android shpe 三角形_自定义View实现三角形(正三角,倒三角)

最新推荐文章于 2024-08-18 03:39:11 发布

优达学城（Udacity）

最新推荐文章于 2024-08-18 03:39:11 发布

阅读量1.5k

点赞数

CC 4.0 BY-SA版权

文章标签： android shpe 三角形

本文链接：https://blog.youkuaiyun.com/weixin_29252859/article/details/112035209

该博客介绍了如何在Android中创建一个自定义View来绘制三角形，包括正三角形和倒三角形。通过TriangleView类，实现了颜色、形状模式（正三角或倒三角）的设置，并在onDraw()方法中利用Canvas和Path进行绘制。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

importandroid.content.Context;importandroid.content.res.TypedArray;importandroid.graphics.Canvas;importandroid.graphics.Color;importandroid.graphics.Paint;importandroid.graphics.Path;importandroid.support.annotation.IntDef;importandroid.support.annotation.Nullable;importandroid.util.AttributeSet;importandroid.view.View;importjava.lang.annotation.Retention;importjava.lang.annotation.RetentionPolicy;/*** 三角形*/

public class TriangleView extendsView{privatePaint paint;privatePath path;private intcolor;private intmode;private final int DEFAULT_WIDTH=48;private final int DEFAULT_HEIGHT=24;private int width = 0;private int height =0;/*** 倒三角*/

public static final int INVERTED = 0;/*** 正三角*/

public static final int REGULAR = 1;

@IntDef({INVERTED, REGULAR})

@Retention(RetentionPolicy.SOURCE)public @interfaceShapeMode {}publicTriangleView(Context context) {this(context,null);

}publicTriangleView(Context context, @Nullable AttributeSet attrs) {this(context,attrs,0);

}public TriangleView(Context context, @Nullable AttributeSet attrs, intdefStyleAttr) {super(context, attrs, defStyleAttr);

init(context,attrs);

}private voidinit(Context context,AttributeSet attrs){

TypedArray typedArray=context.obtainStyledAttributes(attrs, R.styleable.TriangleView);

color=typedArray.getColor(R.styleable.TriangleView_tlv_color, Color.BLACK);

mode=typedArray.getInt(R.styleable.TriangleView_tlv_mode, INVERTED);

typedArray.recycle();

paint= newPaint();

paint.setColor(color);

paint.setAntiAlias(true);

paint.setStyle(Paint.Style.FILL);

path= newPath();

}

@Overrideprotected void onMeasure(int widthMeasureSpec, intheightMeasureSpec) {super.onMeasure(widthMeasureSpec, heightMeasureSpec);

width=measureSize(widthMeasureSpec, DEFAULT_WIDTH);

height=measureSize(heightMeasureSpec, DEFAULT_HEIGHT);

setMeasuredDimension(width, height);

}private int measureSize(int measureSpec, intdefaultSize) {int newSize = 0;int mode =MeasureSpec.getMode(measureSpec);int size =MeasureSpec.getSize(measureSpec);switch(mode) {caseMeasureSpec.AT_MOST:

newSize=Math.min(size, defaultSize);break;caseMeasureSpec.EXACTLY:

newSize=size;break;caseMeasureSpec.UNSPECIFIED:

newSize=defaultSize;break;

}returnnewSize;

}public void setColor(intcolor){this.color=color;

paint.setColor(color);

invalidate();

}public void setMode(@ShapeMode intmode){this.mode=mode;

invalidate();

}

@Overrideprotected voidonDraw(Canvas canvas) {super.onDraw(canvas);

drawTriangle(canvas);

}private voiddrawTriangle(Canvas canvas) {if(mode==INVERTED) {

path.moveTo(0f, 0f);

path.lineTo(width, 0f);

path.lineTo(width/ 2.0f, height);

}else{

path.moveTo(width/2.0f,0f);

path.lineTo(0,height);

path.lineTo(width,height);

}

path.close();

canvas.drawPath(path, paint);

}