編輯:關於Android編程
菜單功能是點擊按鈕彈出分類菜單
看看效果圖

先說一下實現原理,彈出菜單采用的是Fragment實現,很方便且高效,上面的三個按鈕是RadioButton。
新建一個項目FragmentMenu
主界面activity_main.xml
布局文件我這裡說一下,RadioGroup裡面是RadioButton,使用這個主要是為了控制選中按鈕背景色,使用RadioGroup之後就不必在代碼中手動設置選中按鈕背景色。緊接著的一個空白的LinearLayout,它是個容器,後面的Fragment就是裝載這個裡面的。下面的是一個ListView,在這個例子中我沒有使用它。android:gravity=center android:textSize=18sp /> android:textSize=18sp /> android:textSize=18sp />
selector_radio_back.xml
看一下MainActivity的主要代碼
/**
* 初始化控件
*/
private void init() {
// TODO Auto-generated method stub
group = (RadioGroup) findViewById(R.id.group);
kindBtn = (RadioButton) findViewById(R.id.kind);
kindBtn.setOnClickListener(this);
distanceBtn = (RadioButton) findViewById(R.id.distance);
distanceBtn.setOnClickListener(this);
sortBtn = (RadioButton) findViewById(R.id.sort);
sortBtn.setOnClickListener(this);
}
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch (v.getId()) {
case R.id.kind:
getSupportFragmentManager().beginTransaction()
.replace(R.id.fragment_container, kindFragment).commit();
fragment = kindFragment;
break;
case R.id.distance:
getSupportFragmentManager().beginTransaction()
.replace(R.id.fragment_container, distanceFragment)
.commit();
fragment = distanceFragment;
break;
case R.id.sort:
getSupportFragmentManager().beginTransaction()
.replace(R.id.fragment_container, sortFragment).commit();
fragment = sortFragment;
break;
}
}
在OnClick方法中把Fragment給加載出來,你在主界面所要做的幾乎就是這麼多,後面的菜單點擊事件就完全的交給各個Fragment來實現,這樣做各個Fragment之間結構泾渭分明,不易出錯,也易於以後的維護。
MainActivity全部代碼
package com.example.fragmentmenu;
import android.os.Bundle;
import android.os.Handler;
import android.os.Message;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.view.KeyEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.Toast;
public class MainActivity extends FragmentActivity implements OnClickListener {
private RadioGroup group;
private RadioButton kindBtn, distanceBtn, sortBtn;
private KindFragment kindFragment;
private DistanceFragment distanceFragment;
private SortFragment sortFragment;
private Fragment fragment;
/**
* 用於接收從Fragment中發送來的消息
*/
private Handler handler = new Handler() {
@Override
public void handleMessage(Message msg) {
// TODO Auto-generated method stub
super.handleMessage(msg);
switch (msg.what) {
case 0:// 分類發來的消息
Toast.makeText(MainActivity.this, msg.obj.toString(),
Toast.LENGTH_SHORT).show();
getSupportFragmentManager().beginTransaction().remove(fragment)
.commit();
fragment = null;
group.clearCheck();
break;
case 1:// 范圍發來的消息
Toast.makeText(MainActivity.this, msg.obj.toString(),
Toast.LENGTH_SHORT).show();
getSupportFragmentManager().beginTransaction().remove(fragment)
.commit();
fragment = null;
group.clearCheck();
break;
case 2:// 排序發來的消息
Toast.makeText(MainActivity.this, msg.obj.toString(),
Toast.LENGTH_SHORT).show();
getSupportFragmentManager().beginTransaction().remove(fragment)
.commit();
fragment = null;
group.clearCheck();
break;
}
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
kindFragment = new KindFragment();
kindFragment.setHandler(handler);
distanceFragment = new DistanceFragment();
distanceFragment.setHandler(handler);
sortFragment = new SortFragment();
sortFragment.setHandler(handler);
init();
}
/**
* 初始化控件
*/
private void init() {
// TODO Auto-generated method stub
group = (RadioGroup) findViewById(R.id.group);
kindBtn = (RadioButton) findViewById(R.id.kind);
kindBtn.setOnClickListener(this);
distanceBtn = (RadioButton) findViewById(R.id.distance);
distanceBtn.setOnClickListener(this);
sortBtn = (RadioButton) findViewById(R.id.sort);
sortBtn.setOnClickListener(this);
}
@Override
public void onClick(View v) {
// TODO Auto-generated method stub
switch (v.getId()) {
case R.id.kind:
getSupportFragmentManager().beginTransaction()
.replace(R.id.fragment_container, kindFragment).commit();
fragment = kindFragment;
break;
case R.id.distance:
getSupportFragmentManager().beginTransaction()
.replace(R.id.fragment_container, distanceFragment)
.commit();
fragment = distanceFragment;
break;
case R.id.sort:
getSupportFragmentManager().beginTransaction()
.replace(R.id.fragment_container, sortFragment).commit();
fragment = sortFragment;
break;
}
}
/**
* 監控手機返回按鍵,如果此時Fragment存在就把它移除,不存在就直接關閉界面
*/
@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
// TODO Auto-generated method stub
if (keyCode == KeyEvent.KEYCODE_BACK
&& event.getAction() == KeyEvent.ACTION_DOWN) {
if (fragment != null) {
getSupportFragmentManager().beginTransaction().remove(fragment)
.commit();
fragment = null;
group.clearCheck();
} else
finish();
return true;
}
return super.onKeyDown(keyCode, event);
}
}
關於Activity與Fragment的數據交互,有很多中實現方式,我這裡是使用了Handler來實現數據交互,在Fragment中處理完點擊事件之後會將處理結果發送到MainActivity以便於MainActivity繼續下面的操作(比如說給ListView賦值)。
看第一Fragment,也是這裡面最復雜的一個Fragment、新建一個Fragment名字叫KindFragment。
package com.example.fragmentmenu;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
public class KindFragment extends Fragment implements OnItemClickListener {
private ListView listView, detailListView;
private List list = new ArrayList(),
detaillist = new ArrayList();
private KindAdapter listAdapter, detailAdapter;
private Map map = new HashMap();
//用於保存選中的列表索引值
private int listSelect = -1, detailSelect = -1;
private Handler handler;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
View view = inflater.inflate(R.layout.fragment_kind, null);
initData();
init(view);
return view;
}
/**
* 初始化數據
*/
private void initData() {
// TODO Auto-generated method stub
map.put(快餐, R.array.kind_kuaichan);
map.put(中餐, R.array.kind_zhongchan);
map.put(西餐, R.array.kind_xichan);
if (list != null && list.size() > 0)
list.clear();
for (Map.Entry entry : map.entrySet())
list.add(entry.getKey().toString());
}
/**
* 初始化控件
*
* @param view
*/
private void init(View view) {
// TODO Auto-generated method stub
listView = (ListView) view.findViewById(R.id.kind_list);
listAdapter = new KindAdapter(getActivity());
listAdapter.setList(list);
listAdapter.setClickItem(listSelect);
listView.setAdapter(listAdapter);
listView.setOnItemClickListener(this);
detailListView = (ListView) view.findViewById(R.id.kind_detil_list);
detailAdapter = new KindAdapter(getActivity());
detailAdapter.setList(detaillist);
detailAdapter.setClickItem(detailSelect);
detailListView.setAdapter(detailAdapter);
detailListView.setOnItemClickListener(this);
}
/**
* 加載子列表數據
*
* @param key
* @return
*/
private boolean addDetailList(String key) {
if (detaillist != null && detaillist.size() > 0)
detaillist.clear();
String[] detailArray = getResources().getStringArray(map.get(key));
if (detailArray.length <= 0)
return false;
for (String str : detailArray)
detaillist.add(str);
return true;
}
/**
* ListView點擊事件
*/
@Override
public void onItemClick(AdapterView parent, View view, int position,
long id) {
// TODO Auto-generated method stub
if (parent.getId() == R.id.kind_list) {
listAdapter.setClickItem(position);
listAdapter.notifyDataSetChanged();
listSelect = position;
detailSelect = -1;
boolean hasDetail = addDetailList(list.get(position));
detailAdapter.setClickItem(-1);
detailAdapter.notifyDataSetChanged();
if (!hasDetail)// 將點擊結果發送到主界面
handler.obtainMessage(0, list.get(position)).sendToTarget();
} else if (parent.getId() == R.id.kind_detil_list) {
detailAdapter.setClickItem(position);
detailAdapter.notifyDataSetChanged();
detailSelect = position;
//將點擊結果發送到主界面
handler.obtainMessage(0, detaillist.get(position)).sendToTarget();
}
}
public void setHandler(Handler handler) {
this.handler = handler;
}
}
這個Fragment在這個項目裡是最復雜的Fragment,這也只是相對來說,從上面的代碼看,它並不復雜,之所以說它最復雜是因為後面的兩個Fragment更簡單。相關代碼我都有注釋,需要特別提出的一點是在adapter中添加了一個方法用於設置選中列表項的顏色。
private int clickItem = -1;;
public void setClickItem(int clickItem) {
this.clickItem = clickItem;
}
KindAdapter完整代碼
package com.example.fragmentmenu;
import java.util.List;
import android.content.Context;
import android.graphics.Color;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;
public class KindAdapter extends BaseAdapter {
private List list;
private LayoutInflater inflater;
public KindAdapter(Context context) {
inflater = (LayoutInflater) context
.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return list == null ? 0 : list.size();
}
public List getList() {
return list;
}
public void setList(List list) {
this.list = list;
}
@Override
public Object getItem(int position) {
// TODO Auto-generated method stub
return list == null ? null : list.get(position);
}
@Override
public long getItemId(int position) {
// TODO Auto-generated method stub
return list == null ? -1 : position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// TODO Auto-generated method stub
ViewHolder holder;
if (convertView == null) {
holder = new ViewHolder();
convertView = inflater
.inflate(R.layout.adapter_fragment_list, null);
holder.text = (TextView) convertView
.findViewById(R.id.adapter_kind_text);
convertView.setTag(holder);
} else
holder = (ViewHolder) convertView.getTag();
if (position != clickItem) {
convertView.setBackgroundColor(Color.WHITE);
} else {
convertView.setBackgroundColor(Color.LTGRAY);
}
holder.text.setText(list.get(position));
return convertView;
}
private int clickItem = -1;;
public void setClickItem(int clickItem) {
this.clickItem = clickItem;
}
class ViewHolder {
TextView text;
}
}
看一下布局文件
adapter_fragment_list.xml
KindFragment布局文件
fragment_kind.xml
很簡單,只有兩個ListView。
後面的兩個Fragment實現方式與之類似,我直接把代碼貼出來
DistanceFragment
package com.example.fragmentmenu;
import java.util.ArrayList;
import java.util.List;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
public class DistanceFragment extends Fragment implements OnItemClickListener {
private ListView listView;
private KindAdapter listAdapter;
private List list = new ArrayList();
private int listSelect = -1;
private Handler handler;
public void setHandler(Handler handler) {
this.handler = handler;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
View view = inflater.inflate(R.layout.fragment_distance, null);
initData();
init(view);
return view;
}
private void initData() {
// TODO Auto-generated method stub
if (list != null && list.size() > 0)
list.clear();
for (int i = 100; i < 105; i++)
list.add(String.valueOf(i));
}
private void init(View view) {
// TODO Auto-generated method stub
listView = (ListView) view.findViewById(R.id.diatnce_list);
listAdapter = new KindAdapter(getActivity());
listAdapter.setList(list);
listAdapter.setClickItem(listSelect);
listView.setAdapter(listAdapter);
listView.setOnItemClickListener(this);
}
@Override
public void onItemClick(AdapterView parent, View view, int position,
long id) {
// TODO Auto-generated method stub
listAdapter.setClickItem(position);
listAdapter.notifyDataSetChanged();
listSelect = position;
handler.obtainMessage(1, list.get(position)).sendToTarget();
}
}
fragment_distance.xml
SortFragment
package com.example.fragmentmenu;
import java.util.ArrayList;
import java.util.List;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ListView;
public class SortFragment extends Fragment implements OnItemClickListener {
private ListView listView;
private KindAdapter listAdapter;
private List list = new ArrayList();
private int listSelect = -1;
private Handler handler;
public void setHandler(Handler handler) {
this.handler = handler;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// TODO Auto-generated method stub
View view = inflater.inflate(R.layout.fragment_sort, null);
initData();
init(view);
return view;
}
private void initData() {
// TODO Auto-generated method stub
if (list != null && list.size() > 0)
list.clear();
for (int i = 0; i < 5; i++)
list.add(String.valueOf(i));
}
private void init(View view) {
// TODO Auto-generated method stub
listView = (ListView) view.findViewById(R.id.sort_list);
listAdapter = new KindAdapter(getActivity());
listAdapter.setList(list);
listAdapter.setClickItem(listSelect);
listView.setAdapter(listAdapter);
listView.setOnItemClickListener(this);
}
@Override
public void onItemClick(AdapterView parent, View view, int position,
long id) {
// TODO Auto-generated method stub
listAdapter.setClickItem(position);
listAdapter.notifyDataSetChanged();
listSelect = position;
handler.obtainMessage(2, list.get(position)).sendToTarget();
}
}
#d3d3d3
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