Compared with SurfaceView, TextureView does not create a separate Surface for drawing, which allows it to perform some transformation operations, set transparency, etc. just like the general View.

In addition, Textureview must be in a hardware accelerated window. The following example demonstrates how to create an opengl program through TextureView.

Based on the program of TextureView, we need to implement the interface of TextureView. Surface TextureListener. First, we give the code of Activity. In this class, we implement this interface:

package com.fyj.test;

import java.util.concurrent.atomic.AtomicBoolean;

import android.app.Activity;
import android.graphics.SurfaceTexture;
import android.os.Bundle;
import android.view.TextureView;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;

public class TextureviewtestActivity extends Activity implements TextureView.SurfaceTextureListener{

	private TextureView mTextureView;
	private Thread mProducerThread = null;
	private GLRendererImpl mRenderer;
	

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        requestWindowFeature(Window.FEATURE_NO_TITLE);
        getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,   
                WindowManager.LayoutParams.FLAG_FULLSCREEN);  
        mTextureView = new TextureView(this);
        mTextureView.setSurfaceTextureListener(this);
        mTextureView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_HIDE_NAVIGATION);//Hide virtual keys, navigator bar
        setContentView(mTextureView);
        
    	mRenderer = new GLRendererImpl(this);
    }


	@Override
	public void onSurfaceTextureAvailable(SurfaceTexture surface, int width,
			int height) {
		// TODO Auto-generated method stub
		mRenderer.setViewport(width, height);
		mProducerThread = new GLProducerThread(surface, mRenderer, new AtomicBoolean(true));
		mProducerThread.start();
	}

	@Override
	public boolean onSurfaceTextureDestroyed(SurfaceTexture surface) {
		// TODO Auto-generated method stub
		mProducerThread = null;
		return true;
	}


	@Override
	public void onSurfaceTextureSizeChanged(SurfaceTexture surface, int width,
			int height) {
		// TODO Auto-generated method stub
		mRenderer.resize(width, height);
		
	}


	@Override
	public void onSurfaceTextureUpdated(SurfaceTexture surface) {
		// TODO Auto-generated method stub
		
	}
}

Among them, in the method onSurface Texture Available, we open an OpenGL thread in which we perform some operations of OpenGL. The definition of the thread is as follows:

package com.fyj.test;

import java.util.concurrent.atomic.AtomicBoolean;

import javax.microedition.khronos.egl.EGL10;
import javax.microedition.khronos.egl.EGLConfig;
import javax.microedition.khronos.egl.EGLContext;
import javax.microedition.khronos.egl.EGLDisplay;
import javax.microedition.khronos.egl.EGLSurface;
import javax.microedition.khronos.opengles.GL;

import android.graphics.SurfaceTexture;
import android.opengl.GLUtils;

public class GLProducerThread extends Thread {

	private AtomicBoolean mShouldRender;
	private SurfaceTexture mSurfaceTexture;
	private GLRenderer mRenderer;
	
	private EGL10 mEgl;
	private EGLDisplay mEglDisplay = EGL10.EGL_NO_DISPLAY;
	private EGLContext mEglContext = EGL10.EGL_NO_CONTEXT;
	private EGLSurface mEglSurface = EGL10.EGL_NO_SURFACE;
	private GL mGL;
	
	
	private static final int EGL_CONTEXT_CLIENT_VERSION = 0x3098;
	private static final int EGL_OPENGL_ES2_BIT = 4;
	
	public interface GLRenderer {
		public void drawFrame();
	}
	
	public GLProducerThread(SurfaceTexture surfaceTexture, GLRenderer renderer, AtomicBoolean shouldRender) 
	{
		mSurfaceTexture = surfaceTexture;
		mRenderer = renderer;
		mShouldRender = shouldRender;
	}
	
	private void initGL()
	{
		mEgl = (EGL10)EGLContext.getEGL();
		
		mEglDisplay = mEgl.eglGetDisplay(EGL10.EGL_DEFAULT_DISPLAY);
		if (mEglDisplay == EGL10.EGL_NO_DISPLAY) {
			throw new RuntimeException("eglGetdisplay failed : " + 
																	GLUtils.getEGLErrorString(mEgl.eglGetError()));
		}
		
		int []version = new int[2];
		if (!mEgl.eglInitialize(mEglDisplay, version)) {
			throw new RuntimeException("eglInitialize failed : " + 
					GLUtils.getEGLErrorString(mEgl.eglGetError()));
		}
		
		int []configAttribs = {
				EGL10.EGL_BUFFER_SIZE, 32,
				EGL10.EGL_ALPHA_SIZE, 8,
				EGL10.EGL_BLUE_SIZE, 8,
				EGL10.EGL_GREEN_SIZE, 8,
				EGL10.EGL_RED_SIZE, 8,
				EGL10.EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
				EGL10.EGL_SURFACE_TYPE, EGL10.EGL_WINDOW_BIT,
				EGL10.EGL_NONE
		};
		
		int []numConfigs = new int[1];
		EGLConfig []configs = new EGLConfig[1]; 
		if (!mEgl.eglChooseConfig(mEglDisplay, configAttribs, configs, 1, numConfigs)) {
			throw new RuntimeException("eglChooseConfig failed : " + 
					GLUtils.getEGLErrorString(mEgl.eglGetError()));
		}
		
		int []contextAttribs = {
				EGL_CONTEXT_CLIENT_VERSION, 2,
				EGL10.EGL_NONE
		};
		mEglContext = mEgl.eglCreateContext(mEglDisplay, configs[0], EGL10.EGL_NO_CONTEXT, contextAttribs);
		mEglSurface = mEgl.eglCreateWindowSurface(mEglDisplay, configs[0], mSurfaceTexture, null);
		if (mEglSurface == EGL10.EGL_NO_SURFACE || mEglContext == EGL10.EGL_NO_CONTEXT) {
			int error = mEgl.eglGetError();
			if (error == EGL10.EGL_BAD_NATIVE_WINDOW) {
				throw new RuntimeException("eglCreateWindowSurface returned  EGL_BAD_NATIVE_WINDOW. " );
			}
			throw new RuntimeException("eglCreateWindowSurface failed : " + 
					GLUtils.getEGLErrorString(mEgl.eglGetError()));
		}
		
		if (!mEgl.eglMakeCurrent(mEglDisplay, mEglSurface, mEglSurface, mEglContext)) {
			throw new RuntimeException("eglMakeCurrent failed : " + 
					GLUtils.getEGLErrorString(mEgl.eglGetError()));
		}
		
		mGL = mEglContext.getGL();
	}
	
	private void destoryGL() 
	{
		mEgl.eglDestroyContext(mEglDisplay, mEglContext);
		mEgl.eglDestroySurface(mEglDisplay, mEglSurface);
		mEglContext = EGL10.EGL_NO_CONTEXT;
		mEglSurface = EGL10.EGL_NO_SURFACE;
	}
	
	public void run() 
	{
		initGL();
		
		if (mRenderer != null) {
			((GLRendererImpl)mRenderer).initGL();
		}
		
		while (mShouldRender != null && mShouldRender.get() != false) {
			if (mRenderer != null)
				mRenderer.drawFrame();
			mEgl.eglSwapBuffers(mEglDisplay, mEglSurface);
			
			try {
				sleep(5);
			} catch(InterruptedException e) {
				
			}
		}
		
		destoryGL();
	}
}

In this thread, we define the GLRenderer interface, the implementer of which is responsible for the specific OpenGL drawing code:

package com.fyj.test;

import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.FloatBuffer;
import java.nio.ShortBuffer;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.opengl.GLES20;
import android.opengl.GLUtils;
import android.util.Log;

import com.fyj.test.GLProducerThread.GLRenderer;

public class GLRendererImpl implements GLRenderer {
	
	private int mProgramObject;
	private int mWidth;
	private int mHeight;
	private FloatBuffer mVertices;
	private ShortBuffer mTexCoords;
	private Context mContext;
	private int mTexID;
	private static String TAG = "GLRendererImpl";

	private final float[] mVerticesData = { -0.5f, -0.5f, 0, 0.5f, -0.5f, 0, -0.5f, 0.5f, 0, 0.5f, 0.5f, 0 };
	private final short[] mTexCoordsData = {0, 1, 1, 1, 0, 0, 1, 0};

	public GLRendererImpl(Context ctx)
	{
		mVertices = ByteBuffer.allocateDirect(mVerticesData.length * 4)
				.order(ByteOrder.nativeOrder()).asFloatBuffer();
		mVertices.put(mVerticesData).position(0);
		
		mTexCoords = ByteBuffer.allocateDirect(mTexCoordsData.length * 2)
				.order(ByteOrder.nativeOrder()).asShortBuffer();
		mTexCoords.put(mTexCoordsData).position(0);
		
		mContext = ctx;
		
	}
	
	public void setViewport(int width, int height) 
	{
		mWidth = width;
		mHeight = height;
	}
	
	public void initGL()
	{
		comipleAndLinkProgram();
		
		loadTexture();
		
		GLES20.glClearColor(0,  0, 0, 0);
	}
	
	public void resize(int width, int height) 
	{
		mWidth = width;
		mHeight = height;
		
	}
	
	@Override
	public void drawFrame() {
		// TODO Auto-generated method stub
		GLES20.glViewport(0, 0, mWidth, mHeight);
		
		GLES20.glClear(GLES20.GL_COLOR_BUFFER_BIT);

		GLES20.glUseProgram(mProgramObject);
		
		GLES20.glVertexAttribPointer(0, 3, GLES20.GL_FLOAT, false, 0, mVertices);
		GLES20.glEnableVertexAttribArray(0);
		GLES20.glVertexAttribPointer(1, 2, GLES20.GL_SHORT, false, 0, mTexCoords);
		GLES20.glEnableVertexAttribArray(1);
		
		GLES20.glActiveTexture(GLES20.GL_TEXTURE0);
		GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, mTexID);
		int loc = GLES20.glGetUniformLocation(mProgramObject, "u_Texture");
		GLES20.glUniform1f(loc, 0);
		GLES20.glDrawArrays(GLES20.GL_TRIANGLE_STRIP, 0, 4);
	
		Log.i("GLRendererImpl", "drawing..." + mWidth);
	}

	
	private void loadTexture() {
		Bitmap b = BitmapFactory.decodeResource(mContext.getResources(), R.drawable.ic_launcher);
		if (b != null) {
			int []texID = new int[1];
			GLES20.glGenTextures(1, texID, 0);
			GLES20.glBindTexture(GLES20.GL_TEXTURE_2D, texID[0]);
			mTexID = texID[0];
			
			GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MAG_FILTER, 
					GLES20.GL_LINEAR);
			GLES20.glTexParameterf(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_MIN_FILTER, 
					GLES20.GL_LINEAR);
			
			GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_S,
					GLES20.GL_REPEAT);
			GLES20.glTexParameteri(GLES20.GL_TEXTURE_2D, GLES20.GL_TEXTURE_WRAP_T,
					GLES20.GL_REPEAT);
			
			GLUtils.texImage2D(GLES20.GL_TEXTURE_2D, 0, b, 0);
			b.recycle();
		}
	}
	
	private int loadShader(int shaderType, String shaderSource) {
		int shader;
		int[] compiled = new int[1];

		// Create the shader object
		shader = GLES20.glCreateShader(shaderType);

		if (shader == 0)
			return 0;

		// Load the shader source
		GLES20.glShaderSource(shader, shaderSource);

		// Compile the shader
		GLES20.glCompileShader(shader);

		// Check the compile status
		GLES20.glGetShaderiv(shader, GLES20.GL_COMPILE_STATUS, compiled, 0);

		if (compiled[0] == 0) {
			Log.e(TAG, GLES20.glGetShaderInfoLog(shader));
			GLES20.glDeleteShader(shader);
			return 0;
		}
		return shader;
	}
	
	private void comipleAndLinkProgram() {
		String vShaderStr = "attribute vec4 a_position;    \n"
				+"attribute vec2 a_texCoords; \n"
				+"varying vec2 v_texCoords; \n"
				+ "void main()                  \n"
				+ "{                            \n"
				+ "   gl_Position = a_position;  \n"
				+"    v_texCoords = a_texCoords; \n"
				+ "}                            \n";

		String fShaderStr = "precision mediump float;					  \n"
				+"uniform sampler2D u_Texture; \n"
				+"varying vec2 v_texCoords; \n"
				+ "void main()                                  \n"
				+ "{                                            \n"
				+ "  gl_FragColor = texture2D(u_Texture, v_texCoords) ;\n"
				+ "}                                            \n";

		int vertexShader;
		int fragmentShader;
		int programObject;
		int[] linked = new int[1];

		// Load the vertex/fragment shaders
		vertexShader = loadShader(GLES20.GL_VERTEX_SHADER, vShaderStr);
		fragmentShader = loadShader(GLES20.GL_FRAGMENT_SHADER, fShaderStr);

		// Create the program object
		programObject = GLES20.glCreateProgram();

		if (programObject == 0)
			return ;

		GLES20.glAttachShader(programObject, vertexShader);
		GLES20.glAttachShader(programObject, fragmentShader);

		// Bind vPosition to attribute 0
		GLES20.glBindAttribLocation(programObject, 0, "a_position");
		GLES20.glBindAttribLocation(programObject, 1, "a_texCoords");

		// Link the program
		GLES20.glLinkProgram(programObject);

		// Check the link status
		GLES20.glGetProgramiv(programObject, GLES20.GL_LINK_STATUS, linked, 0);

		if (linked[0] == 0) {
			Log.e(TAG, "Error linking program:");
			Log.e(TAG, GLES20.glGetProgramInfoLog(programObject));
			GLES20.glDeleteProgram(programObject);
			return  ;
		}

		mProgramObject = programObject;
	}
}

It should be noted that all EGL and GL-related operations must be placed in GLThread threads.