package com.loaderman.customviewdemo;

import android.content.Context;

import android.graphics.Canvas;

import android.graphics.Color;

import android.graphics.Paint;

import android.util.AttributeSet;

import android.view.SurfaceHolder;

import android.view.SurfaceView;

public class DoubleBufferingTextView extends SurfaceView {

    private Paint mPaint;

    public DoubleBufferingTextView(Context context) {

        super(context);

        init();

    }

    public DoubleBufferingTextView(Context context, AttributeSet attrs) {

        super(context, attrs);

        init();

    }

    public DoubleBufferingTextView(Context context, AttributeSet attrs, int defStyle) {

        super(context, attrs, defStyle);

        init();

    }

    private void init() {

        mPaint = new Paint();

        mPaint.setColor(Color.RED);

        mPaint.setTextSize(30);

        getHolder().addCallback(new SurfaceHolder.Callback() {

            @Override

            public void surfaceCreated(SurfaceHolder holder) {

                drawText(holder);

            }

            @Override

            public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {

            }

            @Override

            public void surfaceDestroyed(SurfaceHolder holder) {

            }

        });

    }

    private void drawText(final SurfaceHolder holder) {

        new Thread(new Runnable() {

            @Override

            public void run() {

                for (int i = 0; i < 10; i++) {

                    Canvas canvas = holder.lockCanvas();

                    if (canvas != null) {

                        canvas.drawText(i + "", i * 30, 50, mPaint);

                    }

                    holder.unlockCanvasAndPost(canvas);

                    try {

                        Thread.sleep(800);

                    } catch (Exception e) {

                        e.printStackTrace();

                    }

                }

            }

        }).start();

    }

}