Android Series Lectures (2): Add Borders to the textview component

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Source code

AndroidProvided by the system itselfTextviewThe widget does not support borders, but you canTextviewTo add borders. We can use the following two methods:TextviewAdd a border for the widget.

1.Compile an inheritanceTextviewClass, andOndrawDraw borders in the event method.

2.Use9-patchFormat ImageTextviewTo set the border (this background image requires a border ).

InOndrawIt is very easy to draw borders in the event method.TextviewThe top, bottom, left, and right sides of the widget. TheCodeAs follows:

Package Net. blogjava. Mobile;

ImportAndroid. content. context;
ImportAndroid. Graphics. Canvas;
ImportAndroid. Graphics. paint;
ImportAndroid. util. attributeset;
ImportAndroid. widget. textview;

Public Class Bordertextview Extends Textview
{
@ Override
Protected Void Ondraw (canvas)
{
Super . Ondraw (canvas );
Paint paint = New Paint ();
// Set the border to black
Paint. setcolor (Android. Graphics. color. Black );
// Draw four sides of textview
Canvas. drawline ( 0 , 0 , This . Getwidth () - 1 , 0 , Paint );
Canvas. drawline ( 0 , 0 , 0 , This . Getheight () - 1 , Paint );
Canvas. drawline ( This . Getwidth () - 1 , 0 , This . Getwidth () - 1 , This . Getheight () - 1 , Paint );
Canvas. drawline ( 0 , This . Getheight () - 1 , This . Getwidth () - 1 , This . Getheight () - 1 , Paint );
}
Public Bordertextview (context, attributeset attrs)
{
Super (Context, attrs );
}
}

Note: If you want to textview transparent, that is, the textview the background color of the parent view is textview the background color of the component, 2 section 3 textview components that must be transparent with borders PNG image (except the border, the rest of the image is transparent ), then generate an image in 9-patch format.