Java tutorial
/* Copyright 2014 Giovanni Di Gregorio. Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. */ package org.wbt11a.nativecamera; //package com.wezka.nativecamera; import java.io.File; import java.io.FileNotFoundException; import java.io.IOException; import java.io.OutputStream; import java.io.ByteArrayOutputStream; import java.io.FileInputStream; import java.io.FileOutputStream; import java.util.Calendar; //import org.apache.cordova.ExifHelper; import org.apache.cordova.CallbackContext; import org.apache.cordova.CordovaInterface; import org.apache.cordova.CordovaPlugin; import org.apache.cordova.LOG; import org.apache.cordova.PluginResult; import org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; import android.app.Activity; import android.content.ContentValues; import android.content.Context; import android.content.Intent; import android.database.Cursor; import android.net.Uri; import android.os.Environment; import android.provider.MediaStore; import android.content.ActivityNotFoundException; import android.graphics.Bitmap; import android.graphics.Bitmap.CompressFormat; import android.graphics.BitmapFactory; import android.graphics.Matrix; import android.media.MediaScannerConnection; import android.media.MediaScannerConnection.MediaScannerConnectionClient; import android.os.Bundle; import android.util.Base64; import android.util.Log; /** * This class launches the camera view, allows the user to take a picture, * closes the camera view, and returns the captured image. When the camera view * is closed, the screen displayed before the camera view was shown is * redisplayed. */ public class NativeCameraLauncher extends CordovaPlugin { private static final String LOG_TAG = "NativeCameraLauncher"; private int mQuality; private int targetWidth; private int targetHeight; private Uri imageUri; private File photo; private static final String _DATA = "_data"; private CallbackContext callbackContext; private String date = null; public NativeCameraLauncher() { } void failPicture(String reason) { callbackContext.sendPluginResult(new PluginResult(PluginResult.Status.ERROR, reason)); } @Override public boolean execute(String action, JSONArray args, CallbackContext callbackContext) throws JSONException { PluginResult.Status status = PluginResult.Status.OK; String result = ""; this.callbackContext = callbackContext; try { if (action.equals("takePicture")) { this.targetHeight = 0; this.targetWidth = 0; this.mQuality = 80; this.targetHeight = args.getInt(4); this.targetWidth = args.getInt(3); this.mQuality = args.getInt(0); this.takePicture(); PluginResult r = new PluginResult(PluginResult.Status.NO_RESULT); r.setKeepCallback(true); callbackContext.sendPluginResult(r); return true; } return false; } catch (JSONException e) { e.printStackTrace(); callbackContext.sendPluginResult(new PluginResult(PluginResult.Status.JSON_EXCEPTION)); return true; } } public void takePicture() { // Save the number of images currently on disk for later Intent intent = new Intent(this.cordova.getActivity().getApplicationContext(), CameraActivity.class); this.photo = createCaptureFile(); this.imageUri = Uri.fromFile(photo); intent.putExtra(MediaStore.EXTRA_OUTPUT, this.imageUri); this.cordova.startActivityForResult((CordovaPlugin) this, intent, 1); } private File createCaptureFile() { File oldFile = new File(getTempDirectoryPath(this.cordova.getActivity().getApplicationContext()), "Pic-" + this.date + ".jpg"); if (oldFile.exists()) oldFile.delete(); Calendar c = Calendar.getInstance(); this.date = "" + c.get(Calendar.DAY_OF_MONTH) + c.get(Calendar.MONTH) + c.get(Calendar.YEAR) + c.get(Calendar.HOUR_OF_DAY) + c.get(Calendar.MINUTE) + c.get(Calendar.SECOND); File photo = new File(getTempDirectoryPath(this.cordova.getActivity().getApplicationContext()), "Pic-" + this.date + ".jpg"); return photo; } public void onActivityResult(int requestCode, int resultCode, Intent intent) { // If image available if (resultCode == Activity.RESULT_OK) { int rotate = 0; try { // Create an ExifHelper to save the exif data that is lost // during compression ExifHelper exif = new ExifHelper(); exif.createInFile(getTempDirectoryPath(this.cordova.getActivity().getApplicationContext()) + "/Pic-" + this.date + ".jpg"); exif.readExifData(); rotate = exif.getOrientation(); // Read in bitmap of captured image Bitmap bitmap; try { bitmap = android.provider.MediaStore.Images.Media .getBitmap(this.cordova.getActivity().getContentResolver(), imageUri); } catch (FileNotFoundException e) { Uri uri = intent.getData(); android.content.ContentResolver resolver = this.cordova.getActivity().getContentResolver(); bitmap = android.graphics.BitmapFactory.decodeStream(resolver.openInputStream(uri)); } // If bitmap cannot be decoded, this may return null if (bitmap == null) { this.failPicture("Error decoding image."); return; } bitmap = scaleBitmap(bitmap); // Add compressed version of captured image to returned media // store Uri bitmap = getRotatedBitmap(rotate, bitmap, exif); Log.i(LOG_TAG, "URI: " + this.imageUri.toString()); OutputStream os = this.cordova.getActivity().getContentResolver().openOutputStream(this.imageUri); bitmap.compress(Bitmap.CompressFormat.JPEG, this.mQuality, os); os.close(); // Restore exif data to file exif.createOutFile(this.imageUri.getPath()); exif.writeExifData(); // Send Uri back to JavaScript for viewing image this.callbackContext .sendPluginResult(new PluginResult(PluginResult.Status.OK, this.imageUri.toString())); bitmap.recycle(); bitmap = null; System.gc(); } catch (IOException e) { e.printStackTrace(); this.failPicture("Error capturing image."); } } // If cancelled else if (resultCode == Activity.RESULT_CANCELED) { this.failPicture("Camera cancelled."); } // If something else else { this.failPicture("Did not complete!"); } } public Bitmap scaleBitmap(Bitmap bitmap) { int newWidth = this.targetWidth; int newHeight = this.targetHeight; int origWidth = bitmap.getWidth(); int origHeight = bitmap.getHeight(); // If no new width or height were specified return the original bitmap if (newWidth <= 0 && newHeight <= 0) { return bitmap; } // Only the width was specified else if (newWidth > 0 && newHeight <= 0) { newHeight = (newWidth * origHeight) / origWidth; } // only the height was specified else if (newWidth <= 0 && newHeight > 0) { newWidth = (newHeight * origWidth) / origHeight; } // If the user specified both a positive width and height // (potentially different aspect ratio) then the width or height is // scaled so that the image fits while maintaining aspect ratio. // Alternatively, the specified width and height could have been // kept and Bitmap.SCALE_TO_FIT specified when scaling, but this // would result in whitespace in the new image. else { double newRatio = newWidth / (double) newHeight; double origRatio = origWidth / (double) origHeight; if (origRatio > newRatio) { newHeight = (newWidth * origHeight) / origWidth; } else if (origRatio < newRatio) { newWidth = (newHeight * origWidth) / origHeight; } } return Bitmap.createScaledBitmap(bitmap, newWidth, newHeight, true); } private Bitmap getRotatedBitmap(int rotate, Bitmap bitmap, ExifHelper exif) { Matrix matrix = new Matrix(); matrix.setRotate(rotate); try { bitmap = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true); exif.resetOrientation(); } catch (OutOfMemoryError oom) { // You can run out of memory if the image is very large: // http://simonmacdonald.blogspot.ca/2012/07/change-to-camera-code-in-phonegap-190.html // If this happens, simply do not rotate the image and return it unmodified. // If you do not catch the OutOfMemoryError, the Android app crashes. } return bitmap; } private String getTempDirectoryPath(Context ctx) { File cache = null; // SD Card Mounted if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) { cache = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + "/Android/data/" + ctx.getPackageName() + "/cache/"); } // Use internal storage else { cache = ctx.getCacheDir(); } // Create the cache directory if it doesn't exist if (!cache.exists()) { cache.mkdirs(); } return cache.getAbsolutePath(); } }