我的安卓回顾之旅：安卓自定义view 的练习

回顾：安卓自定义view 的练习

学习安卓一年多了，最近重新做了一下自定义view的练习





直接贴代码：

首先是我们自定义的View类

[code]package example.jamase.drawbor;

import android.app.Notification;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.view.MotionEvent;
import android.view.View;

/**
 * Created by jamase on 2016/3/3.
 */
public class Drawview extends View {
    float prex;
    float prey;
    private Path path;
    public Paint paint = null;
    Bitmap cacheBitmap = null;
    Canvas cacheCanvas = null;
    public Drawview(Context context, int width, int hight) {
        super(context);
        cacheBitmap = Bitmap.createBitmap(width, hight, Bitmap.Config.ARGB_8888);
        cacheCanvas = new Canvas();
        paint = new Paint(Paint.DITHER_FLAG);
        path = new Path();
        paint.setColor(Color.RED);
        paint.setStyle(Paint.Style.STROKE);
        paint.setStrokeWidth(1);
        paint.setAntiAlias(true);
        paint.setDither(true);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        float x = event.getX();
        float y = event.getY();
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                path.moveTo(x, y);
                prex = x;
                prey = y;
                break;
            case MotionEvent.ACTION_MOVE:
                path.quadTo(prex, prey, x, y);
                prey = x;
                prey = y;
                break;
            case MotionEvent.ACTION_UP:
                cacheCanvas.drawPath(path, paint);
                path.reset();
                break;
        }
        invalidate();
        return true;

    }

    @Override
    protected void onDraw(Canvas canvas) {
        Paint bitPaint = new Paint();
        canvas.drawBitmap(cacheBitmap, 0, 0, bitPaint);
        canvas.drawPath(path, paint);
    }
}

然后是我们的MainActivity：

[code]package example.jamase.drawbor;

import android.app.Activity;
import android.graphics.BlurMaskFilter;
import android.graphics.Color;
import android.graphics.EmbossMaskFilter;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.DisplayMetrics;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.widget.LinearLayout;

public class MainActivity extends Activity {
    EmbossMaskFilter emboss;
    BlurMaskFilter blur;
    Drawview drawview;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        LinearLayout Line = new LinearLayout(this);
        DisplayMetrics displayMetrics = new DisplayMetrics();
        getWindowManager().getDefaultDisplay().getRealMetrics(displayMetrics);
        drawview = new Drawview(this, displayMetrics.widthPixels, displayMetrics.heightPixels);
        Line.addView(drawview);
        setContentView(Line);
        emboss = new EmbossMaskFilter(new float[]{1.5f, 1.5f, 1.5f}, 0.6f, 6, 4.2f);
        blur = new BlurMaskFilter(8, BlurMaskFilter.Blur.NORMAL);

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        MenuInflater inflater = new MenuInflater(this);
        inflater.inflate(R.menu.menu, menu);
        return super.onCreateOptionsMenu(menu);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case R.id.red:
                drawview.paint.setColor(Color.RED);
                item.setCheckable(true);
                break;
            case R.id.green:
                drawview.paint.setColor(Color.GREEN);
                item.setCheckable(true);
                break;
            case R.id.blue:
                drawview.paint.setColor(Color.BLUE);
                item.setCheckable(true);
                break;
            case R.id.width1:
                drawview.paint.setStrokeWidth(1);

                break;
            case R.id.width2:
                drawview.paint.setStrokeWidth(3);

                break;
            case R.id.width3:
                drawview.paint.setStrokeWidth(5);

                break;
            case R.id.blur:
                drawview.paint.setMaskFilter(blur);

                break;
            case R.id.emboss:
                drawview.paint.setMaskFilter(emboss);

                break;
        }
        return true;
    }
}

这个自定义画板目前只有有限的功能，有兴趣的朋友可以自己尝试为它增加一些功能。

对应资源下载：http://download.csdn.net/detail/u012608587/9458379

本文原创，转载请注明出处，谢谢！