点击一个按钮，我想启动一个Intent来拍照，然后在我的布局中显示它。我使用以下代码：
private void takePicture() {
Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
File photo = new File(Environment.getExternalStorageDirectory(),
"Pic.jpg");
intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(photo));
imageUri = Uri.fromFile(photo);
startActivityForResult(intent, 0);
}
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
switch (requestCode) {
case 0:
if (resultCode == Activity.RESULT_OK) {
Uri selectedImage = imageUri;
getContentResolver().notifyChange(selectedImage, null);
ImageView imageView = (ImageView) findViewById(R.id.ImageView);
ContentResolver cr = getContentResolver();
Bitmap bitmap;
try {
bitmap = android.provider.MediaStore.Images.Media
.getBitmap(cr, selectedImage);
imageView.setImageBitmap(Bitmap.createScaledBitmap(bitmap, bitmap.getHeight()/2, bitmap.getWidth()/2, false));
Toast.makeText(this, selectedImage.toString(),
Toast.LENGTH_LONG).show();
} catch (Exception e) {
Toast.makeText(this, "Failed to load", Toast.LENGTH_SHORT)
.show();
}
}
图片肯定会显示，但是当我更改活动并返回到此图片时，图片就会消失。如何永久保存？
答案 0 :(得分：0)
答案 1 :(得分：0)
尝试此操作，因为我的代码工作正常
public class PhotoActivity extends Activity {
/** The Constant PICK_IMAGE. */
private static final int PICK_IMAGE = 0;
/** The Constant PICK_IMAGE_FROM_GALLERY. */
private static final int PICK_IMAGE_FROM_GALLERY = 1;
/** The btn cancel. */
private Button btnPhotoCamera,btnPhotoGallery,btnCancel;
/** The img view. */
private ImageView imgView;
/** The u. */
private Uri u;
/* (non-Javadoc)
* @see android.app.Activity#onCreate(android.os.Bundle)
*/
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_photo_options);
imgView=(ImageView)findViewById(R.id.imgDisplayImage);
btnPhotoCamera=(Button)findViewById(R.id.btnPhotoCamera);
btnPhotoGallery=(Button)findViewById(R.id.btnPhotoGallery);
btnCancel=(Button)findViewById(R.id.btnCancel);
btnPhotoCamera.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Intent camera=new Intent();
camera.setAction(MediaStore.ACTION_IMAGE_CAPTURE);
camera.putExtra("crop", "true");
File f=Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES);
u = Uri.fromFile(new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES),"myFile.jpg"));
camera.putExtra(MediaStore.EXTRA_OUTPUT, u);
startActivityForResult(camera, PICK_IMAGE);
}
});
btnPhotoGallery.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Intent intent = new Intent(Intent.ACTION_PICK);
intent.setType("image/*");
startActivityForResult(intent, PICK_IMAGE_FROM_GALLERY);
}
});
btnCancel.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Intent goStartUp=new Intent(PhotoActivity.this, StartUpActivity.class);
goStartUp.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(goStartUp);
finish();
}
});
}
/* (non-Javadoc)
* @see android.app.Activity#onActivityResult(int, int, android.content.Intent)
*/
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// TODO Auto-generated method stub
if (resultCode==RESULT_OK )
{
if(requestCode == PICK_IMAGE) {
InputStream is=null;
try {
is = this.getContentResolver().openInputStream(u);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
Bitmap bmp=BitmapFactory.decodeStream(is);
imgView.setImageBitmap(bmp);
Log.i("Inside", "PICK_IMAGE");
}
if (requestCode == PICK_IMAGE_FROM_GALLERY) {
Uri selectedImage = data.getData();
String[] filePathColumn = { MediaStore.Images.Media.DATA };
Log.d("data",filePathColumn[0]);
Cursor cursor = getContentResolver().query(selectedImage,filePathColumn, null, null, null);
cursor.moveToFirst();
int columnIndex = cursor.getColumnIndex(filePathColumn[0]);
String picturePath = cursor.getString(columnIndex);
cursor.close();
imgView.setImageBitmap(BitmapFactory.decodeFile(picturePath));
Log.i("Inside", "PICK_IMAGE_FROM_GALLERY");
}
}
}
}
XML文件：
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#f0f0f0" >
<TextView
android:id="@+id/lblSelectOptions"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="20dp"
android:layout_marginTop="20dp"
android:text="@string/two_options"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="#ff0000" />
<Button
android:id="@+id/btnPhotoCamera"
android:layout_width="75dp"
android:layout_height="wrap_content"
android:layout_below="@+id/lblSelectOptions"
android:layout_centerHorizontal="true"
android:layout_marginTop="10dp"
android:text="@string/camera" />
<Button
android:id="@+id/btnPhotoGallery"
android:layout_width="75dp"
android:layout_height="wrap_content"
android:layout_below="@+id/btnPhotoCamera"
android:layout_centerHorizontal="true"
android:layout_marginTop="10dp"
android:text="@string/gallery" />
<Button
android:id="@+id/btnCancel"
android:layout_width="120dp"
android:layout_height="wrap_content"
android:layout_below="@+id/btnPhotoGallery"
android:layout_centerHorizontal="true"
android:layout_marginTop="19dp"
android:text="@string/cancel" />
<TextView
android:id="@+id/lblDisplayImage"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/btnCancel"
android:layout_centerHorizontal="true"
android:layout_marginTop="10dp"
android:text="@string/below_this_text_image_will_be_displayed"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="#000000"
android:textSize="13dp" />
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_below="@+id/lblDisplayImage"
android:layout_centerInParent="true"
android:layout_marginTop="10dp"
android:gravity="bottom" >
<!--
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent" >
-->
<ImageView
android:id="@+id/imgDisplayImage"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="@+id/lblDisplayImage"
android:layout_centerInParent="true"
android:contentDescription="@string/area_where_image_is_to_be_displayed" />
<!-- </ScrollView> -->
</RelativeLayout>
</RelativeLayout>
还可以按照以下方式修改Android清单文件：
<manifest....
<uses-sdk
android:minSdkVersion="3"
android:targetSdkVersion="21" />
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.RECORD_VIDEO" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-feature
android:name="android.hardware.camera"
android:required="false" />
<application....
..........
</application>
</manifest>