点击一个控件后，在屏幕中央
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弹出一个类似menu菜单栏
package com.example.contextmenu;
import android.app.Activity;
import android.content.Context;
import android.content.res.Resources;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.SubMenu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.Toast;
public class ContextActivity extends Activity implements OnClickListener{
private final int CONTEXT_MENU_ID = 1;
private static final int CTX_MENU_ITEM_ADD = Menu.FIRST;//
private static final int CTX_MENU_ITEM_DELETE = Menu.FIRST + 1;
private static final int CTX_MENU_ITEM_FIND = Menu.FIRST + 2;
private IconContextMenu iconContextMenu;
private Button btn;
private Context mContext;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_context);
mContext = this;
btn = (Button) findViewById(R.id.button1);
btn.setOnClickListener(this);
}
private void showContext(){
Resources res = getResources();
// init the menu
if (iconContextMenu == null)
iconContextMenu = new IconContextMenu(this, CONTEXT_MENU_ID);
iconContextMenu.clearItems();
R.drawable.revert, CTX_MENU_ITEM_ADD);
iconContextMenu.addItem(res, getText(R.string.delete),//
R.drawable.play , CTX_MENU_ITEM_DELETE);
iconContextMenu.addItem(res, getText(R.string.find),//
R.drawable.question, CTX_MENU_ITEM_FIND);
iconContextMenu.setOnClickListener(new IconContextMenu.IconContextMenuOnClickListener() {
@Override
public void onClick(int menuId) {
// TODO Auto-generated method stub
String str = "null";
switch(menuId){
case CTX_MENU_ITEM_ADD:
str = "增加";
break;
case CTX_MENU_ITEM_DELETE:
str = "删除";
break;
case CTX_MENU_ITEM_FIND:
str = "查找";
break;
}
Log.v("iconcontext", str);
Toast.makeText(mContext, str, Toast.LENGTH_SHORT).show();
}
});
}
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
if(arg0.equals(btn)){
showContext();
iconContextMenu.createMenu("IconContextMenu").show();
}
}
}
//封装的类IconContextMenu
package com.example.contextmenu;
import java.util.ArrayList;
import android.app.Activity;
import android.app.AlertDialog;
import android.app.Dialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.res.Resources;
import android.content.res.Resources.Theme;
import android.graphics.Color;
import android.graphics.drawable.Drawable;
import android.util.TypedValue;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AbsListView;
import android.widget.BaseAdapter;
import android.widget.TextView;
public class IconContextMenu implements DialogInterface.OnCancelListener, DialogInterface.OnDismissListener {
//private static final int Build_VERSION_CODES_ICE_CREAM_SANDWICH = 14;
private static final int LIST_PREFERED_HEIGHT = 85;
private IconMenuAdapter menuAdapter = null;
private Activity parentActivity = null;
private IconContextMenuOnClickListener clickHandler = null;
/**
* constructor
*
* @param parent
* @param id
*/
public IconContextMenu(Activity parent, int id) {
this.parentActivity = parent;
menuAdapter = new IconMenuAdapter(parentActivity);
}
/**
* Add menu item
*
* @param menuItem
*/
public void addItem(Resources res, CharSequence title, int p_w_picpathResourceId, int actionTag) {
menuAdapter.addItem(new IconContextMenuItem(res, title, p_w_picpathResourceId, actionTag));
}
public void addItem(Resources res, int textResourceId, int p_w_picpathResourceId, int actionTag) {
menuAdapter.addItem(new IconContextMenuItem(res, textResourceId, p_w_picpathResourceId, actionTag));
}
public void clearItems() {
menuAdapter.clearItems();
}
/**
* Set menu onclick listener
*
* @param listener
*/
public void setOnClickListener(IconContextMenuOnClickListener listener) {
clickHandler = listener;
}
/**
* Create menu
*
* @return
*/
public Dialog createMenu(String menuItitle) {
final AlertDialog.Builder builder = new AlertDialog.Builder(parentActivity);
builder.setTitle(menuItitle);
builder.setAdapter(menuAdapter, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialoginterface, int i) {
IconContextMenuItem item = (IconContextMenuItem) menuAdapter.getItem(i);
if (clickHandler != null) {
clickHandler.onClick(item.actionTag);
}
}
});
builder.setInverseBackgroundForced(true);
AlertDialog dialog = builder.create();
dialog.setOnCancelListener(this);
dialog.setOnDismissListener(this);
return dialog;
}
public void onCancel(DialogInterface dialog) {
cleanup();
}
public void onDismiss(DialogInterface dialog) {
}
private void cleanup() {
// parentActivity.dismissDialog(dialogId);
}
/**
* IconContextMenu On Click Listener interface
*/
public interface IconContextMenuOnClickListener {
public abstract void onClick(int menuId);
}
/**
* Menu-like list adapter with icon
*/
protected class IconMenuAdapter extends BaseAdapter {
private Context context = null;
private ArrayList
public IconMenuAdapter(Context context) {
this.context = context;
}
/**
* add item to adapter
*
* @param menuItem
*/
public void addItem(IconContextMenuItem menuItem) {
mItems.add(menuItem);
}
public void clearItems() {
mItems.clear();
}
@Override
public int getCount() {
return mItems.size();
}
@Override
public Object getItem(int position) {
return mItems.get(position);
}
@Override
public long getItemId(int position) {
IconContextMenuItem item = (IconContextMenuItem) getItem(position);
return item.actionTag;
}
@SuppressWarnings("deprecation")
@Override
public View getView(int position, View convertView, ViewGroup parent) {
IconContextMenuItem item = (IconContextMenuItem) getItem(position);
Resources res = parentActivity.getResources();
if (convertView == null) {
TextView temp = new TextView(context);
AbsListView.LayoutParams param = new AbsListView.LayoutParams(AbsListView.LayoutParams.FILL_PARENT,
AbsListView.LayoutParams.WRAP_CONTENT);
temp.setLayoutParams(param);
temp.setPadding((int) toPixel(res, 15), 0, (int) toPixel(res, 15), 0);
temp.setGravity(android.view.Gravity.CENTER_VERTICAL);
Theme th = context.getTheme();
TypedValue tv = new TypedValue();
if (th.resolveAttribute(android.R.attr.textAppearanceLargeInverse, tv, true)) {
temp.setTextAppearance(context, tv.resourceId);
}
temp.setMinHeight(LIST_PREFERED_HEIGHT);
temp.setCompoundDrawablePadding((int) toPixel(res, 20));
convertView = temp;
}
TextView textView = (TextView) convertView;
textView.setTag(item);
textView.setText(item.text);
textView.setTextColor(Color.BLACK);//刚开始，这里没有为自体设置颜色，导致文字看不出来
textView.setCompoundDrawablesWithIntrinsicBounds(item.p_w_picpath, null, null, null);
return textView;
}
private float toPixel(Resources res, int dip) {
float px = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dip, res.getDisplayMetrics());
return px;
}
}
/**
* menu-like list item with icon
*/
protected class IconContextMenuItem {
public final CharSequence text;
public final Drawable p_w_picpath;
public final int actionTag;
/**
* public constructor
*
* @param res
* resource handler
* @param textResourceId
* id of title in resource
* @param p_w_picpathResourceId
* id of icon in resource
* @param actionTag
* indicate action of menu item
*/
public IconContextMenuItem(Resources res, int textResourceId, int p_w_picpathResourceId, int actionTag) {
text = res.getString(textResourceId);
if (p_w_picpathResourceId != -1) {
p_w_picpath = res.getDrawable(p_w_picpathResourceId);
} else {
p_w_picpath = null;
}
this.actionTag = actionTag;
}
/**
* public constructor
*
* @param res
* resource handler
* @param title
* menu item title
* @param p_w_picpathResourceId
* id of icon in resource
* @param actionTag
* indicate action of menu item
*/
public IconContextMenuItem(Resources res, CharSequence title, int p_w_picpathResourceId, int actionTag) {
text = title;
if (p_w_picpathResourceId != -1) {
p_w_picpath = res.getDrawable(p_w_picpathResourceId);
} else {
p_w_picpath = null;
}
this.actionTag = actionTag;
}
}
}
//activity_context.xml 里面只有一个Button按钮
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context=".ContextActivity" > android:id="@+id/button1" android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="Button" />