Android編程: 10月 2011

2011年10月19日星期三

Galaxy Nexus/Android 4.0 發佈會全記錄

谷歌/三星推出 Android 4.0 冰淇淋三明治 - 2011年10月19日，香港

2011年10月15日星期六

指定 Drawable 設定為列表視圖(ListView)的背景

<ListView
 android:id="@+id/list"
 android:layout_width="fill_parent"
 android:layout_height="wrap_content"
 android:background="@drawable/icon"
 android:cacheColorHint="#00000000" />

相關文章:
- 設定列表視圖(ListView)的背景顏色

設定列表視圖(ListView)的背景顏色

在佈局文件的 XML 中, 可通過列表視圖(ListView)的 android:background 和 android:cacheColorHint 以設定列表視圖的背景顏色.

<ListView
 android:id="@+id/list"
 android:layout_width="fill_parent"
 android:layout_height="wrap_content"
 android:background="#FF500000"
 android:cacheColorHint="#00000000" />

2011年10月14日星期五

2011年10月19日香港: Google + Samsung 正式公佈雪糕三明治(Ice Cream Sandwich)

Android 的官方YouTube頻道(http://www.youtube.com/android)已更新顯示:
10/19/2011 - 10 AM Hong Kong Time (HKT)

Live: YouTube.com/Android, 10/19/11, 10AM, Hong Kong Time (HKT)

Android谷歌翻譯(Google Translate)的對話模式(Conversation Mode)現支持更多語言, 包括中文.

除了原有的英語和西班牙語，Android谷歌翻譯(Google Translate)的對話模式(Conversation Mode)現在也支持巴西葡萄牙語，捷克語，荷蘭語，法語，德語，意大利語，日語，韓語，中文普通話，波蘭，俄羅斯和土耳其。

詳情: http://googlemobile.blogspot.com/2011/10/start-conversation-with-google.html

Android Market的下載鏈接

讀取多選項列表視圖(Read multiple choice ListView)

package com.MultiChoiceList;

import android.app.Activity;
import android.os.Bundle;
import android.util.SparseBooleanArray;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.TextView;

public class MultiChoiceList extends Activity {
 
 ListView list;
 TextView selection;
 
 String[] options = {"Option 1", "Option 2", "Option 3",
   "Option 4", "Option 5", "Option 6"};
 
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        list = (ListView)findViewById(R.id.list);
        selection = (TextView)findViewById(R.id.selection);
        
        ArrayAdapter<String> adapter
        = new ArrayAdapter<String>(this,
          android.R.layout.simple_list_item_multiple_choice,
          options);
        list.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
 
        list.setAdapter(adapter);
        
        list.setOnItemClickListener(new OnItemClickListener(){

   @Override
   public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
     long arg3) {
    // TODO Auto-generated method stub
    selection.setText(ReadSelection());
   }});
    }
    
    String ReadSelection(){
     
     String selected = "";
     int cntChoice = list.getCount();
     SparseBooleanArray sparseBooleanArray = list.getCheckedItemPositions();
     
     for(int i = 0; i < cntChoice; i++){
      if(sparseBooleanArray.get(i)) {
       selected += list.getItemAtPosition(i).toString() + "\n"; 
      }
        }
     
     return selected;
    }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="@string/hello"
    />
<TextView  
    android:id="@+id/selection"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    />
<ListView 
 android:id="@+id/list"
 android:layout_width="fill_parent"
 android:layout_height="wrap_content"/>
</LinearLayout>

2011年10月13日星期四

含多項選擇(multiple choice)的列表視圖(ListView)

通過 setChoiceMode(ListView.CHOICE_MODE_MULTIPLE) 以及 android.R.layout.simple_list_item_multiple_choice 佈局, 可以設定列表視圖(ListView)為多選項.

實例:

package com.MultiChoiceList;

import android.app.Activity;
import android.os.Bundle;
import android.widget.ArrayAdapter;
import android.widget.ListView;

public class MultiChoiceList extends Activity {
 
 ListView list;
 
 String[] options = {"Option 1", "Option 2", "Option 3",
   "Option 4", "Option 5", "Option 6"};
 
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        list = (ListView)findViewById(R.id.list);
        
        ArrayAdapter<String> adapter
        = new ArrayAdapter<String>(this,
          android.R.layout.simple_list_item_multiple_choice,
          options);
        list.setChoiceMode(ListView.CHOICE_MODE_MULTIPLE);
 
        list.setAdapter(adapter);
    }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="@string/hello"
    />
<ListView 
 android:id="@+id/list"
 android:layout_width="fill_parent"
 android:layout_height="wrap_content"/>
</LinearLayout>

2011年10月12日星期三

資本主義的危機 Crisis of Capitalism

2011年10月2日星期日

從 SD Card 中讀取圖像檔案

package com.AndroidLoadFromSD;

import java.io.File;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.os.Environment;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;

public class AndroidLoadFromSD extends Activity {
 
 ImageView Image;
 Button LoadButton;
 Bitmap bmImage;
 
  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.main);
      Image = (ImageView)findViewById(R.id.image);
      LoadButton = (Button)findViewById(R.id.load);
    
      LoadButton.setOnClickListener(new Button.OnClickListener(){

   @Override
   public void onClick(View v) {
    // TODO Auto-generated method stub
    
    String extStorage = Environment.getExternalStorageDirectory().toString();
       String file = new File(extStorage, "myFile.PNG").toString();
       Bitmap bm = BitmapFactory.decodeFile(file);
          Image.setImageBitmap(bm);
    
          Toast.makeText(AndroidLoadFromSD.this,
                  extStorage+"/myFile.PNG",
                  Toast.LENGTH_LONG).show();
        
   }});
  }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="vertical"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  >
<TextView
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:text="@string/hello"
  />
<Button
  android:id="@+id/load"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  android:text="Load Image (myFile.PNG)"
  />
<ImageView
  android:id="@+id/image"
  android:layout_width="fill_parent"
  android:layout_height="wrap_content"
  />
</LinearLayout>

相關文章:
- 儲存圖像到 SD Card 中

2011年10月1日星期六

儲存圖像到 SD Card 中

package com.AndroidSaveOnSD;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.os.Environment;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.Toast;

public class AndroidSaveOnSD extends Activity {
 
 ImageView Image;
 Button SaveButton;
 Bitmap bmImage;
 
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        Image = (ImageView)findViewById(R.id.image);
     SaveButton = (Button)findViewById(R.id.save);
     
     bmImage = BitmapFactory.decodeResource(getResources(), R.drawable.icon);
     Image.setImageBitmap(bmImage);
     
     SaveButton.setOnClickListener(new Button.OnClickListener(){

   @Override
   public void onClick(View v) {
    // TODO Auto-generated method stub
    
    String extStorage = Environment.getExternalStorageDirectory().toString();
    File file = new File(extStorage, "myFile.PNG");
    
    try {
     OutputStream outStream = new FileOutputStream(file);
     bmImage.compress(Bitmap.CompressFormat.PNG, 100, outStream);
     outStream.flush();
        outStream.close();
        Toast.makeText(AndroidSaveOnSD.this, 
          extStorage+"/myFile.PNG", 
          Toast.LENGTH_LONG).show();
    } catch (FileNotFoundException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();
     Toast.makeText(AndroidSaveOnSD.this, 
          e.toString(), 
          Toast.LENGTH_LONG).show();
    } catch (IOException e) {
     // TODO Auto-generated catch block
     e.printStackTrace();
     Toast.makeText(AndroidSaveOnSD.this, 
          e.toString(), 
          Toast.LENGTH_LONG).show();
    }
    
   }});
    }
}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
<TextView  
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="@string/hello"
    />
<ImageView
    android:id="@+id/image"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    />
<Button
    android:id="@+id/save"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content" 
    android:text="Save Image (myFile.PNG)"
    />
</LinearLayout>

注意須修改 AndroidManifest.xml 添加 "android.permission.WRITE_EXTERNAL_STORAGE" 權限.

相關文章:
- 從 SD Card 中讀取圖像檔案