
private static final int ACTION_TAKE_PHOTO_B = 1;
private static final String BITMAP_STORAGE_KEY = "viewbitmap";
private static final String IMAGEVIEW_VISIBILITY_STORAGE_KEY = "imageviewvisibility";
private ImageView mImageView;
private Bitmap mImageBitmap;
private String mCurrentPhotoPath;
private static final String JPEG_FILE_PREFIX = "IMG_";
private static final String JPEG_FILE_SUFFIX = ".jpg";
private AlbumStorageDirFactory mAlbumStorageDirFactory = null;
/* Photo album for this application */
private String getAlbumName() {
return getString(R.string.album_name);
}
private File getAlbumDir() {
File storageDir = null;
if (Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState())) {
storageDir = mAlbumStorageDirFactory.getAlbumStorageDir(getAlbumName());
if (storageDir != null) {
if (! storageDir.mkdirs()) {
if (! storageDir.exists()){
Log.d("CameraSample", "failed to create directory");
return null;
}
}
}
} else {
Log.v(getString(R.string.app_name), "External storage is not mounted READ/WRITE.");
}
return storageDir;
}
private File createImageFile() throws IOException {
// Create an image file name
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
String imageFileName = JPEG_FILE_PREFIX + timeStamp + "_";
File albumF = getAlbumDir();
File imageF = File.createTempFile(imageFileName, JPEG_FILE_SUFFIX, albumF);
return imageF;
}
private File setUpPhotoFile() throws IOException {
File f = createImageFile();
mCurrentPhotoPath = f.getAbsolutePath();
return f;
}
private void setPic() {
/* There isn't enough memory to open up more than a couple camera photos */
/* So pre-scale the target bitmap into which the file is decoded */
/* Get the size of the ImageView */
int targetW = mImageView.getWidth();
int targetH = mImageView.getHeight();
/* Get the size of the image */
BitmapFactory.Options bmOptions = new BitmapFactory.Options();
bmOptions.inJustDecodeBounds = true;
BitmapFactory.decodeFile(mCurrentPhotoPath, bmOptions);
int photoW = bmOptions.outWidth;
int photoH = bmOptions.outHeight;
/* Figure out which way needs to be reduced less */
int scaleFactor = 1;
if ((targetW > 0) || (targetH > 0)) {
scaleFactor = Math.min(photoW/targetW, photoH/targetH);
}
/* Set bitmap options to scale the image decode target */
bmOptions.inJustDecodeBounds = false;
bmOptions.inSampleSize = scaleFactor;
bmOptions.inPurgeable = true;
/* NEWELY ADDED CODE */
/* Decode the JPEG file into a Bitmap */
Bitmap bitmap = BitmapFactory.decodeFile(mCurrentPhotoPath, bmOptions);
Bitmap replacedBitmap = timestampItAndSave(bitmap);
/* Associate the Bitmap to the ImageView */
mImageView.setImageBitmap(replacedBitmap);
mImageView.setVisibility(View.VISIBLE);
/* NEWELY ADDED CODE */
}
private void galleryAddPic() {
Intent mediaScanIntent = new Intent("android.intent.action.MEDIA_SCANNER_SCAN_FILE");
File f = new File(mCurrentPhotoPath);
Uri contentUri = Uri.fromFile(f);
mediaScanIntent.setData(contentUri);
this.sendBroadcast(mediaScanIntent);
}
private void dispatchTakePictureIntent(int actionCode) {
Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
switch(actionCode) {
case ACTION_TAKE_PHOTO_B:
File f = null;
try {
f = setUpPhotoFile();
mCurrentPhotoPath = f.getAbsolutePath();
takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(f));
} catch (IOException e) {
e.printStackTrace();
f = null;
mCurrentPhotoPath = null;
}
break;
default:
break;
} // switch
startActivityForResult(takePictureIntent, actionCode);
}
private void handleBigCameraPhoto() {
if (mCurrentPhotoPath != null) {
setPic();
galleryAddPic();
mCurrentPhotoPath = null;
}
}
Button.OnClickListener mTakePicOnClickListener =
new Button.OnClickListener() {
public void onClick(View v) {
dispatchTakePictureIntent(ACTION_TAKE_PHOTO_B);
}
};
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mImageView = (ImageView) findViewById(R.id.imageView1);
mImageBitmap = null;
Button picBtn = (Button) findViewById(R.id.btnIntend);
setBtnListenerOrDisable(
picBtn,
mTakePicOnClickListener,
MediaStore.ACTION_IMAGE_CAPTURE
);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.FROYO) {
mAlbumStorageDirFactory = new FroyoAlbumDirFactory();
} else {
mAlbumStorageDirFactory = new BaseAlbumDirFactory();
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode) {
case ACTION_TAKE_PHOTO_B: {
if (resultCode == RESULT_OK) {
handleBigCameraPhoto();
}
break;
} // ACTION_TAKE_PHOTO_B
}
}
// Some lifecycle callbacks so that the image can survive orientation change
@Override
protected void onSaveInstanceState(Bundle outState) {
outState.putParcelable(BITMAP_STORAGE_KEY, mImageBitmap);
outState.putBoolean(IMAGEVIEW_VISIBILITY_STORAGE_KEY, (mImageBitmap != null) );
super.onSaveInstanceState(outState);
}
@Override
protected void onRestoreInstanceState(Bundle savedInstanceState) {
super.onRestoreInstanceState(savedInstanceState);
mImageBitmap = savedInstanceState.getParcelable(BITMAP_STORAGE_KEY);
mImageView.setImageBitmap(mImageBitmap);
mImageView.setVisibility(
savedInstanceState.getBoolean(IMAGEVIEW_VISIBILITY_STORAGE_KEY) ?
ImageView.VISIBLE : ImageView.INVISIBLE
);
}
/**
* Indicates whether the specified action can be used as an intent. This
* method queries the package manager for installed packages that can
* respond to an intent with the specified action. If no suitable package is
* found, this method returns false.
* http://android-developers.blogspot.com/2009/01/can-i-use-this-intent.html
*
* @param context The application's environment.
* @param action The Intent action to check for availability.
*
* @return True if an Intent with the specified action can be sent and
* responded to, false otherwise.
*/
public static boolean isIntentAvailable(Context context, String action) {
final PackageManager packageManager = context.getPackageManager();
final Intent intent = new Intent(action);
List<ResolveInfo> list =
packageManager.queryIntentActivities(intent,
PackageManager.MATCH_DEFAULT_ONLY);
return list.size() > 0;
}
private void setBtnListenerOrDisable(
Button btn,
Button.OnClickListener onClickListener,
String intentName
) {
if (isIntentAvailable(this, intentName)) {
btn.setOnClickListener(onClickListener);
} else {
btn.setText(
getText(R.string.cannot).toString() + " " + btn.getText());
btn.setClickable(false);
}
}
}
在 4.0 模拟器上出现错误。日志猫。
07-12 20:53:50.510: D/gralloc_goldfish(545): Emulator without GPU emulation detected.
07-12 20:53:54.861: W/IInputConnectionWrapper(545): showStatusIcon on inactive InputConnection
07-12 20:54:00.700: D/dalvikvm(545): GC_FOR_ALLOC freed 114K, 3% free 10052K/10311K, paused 217ms
07-12 20:54:00.710: I/dalvikvm-heap(545): Grow heap (frag case) to 11.072MB for 1228816-byte allocation
07-12 20:54:00.860: D/dalvikvm(545): GC_CONCURRENT freed 3K, 3% free 11249K/11527K, paused 4ms+3ms
07-12 20:54:00.960: D/AndroidRuntime(545): Shutting down VM
07-12 20:54:00.960: W/dalvikvm(545): threadid=1: thread exiting with uncaught exception (group=0x409961f8)
07-12 20:54:01.000: E/AndroidRuntime(545): FATAL EXCEPTION: main
07-12 20:54:01.000: E/AndroidRuntime(545): java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=1, result=-1, data=null} to activity {com.example.android.photobyintent/com.example.android.photobyintent.PhotoIntentActivity}: java.lang.IllegalStateException: Immutable bitmap passed to Canvas constructor
07-12 20:54:01.000: E/AndroidRuntime(545): at android.app.ActivityThread.deliverResults(ActivityThread.java:2976)
07-12 20:54:01.000: E/AndroidRuntime(545): at android.app.ActivityThread.handleSendResult(ActivityThread.java:3019)
07-12 20:54:01.000: E/AndroidRuntime(545): at android.app.ActivityThread.access$1100(ActivityThread.java:122)
07-12 20:54:01.000: E/AndroidRuntime(545): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1176)
07-12 20:54:01.000: E/AndroidRuntime(545): at android.os.Handler.dispatchMessage(Handler.java:99)
07-12 20:54:01.000: E/AndroidRuntime(545): at android.os.Looper.loop(Looper.java:137)
07-12 20:54:01.000: E/AndroidRuntime(545): at android.app.ActivityThread.main(ActivityThread.java:4340)
07-12 20:54:01.000: E/AndroidRuntime(545): at java.lang.reflect.Method.invokeNative(Native Method)
07-12 20:54:01.000: E/AndroidRuntime(545): at java.lang.reflect.Method.invoke(Method.java:511)
07-12 20:54:01.000: E/AndroidRuntime(545): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
07-12 20:54:01.000: E/AndroidRuntime(545): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
07-12 20:54:01.000: E/AndroidRuntime(545): at dalvik.system.NativeStart.main(Native Method)
07-12 20:54:01.000: E/AndroidRuntime(545): Caused by: java.lang.IllegalStateException: Immutable bitmap passed to Canvas constructor
07-12 20:54:01.000: E/AndroidRuntime(545): at android.graphics.Canvas.<init> (Canvas.java:133)
07-12 20:54:01.000: E/AndroidRuntime(545): at com.example.android.photobyintent.PhotoIntentActivity.timestampItAndSave(PhotoIntentActivity.java:103)
07-12 20:54:01.000: E/AndroidRuntime(545): at com.example.android.photobyinten
t.PhotoIntentActivity.setPic(PhotoIntentActivity.java:154)
07-12 20:54:01.000: E/AndroidRuntime(545): 在 com.example.android.photobyintent.PhotoIntentActivity.handleBigCameraPhoto(PhotoIntentActivity.java:199)
07-12 20:54:01.000: E/AndroidRuntime(545): 在 com.example.android.photobyintent.PhotoIntentActivity.onActivityResult(PhotoIntentActivity.java:244)
07-12 20:54:01.000: E/AndroidRuntime(545): 在 android.app.Activity.dispatchActivityResult(Activity.java:4649)
07-12 20:54:01.000: E/AndroidRuntime(545): 在 android.app.ActivityThread.deliverResults(ActivityThread.java:2972)
07-12 20:54:01.000: E/AndroidRuntime(545): ... 11 更多
使用绘制位图更新了代码。
private Bitmap timestampItAndSave(Bitmap toEdit){
Bitmap dest = Bitmap.createBitmap(toEdit.getWidth(), toEdit.getHeight(), Bitmap.Config.ARGB_8888);
SimpleDateFormat sdf = new SimpleDateFormat("YYYY-MM-DD HH:MM:SS");
String dateTime = sdf.format(Calendar.getInstance().getTime()); // reading local time in the system
Canvas cs = new Canvas(dest);
Paint tPaint = new Paint();
tPaint.setTextSize(35);
tPaint.setColor(Color.BLUE);
tPaint.setStyle(Style.FILL);
float height = tPaint.measureText("yY");
cs.drawText(dateTime, 20f, height+15f, tPaint);
cs.drawBitmap(dest,0 ,0,tPaint);
try {
dest.compress(Bitmap.CompressFormat.JPEG, 100, new FileOutputStream(new File(Environment.getExternalStorageDirectory() + "/timestamped")));
} catch (FileNotFoundException e) {
e.printStackTrace();
return null;
}
return dest;
}
