Android学习（六） 文本框边框

BorderTextViews.java

package xiaosi.BorderTextView;
 
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.widget.TextView;
 
public class BorderTextViews extends TextView
{
    private Paint paint = null;
    private int color = Color.GRAY;
    public BorderTextViews(Context context, AttributeSet attrs)
    {
        super(context, attrs);
    }
    //设置边框颜色
    public void setPaintColor(int color){
        this.color = color;
    }
    @Override
    protected void onDraw(Canvas canvas)
    {
        super.onDraw(canvas);
        paint = new Paint();
        //给边框设置颜色
        paint.setColor(color);
        //上
        canvas.drawLine(0, 0, this.getWidth()-1, 0, paint);
        //左
        canvas.drawLine(0, 0, 0, this.getHeight()-1, paint);
        //下
        canvas.drawLine(0, this.getHeight()-1, this.getWidth()-1, this.getHeight()-1, paint);
        //右
        canvas.drawLine(this.getWidth()-1, 0, this.getWidth()-1, this.getHeight()-1, paint);
    }
}

Main_Activity.java

package xiaosi.BorderTextView;
 
import android.app.Activity;
import android.graphics.Color;
import android.os.Bundle;
 
public class BorderTextViewActivity extends Activity {
    /** Called when the activity is first created. */
    private BorderTextViews borderTextView = null;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        borderTextView = (BorderTextViews)findViewById(R.id.Border);
        borderTextView.setPaintColor(Color.GRAY);
    }
}

main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical"
    android:background="#CCFF66">
 
    <xiaosi.BorderTextView.BorderTextViews
        android:id="@+id/Border"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="#C71585"
        android:layout_marginTop="20dp"
        android:padding="10dp"
        android:layout_gravity="center"
        android:text="在画布上画边框" />
 
</LinearLayout>

预览效果：