Question

我正在尝试在camera2 textureview上绘制一个矩形，当我运行代码时，我看到通常的移动方块的相机屏幕，当我点击（触摸）它时，应用程序崩溃，主题中出现错误。我也不确定我是否正确实现了自定义视图，以下是所有相关部分，希望得到一些帮助（我不确定我有一个好的布局xml，我在OnCrearte下添加了ViewGroup代码，不确定我甚至需要触摸xml ）

------- CameraActivity.java：

package com.example.android.camera2video;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.view.ViewGroup;

public class CameraActivity extends Activity {
    private  Context context;
    CustomView customview;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_camera);
        customview = new CustomView(this);
        final ViewGroup viewGroup = (ViewGroup) ((ViewGroup) this.findViewById(android.R.id.content)).getChildAt(0);
        viewGroup.addView(new CustomView(this));
        if (null == savedInstanceState) {
            getFragmentManager().beginTransaction()
                    .replace(R.id.container, Camera2VideoFragment.newInstance())
                    .commit();
        }
    }

}

------- CustomView.java

package com.example.android.camera2video;

import android.app.Activity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.PixelFormat;
import android.graphics.PorterDuff;
import android.os.Handler;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;




public class CustomView extends SurfaceView {

    private  Paint paint;
    private  SurfaceHolder mHolder;
    private  Context context;

    public CustomView(Context context) {
        super(context);
        mHolder = getHolder();
        mHolder.setFormat(PixelFormat.TRANSPARENT);
        this.context = context;
        paint = new Paint(Paint.ANTI_ALIAS_FLAG);
        paint.setColor(Color.WHITE);
        paint.setStyle(Paint.Style.STROKE);

    }
    public CustomView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public CustomView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        // real work here
    }

    private void doAdditionalConstructorWork() {

        // init variables etc.
    }
    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        if (event.getAction() == MotionEvent.ACTION_DOWN) {
            invalidate();
            if (mHolder.getSurface().isValid()) {
                final Canvas canvas = mHolder.lockCanvas();
                Log.d("touch", "touchRecieved by camera");
                System.err.println("EXIT 1");
                if (canvas != null) {
                    Log.d("touch", "touchRecieved CANVAS STILL Not Null");
                    canvas.drawColor(Color.TRANSPARENT, PorterDuff.Mode.CLEAR);
                    canvas.drawColor(Color.TRANSPARENT);
                    canvas.drawCircle(event.getX(), event.getY(), 100, paint);
                    mHolder.unlockCanvasAndPost(canvas);
                    new Handler().postDelayed(new Runnable() {
                        @Override
                        public void run() {
                            Canvas canvas1 = mHolder.lockCanvas();
                            if(canvas1 !=null){
                                canvas1.drawColor(0, PorterDuff.Mode.CLEAR);
                                mHolder.unlockCanvasAndPost(canvas1);
                            }

                        }
                    }, 1000);

                }
                mHolder.unlockCanvasAndPost(canvas);


            }
        }


        return false;
    }
}

----- fragment_camera2_video.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <com.example.android.camera2video.AutoFitTextureView
        android:id="@+id/texture"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentStart="true"
        android:layout_alignParentTop="true" />


    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:layout_alignParentStart="true"
        android:layout_below="@id/texture"
        android:background="#4285f4">

        <Button
            android:id="@+id/video"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:text="@string/record" />

        <ImageButton
            android:id="@+id/info"
            android:contentDescription="@string/description_info"
            style="@android:style/Widget.Material.Light.Button.Borderless"
            android:layout_width="4dp"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical|right"
            android:padding="20dp"
            android:src="@drawable/ic_action_info" />

    </FrameLayout>

</RelativeLayout>

Answer 1

一次只能绘制一个视图;一旦SurfaceView连接到相机，您就无法锁定它以便自己画画。

你的崩溃可能是因为你正在调用mHolder.unlockCanvasAndPost（canvas）;在空检查之外。

如果要绘制cameara预览，则需要在SurfaceView顶部放置第二个视图。

Android - CustomView - java.lang.IllegalStateException：Surface未锁定

1 个答案: