Android Master Advanced Tutorial (iii)----app for customizing view in Android.

Hello, everyone. Our tutorial today is to customize View Learning in the Android tutorial, for beginners, they are accustomed to the traditional Android page layout, the following code:

<?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"      >  <TextView        android:layout_width= " Fill_parent "       android:layout_height=" Wrap_content "       android:text=" @string/hello "      />  </LinearLayout>

Of course, the above layout can help us to complete the development of simple applications, but if you want to write a complex application, so it is a bit far-fetched, we do not believe that the source can be studied to see, master writing layout, such as the above layout master is usually written like this:

<?xml version= "1.0" encoding= "Utf-8"?>  <A>      <B></B>  </A>

Where a extends Linerlayout, B extends TextView.

To help make it easier for everyone to understand, I wrote a simple Demo with the following steps:

Start by creating a new Android project named Viewdemo .

Then customize a view class named MyView (extends View) . The code is as follows:

 PackageCom.android.tutor; ImportAndroid.content.Context; ImportAndroid.graphics.Canvas; ImportAndroid.graphics.Color; ImportAndroid.graphics.Paint; ImportAndroid.graphics.Rect; ImportAndroid.graphics.Paint.Style; ImportAndroid.util.AttributeSet; ImportAndroid.view.View;  Public classMyViewextendsView {PrivatePaint Mpaint; PrivateContext Mcontext; Private Static FinalString mstring = "Welcome to Mr Wei ' s Blog";  PublicMyView (Context context) {Super(context); }       PublicMyView (Context context,attributeset attr) {Super(CONTEXT,ATTR); } @Overrideprotected voidOnDraw (canvas canvas) {//TODO auto-generated Method Stub        Super. OnDraw (canvas); Mpaint=NewPaint (); //Set Brush ColorMpaint.setcolor (color.red); //Set the FillMpaint.setstyle (Style.fill); //draw a rectangle, the first two are the coordinates of the upper left corner of the rectangle, the next two are the lower right corner coordinatesCanvas.drawrect (NewRect (10, 10, 100, 100), mpaint);          Mpaint.setcolor (Color.Blue); //Draw TextCanvas.drawtext (mstring, 10, 110, Mpaint); }  }

Then add our custom View to the main.xml layout file with the following code:

<?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"      >  <TextView        android:layout_width= " Fill_parent "       android:layout_height=" Wrap_content "       android:text=" @string/hello "      />  <com.android.tutor.MyView      android:layout_width= "Fill_parent"        Android:layout_height= "fill_parent"   />  </LinearLayout>

Finally, the effect is as follows:

Android Master Advanced Tutorial (iii)----app for customizing view in Android.