从系统中取图片这个是写安卓非常常见的一个功能，但是很多时候我们每次我们都去写一个还是比较麻烦的。
下面我就介绍我写的一个已经封装好的一个类，先看截图
从截图上看，功能很清晰，点击获取图片按钮，出来一个半透明的界面，具有用相机拍照获取图片和从相册中选择两种途径去获取图片。
看完截图直接上代码
package com.yixuan;import java.io.File;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import com.example.handlertest.R;import android.app.Activity;import android.content.Context;import android.content.Intent;import android.graphics.Bitmap;import android.graphics.BitmapFactory;import android.net.Uri;import android.os.Bundle;import android.os.Environment;import android.provider.MediaStore;import android.util.DisplayMetrics;import android.view.View;import android.view.View.OnClickListener;import android.widget.Toast;/** * * <p> * 描 述：由于很多时候获取照片是从fragment中过来的，所以不好用activity的onResult * 方式解决，在一个静态类里面设置一个变量存放获取到的图片路径 * * <p> * 创 建 人：ztt * </p> * <p> * 创建时间：2015-2-4下午1:45:21 * </p> */public abstract class PickPhotoActivity extends Activity implementsOnClickListener {/* activity返回的回调类型 */public static final int PHOTO_PICKED_WITH_GALLERY = 9001;public static final int PHOTO_PICKED_WITH_CAMERA = 9002;public static final int CROPED_PHOTO = 9003;private final int cropWidth = 160;private final int cropHeight = 160;private Activity act;private boolean doCrop = true;protected int width;protected int height;protected int DEFAULT_WIDTH = 480;protected int DEFAULT_HEIGHT = 480;protected Context ctx;private int dpi;private int screenWidth;protected static String picPath;/* 取得的图片路径 */@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_pick_photo);ctx = this;Intent intent = getIntent();DisplayMetrics metric = new DisplayMetrics();getWindowManager().getDefaultDisplay().getMetrics(metric);float density = metric.density;dpi = (int) (metric.densityDpi * density);DEFAULT_WIDTH = metric.widthPixels;DEFAULT_HEIGHT = metric.heightPixels;// String path = intent.getStringExtra("tempPath");doCrop = intent.getBooleanExtra("doCrop", true);width = intent.getIntExtra("width", DEFAULT_WIDTH);height = intent.getIntExtra("height", DEFAULT_HEIGHT);File picturePathFile = new File(getPicPath());if (!picturePathFile.exists()) {picturePathFile.mkdirs();}screenWidth = metric.widthPixels;// DEFAULT_WIDTH = getScale() * 2;// DEFAULT_HEIGHT = getScale() * 2;System.out.println(getScale() * 2);initView();}private int getScale() {Double val = 4d * dpi / screenWidth;val = val * 100d;return val.intValue();}private void initView() {findViewById(R.id.pick_photo_from_camera).setOnClickListener(this);findViewById(R.id.pick_photo_from_gallery).setOnClickListener(this);findViewById(R.id.cancel).setOnClickListener(this);act = this;}@Overrideprotected void onActivityResult(int requestCode, int resultCode, Intent data) {super.onActivityResult(requestCode, resultCode, data);if (resultCode == RESULT_OK) {switch (requestCode) {case PHOTO_PICKED_WITH_CAMERA:if (doCrop) {doCropPhoto(new File(getFullPath()), cropWidth, cropHeight);} else {savePicture(picPath, null);}break;case PHOTO_PICKED_WITH_GALLERY:picPath = getPathFromURI(data.getData().toString());if (doCrop) {doCropPhoto(new File(picPath), cropWidth, cropHeight);} else {savePicture(picPath, null);}break;case CROPED_PHOTO:Bitmap img = data.getParcelableExtra("data");// ImageTools.savePhotoToSDCard(img, getPicPath(),// getTempImageName());savePicture(null, img);break;default:break;}} else {clearFullPath();}}public static void clearFullPath() {picPath = null;}public String getPicPath() {return Environment.getExternalStorageDirectory().toString() + "/";}private void savePicture(String picturePath, Bitmap bitmap) {Bitmap photo = null;try {if (bitmap == null) {photo = decodeBitmap(picturePath, width, height);} else {photo = bitmap;}savePictrue(photo);if (photo != null && !photo.isRecycled()) {photo.recycle();}picPath = getPicPath() + getTempImageName();afterSavePhoto(getFullPath());File file = new File(getFullPath());if (file.exists()) {file.delete();}}catch (Exception e) {e.printStackTrace();}}public static String getFullPath() {return picPath;}protected abstract void afterSavePhoto(String picPath);private void savePictrue(Bitmap newBitmap) {savePhotoToSDCard(newBitmap, getPicPath(), getTempImageName());}public static void savePhotoToSDCard(Bitmap photoBitmap, String path,String photoName) {if (checkSDCardAvailable()) {File dir = new File(path);if (!dir.exists()) {dir.mkdirs();}File photoFile = new File(path, photoName);FileOutputStream fileOutputStream = null;try {fileOutputStream = new FileOutputStream(photoFile);if (photoBitmap != null) {if (photoBitmap.compress(Bitmap.CompressFormat.PNG, 100,fileOutputStream)) {fileOutputStream.flush();}}} catch (FileNotFoundException e) {photoFile.delete();e.printStackTrace();} catch (IOException e) {photoFile.delete();e.printStackTrace();} finally {try {fileOutputStream.close();photoBitmap.recycle();} catch (IOException e) {e.printStackTrace();}}}}@Overridepublic void onClick(View v) {if (v.getId() == R.id.pick_photo_from_camera) {takePickture();} else if (v.getId() == R.id.pick_photo_from_gallery) {getPicktureFromGallery();} else {finish();}// switch(v.getId()){// case R.id.pick_photo_from_camera:// break;// }// switch (v.getId()) {// case R.id.pick_photo_from_camera:// takePickture();// break;// case R.id.pick_photo_from_gallery:// getPicktureFromGallery();// break;// case R.id.cancel:// finish();// break;// }}public static boolean checkSDCardAvailable() {return android.os.Environment.getExternalStorageState().equals(android.os.Environment.MEDIA_MOUNTED);}private void getPicktureFromGallery() {Intent openAlbumIntent = new Intent(Intent.ACTION_PICK);openAlbumIntent.setType("image/*");startActivityForResult(openAlbumIntent, PHOTO_PICKED_WITH_GALLERY);}private void takePickture() {Intent openCameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);picPath = getPicPath() + getTempImageName();Uri imageUri = Uri.fromFile(new File(picPath));openCameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);if (doCrop) {openCameraIntent.putExtra("return-data", true);}startActivityForResult(openCameraIntent, PHOTO_PICKED_WITH_CAMERA);}protected static String getTempImageName() {return "IMG_" + "TEMP" + ".png";// return FileUtil.getTempPath() + AppConstants.DEFAULT_PIC_NAME;}@SuppressWarnings("deprecation")public String getPathFromURI(String stringExtra) {Uri uri = Uri.parse(stringExtra);String[] proj = { MediaStore.Images.Media.DATA };android.database.Cursor actualimagecursor = PickPhotoActivity.this.managedQuery(uri, proj, null, null, null);int actual_image_column_index = actualimagecursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);actualimagecursor.moveToFirst();String img_path = actualimagecursor.getString(actual_image_column_index);return img_path;}public Bitmap decodeBitmap(String path, int width, int height) {BitmapFactory.Options options = new BitmapFactory.Options();options.inJustDecodeBounds = true;// 通过这个bitmap获取图片的宽和高 Bitmap bitmap = BitmapFactory.decodeFile(path, options);if (bitmap == null) {System.out.println("bitmap为空");}float realWidth = options.outWidth;float realHeight = options.outHeight;System.out.println("真实图片高度：" + realHeight + "宽度:" + realWidth);int scale = Math.max((int) (realWidth / width),(int) (realHeight / height));if (scale <= 1) {scale = 1;}options.inSampleSize = scale;options.inJustDecodeBounds = false;// 注意这次要把options.inJustDecodeBounds 设为 false,这次图片是要读取出来的。 // bitmap = BitmapFactory.decodeFile(path, options);int w = bitmap.getWidth();int h = bitmap.getHeight();System.out.println("缩略图高度：" + h + "宽度:" + w);return bitmap;}private void doCropPhoto(File f, int outWith, int outHeight) {try {// 启动gallery去剪辑这个照片final Intent intent = getCropImageIntent(Uri.fromFile(f), outWith,outHeight);if (act != null)act.startActivityForResult(intent, CROPED_PHOTO);elseact.startActivityForResult(intent, CROPED_PHOTO);} catch (Exception e) {Toast.makeText(act, act.getString(R.string.get_picture_failed),Toast.LENGTH_LONG).show();}}private Intent getCropImageIntent(Uri photoUri, int cropWidth,int cropHeight) {Intent intent = new Intent("com.android.camera.action.CROP").setDataAndType(photoUri, "image/*").putExtra("crop", "true").putExtra("return-data", true);intent.putExtra("aspectX", cropWidth);intent.putExtra("aspectY", cropHeight);intent.putExtra("outputX", cropWidth);intent.putExtra("outputY", cropHeight);return intent;}}
这个类很长，可能很多人不愿去看，如果觉得界面还凑合的就直接用吧，，下面我再如何使用
还有不愿面对失败的尴尬。曾经怀有远大理想，拥有完美的憧憬。
