在我的应用程序中，我使用 Tab。有三个选项卡。其中第三个选项卡是具有两个活动的活动组。在第一个活动中，用户有两个选项。用户可以从相机或图库中选择图像。选择图像后，用户应移至子活动，该活动将在该活动中显示所选图像。直到这个应用程序运行良好。但我面临的唯一问题是，当我从子活动移回父活动时，图像没有被清除。意味着一旦我从画廊/相机中选择图像，用户就会移动到子活动，并且图像正在显示在子活动中。现在，当我从子活动中按下后退按钮时，用户将返回到父活动，如果用户从厨房/相机中选择不同的图像，则该不同的图像在子活动中不存在。上一个图像在子活动中。
ABCGroup.java
public class ABCGroup extends ActivityGroup{
public static ABCGroup group;
private ArrayList<View> history;
View view;
int column_index;
@SuppressWarnings("deprecation")
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.history = new ArrayList<View>();
group = this;
view = getLocalActivityManager().startActivity("ParentActivity", new Intent(ABCGroup.this, Tab1.class).addFlags(Intent.FLAG_ACTIVITY_NO_HISTORY)).getDecorView();
replaceView(view);
}
public void replaceView(View v) {
history.add(v);
setContentView(v);
}
public void back() {
if(history.size() > 0)
{
history.remove(history.size()-1);
if(history.size()<=0)
{
finish();
}
else
{
setContentView(history.get(history.size()-1));
}
}
else
{
finish();
}
}
@Override
public void onBackPressed() {
ABCGroup.group.back();
}
@Override
public boolean onKeyDown(int keyCode, KeyEvent event){
if (keyCode == KeyEvent.KEYCODE_BACK){
ABCGroup.group.back();
return true;
}
return super.onKeyDown(keyCode, event);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
InputStream stream = null;
if (requestCode == Tab1.REQUEST_ID && resultCode == Activity.RESULT_OK) {
try
{
stream = getContentResolver().openInputStream(data.getData());
Bitmap original = null;
original= BitmapFactory.decodeStream(stream);
Uri selectedImageUri = data.getData();
String selectedImagePath = getPath(selectedImageUri);
}
catch (Exception e)
{
e.printStackTrace();
}
if (stream != null)
{
try
{
stream.close();
}
catch (Exception e)
{
e.printStackTrace();
}
}
}
if (requestCode == 3 && resultCode == Activity.RESULT_OK)
{
getContentResolver().notifyChange(Tab1.mUri, null);
ContentResolver cr = getContentResolver();
try
{
Tab1.mPhoto = android.provider.MediaStore.Images.Media.getBitmap(cr, Tab1.mUri);
Second.bmp = Tab1.mPhoto;
ByteArrayOutputStream bytes = new ByteArrayOutputStream();
Tab1.mPhoto.compress(Bitmap.CompressFormat.JPEG, 100, bytes);
File direct = new File(Environment.getExternalStorageDirectory() + "/ABCGroup");
String mydate = java.text.DateFormat.getDateTimeInstance().format(Calendar.getInstance().getTime());
Toast.makeText(getBaseContext(), "Time :" + mydate, 5000).show();
if(!direct.exists())
{
direct.mkdir();
File file = new File(Environment.getExternalStorageDirectory()+File.separator + "/ABCGroup/image" + mydate +".jpg");
file.createNewFile();
FileOutputStream fo = new FileOutputStream(file);
fo.write(bytes.toByteArray());
fo.close();
}
else
{
File file = new File(Environment.getExternalStorageDirectory()+File.separator + "/ABCGroup/image" + mydate +".jpg");
file.createNewFile();
FileOutputStream fo = new FileOutputStream(file);
fo.write(bytes.toByteArray());
fo.close();
}
View mview = ABCGroup.group.getLocalActivityManager().startActivity("activity3", new Intent(ABCGroup.this, Second.class).addFlags(Intent.FLAG_ACTIVITY_NO_HISTORY)).getDecorView();
replaceView(mview);
}
catch (Exception e)
{
Toast.makeText(this, e.getMessage(), Toast.LENGTH_SHORT).show();
}
}
}
public String getPath(Uri uri) {
String[] projection = { MediaStore.Images.Media.DATA };
Cursor cursor = managedQuery(uri, projection, null, null, null);
column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(getBaseContext());
SharedPreferences.Editor editor = preferences.edit();
editor.putString("data", cursor.getString(column_index) );
editor.commit();
View mview = ABCGroup.group.getLocalActivityManager().startActivity("activity3", new Intent(ABCGroup.this, Second.class).addFlags(Intent.FLAG_ACTIVITY_NO_HISTORY)).getDecorView();
replaceView(mview);
return cursor.getString(column_index);
}
public void onResume()
{
super.onResume();
column_index = 0;
}
}
Tab1.java
public class Tab1 extends ActivityGroup {
Button gallery, camera;
private ArrayList<View> myActivityHistory;
ImageView iv;
private static final int TAKE_PICTURE = 3;
public static final int REQUEST_ID = 1;
private static final int HALF = 2;
public static Uri mUri;
public static Bitmap mPhoto;
int i = 0;
@SuppressWarnings("deprecation")
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//setContentView(R.layout.tab1);
View viewToLoad = LayoutInflater.from(Tab1.this.getParent()).inflate(R.layout.tab1, null);
Tab1.this.setContentView(viewToLoad);
myActivityHistory = new ArrayList<View>();
gallery = (Button)viewToLoad.findViewById(R.id.gallery);
camera = (Button)viewToLoad.findViewById(R.id.camera);
iv = (ImageView)viewToLoad.findViewById(R.id.iv);
gallery.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v)
{
Intent intent = new Intent();
intent.setAction(Intent.ACTION_GET_CONTENT);
intent.addCategory(Intent.CATEGORY_OPENABLE);
intent.setType("image/*");
ABCGroup.group.startActivityForResult(intent, REQUEST_ID);
}
});
camera.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent i = new Intent("android.media.action.IMAGE_CAPTURE");
File f = new File(Environment.getExternalStorageDirectory(), "photo.jpg");
i.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(f));
mUri = Uri.fromFile(f);
ABCGroup.group.startActivityForResult(i, TAKE_PICTURE);
}
});
}
public void replaceContentView(String id, Intent newIntent)
{
View mview = ABCGroup.group.getLocalActivityManager().startActivity(id,newIntent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK)).getDecorView();
ABCGroup.group.replaceView(mview);
}
}
二.java
public class Second extends Activity {
public static Bitmap bmp;
Bitmap myBitmap;
String path;
ImageView iv;
int count = 0;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.second);
View viewToLoad = LayoutInflater.from(Second.this.getParent()).inflate(R.layout.second, null);
Second.this.setContentView(viewToLoad);
Button btn = (Button)viewToLoad.findViewById(R.id.button1);
iv = (ImageView)viewToLoad.findViewById(R.id.imageView1);
iv.setImageBitmap(bmp);
SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(getBaseContext());
path = preferences.getString("data", "");
File imgFile = new File(path);
if(imgFile.exists()){
Toast.makeText(getBaseContext(), "" + path, 1000).show();
myBitmap = BitmapFactory.decodeFile(imgFile.getAbsolutePath());
iv.setImageBitmap(myBitmap);
}
btn.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
ABCGroup.group.back();
}
});
}
@Override
public void onBackPressed() {
super.onBackPressed();
Intent intent = new Intent(Second.this, Tab1.class);
Tab1 parentActivity = (Tab1)getParent();
parentActivity.replaceContentView("Profile", new Intent(Second.this, Tab1.class).addFlags(Intent.FLAG_ACTIVITY_NO_HISTORY ) );
}
public void onResume()
{
super.onResume();
}
}