ListView (Android SDK)

Transcript

1. MATC89: Aplicações para Dispositivos Móveis Universidade Federal da Bahia (UFBA) Rodrigo Rocha e Christina von Flach 2012.2 ListView Android SDK
2. Tópicos 1. ListView e ArrayAdapter 2. Adapter Personalizado 3. Reuso de Células 4. Padrão Holder 5. Interação e ListActivity
3. ListView
4. ListView ListView
5. ListView ListView Rolagem!
6. ListView ListView Célula (layout) Rolagem!
7. ListAdapter
8. ListAdapter Modelo
9. ListAdapter Modelo ListAdapter ListView
10. Layout (.xml)
11. Layout (.xml) <RelativeLayout ... > <ListView android:id="@+id/listView" android:layout_width="match_parent" android:layout_height="match_parent" android:layout_alignParentLeft="true" android:layout_alignParentTop="true" > </ListView> </RelativeLayout> activity_main.xml
12. Activity (.java)
13. Activity (.java) MainActivity.java public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } }
14. Activity (.java) MainActivity.java public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } }
15. Activity (.java) MainActivity.java private ListView listView; public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } }
16. Activity (.java) MainActivity.java private ListView listView; public class MainActivity extends Activity { @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } } listView = (ListView)findViewById(R.id.listView);
17. ArrayAdapter MainActivity.java private ListView listView; public class MainActivity extends Activity { // ...
18. ArrayAdapter MainActivity.java private ListView listView; public class MainActivity extends Activity { // ... private ArrayAdapter<String> listAdapter;
19. ArrayAdapter MainActivity.java private ListView listView; public class MainActivity extends Activity { private String[] contatos = {"João", "Zé", "Ana"}; // ... private ArrayAdapter<String> listAdapter;
20. ArrayAdapter MainActivity.java private ListView listView; public class MainActivity extends Activity { private String[] contatos = {"João", "Zé", "Ana"}; // ... private ArrayAdapter<String> listAdapter; modelo
21. ArrayAdapter
22. ArrayAdapter MainActivity.java protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } listView = (ListView)findViewById(R.id.listView);
23. ArrayAdapter MainActivity.java protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } listView = (ListView)findViewById(R.id.listView);
24. ArrayAdapter MainActivity.java protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } listView = (ListView)findViewById(R.id.listView); listAdapter = new ArrayAdapter<String>( this, android.R.layout.simple_list_item_1, android.R.id.text1, contatos);
25. ArrayAdapter MainActivity.java protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } listView = (ListView)findViewById(R.id.listView); listAdapter = new ArrayAdapter<String>( this, android.R.layout.simple_list_item_1, android.R.id.text1, contatos); layout da célula
26. ArrayAdapter MainActivity.java protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } listView = (ListView)findViewById(R.id.listView); listAdapter = new ArrayAdapter<String>( this, android.R.layout.simple_list_item_1, android.R.id.text1, contatos); layout da célula id do TextView
27. ArrayAdapter MainActivity.java protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } listView = (ListView)findViewById(R.id.listView); listAdapter = new ArrayAdapter<String>( this, android.R.layout.simple_list_item_1, android.R.id.text1, contatos); layout da célula id do TextView modelo
28. ArrayAdapter MainActivity.java protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } listView = (ListView)findViewById(R.id.listView); listAdapter = new ArrayAdapter<String>( this, android.R.layout.simple_list_item_1, android.R.id.text1, contatos); layout da célula id do TextView modelo listView.setAdapter(listAdapter);
29. Resultado
30. Tópicos 1. ListView e ArrayAdapter 2. Adapter Personalizado 3. Reuso de Células 4. Padrão Holder 5. Interação e ListActivity
31. Adapter Personalizado String Adapter Array ListView
32. Adapter Personalizado Contato Adapter ListView
33. Adapter Personalizado Contato Adapter Contato ListView
34. Modelo Contato.java public class Contato { private long id; private String nome; private String telefone; public Contato(long id, String nome, String telefone) { this.id = id; this.nome = nome; this.telefone = telefone; } // getters e setters }
35. Modelo
36. Modelo MainActivity.java private ListView listView; public class MainActivity extends Activity { private String[] contatos = {"João", "Zé", "Ana"}; // ... private ArrayAdapter<String> listAdapter;
37. Modelo MainActivity.java private ListView listView; public class MainActivity extends Activity { private List<Contato> contatos = new ArrayList<Contato>(); // ... private ArrayAdapter<String> listAdapter;
38. Modelo TODO: Adicionar elementos a contatos 
 (em onCreate)
39. Adapter Personalizado ContatoAdapter.java
40. Adapter Personalizado ContatoAdapter.java public class ContatoAdapter extends ArrayAdapter<Contato> { public ContatoAdapter(Context context, List<Contato> contatos) { super(context, 0, contatos); } @Override public View getView(int position, View convertView, ViewGroup parent) { View view = null; return view; } // ... }
41. Adapter Personalizado ContatoAdapter.java public class ContatoAdapter extends ArrayAdapter<Contato> { public ContatoAdapter(Context context, List<Contato> contatos) { super(context, 0, contatos); } @Override public View getView(int position, View convertView, ViewGroup parent) { View view = null; return view; } // ... }
42. Adapter Personalizado ContatoAdapter.java public class ContatoAdapter extends ArrayAdapter<Contato> { public ContatoAdapter(Context context, List<Contato> contatos) { super(context, 0, contatos); } @Override public View getView(int position, View convertView, ViewGroup parent) { View view = null; return view; } // ... } salva o contexto e a lista
43. Adapter Personalizado ContatoAdapter.java public class ContatoAdapter extends ArrayAdapter<Contato> { public ContatoAdapter(Context context, List<Contato> contatos) { super(context, 0, contatos); } @Override public View getView(int position, View convertView, ViewGroup parent) { View view = null; return view; } // ... } cria uma view para cada célula salva o contexto e a lista
44. Adapter Personalizado ContatoAdapter.java @Override public View getView(int position, View convertView, ViewGroup parent) { View view = null; return view; }
45. Adapter Personalizado ContatoAdapter.java @Override public View getView(int position, View convertView, ViewGroup parent) { View view = null; return view; } Contato contato = getItem(position); if (contato != null) { } definido em ArrayAdapter
46. Adapter Personalizado ContatoAdapter.java @Override public View getView(int position, View convertView, ViewGroup parent) { View view = null; return view; } Contato contato = getItem(position); if (contato != null) { } LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); definido em ArrayAdapter
47. Adapter Personalizado ContatoAdapter.java @Override public View getView(int position, View convertView, ViewGroup parent) { View view = null; return view; } Contato contato = getItem(position); if (contato != null) { } LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); TextView text1 = (TextView)view.findViewById(android.R.id.text1); TextView text2 = (TextView)view.findViewById(android.R.id.text2); definido em ArrayAdapter
48. Adapter Personalizado ContatoAdapter.java @Override public View getView(int position, View convertView, ViewGroup parent) { View view = null; return view; } Contato contato = getItem(position); if (contato != null) { } LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); text1.setText(contato.getNome()); text2.setText(contato.getTelefone()); TextView text1 = (TextView)view.findViewById(android.R.id.text1); TextView text2 = (TextView)view.findViewById(android.R.id.text2); definido em ArrayAdapter
49. Modelo TODO: Editar MainActivity 
 para usar ContactAdapter
50. Tópicos 1. ListView e ArrayAdapter 2. Adapter Personalizado 3. Reuso de Células 4. Padrão Holder 5. Interação e ListActivity
51. Reuso de Células
52. Reuso de Células getView(0, ...) João
53. Reuso de Células getView(0, ...) João getView(1, ...) Zé
54. Reuso de Células getView(0, ...) João getView(1, ...) Zé getView(2, ...) Ana
55. Reuso de Células getView(0, ...) João getView(1, ...) Zé getView(2, ...) Ana getView(3, ...) Maria
56. Reuso de Células getView(0, ...) João getView(1, ...) Zé getView(2, ...) Ana getView(3, ...) Maria
57. Reuso de Células João Zé Ana Maria
58. Reuso de Células João Zé Ana Maria getView(4, ...)
59. Reuso de Células João Zé Ana Maria getView(4, ...)
60. Reuso de Células João Zé Ana Maria getView(4, ...)
61. Reuso de Células João Zé Ana Maria getView(4, ...) Fulano
62. Reuso de Células
63. Reuso de Células ContatoAdapter.java @Override public View getView(int position, View convertView, ViewGroup parent) { View view = return view; } Contato contato = getItem(position); if (contato != null) { LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); text1.setText(contato.getNome()); text2.setText(contato.getTelefone()); TextView text1 = (TextView)view.findViewById(android.R.id.text1); TextView text2 = (TextView)view.findViewById(android.R.id.text2); null; }
64. Reuso de Células ContatoAdapter.java @Override public View getView(int position, View convertView, ViewGroup parent) { View view = return view; } Contato contato = getItem(position); if (contato != null) { LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); text1.setText(contato.getNome()); text2.setText(contato.getTelefone()); TextView text1 = (TextView)view.findViewById(android.R.id.text1); TextView text2 = (TextView)view.findViewById(android.R.id.text2); ; }
65. Reuso de Células ContatoAdapter.java @Override public View getView(int position, View convertView, ViewGroup parent) { View view = return view; } Contato contato = getItem(position); if (contato != null) { LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); text1.setText(contato.getNome()); text2.setText(contato.getTelefone()); TextView text1 = (TextView)view.findViewById(android.R.id.text1); TextView text2 = (TextView)view.findViewById(android.R.id.text2); ; } convertView
66. Reuso de Células ContatoAdapter.java @Override public View getView(int position, View convertView, ViewGroup parent) { View view = return view; } Contato contato = getItem(position); if (contato != null) { LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); text1.setText(contato.getNome()); text2.setText(contato.getTelefone()); TextView text1 = (TextView)view.findViewById(android.R.id.text1); TextView text2 = (TextView)view.findViewById(android.R.id.text2); ; } if (view == null) { } convertView
67. Reuso de Células ContatoAdapter.java @Override public View getView(int position, View convertView, ViewGroup parent) { View view = return view; } Contato contato = getItem(position); if (contato != null) { LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); text1.setText(contato.getNome()); text2.setText(contato.getTelefone()); TextView text1 = (TextView)view.findViewById(android.R.id.text1); TextView text2 = (TextView)view.findViewById(android.R.id.text2); ; } if (view == null) { } convertView lento!
68. Tópicos 1. ListView e ArrayAdapter 2. Adapter Personalizado 3. Reuso de Células 4. Padrão Holder 5. Interação e ListActivity
69. Padrão Holder ContatoAdapter.java public class ContatoAdapter extends ArrayAdapter<Contato> { public ContatoAdapter(...) { ... } public View getView(...) { ... } }
70. Padrão Holder ContatoAdapter.java public class ContatoAdapter extends ArrayAdapter<Contato> { public ContatoAdapter(...) { ... } public View getView(...) { ... } }
71. Padrão Holder ContatoAdapter.java public class ContatoAdapter extends ArrayAdapter<Contato> { public ContatoAdapter(...) { ... } public View getView(...) { ... } static class ViewHolder { public TextView textNome; public TextView textTelefone; } }
72. Padrão Holder
73. Padrão Holder ContatoAdapter.java @Override public View getView(int position, View convertView, ViewGroup parent) { View view = return view; } Contato contato = getItem(position); if (contato != null) { LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); ; } if (view == null) { convertView } TextView text1 = TextView text2 = (TextView)view.findViewById(android.R.id.text1); (TextView)view.findViewById(android.R.id.text2); text1 text2 .setText(contato.getNome()); .setText(contato.getTelefone());
74. Padrão Holder ContatoAdapter.java LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); text1 text2 TextView text1 = TextView text2 = if (view == null) { (TextView)view.findViewById(android.R.id.text1); (TextView)view.findViewById(android.R.id.text2); } .setText(contato.getNome()); .setText(contato.getTelefone());
75. Padrão Holder ContatoAdapter.java LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); text1 text2 TextView text1 = TextView text2 = if (view == null) { if só é executado durante a criação inicial de células (TextView)view.findViewById(android.R.id.text1); (TextView)view.findViewById(android.R.id.text2); } .setText(contato.getNome()); .setText(contato.getTelefone());
76. Padrão Holder ContatoAdapter.java LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); text1 text2 TextView text1 = TextView text2 = if (view == null) { if só é executado durante a criação inicial de células sempre é executado (TextView)view.findViewById(android.R.id.text1); (TextView)view.findViewById(android.R.id.text2); } .setText(contato.getNome()); .setText(contato.getTelefone());
77. Padrão Holder ContatoAdapter.java LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); if (view == null) { (TextView)view.findViewById(android.R.id.text1); (TextView)view.findViewById(android.R.id.text2); } text1 text2 .setText(contato.getNome()); .setText(contato.getTelefone());
78. Padrão Holder ContatoAdapter.java LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); if (view == null) { (TextView)view.findViewById(android.R.id.text1); (TextView)view.findViewById(android.R.id.text2); } ViewHolder holder = new ViewHolder(); text1 text2 .setText(contato.getNome()); .setText(contato.getTelefone());
79. Padrão Holder ContatoAdapter.java LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); if (view == null) { (TextView)view.findViewById(android.R.id.text1); (TextView)view.findViewById(android.R.id.text2); } ViewHolder holder = new ViewHolder(); holder.textNome = holder.textTelefone = text1 text2 .setText(contato.getNome()); .setText(contato.getTelefone());
80. Padrão Holder ContatoAdapter.java LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); if (view == null) { (TextView)view.findViewById(android.R.id.text1); (TextView)view.findViewById(android.R.id.text2); } ViewHolder holder = new ViewHolder(); holder.textNome = holder.textTelefone = view.setTag(holder); text1 text2 .setText(contato.getNome()); .setText(contato.getTelefone());
81. Padrão Holder ContatoAdapter.java LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); if (view == null) { (TextView)view.findViewById(android.R.id.text1); (TextView)view.findViewById(android.R.id.text2); } ViewHolder holder = new ViewHolder(); holder.textNome = holder.textTelefone = view.setTag(holder); .setText(contato.getNome()); .setText(contato.getTelefone());
82. Padrão Holder ContatoAdapter.java LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); if (view == null) { (TextView)view.findViewById(android.R.id.text1); (TextView)view.findViewById(android.R.id.text2); } ViewHolder holder = new ViewHolder(); holder.textNome = holder.textTelefone = view.setTag(holder); .setText(contato.getNome()); .setText(contato.getTelefone()); ViewHolder holder = (ViewHolder)view.getTag();
83. Padrão Holder ContatoAdapter.java LayoutInflater inflater = (LayoutInflater)getContext() .getSystemService(Context.LAYOUT_INFLATER_SERVICE); view = inflater.inflate(android.R.layout.simple_list_item_2, null); if (view == null) { (TextView)view.findViewById(android.R.id.text1); (TextView)view.findViewById(android.R.id.text2); } ViewHolder holder = new ViewHolder(); holder.textNome = holder.textTelefone = view.setTag(holder); .setText(contato.getNome()); .setText(contato.getTelefone()); holder.textNome holder.textTelefone ViewHolder holder = (ViewHolder)view.getTag();
84. Tópicos 1. ListView e ArrayAdapter 2. Adapter Personalizado 3. Reuso de Células 4. Padrão Holder 5. Interação e ListActivity
85. Interação
86. Interação MainActivity.java listView.setOnItemClickListener(new OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { Contato contato = (Contato)listView.getItemAtPosition(position); String mensagem = "Oi, " + contato.getNome(); Toast.makeText(MainActivity.this, mensagem, Toast.LENGTH_SHORT) .show(); } });
87. ListActivity • extends ListActivity • getListView(...) • setListAdapter(...) • @Override onListItemClick(...)
88. CursorAdapter