调用Camera进行照相并将照片返回到App界面

讲到了

打开手机相机

照相对照片进行 大小处理 显示到自己的App上面

手机横竖屏时 保存View的当前状态

App按钮点击后触发打开Camera的事件

<ol><li><span style="font-family: Arial, Helvetica, sans-serif;"><span style="font-size:18px;">Intent takePictureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);</span></span></li></ol>然后，给intent添加数据，存储在ContentResolver中，方便显示在App中
<ol><li><span style="font-family: Arial, Helvetica, sans-serif;"><span style="font-size:18px;">takePictureIntent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(f));</span></span></li></ol>然后定义

<span style="font-size:18px;">startActivityForResult</span>

方法接收返回的数据。

在下面方法中，处理返回来的数据
<span style="font-size:18px;">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

case ACTION_TAKE_PHOTO_S: {
if (resultCode == RESULT_OK) {
handleSmallCameraPhoto(data);
}
break;
} // ACTION_TAKE_PHOTO_S

case ACTION_TAKE_VIDEO: {
if (resultCode == RESULT_OK) {
handleCameraVideo(data);
}
break;
} // ACTION_TAKE_VIDEO
} // switch
}</span>

下面方法是对图片进行处理，并显示到界面上。
<span style="font-size:18px;">private void setPic() {

int targetW = mImageView.getWidth();
int targetH = mImageView.getHeight();

BitmapFactory.Options bmOptions = new BitmapFactory.Options();
bmOptions.inJustDecodeBounds = true;
BitmapFactory.decodeFile(mCurrentPhotoPath, bmOptions);
int photoW = bmOptions.outWidth;
int photoH = bmOptions.outHeight;

int scaleFactor = 1;
if ((targetW > 0) || (targetH > 0)) {
scaleFactor = Math.min(photoW/targetW, photoH/targetH);
}

bmOptions.inJustDecodeBounds = false;
bmOptions.inSampleSize = scaleFactor;
bmOptions.inPurgeable = true;

Bitmap bitmap = BitmapFactory.decodeFile(mCurrentPhotoPath, bmOptions);

mImageView.setImageBitmap(bitmap);

mImageView.setVisibility(View.VISIBLE);

}</span>

下面这个方法当手机横竖屏时，保存手机当前状态的。

<span style="font-size:18px;">protected void onSaveInstanceState(Bundle outState) {
outState.putParcelable(BITMAP_STORAGE_KEY, mImageBitmap);
outState.putBoolean(IMAGEVIEW_VISIBILITY_STORAGE_KEY, (mImageBitmap != null) );
super.onSaveInstanceState(outState);
}</span>
和下面的方法是同步使用的
<span style="font-size:18px;">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
);
);
}</span>

下面方法加载完后，用于发送一个扫描指定图片的广播
p<span style="font-size:18px;">rivate 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);
}</span>

<span style="font-size:18px;">"android.intent.action.MEDIA_SCANNER_SCAN_FILE")</span><span style="font-size:24px;">该意图</span>

由于扫描工作是在MediaScanner服务中进行的，因此不会阻塞当前程序进程。当扫描大量媒体文件且实时性要求不高的情况下，适合使用该扫描方式。