Android expert on the path of Android custom properties Attr.xml, Typedarray use

Generally we are using android:xxx= "" ... The properties of such Android. But sometimes we need to use custom properties, especially when customizing the view.

The following steps are generally required:

1. define a attrs.xml file under the res/values file:

<?xml version= "1.0" encoding= "Utf-8"?><resources> <declare-styleable    name= "MyView" >           <attr name= "TextColor" format= "color"/> <attr name=           "textSize" format= "Dimension"/>      </ Declare-styleable>  </resources>

2. Rewrite Our custom view construction method. is to useR.styleable.myview Get our custom properties.

TypedArray usually last called . Recycle () method, in order to maintain consistency after using this attribute!

Package Com.example.viewdemo;import Android.annotation.suppresslint;import Android.content.context;import Android.content.res.typedarray;import Android.graphics.canvas;import Android.graphics.color;import Android.graphics.paint;import Android.graphics.paint.style;import Android.graphics.rect;import  Android.util.attributeset;import Android.view.view;public class MyView extends view{private Paint mpaint;   Private Context Mcontext;   private static final String mstring = "oh,god!";            Public MyView (Context context) {super (context);         } public MyView (Context Context,attributeset attrs) {super (context,attrs);         Mpaint = new Paint ();        TypedArray a = context.obtainstyledattributes (Attrs,r.styleable.myview); int textcolor = A.getcolor (R.styleable.myview_textcolor, 0XFFFFFF);//Note Add default value float textSize = a.getdimension (r.style Able.        Myview_textsize, 36);        Mpaint.settextsize (textSize);        Mpaint.setcolor (TextColor); A.recycLe ();        } @Override protected void OnDraw (canvas canvas) {super.ondraw (canvas);        Set the Fill Mpaint.setstyle (Style.fill);          Draw a rectangle, the first two are the coordinates of the upper left corner of the rectangle, the following two are the lower right corner coordinates canvas.drawrect (new Rect (Ten, Ten, Nine), mpaint);        Mpaint.setcolor (Color.Blue);    Draw Text Canvas.drawtext (mstring, ten, mpaint); }}

3. Use our custom attributes in the XML layout file. Note Prefix

<linearlayout xmlns:android= "http://schemas.android.com/apk/res/android"    xmlns:test= "http// Schemas.android.com/apk/res/com.example.viewdemo "      android:layout_width=" match_parent "    android:layout_ height= "Match_parent"    android:orientation= "vertical"    >    <com.example.viewdemo.myview         Android:layout_width= "Match_parent"        android:layout_height= "wrap_content"       test:textsize= "40px        " Test:textcolor= "#fff"          /></linearlayout>

Operating effect:

Android expert on the path of Android custom properties Attr.xml, Typedarray use