android自訂控制項(二) 入門,繼承View

轉載請註明地址:http://blog.csdn.net/ethan_xue/article/details/7313788

ps: 可根據apidemo裡LableView,list4,list6學習

文檔在dev guide/Framework Topics/User Interface/Building Custom Components

自訂控制項的步驟:

1 View的工作原理 
2 編寫View類 
3 為View類增加屬性 
4 繪製螢幕 
5 響應使用者訊息 
6 自訂回呼函數 

不多說,主要是Canvas, Paint, Path

public class CustomView1 extends View {private Paint mPaint;// private static final String mText = "drawText";private String mText = "drawText";public CustomView1(Context context, AttributeSet attrs) {super(context, attrs);}@Overrideprotected void onDraw(Canvas canvas) {super.onDraw(canvas);mPaint = new Paint();mPaint.setColor(Color.BLUE);// FILL填充, STROKE描邊,FILL_AND_STROKE填充和描邊mPaint.setStyle(Style.FILL);canvas.drawRect(new Rect(10, 10, 100, 100), mPaint);// 畫一個矩形mPaint.setColor(Color.GREEN);mPaint.setTextSize(35.0f);canvas.drawText(mText, 10, 60, mPaint);}}

布局

<?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"    ><ethan.customview1.CustomView1      android:layout_width="wrap_content"     android:layout_height="wrap_content"     /></LinearLayout>
注意,此時,在控制項下放一個textView的話,是顯示不出來的(TextView放在控制項上面可以顯示),以後再解決
 
http://download.csdn.net/detail/ethan_xue/4108820