package com.tpg.androidindexbar;
import java.util.ArrayList;
import android.content.Context;
import android.content.res.Resources;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.util.TypedValue;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;
public class IndexBarHandler extends Handler {
IndexBar indexbar;
static String TAG="IndexBarHandler";
int height_of_listview=0;
int height_of_alphabet_row=0;
int number_of_characters_shown=0;
int number_of_characters_omit=0;
int height_of_one_dot=0;
/**
* Constructor of IndexBarHandler class which reserves the instance reference of its UI class
* @param indexbar
*/
public IndexBarHandler(IndexBar indexbar) {
this.indexbar=indexbar;
}
public void handleMessage(Message msg) {
if (msg.what == 1) {
Log.d(TAG,"IndexBarHandler called. Custom Listview is created. Now initializing Alphabet IndexBar Scroller Listview.");
/*Before creating the Index Bar Listview we need to determine the number of alphabets
* to be shown in this listview.
*/
height_of_listview = (Integer)msg.obj; //Height of the ListView in pixels
View view=indexbar.findViewById(R.id.alphabet_row_layout);
if(view !=null && view instanceof TextView){
TextView row=(TextView)view;
height_of_alphabet_row=row.getHeight(); //Height of the row.
indexbar.getSharedPreferences("AndroidIndexBar", Context.MODE_PRIVATE).edit().putInt("height", height_of_alphabet_row).commit();
view.setVisibility(View.GONE);
}
else
return;
Log.d(TAG,"Height of List= "+height_of_listview+" height of one row="+height_of_alphabet_row);
number_of_characters_shown=height_of_listview/height_of_alphabet_row; //Number of Characters to be shown
number_of_characters_omit=26-number_of_characters_shown; //Number of Characters to be omited
Log.d(TAG,"Number of Characters="+number_of_characters_shown+" omits="+number_of_characters_omit);
//Alphabets listview is populated
ListView alphabets_listview=(ListView)indexbar.findViewById(R.id.listView_alphabets);
/*Populating the Alphabet List*/
ArrayList<String> alphabets_list=new ArrayList<String>();
String alphabet_array[] = indexbar.getResources().getStringArray(R.array.alphabtes_array);
for(int i=0; i<26 ; i++){
alphabets_list.add(alphabet_array[i]);
}
/*Main Task*/
prepareArray(alphabets_list);
ArrayAdapter<String> alphabets_adapter= new AlphabetListviewAdapter(indexbar.getBaseContext(),R.layout.alphabtes_row,alphabets_list, number_of_characters_omit);
alphabets_listview.setAdapter(alphabets_adapter);
alphabets_listview.setOnItemClickListener(indexbar);
}
}
private void prepareArray(ArrayList<String> alphabets_list) {
height_of_one_dot=convertDipToPx(9, indexbar.getBaseContext());
Log.d(TAG,"Height of one dot i.e. 9dp= "+height_of_one_dot+" px"); //9dp=13px
if(number_of_characters_omit==1 || number_of_characters_omit==2 ){
//adjusted the height of the row
}
if(number_of_characters_omit<=4){ //Two groups shown. For 3,4 characters remove 4,5 characters
removeAlphabet(alphabets_list, 5, 2); //F,G
alphabets_list.add(5, ".");
removeAlphabet(alphabets_list, 17, 2); //S,T
if(number_of_characters_omit==4)
alphabets_list.remove(17); //U
alphabets_list.add(17, ".");
}
if(number_of_characters_omit>4 & number_of_characters_omit<=6){ //5,6
int total_height_dots=height_of_one_dot*3;
float num_eliminate=(float)total_height_dots/height_of_alphabet_row;
int eliminate=(int)Math.round(num_eliminate+0.5f );
Log.d(TAG,"For 3 dots, eliminate= "+eliminate+" more characters"+" (num_eliminate="+num_eliminate+")");
if(eliminate==0) //there would be atleast one omitance. If there is any error, it is explicitly done.
eliminate=1;
if((number_of_characters_omit==5 && eliminate==2) || (number_of_characters_omit==6 && eliminate==1)) {
}
removeAlphabet(alphabets_list, 5, 2); //F,G
alphabets_list.add(5, ".");
alphabets_list.remove(13); //O
if(number_of_characters_omit==6)
alphabets_list.remove(13); //P
alphabets_list.add(13, ".");
if(number_of_characters_omit==5){
removeAlphabet(alphabets_list, 22, 2); //X,Y
alphabets_list.add(22, ".");
}else{
removeAlphabet(alphabets_list, 21, 2);
alphabets_list.add(21, ".");
}
if(eliminate==1)
alphabets_list.remove(14); //P / Q
else if(eliminate==2){
if(number_of_characters_omit==5){
removeAlphabet(alphabets_list, 14, 2); //P,Q
}
else{
alphabets_list.remove(6); //H
alphabets_list.remove(13); //Q
}
}
else{
if(number_of_characters_omit==5){
alphabets_list.remove(6); //H
removeAlphabet(alphabets_list, 13, 2); //P,Q
}
else{
alphabets_list.remove(6); //H
alphabets_list.remove(13); //Q
alphabets_list.remove(18); //W
}
}
}
else if(number_of_characters_omit>6 & number_of_characters_omit<=8){
int total_height_dots=height_of_one_dot*4;
float num_eliminate=(float)total_height_dots/height_of_alphabet_row;
int eliminate=(int)Math.round(num_eliminate+0.5f );
Log.d(TAG,"For 4 dots, eliminate= "+eliminate+" rows"+" (num_eliminate="+num_eliminate+")");
if(eliminate==0) //there would be atleast one omitance. If there is any error, it is explicitly done.
eliminate=1;
if( (number_of_characters_omit==7 && eliminate==2) || (number_of_characters_omit==8 && eliminate==1)){
removeAlphabet(alphabets_list, 2, 3); //C,D,E
alphabets_list.add(2,".");
removeAlphabet(alphabets_list, 7, 2); //J,K
alphabets_list.add(7,".");
removeAlphabet(alphabets_list, 13, 2); //Q,R
alphabets_list.add(13,".");
removeAlphabet(alphabets_list, 19, 2); //X,Y
alphabets_list.add(19,".");
}
else if( (number_of_characters_omit==7 && eliminate==3) || (number_of_characters_omit==8 && eliminate==2)){
removeAlphabet(alphabets_list, 2, 3); //C,D,E
alphabets_list.add(2,".");
removeAlphabet(alphabets_list, 6, 3); //I,J,K
alphabets_list.add(6,".");
removeAlphabet(alphabets_list, 12, 2); //Q,R
alphabets_list.add(12,".");
removeAlphabet(alphabets_list, 18, 2); //X,Y
alphabets_list.add(18,".");
}
else if( (number_of_characters_omit==7 && eliminate==4) || (number_of_characters_omit==8 && eliminate==3)){
removeAlphabet(alphabets_list, 2, 3); //C,D,E
alphabets_list.add(2,".");
removeAlphabet(alphabets_list, 6, 3); //I,J,K
alphabets_list.add(6,".");
removeAlphabet(alphabets_list, 11, 3); //P,Q,R
alphabets_list.add(11,".");
removeAlphabet(alphabets_list, 17, 2); //X,Y
alphabets_list.add(17,".");
}
else if( number_of_characters_omit==7 && eliminate==1){
removeAlphabet(alphabets_list, 3, 2); //D,E
alphabets_list.add(3,".");
removeAlphabet(alphabets_list, 8, 2); //J,K
alphabets_list.add(8,".");
removeAlphabet(alphabets_list, 14, 2); //Q,R
alphabets_list.add(14,".");
removeAlphabet(alphabets_list, 20, 2); //X,Y
alphabets_list.add(20,".");
}
else if( number_of_characters_omit==8 && eliminate==4){
removeAlphabet(alphabets_list, 2, 3); //C,D,E
alphabets_list.add(2,".");
removeAlphabet(alphabets_list, 6, 3); //I,J,K
alphabets_list.add(6,".");
removeAlphabet(alphabets_list, 11, 3);
alphabets_list.add(11,".");
removeAlphabet(alphabets_list, 16, 3); //W,X,Y
alphabets_list.add(16,".");
}
}
}
public int convertDipToPx(int dp, Context context){ //10dp=15px
Resources r = context.getResources();
float px = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dp, r.getDisplayMetrics());
return (int)px;
}
/**
* This method eliminates the character on remove_position from ArrayList list for iterations number of times.
* @param list
* @param remove_position
* @param iterations
*/
private void removeAlphabet(ArrayList<String>list, int remove_position, int iterations){
if(list==null || remove_position>list.size() || iterations==0)
return;
for (int i=0; i<iterations; i++){
list.remove(remove_position);
}
}
}
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