視頻直播開篇之camera+TextureSurface預覽

視頻直播開篇之camera+TextureSurface預覽

今天來說講使用camera接口和TextureSurface兩個來進行預覽

先看xml：

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".camera_texture_activity">
<TextureView
    android:id="@+id/preview_textureview"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />
</android.support.constraint.ConstraintLayout>

xml裏面就只有一個TextureView,這個就是用來預覽的控件。

再看代碼的實現：

package com.example.amei.cameraexample;

import android.graphics.SurfaceTexture;
import android.hardware.Camera;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.TextureView;

public class camera_texture_activity extends AppCompatActivity implements TextureView.SurfaceTextureListener {
    private static final String TAG = "cameraTexture";
    private TextureView mTextureView = null;
    private Camera mCamera = null;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_camera_texture_activity);
        mTextureView = findViewById(R.id.preview_textureview);


        mCamera = Camera.open(0);
        mTextureView.setSurfaceTextureListener(this);
    }

    @Override
    public void onSurfaceTextureAvailable(SurfaceTexture surfaceTexture, int i, int i1) {
        try{
            mCamera.setPreviewTexture(surfaceTexture);
            mCamera.startPreview();
        }catch (Exception e)
        {

        }


    }

    @Override
    public void onSurfaceTextureSizeChanged(SurfaceTexture surfaceTexture, int i, int i1) {

    }

    @Override
    public boolean onSurfaceTextureDestroyed(SurfaceTexture surfaceTexture) {
        mCamera.release();
        return false;
    }

    @Override
    public void onSurfaceTextureUpdated(SurfaceTexture surfaceTexture) {

    }
}

代碼裏面首先是實例化camera接口，而且打開camera.設置TextureView的監聽，這個監聽是爲了在合適的時間打開預覽以及釋放camera.從代碼中能夠看出在onSurfaceTextureAvailable裏面首先將surfaceture設置給camera,而後再預覽。這個和上一篇的suerface的顯示很像，在上一篇中是設置SurfaceHolder，最終的目的其實都是將顯示的數據畫在surface上面。