个人android札记(三)

个人android笔记(三)
1、代码片段：获得最新通话记录的时长,格式为HH:mm:ss

public String getFormattedTime() {		long duration = 0;		Cursor cursor = getContentResolver().query(CallLog.Calls.CONTENT_URI,				new String[] { CallLog.Calls.DURATION }, null, null,				CallLog.Calls.DEFAULT_SORT_ORDER);		if (cursor != null) {			cursor.moveToPosition(0);//最新的一条			duration = cursor.getLong(0);		}		String pattern = "mm:ss";		if (duration > 3600) {			pattern = "HH:mm:ss";		}		SimpleDateFormat format = new SimpleDateFormat(pattern);		return format.format(new Date((long) duration * 1000));	}

2、颜色的使用。
在android是可以是使用Android.Graphics.Color类的Color.BLACK、Color.RED等来设置颜色的，但这样的做法，不符合MVC将模块与资源分开的思想，故强烈建议使用在res/values/color.xml中定义color变量

<resources>    <color name="my_red">#00ffff00</color></resources>

然后引用

int color = getResources().getColor(R.color.my_red);tv.setColor(color);

3、gallery简单应用：

private Gallery gallery;	private int[] myImage = {android.R.drawable.alert_dark_frame,							android.R.drawable.arrow_up_float,							android.R.drawable.btn_default_small,							android.R.drawable.checkbox_on_background};	@Override	protected void onCreate(Bundle savedInstanceState) {		// TODO Auto-generated method stub		super.onCreate(savedInstanceState);		setContentView(R.layout.ch3_15);		gallery = (Gallery)findViewById(R.id.ch3_15_gallery);		gallery.setAdapter(new ImageAdapter(this));			}		private class ImageAdapter extends BaseAdapter{		Context context;		public ImageAdapter(Context context){			this.context = context;		}		@Override		public int getCount() {			// TODO Auto-generated method stub			return myImage.length;		}		@Override		public Object getItem(int position) {			// TODO Auto-generated method stub			return position;		}		@Override		public long getItemId(int position) {			// TODO Auto-generated method stub			return position;		}		@Override		public View getView(int position, View convertView, ViewGroup parent) {			// TODO Auto-generated method stub			ImageView iv = new ImageView(this.context);			iv.setImageResource(myImage[position]);			iv.setScaleType(ImageView.ScaleType.FIT_XY);			iv.setLayoutParams(new Gallery.LayoutParams(120,120));			return iv;					}			}