安卓中描绘图形需要:
一,类:
1,画布Canvas;2,画笔Paint,3,用以展示的VIew子类
2,方法:
1,‘画’onDraw();2,将画布呈现setContentView();
package com.example.androidpractice;
import android.app.Activity;
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.os.Bundle;
import android.view.View;
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//展示画好的界面
setContentView(new MyView(this));
}
class MyView extends View{
//画笔
Paint paint;
public MyView(Context context){
super(context);
//设置画笔,当然也可以在onDraw()中设置
paint = new Paint();
paint.setColor(Color.BLACK);
}
//重写onDraw()方法
@Override
protected void onDraw(Canvas canvas) {
//画布来画
canvas.drawRect(100, 100, 300, 300, paint);
}
}
}