I've got problem with my grid view. I would like to store images in table and then display them in grid view.
// ImageAdapter
String[] strings = db.getPictures();
Integer[] ints = new Integer[strings.length];
for (int i=0; i < strings.length; i++) {
ints[i] = Integer.parseInt(strings[i]);
}
imageView.setImageResource(ints[position]);
return imageView;
//DatabaseHandler
public String[] getPictures(){
int i=0;
String selectQuery = "SELECT pictureName FROM Category";
SQLiteDatabase db = this.getReadableDatabase();
Cursor c = db.rawQuery(selectQuery, null);
int rowsNumber=c.getCount();
String[] mThumbIds;
mThumbIds= new String[rowsNumber];
if (c.moveToFirst()) {
do {
mThumbIds[i]=c.getString(0);
i++;
} while (c.moveToNext());
}
return mThumbIds;
}
And when i run my app it crush at starting. Single string I save like R.drawable.ic_work
In most scenarios, your device wont be able to load a single original image into memory leave alone a list. You need to scale your image before you display it.
As you said you are saving R.drawable.ic_work as string.
The problem is you are using imageView.setImageResource(ints[position]); while R.drawable.ic_work is String.
Solution is instead of storing R.drawable.ic_work as String store it as int because your R.drawable.ic_work represents with an int ID.
Related
hi
why load text from String array and set text to textview is very slow in big string array?
please help to me.
//get khotbe text from database and copy to khotbe activity
private void setkhotbetextarabicfarsi() {
this.sqliteDB = SQLiteDatabase.openOrCreateDatabase(this.getDatabasePath("aliname").getPath(), (SQLiteDatabase.CursorFactory) null);
Itemid = this.getIntent().getIntExtra("selectedFromListid", 1);
Cursor cursorLines = this.sqliteDB.rawQuery("SELECT * FROM khotbe where IDFehrest=" + this.Itemid , (String[]) null);
allrecs = cursorLines.getCount();
matn = new String[allrecs];
if (this.allrecs != 0) {
cursorLines.moveToFirst();
for (int i = 0; i < this.allrecs; ++i) {
String TextArabicOfKhotbe = cursorLines.getString(cursorLines.getColumnIndex("TextArabicOfKhotbe"));
int IDkhotbe = cursorLines.getInt(cursorLines.getColumnIndex("IDkhotbe"));
this.matn[i] = TextArabicOfKhotbe;
cursorLines.moveToNext();
}
}
and main code:
for(int var1 = 0; var1 < this.allrecs; ++var1) {
tvArabic = new JustifiedTextView(this);
tvArabic.setText(matn[var1]);
you are creating the textviews in loop that might making it slow.. try populating the array values using an adapter..
Also check the number of rows you are accessing from the DB. if they are huge in number, they would require more time to be fetched.
Use limit in that case.
I need to create a drop down list (spinner) in eclipse for Android whereby the drop down options can be created by the user.
To do this I've created a SQLiteDatabase, which I want to convert into a string array to be put into an array adapter, which can then be fed into the spinner.
Database details are:
DATABASE_NAME = "carddb"
DATABASE_TABLE = "cardtable"
Then the column I wish to read the values from is:
KEY_CARDDETAILS = "_carddetails";
Here is my code so far, adapted from another question on this site (Link: how to get the database value to a String array in android(sqlite Database))
myDB = cardtable.this.openOrCreateDatabase("carddb", MODE_PRIVATE, null);
Cursor cardcursor = cardDB.rawQuery("SELECT * FROM cardtable");
String[] cardstringarray = new String[cardcursor.getCount()];
cardcursor.moveToFirst();
int counter = 0;
while(cardcursor.moveToNext()){
String carddetailss = cardcursor.getString(cardcursor.getColumnIndex("NAME"));
cardstringarray[counter] = carddetailss;
counter++;
}
I'm getting an error under "myDB" and "cardtable", both errors saying they cannot be resolved into a variable!
PLEASE HELP!
Use this code
String[] displayName={};
ArrayList<String> List=new ArrayList<String>();
myDB = cardtable.this.openOrCreateDatabase("carddb", MODE_PRIVATE, null); Cursor cardcursor = cardDB.rawQuery("SELECT * FROM cardtable");
String[] cardstringarray = new String[cardcursor.getCount()];
cardcursor.moveToFirst();
int counter = 0;
while(cardcursor.moveToNext()){
String carddetailss = cardcursor.getString(cardcursor.getColumnIndex("NAME"));
List.add(carddetailss);
counter++;
}
if(List != null){
listEmail=(ListView)findViewById(R.id.listEmail);
listEmail.setVisibility(view.VISIBLE);
displayName=(String[])List.toArray(new String[0]);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, android.R.id.text1, displayName);
// Assign adapter to ListView
listEmail.setAdapter(adapter);
}
This is work for you. Use spinner instead of listView.
I have a List View that Displays songs in alphebetical order being populated by this method
public void updatelist(){
Cursor cursor = getContentResolver().query(MediaStore.Audio.Media.EXTERNAL_CONTENT_URI, null, null, null,null);
int j =0;
if(cursor.moveToFirst()){
do{
int ALBUM_ID = cursor.getInt((cursor.getColumnIndex(MediaStore.Audio.AlbumColumns.ALBUM_ID)));
int pathcolumn = cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.DATA);
String path1 = cursor.getString(pathcolumn);
String album_url = null;
Uri sArtworkUri = Uri.parse("content://media/external/audio/albumart");
Uri uri = ContentUris.withAppendedId(sArtworkUri, ALBUM_ID);
album_url = uri.toString();
ContentResolver res = this.getContentResolver();
// Album
String album_name = cursor.getString(cursor.getColumnIndex(MediaStore.Audio.AlbumColumns.ALBUM));
String year = cursor.getString(cursor.getColumnIndex(MediaStore.Audio.AudioColumns.YEAR));
// String year = cursor.getString(cursor.getColumnIndex(MediaStore.Audio.AlbumColumns.NUMBER_OF_SONGS));
// artist
String artist_name = cursor.getString(cursor.getColumnIndex(MediaStore.Audio.ArtistColumns.ARTIST));
// display name
String DisplayName = cursor.getString(cursor.getColumnIndex(MediaStore.MediaColumns.DISPLAY_NAME));
//title
String Title = cursor.getString(cursor.getColumnIndex(MediaStore.MediaColumns.TITLE));
songtitle.add(Title);
Collections.sort(songtitle);
artistname.add(songtitle.indexOf(Title), artist_name);
albumname.add(songtitle.indexOf(Title), album_name);
path.add(songtitle.indexOf(Title),path1);
albumartwork.add(songtitle.indexOf(Title),album_url);
j++;
}while(cursor.moveToNext());
}
Collections.sort(songtitle);
adapter = new ArrayAdapter<String>(this,R.layout.song,songtitle);
setListAdapter(adapter);
}
My Question is i want to insert Dividers whenever the first letter of the SongName Changes.
I have this method to get the first letter of the songname if it is different than the previous..
private void alphebetdividers(ArrayList<String> songtitle2) {
String newString = null;
// TODO Auto-generated method stub
ArrayList<Character> letters = new ArrayList<Character>();
int i = 0;
int j = 0;
while( j < songtitle.size()-1){
if(songtitle2.get(i).charAt(0) == songtitle2.get(i+1).charAt(0)){
Toast.makeText(getApplication(), songtitle2.get(i).charAt(0) + "== " + songtitle2.get(i+1).charAt(0), Toast.LENGTH_LONG).show();
}else{
// Display Char with TextView
String songName = songtitle2.get(i);
newString = songName.substring(0, 1);
}
j++;
i++;
}
How would i display this in the list view at the appropriate spots. Thank you and i will give u a good rating if u know the answer.
You probably want an Adapter that implements SectionIndexer, specifically AlphabetIndexer. See this or this.
You really should be using an Adapter... there are libraries that do all of this work for you, you shouldn't have to do it yourself in a massive loop!
Here is some sample code to help you get started... note that it is a little out-dated in that it makes use of some deprecated methods (such as managedQuery, etc.). If you wanted to be entirely 100% correct you would want to make use of the LoaderManager.LoaderCallbacks<Cursor interface introduced in the Honeycomb release, but it's a good start.
To sort the displayed views, you can make use of the sortOrder argument in the ContentProvider's query method.
Pretty sure this is an easy one, but i'm getting confused by all the examples that adapt the data returned from a cursor into different views. I just want to run a rawquery and put each item of data returned into a float array (so that i can add them up later). What do i need to use for this? Thanks
You'll still have a cursor when you query your database, but once you got the cursor you could iterate over it, pulling out the values you need into an array, like this:
DbAdapter db = new DbAdapter(mContext);
int columnIndex = 3; // Whichever column your float is in.
db.open();
Cursor cursor = db.getAllMyFloats();
float[] myFloats = new float[cursor.getCount()-1];
if (cursor.moveToFirst())
{
for (int i = 0; i < cursor.getCount(); i++)
{
myFloats[i] = cursor.getFloat(columnIndex);
cursor.moveToNext();
}
}
cursor.close();
db.close();
// Do what you want with myFloats[].
Don't minus by 1 in float[] myFloats = new float[cursor.getCount()-1]; because (int i =0) or i start from 0. If you use it, will appear Java.lang.IndexOutOfBoundsException. You need array index until [cursor.getCount()], not until [cursor.getCount()-1]. So the correct thing is float[] myFloats = new float[cursor.getCount()];
I have created a simple Spinner binding it to a SimpleCursorAdapter. I'm populating the SimpleCursorAdapter with a list of towns from a content provider.
When I go to save the users selection I'm planning on saving the row id that is being populated into my SimpleCursorAdapter.
I'm using the following code to get the ID.
townSpinner.getSelectedItemId();
What I can not figure out is how best to set the selection when I pull back up the saved item.
The following code works but it only sets selection by position number.
townSpinner.setSelection(2);
Should I just create a loop to determine the correct position value based on Id?
long cityId = Long.parseLong(cursor.getString(CityQuery.CITY_ID));
for (int i = 0; i < citySpinner.getCount(); i++) {
long itemIdAtPosition2 = citySpinner.getItemIdAtPosition(i);
if (itemIdAtPosition2 == cityId) {
citySpinner.setSelection(i);
break;
}
}
I think you've answered your own question there!
Just write your own setSelectionByItemId method using the code you posted
Example:
DB:
public Cursor getData() {
SQLiteDatabase db = getReadableDatabase();
String sql = "select ID _id, Name from MyTable order by Name ";
Cursor c = db.rawQuery(sql, null);
c.moveToFirst();
return c;
}
Activity:
Cursor myCursor = db.getData();
SimpleCursorAdapter adapter1 = new SimpleCursorAdapter(
this,
android.R.layout.simple_spinner_item,
myCursor,
new String[] { "Name" }, new int[] { android.R.id.text1 }, 0);
adapter1.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
mySpinner.setAdapter(adapter1);
for(int i = 0; i < adapter1.getCount(); i++)
{
if (adapter1.getItemId(i) == myID )
{
mySpinner.setSelection(i, false); //(false is optional)
break;
}
}
Android Spinner set Selected Item by Value
The spinner provides a way to set the selected valued based on the position using the setSelection(int position) method. Now to get the position based on a value you have to loop thru the spinner and get the position. Here is an example
mySpinner.setSelection(getIndex(mySpinner, myValue));
private int getIndex(Spinner spinner, String myString){
int index = 0;
for (int i=0;i<spinner.getCount();i++){
if (spinner.getItemAtPosition(i).equals(myString)){
index = i;
}
}
return index;
}
If you are using an ArrayList for your Spinner Adapter then you can use that to loop thru and get the index. Another way is is to loop thru the adapter entries
Spinner s = (Spinner) findViewById(R.id.spinner_id);
for(i=0; i < adapter.getCount(); i++) {
if(myString.trim().equals(adapter.getItem(i).toString())){
s.setSelection(i);
break;
}
}