android-Customizing View Creation Overview

1. Create a class that inherits view

1  Public classMyViewextendsview{2 3      PublicMyView (context context, AttributeSet Attrs) {//Constructors4         Super(context, attrs);5         //TODO auto-generated Constructor stub6     }7     8     protected voidOnDraw (canvas canvas)9     {Ten         Super. OnDraw (canvas);  OneCanvas.drawcolor (Color.Black);//draw a black background APaint paint=NewPaint ();//Create a brush - Paint.setcolor (color.red); -Canvas.drawrect (10,10,110,110, paint);//Draw a rectangle theCanvas.drawtext ("This is the string", "Ten,", "paint");//Write -RECTF rf1=NewRECTF (10,130,110,230);//Define a rectangle -Canvas.drawarc (Rf1, 0, 45,true, paint);//draw an arc, clockwise -Canvas.drawline (All-in-ten, Max, +, paint);//Draw Line +RECTF rf2=NewRECTF (150,130,250,230); -Canvas.drawoval (Rf2, paint);//Draw a circle +          A     } at  -}

The above is an example.

2. To invoke this myview, it needs to be called on Layout.xml, as

<Relativelayoutxmlns:android= "Http://schemas.android.com/apk/res/android"Xmlns:tools= "Http://schemas.android.com/tools"Android:layout_width= "Match_parent"Android:layout_height= "Match_parent"Android:paddingbottom= "@dimen/activity_vertical_margin"Android:paddingleft= "@dimen/activity_horizontal_margin"Android:paddingright= "@dimen/activity_horizontal_margin"Android:paddingtop= "@dimen/activity_vertical_margin"Tools:context=". Mainactivity " >    <TextViewAndroid:layout_width= "Wrap_content"Android:layout_height= "Wrap_content"Android:text= "@string/hello_world" />    <Com.example.myview.myviewAndroid:id= "@+id/myview"Android:layout_width= "Fill_parent"Android:layout_height= "Fill_parent"        /></Relativelayout>

Com.example.myview is the package that myview this class, and when XML is called, remember to add the package to the front.

This is another example of custom view

1  PackageCom.example.myview;2 3 ImportAndroid.content.Context;4 ImportAndroid.graphics.Bitmap;5 Importandroid.graphics.BitmapFactory;6 ImportAndroid.graphics.Canvas;7 ImportAndroid.graphics.Color;8 ImportAndroid.graphics.Paint;9 ImportAndroid.util.AttributeSet;Ten ImportAndroid.view.View; One  A  Public classMyview_pictureextendsview{ - Bitmap MB; - paint paint; the  -      PublicMyview_picture (Context context, AttributeSet attrs) { -         Super(context, attrs); -         //TODO auto-generated Constructor stub +          This. Initbitmap ();//Initialize picture -     } +      A      Public voidInitbitmap () at     { -Paint=NewPaint (); -mb=Bitmapfactory.decoderesource (Getresources (), r.drawable.indexgundom); -     } - @Override -     protected voidOnDraw (canvas canvas) in     { -         Super. OnDraw (canvas); toPaint.setantialias (true);//turn on anti-aliasing +Paint.setcolor (Color.White);//Set Brush Color -Paint.settextsize (15);//I guess the font size is set theCanvas.drawbitmap (MB, 10,10, paint);//Drawing *Canvas.drawtext ("Width of the Picture:" +mb.getwidth (), "A", ",");//Write $Canvas.drawtext ("Height of picture" +mb.getheight (), 150, 220, paint);Panax Notoginseng     } -      the  +}