textureview用法详解

If you want to display a live video stream or any content stream such as video or an OpenGL scene, you can use TextureView provided byAndroid in order to do that.

In order to use TextureView, all you need to do is get its SurfaceTexture.The SurfaceTexture can then be used to render content. In order to do this, you just need to do instantiate an object of this class and implement SurfaceTextureListener interface. Its syntax is given below：

private TextureView myTexture;public class MainActivity extends Activity implements SurfaceTextureListener{protected void onCreate(Bundle savedInstanceState) {   myTexture = new TextureView(this);   myTexture.setSurfaceTextureListener(this);   setContentView(myTexture);   }}

After that, what you need to do is to override its methods. The methods are listed as follows:

@Overridepublic void onSurfaceTextureAvailable(SurfaceTexture arg0, int arg1, int arg2) {}@Overridepublic boolean onSurfaceTextureDestroyed(SurfaceTexture arg0) {}@Overridepublic void onSurfaceTextureSizeChanged(SurfaceTexture arg0, int arg1,int arg2) {}@Overridepublic void onSurfaceTextureUpdated(SurfaceTexture arg0) {}

Any view that is displayed in the texture view can be rotated and its alpha property can be adjusted by using setAlpha and setRotation methods. Its syntax is given below:

myTexture.setAlpha(1.0f);myTexture.setRotation(90.0f);

Example

The below example demonstrates the use of TextureView class. It crates a basic application that allows you to view camera inside a texture view and change its angle , orientation e.t.c.

To experiment with this example , you need to run this on an actual device on which camera is present

package com.example.textureview;import java.io.IOException;import android.annotation.SuppressLint;import android.app.Activity;import android.graphics.SurfaceTexture;import android.hardware.Camera;import android.os.Bundle;import android.view.Gravity;import android.view.Menu;import android.view.TextureView;import android.view.TextureView.SurfaceTextureListener;import android.view.View;import android.widget.FrameLayout;public class MainActivity extends Activity implements SurfaceTextureListener {   private TextureView myTexture;   private Camera mCamera;   @SuppressLint("NewApi")   @Override   protected void onCreate(Bundle savedInstanceState) {      super.onCreate(savedInstanceState);      //setContentView(R.layout.activity_main);      myTexture = new TextureView(this);      myTexture.setSurfaceTextureListener(this);      setContentView(myTexture);   }   @Override   public boolean onCreateOptionsMenu(Menu menu) {      // Inflate the menu; this adds items to the action bar if it is present.      getMenuInflater().inflate(R.menu.main, menu);      return true;   }   @SuppressLint("NewApi")   @Override   public void onSurfaceTextureAvailable(SurfaceTexture arg0, int arg1,   int arg2) {      mCamera = Camera.open();     // Camera.Size previewSize = mCamera.getParameters().getPreviewSize();      //myTexture.setLayoutParams(new FrameLayout.LayoutParams(     // previewSize.width, previewSize.height, Gravity.CENTER));      try {

<span style="white-space:pre"></span>//设置mCamera的表面结构为surface         mCamera.setPreviewTexture(arg0);        } catch (IOException t) {        }      mCamera.startPreview();      myTexture.setAlpha(1.0f);      myTexture.setRotation(90.0f);   }   @Override   public boolean onSurfaceTextureDestroyed(SurfaceTexture arg0) {      mCamera.stopPreview();      mCamera.release();      return true;   }   @Override   public void onSurfaceTextureSizeChanged(SurfaceTexture arg0, int arg1,   int arg2) {   // TODO Auto-generated method stub   }   @Override   public void onSurfaceTextureUpdated(SurfaceTexture arg0) {   // TODO Auto-generated method stub   }}Here is the content of activity_main.xml<RelativeLayout xmlns: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" >   <TextureView      android:id="@+id/textureView1"      android:layout_width="wrap_content"      android:layout_height="wrap_content"      android:layout_alignParentTop="true"      android:layout_centerHorizontal="true" /></RelativeLayout>Here is the default content of AndroidManifest.xml<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"   package="com.example.textureview"   android:versionCode="1"   android:versionName="1.0" >   <uses-sdk      android:minSdkVersion="8"      android:targetSdkVersion="17" />   <uses-permission android:name="android.permission.CAMERA"/>   <application      android:allowBackup="true"      android:icon="@drawable/ic_launcher"      android:label="@string/app_name"      android:theme="@style/AppTheme" >      <activity          android:name="com.example.textureview.MainActivity"         android:label="@string/app_name" >         <intent-filter>            <action android:name="android.intent.action.MAIN" />            <category android:name="android.intent.category.LAUNCHER" />         </intent-filter>       </activity>   </application></manifest>

参考：http://www.tuicool.com/articles/eimY73